Compositions and methods for preventing infection

Abstract

Methods of treating preventing and / or substantially reducing a Pseudomonas aeruginosa (PA) infection and / or a Staphylococcus aureus (SA) infection by administration of a bivalent protein subunit-based vaccine are described. The vaccine can protect subjects with a prior history of exposure to SA from a new exposure to PA or SA, including methicillin resistant SA (MRSA), as well as being able to protecting with no prior exposure to a SA infection. Vaccine formulations are also described.

Description

Attorney Docket No.3289.0009WO COMPOSITIONS AND METHODS FOR PREVENTING INFECTION CROSS-REFERENCE TO RELATED APPLICATION This application claims the benefit of U.S. Provisional Patent Application Serial No. 63 / 694,983, filed September 16, 2024, the disclosure of which is incorporated herein by reference in its entirety. REFERENCE TO SEQUENCE LISTING SUBMITTED ELECTRONICALLY The content of the electronically submitted sequence listing in XML format (Name: 3289_0009_WO.xml; Size: 25,095 bytes; and Date of Creation: September 3, 2025) filed with the application is incorporated herein by reference in its entirety. GOVERNMENT SUPPORT This invention was made with government support under AI169781 awarded by the National Institutes of Health. The Government has certain rights in the invention. TECHNICAL FIELD The presently disclosed subject matter relates to methods of preventing and / or reducing infections, e.g., gram-negative bacterial infections, such as Pseudomonas aeruginosa (PA) infections and / or Staphylococcus aureus (SA) infections via administration of a multivalent protein subunit vaccine. The presently disclosed subject matter further relates to formulations of the vaccine. BACKGROUND Pseudomonas aeruginosa (PA) is an opportunistic gram-negative pathogen often associated with bloodstream infections, surgical site infections, ventilator associated pneumonia and hospital acquired urinary tract infections.1Among all gram-negative bacteria, PA were the third most frequent cause of bloodstream infections in USA representing 8.7% of the reported cases.2Recently, the increasing prevalence of multi-drug-resistant (MDR) PA presents a growing global threat, withAttorney Docket No.3289.0009WO significant implications for morbidity and mortality. The World Health Organization (WHO) has categorized MDR-PA strains as a top priority pathogen.3PA is also the predominant cause of lung infections in cystic fibrosis (CF) with >70% of patients being chronically infected with PA by their late teens.4Chronic lung infections in CF patients leads to a swift deterioration of pulmonary function, contributing to mortality in many CF patients.5Staphylococcus aureus (SA) is a gram-positive bacterial pathogen that causes skin and soft structure infection (SSSI), bacteremia, pneumonia, septic arthritis, and several toxin dependent diseases like toxic shock syndrome in humans.6SA is one of the most common causes of surgical wound infections.6Although SA is a common commensal bacterium to human skin and nares, but it is also the second most common bloodstream isolate in hospital settings.6The broad use of antibiotics in all settings has accelerated SA resistance toward clinically important antibiotics.7This trend has impacted treatment of invasive methicillin resistant SA (MRSA) infections resulting in elevated levels of mortality (15-40%) in cases of endocarditis or bacteremia.8Patients with SSSI due to initial MRSA infections often show recurrence of infections within 1 year of the initial infection, resulting in failure of surgical procedures and protracted antibiotic treatment.7Similarly, it has been reported that MRSA infections have increased ventilator-assisted pneumonia related morbidity and mortality rates significantly.7As with PA, 80% of CF patients have chronic MRSA infections by their late teens, also causing significant damage to their lungs.9Thus, there remains an ongoing need for effective vaccine formulations and methods for preventing and / or reducing PA and SA (e.g., MRSA) infections. SUMMARY This Summary lists several embodiments of the presently disclosed subject matter, and in many cases lists variations and permutations of these embodiments. This Summary is merely exemplary of the numerous and varied embodiments. Mention of one or more representative features of a given embodiment is likewise exemplary. Such an embodiment can typically exist with or without the feature(s) mentioned; likewise, those features can be applied to other embodiments of the presently disclosed subject matter, whether listed in this Summary or not. To avoidAttorney Docket No.3289.0009WO excessive repetition, this Summary does not list or suggest all possible combinations of such features. In some embodiments, the presently disclosed subject matter provides a method for preventing and / or substantially reducing a Pseudomonas aeruginosa (PA) infection and / or a Staphylococcus aureus (SA) infection in a subject in need thereof, wherein the method comprises administering to the subject a therapeutically effective amount of a composition comprising a vaccine comprising: (a) a fusion polypeptide wherein the fusion polypeptide comprises i) a fusion of a needle tip protein or an antigenic fragment thereof and / or a translocator protein or an antigenic fragment thereof from a Type III secretion system (T3SS) of PA and ii) an A1 subunit of the labile toxin (LTA1) from enterotoxigenic Escherichia coli; and (b) a polypeptide comprising the NEAr transporter 2 domain (NEAT2) of iron-regulated surface determinant protein B (IsdB), wherein the polypeptide comprising NEAT2 has an amino acid sequence of SEQ ID NO: 11, or a polypeptide having at least 90% homology to SEQ ID NO: 11. In some embodiments, the fusion of a needle tip protein or an antigenic fragment thereof and / or a translocator protein or the antigenic fragment thereof from the T3SS of PA is a polypeptide having an amino acid sequence of SEQ ID NO: 2 (PaF) or an amino acid sequence having at least 90% homology to the amino acid sequence of SEQ ID NO: 2. In some embodiments, the LTA1 is 5’ of the fusion of the needle tip protein or an antigenic fragment thereof and / or the translocator protein or an antigenic fragment thereof, optionally wherein the LTA1 has an amino acid sequence of SEQ ID NO: 6 or an amino acid sequence having at least 90% homology to the amino acid sequence of SEQ ID NO: 6. In some embodiments, the fusion polypeptide has an amino acid sequence of SEQ ID NO: 4 (L-PaF) or an amino acid sequence having at least 90% homology to SEQ ID NO: 4. In some embodiments, the composition further comprises a nanoemulsion or microemulsion, optionally wherein the microemulsion comprises squalene. In some embodiments, the composition further comprises a Toll-like receptor 4 (TLR4) agonist, optionally wherein the TLR4 agonist is a lipid A mimetic, further optionally wherein the TLR4 agonist is Bacterial Enzymatic Combinatorial Chemistry (BECC) candidate 438 (BECC438).Attorney Docket No.3289.0009WO In some embodiments, the SA infection comprises a methicillin-resistant SA (MRSA) infection. In some embodiments, the subject is a subject that was exposed to SA, optionally MRSA, prior to the administering to the subject a therapeutically effective amount of the composition. In some embodiments, the administering elicits opsonophagocytic killing (OPK) activity and / or elevated levels of secreted IL-17 from lung cells. In some embodiments, the administering produces a response to PA and / or SA that includes a cell-mediated response to eliminate SA and / or PA. In some embodiments, the subject has cystic fibrosis (CF). In some embodiments, the composition is administered to the subject via a route of administration selected from the group comprising intravenous, oral and inhalation. In some embodiments, the infection is substantially or entirely prevented in the subject. In some embodiments, the presently disclosed subject matter provides a vaccine formulation for preventing and / or reducing a Pseudomonas aeruginosa (PA) infection and / or a Staphylococcus aureus (SA) infection in a subject, the vaccine formulation comprising: (a) a fusion polypeptide wherein the fusion polypeptide comprises i) a fusion of a needle tip protein or an antigenic fragment thereof and / or a translocator protein or an antigenic fragment thereof from a Type III secretion system (T3SS) of PA and ii) an A1 subunit of the labile toxin (LTA1) from enterotoxigenic Escherichia coli; and (b) a polypeptide comprising the NEAr transporter 2 domain (NEAT2) of iron-regulated surface determinant protein B (IsdB), wherein the polypeptide comprising NEAT2 has an amino acid sequence of SEQ ID NO: 11, or a polypeptide having at least 90% homology to SEQ ID NO: 11. In some embodiments, the fusion polypeptide has an amino acid sequence of SEQ ID NO: 4 (L-PaF) or an amino acid having at least 90% homology to SEQ ID NO: 4. In some embodiments, the vaccine formulation further comprises a nanoemulsion or microemulsion, optionally wherein the microemulsion comprises squalene. In some embodiments, the vaccine formulation further comprises a Toll- like receptor 4 (TLR4) agonist, optionally wherein the TLR4 agonist is a lipid A mimetic, further optionally wherein the TLR4 agonist is Bacterial Enzymatic Combinatorial Chemistry (BECC) candidate 438 (BECC438).Attorney Docket No.3289.0009WO In some embodiments, the SA infection comprises a methicillin-resistant SA (MRSA) infection. In some embodiments, the vaccine formulation elicits protection against the PA and / or SA infection in a subject with a prior history of exposure to SA. In some embodiments, the vaccine formulation elicits opsonophagocytic killing (OPK) activity and / or elevated levels of secreted IL-17 in lung cells of the subject. In some embodiments, the vaccine formulation is effective in a subject that has cystic fibrosis (CF). In some embodiments, the vaccine formulation is formulated for administration to a subject via a route selected from the group comprising intravenous, oral and inhalation. In some embodiments, administration of the vaccine formulation to a subject substantially or entirely prevents a PA and / or SA infection in a subject. Accordingly, it is an object of the presently disclosed subject matter to provide a method of preventing and / or reducing a PA and / or SA infection using a bivalent protein subunit-based vaccine and to provide related vaccine formulations. This and other objects are achieved in whole or in part by the presently disclosed subject matter. Further, an object of the presently disclosed subject matter having been stated above, other objects and advantages of the presently disclosed subject matter will become apparent to those skilled in the art after a study of the following description, Figures, and Examples. BRIEF DESCRIPTIONS OF THE FIGURES The presently disclosed subject matter can be better understood by referring to the following figures. The drawings are not intended to limit the scope of this presently disclosed subject matter, which is set forth with particularity in the claims as appended or as subsequently amended, but merely to clarify and exemplify the presently disclosed subject matter. Figures 1A and 1B. PA and MRSA remain in the CF rat lung at least out to 14 days. Rats at 3 months of age were infected at day 0 with either a clinical mucoid PA strain PAM57-15 (Figure 1A) or a clinical S. aureus strain 0831 that is methicillin resistant (Figure 1B). CFUs collected from the lung homogenate at days 3-, 7-, 14-, (and 28-days for PA) following infection are readily cleared from the WT lung but persist in the CF lung to at least 14 days following infection. Figures 2A and 2B: L-PaF / ME / N2 immunization generates protection against clinically relevant MRSA strain SA0831 and PA strain mPA08-31.Attorney Docket No.3289.0009WO (Figure 2A) Mice were pre-exposed with MRSA before immunization with PBS, N2 or L-PaF / ME / N2 then challenged with MRSA strain SA0831 (n=10 per group, at least two separate experiments) and the survival of mice was monitored over a 14-day period. Statistical analysis was performed by log-rank (Mantel-Cox) test. p = 0.14 (PBS compared to N2 20 µg) p=0.02 (PBS compared to L-PaF / ME / N2 20 µg). (Figure 2B) Mice were pre-exposed with MRSA before immunization with N2 or L- PaF / ME / N2 then challenged with mucoid PA strain mPA08-31. Two days post infection mice were sacrificed, lungs were collected, homogenized, plated and CFU / lung was enumerated (n=5 / group). Result is mean and SD. Statistical analysis was performed by nonparametric test with Kruskal-Wallis test. *P < 0.05. Figures 3A-3F: Kinetics of serum antigen-specific IgG, IgG1 and IgA titers from naïve and MRSA pre-exposed mice. Naïve mice (n=10) were vaccinated three times biweekly (day 0, 14, 28) with the indicated formulation as indicated. Sera were collected from mice (day 0, 28, 42, 56) and titers measured for IgG, subtype IgG1 and IgA. For the MRSA pre-exposed group, mice (n=10) were exposed to MRSA and then vaccinated with the same schedule. Figures 3A-3C represent titers from naïve mice. Figures 3D-3F represent titers from MRSA pre-exposed mice. The individual titers are represented as Log10EU / ml. Each point represents the mean and error bars represent the SD of each group (n = 10 / group). (Figures 3A and 3D) Anti- PcrV serum IgG (top left panel), anti PopB serum IgG (top right panel) and anti-N2 serum IgG (bottom panel) titers were measured from L-PaF / ME / N2 formulations or PBS vaccinated groups. (Figures 3B and 3E) Anti-PcrV serum IgG1 (top left panel), anti PopB serum IgG1 (top right panel) and anti-N2 serum IgG1 (bottom panel) titers were measured from L-PaF / ME / N2 formulation or PBS vaccinated groups. (Figures 3C and 3F) Serum IgA titers against PcrV (top left panel), PopB (top right panel) and N2 (bottom panel) were measured from L-PaF / ME / N2 formulation or PBS vaccinated groups. Statistical analysis was performed by Mann-Whitney U test. Figures 4A-4D: Opsonophagocytosis killing of MRSA and PA in mouse sera elicited by L-PaF / ME / N2 formulations. Mouse sera from day 56 from groups described in Figures 3A-3F were heat inactivated and incubated MRSA or PA strains for 20 min. Mouse neutrophils and baby rabbit complement were added followed by a 1 h incubation. The mixture was plated on either MSA or PIA for CFU enumeration. Killing percentages were calculated as the difference between CFU before and afterAttorney Docket No.3289.0009WO the incubation. L-PaF / ME / N2 or PBS vaccinated sera from naïve mice mediated OPK of (Figure 4A) MRSA and (Figure 4B) PA. L-PaF / ME / N2 or PBS vaccinated sera from MRSA pre-exposed mice mediated OPK of (Figure 4C) MRSA and (Figure 4D) PA. Statistical analysis was performed by nonparametric test with Kruskal-Wallis test. Error bar represents SD and each experiment was at least performed twice with quadruple technical repeats. *P < 0.05; **P < 0.01. Figures 5A and 5B: Frequency of IL-17 and IFN-γ secreting cells following antigen-specific stimulation. Lung single cell suspensions were used to assess antigen-specific IL-17 and IFN-γ secreting cells using ELISpot analysis. Cells from each immunized group were incubated with 5 µg / ml either PcrV or PopB or N2 and incubated for 24 h at 37 °C. IL-17 and IFN-γ secreting cells are presented here as spot-forming cells (SFC) / 106cells. (Figure 5A) Level of IL-17 and IFN-γ secreting lung cells from naïve mice. (Figure 5B) Level of IL-17 and IFN-γ secreting lung cells from MRSA pre-exposed mice. All the data are plotted as means ± SD for individual mice in each group. Statistical analysis was performed by nonparametric test with Kruskal-Wallis test. *P < 0.05; **P < 0.01; ***P < 0.001. Figures 6A-6D: Lung cells from L-PaF / ME / N2 vaccinated mice secrete pro-inflammatory cytokines when stimulated with PcrV, PopB, and N2. Single- cell suspensions of lung cells were stimulated with 10 μg / ml of (Figures 6A and 6C) PcrV, PopB, or (Figure 6B and 6D) N2 at 37 °C for 48 h. (Figures 6A and 6B) IL- 17A, IL-2, and IL-22 secretion from samples taken from naïve mice. (Figures 6C and 6D) IL-17A, IL-2, and IL-22 secretion from samples taken from MRSA pre-exposed mice. Cytokine levels were measured using MesoScale Discovery (MSD) analysis according to the manufacturer’s guidelines and are reported as pg / ml per 106cells. Data are presented as mean ± SD (n = 5) for each group. Statistical analysis was conducted using the Kruskal-Wallis nonparametric test. *P < 0.05; **P < 0.01. Figures 7A-7D: N2 dose escalation study with L-PaF / ME generates protection against MRSA SA0831 or PA mPA08-31 strains in the mouse lung infection model. Mice were vaccinated with PBS, L-PaF / ME / N21 µg, L-PaF / ME / N2 10 µg or L-PaF / ME / N220 µg formulations. (Figure 7A) Mice were challenged with MRSA strain SA0831 (n=10 per group, at least two separate experiments). Statistical analysis was performed by log-rank (Mantel-Cox) test. p = 0.0003 (PBS compared to L-PaF / ME / N2 1 µg or L-PaF / ME / N2 10 µg) p = 0.0018 (PBS compared to L-Attorney Docket No.3289.0009WO PaF / ME / N220 µg). (Figure 7B) Mice were vaccinated with L-PaF / ME / N21 µg, L- PaF / ME / N210 µg or L-PaF / ME / N220 µg formulation then challenged with mucoid PA strain mPA08-31. Two days post-infection, mice were sacrificed, lungs were homogenized, plated, and CFU was enumerated. Result is mean and SD and n=5 per group. Statistical analysis was performed by nonparametric test with Kruskal-Wallis test. L-PaF / ME / N2 vaccination protect pre-MRSA exposed mice against MRSA SA0831 or PA mPA08-31 strains in the mouse lung infection model. Mice were pre- exposed with MRSA three times with two weeks interval IN, vaccinated with L- PaF / ME / N21 µg, L-PaF / ME / N210 µg, L-PaF / ME / N220 µg formulations, or PBS. (Figure 7C) Mice were challenged with MRSA strain SA0831 (n=10 per group, at least two separate experiments). Statistical analysis was performed by log-rank (Mantel-Cox) test. p = 0.001 (PBS compared to L-PaF / ME / N21 µg or L-PaF / ME / N2 10 µg) p = 0.019 (PBS compared to L-PaF / ME / N220 µg) (Figure 7D) Mice were pre-exposed with MRSA three times with two weeks interval via IN, then vaccinated with L-PaF / ME / N21 µg, L-PaF / ME / N210 µg, L-PaF / ME / N220 µg formulations, or PBS then challenged with mucoid PA strain mPA08-31. Two days post infection mice were sacrificed, lungs were homogenized, plated, and CFU was enumerated. Result is mean and SD and n=5 per group. Statistical analysis was performed by nonparametric test with Kruskal-Wallis test. *P < 0.05. Figures 8A-8G: L-PaF / ME / N2 vaccination induces serum IgG titers and protect naïve rabbits against clinically relevant MRSA and PA strains in the lethal pneumonia models. All the rabbits were vaccinated with L-PaF / ME / N2 formulations or PBS via IN route three times. Serum was collected and IgG titers determined. The individual titers are represented as Log10EU / ml. Each point represents the mean and error bars represent the SD of each group (n = 4 / group). (Figure 8A) Anti-PcrV serum IgG (upper left panel), anti PopB serum IgG (upper right panel) and anti-N2 serum IgG (bottom panel) titers were measured from L- PaF / ME / N2 formulation or PBS vaccinated groups. Statistical analysis was performed by Mann-Whitney U test. In the pneumonia models, all the vaccinated rabbits were challenged with lethal doses of MRSA or PA. (Figure 8B) Rabbits (n = 4) were challenged with a lethal dose of MRSA strain SA0831 via 1.5 mL PBS containing 1 × 10⁹ CFU / mL. PBS immunized rabbits were sacrificed between 19-30 hours post challenge (one at 19 hours, one at 29 hours, and two at 30 hours post challenge).Attorney Docket No.3289.0009WO (Figure 8C) Rabbits (n = 4) were challenged with a lethal dose of PA strain mPA08- 31 via 1.5 mL PBS containing 9 × 10⁷ CFU / mL. PBS immunized rabbits were sacrificed between 25-29 hours post challenge (one at 25 hours and three at 29 hours post challenge). Immunization of rabbits with L-PaF / ME / N2 formulations reduces bacterial lung burden associated with (Figure 8D) MRSA challenge and (Figure 8E) PA challenge. Results are mean and SD and n=4 per group. Statistical analysis was performed by nonparametric test with Kruskal-Wallis test. *P < 0.05. Pathological changes in the lungs of rabbits challenged with MRSA and PA. Histological alterations observed in representative lung samples collected at the time of euthanasia. (Figure 8F) MRSA challenged rabbit lungs immunized with (left panel) PBS, (center panel) L-PaF / ME / N250 µg and (right panel) L-PaF / ME / N2100 µg. (Figure 8G) PA challenged rabbit lungs immunized with (left panel) PBS, (center panel) L- PaF / ME / N250 µg and (right panel) L-PaF / ME / N2100 µg. Figures 9A-9G: L-PaF / ME / N2 vaccination induces serum IgG titers and protect MRSA pre-exposed rabbits against clinically relevant MRSA and PA strains in the lethal pneumonia models. All the rabbits were pre-exposed with MRSA two times with four weeks interval via IN, then vaccinated with L-PaF / ME / N2 formulations or PBS via IN route three times. Serum was collected and IgG titers determined. The individual titers are represented as Log10EU / ml. Each point represents the mean and error bars represent the SD of each group (n = 4 / group). (Figure 9A) Anti-PcrV serum IgG (left panel), anti PopB serum IgG (center panel) and anti-N2 serum IgG (right panel) titers were measured from L-PaF / ME / N2 formulation or PBS vaccinated groups. In the pneumonia models, all pre-exposed, vaccinated rabbits were challenged with lethal doses of MRSA or PA. (Figure 9B) Rabbits (n = 4) were challenged with a lethal dose of MRSA strain SA0831 via 1.5 mL PBS containing 1 × 10⁹ CFU / mL. PBS immunized rabbits were sacrificed between 19-30 hours post challenge (three at 19 hours and one at 30 hours post challenge) (Figure 9C) Rabbits (n = 3 / 4) were challenged with a lethal dose of PA strain mPA08-31 via 1.5 mL PBS containing 9 × 10⁷ CFU / mL. PBS immunized rabbits were sacrificed between 19-29 hours post challenge (one at 19 hours and two at 29 hours post challenge). Immunization of rabbits with L-PaF / ME / N2 formulation reduces bacterial lung burden associated with (Figure 9D) MRSA challenge and (Figure 9E) PA challenge. Results are mean and SD and n=4 per group. StatisticalAttorney Docket No.3289.0009WO analysis was performed by nonparametric test with Kruskal-Wallis test. *P < 0.05. Pathological changes in the lungs of rabbits pre-exposed with MRSA for two times followed by vaccination then challenged with MRSA and PA. Histological alterations observed in representative lung samples collected at the time of euthanasia. (Figure 9F) MRSA challenged rabbit lungs pre-exposed with MRSA then immunized with (left panel) PBS, (middle panel) L-PaF / ME / N250 µg and (right panel) L-PaF / ME / N2 100 µg. (Figure 9G) PA challenged rabbit lungs pre-exposed with MRSA then immunized with (left panel) PBS, (middle panel) L-PaF / ME / N2 50 µg and (right panel) L-PaF / ME / N2100 µg. Figures 10A-10D: L-PaF / ME / N2 / BECC protects against clinically relevant MRSA and PA strains in lethal wound infection models. MRSA-pre- exposed Sprague-Dawley rats (n=6 / group) were vaccinated subcutaneously with L- PaF / ME / N2 (5 μg or 10 μg) and BECC (0.5 μg or 1.0 μg) on days 0, 14, and 28. Control groups were vaccinated with PBS. On day 56, rats were subjected to 12 mm bilateral wound introduction (biopsy punch, ~ 1 mm deep) and infected with (Figures 10A and 10C) a lethal dose of MRSA strain SA0831 (1 × 107CFU) or (Figures 10B and 10D) a lethal dose of PA strain mPA08-31 (1 × 10⁷ CFU). Wound size (Figures 10A and 10B) and rat weight (Figures 10C and 10D) were monitored daily. Figure 11: Structure of Bacterial Enzymatic Combinatorial Chemistry compound 438 (BECC438). DETAILED DESCRIPTION The present disclosure relates, in some aspects, to a vaccine and the use thereof to prevent and / or reduce a Pseudomonas aeruginosa (PA) infection in a patient, including in a cystic fibrosis (CF) patient. The vaccine can also be used to prevent and / or reduce a Staphylococcus aureus (SA) infection in a patient (e.g., in a CF patient), particularly a methicillin-resistant S. aureus (MRSA) infection. Such methods and compositions for the prevention and / or reduction of PA, SA, and / or MRSA infections as disclosed herein can prevent or ameliorate severe lung dysfunction in CF patients as well as other patients with pulmonary maladies. The methods can also prevent and / or reduce SA and / or PA infections in patients with a prior history of exposure to SA (e.g., MSRA). In some aspects, the methods and compositions can prevent and / or reduce SA and / or PA infections in wounds.Attorney Docket No.3289.0009WO More particularly, disclosed herein is a bivalent subunit vaccine that comprises subunits of two different pathogens, i.e., PA and SA. In some aspects, the vaccine is based on a vaccine platform formulated to expedite immune clearance of PA from the lung, thereby offering vulnerable patients protection from infection by this ubiquitous opportunistic pathogen. The highly conserved surface localized proteins of the type III secretion system apparatus (T3SA) have been targeted. For example, in some embodiments, the T3SA protein targets are PcrV and PopB, the outer most proteins of the T3SA. These proteins are important for virulence. PcrV and PopB (or antigenic fragments thereof) can be fused to produce a fusion referred to as “PaF” (or “Pa fusion”). PaF can then be genetically fused to the LTA1 subunit of double-mutant labile toxin (dmLT) from enterotoxigenic E. coli to give “L-PaF”. The LTA1 subunit can elicit a strong IL-17 response that, at least in some aspects, appears to be important for protection against pathogens at mucosal sites. According to the presently disclosed subject matter, the SA iron-regulated surface determinant protein IsdB or at least the portion thereof referred to as the NEAr transporter 2 domain (NEAT2 or N2) or an antigenic fragment of NEAT2 is added to the L-PaF formulation. A vaccine comprising recombinant IsdB was previously studied in a phase III clinical trial. However, while highly immunogenic, the recombinant IsdB vaccine failed in provide protection in humans in this trial and this correlated with a lack of IL-17 production. Without being bound by any particular theory or mechanism of action, the present disclosure is premised at least in part on the discovery that, adding IsdB, or at least the portion of IsdB referred to as NEAT2, to the L-PaF vaccine formulation can elicit a more robust vaccine that targets two pathogens, PA and SA and provides a cell-mediated response. Thus, disclosed herein is a bivalent “L-PaF / N2” vaccine. As described further hereinbelow in the Examples, results of studies with the L-PaF / N2 vaccine demonstrate that L-PaF / IsdB protects against PA and MRSA in multiple animal models (mice, rabbits, and rats). In addition, the humoral response via antibody titers and opsonophagocytic activity was evaluated, as well as the cell-mediated response via IL-17 secretion levels. The presently disclosed subject matter now will be described more fully hereinafter, in which some, but not all embodiments of the presently disclosed subject matter are described. Indeed, the presently disclosed subject matter can be embodiedAttorney Docket No.3289.0009WO in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Throughout this application, various publications are referenced. The disclosures of these publications in their entireties are hereby incorporated by reference into this application in order to more fully describe the state of the art to which this pertains. The references disclosed are also individually and specifically incorporated by reference herein for the material contained in them that is discussed in the sentence in which the reference is relied upon. I. Definitions The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the presently disclosed subject matter. While the following terms are believed to be well understood by one of ordinary skill in the art, the following definitions are set forth to facilitate explanation of the presently disclosed subject matter. All technical and scientific terms used herein, unless otherwise defined below, are intended to have the same meaning as commonly understood by one of ordinary skill in the art. References to techniques employed herein are intended to refer to the techniques as commonly understood in the art, including variations on those techniques or substitutions of equivalent techniques that would be apparent to one of skill in the art. While the following terms are believed to be well understood by one of ordinary skill in the art, the following definitions are set forth to facilitate explanation of the presently disclosed subject matter. In describing the presently disclosed subject matter, it will be understood that a number of techniques and steps are disclosed. Each of these has individual benefit and each can also be used in conjunction with one or more, or in some cases all, of the other disclosed techniques. Accordingly, for the sake of clarity, this description will refrain from repeating every possible combination of the individual steps in an unnecessary fashion. Nevertheless, the specification and claims should be read with the understanding that such combinations are entirely within the scope of the invention and the claims.Attorney Docket No.3289.0009WO Following long-standing patent law convention, the terms “a”, “an”, and “the” refer to “one or more” when used in this application, including the claims. Thus, for example, reference to "an antibiotic" includes a plurality of such antibiotics, and so forth. Unless otherwise indicated, all numbers expressing quantities of ingredients, reaction conditions, and so forth used in the specification and claims are to be understood as being modified in all instances by the term “about”. Accordingly, unless indicated to the contrary, the numerical parameters set forth in this specification and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by the presently disclosed subject matter. As used herein, the term “about,” when referring to a value or to an amount of a composition, dose, homology or sequence identity (e.g., when comparing two or more nucleotide or amino acid sequences), mass, weight, temperature, time, volume, concentration, percentage, etc., is meant to encompass variations of in some embodiments ±20%, in some embodiments ±10%, in some embodiments ±5%, in some embodiments ±1%, in some embodiments ±0.5%, and in some embodiments ±0.1% from the specified amount, as such variations are appropriate to perform the disclosed methods or employ the disclosed compositions. The term “comprising”, which is synonymous with “including” “containing” or “characterized by” is inclusive or open-ended and does not exclude additional, unrecited elements or method steps. “Comprising” is a term of art used in claim language which means that the named elements are essential, but other elements can be added and still form a construct within the scope of the claim. As used herein, the phrase “consisting of” excludes any element, step, or ingredient not specified in the claim. When the phrase “consists of” appears in a clause of the body of a claim, rather than immediately following the preamble, it limits only the element set forth in that clause; other elements are not excluded from the claim as a whole. As used herein, the phrase “consisting essentially of” limits the scope of a claim to the specified materials or steps, plus those that do not materially affect the basic and novel characteristic(s) of the claimed subject matter.Attorney Docket No.3289.0009WO With respect to the terms “comprising”, “consisting of”, and “consisting essentially of”, where one of these three terms is used herein, the presently disclosed and claimed subject matter can include the use of either of the other two terms. As used herein, the term “and / or” when used in the context of a listing of entities, refers to the entities being present singly or in combination. Thus, for example, the phrase “A, B, C, and / or D” includes A, B, C, and D individually, but also includes any and all combinations and subcombinations of A, B, C, and D. An "increase" can refer to any change that results in a greater amount of a symptom, disease, composition, condition or activity. An increase can be any individual, median, or average increase in a condition, symptom, activity, composition in a statistically significant amount. Thus, the increase can be a 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or 100% increase so long as the increase is statistically significant. As used herein, a "decrease" can refer to any change that results in a smaller amount of a symptom, disease, composition, condition, or activity. A substance is also understood to decrease the genetic output of a gene when the genetic output of the gene product with the substance is less relative to the output of the gene product without the substance. Also, for example, a decrease can be a change in the symptoms of a disorder such that the symptoms are less than previously observed. A decrease can be any individual, median, or average decrease in a condition, symptom, activity, composition in a statistically significant amount. Thus, the decrease can be a 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or 100% decrease so long as the decrease is statistically significant. As used herein, "inhibit," "inhibiting," and "inhibition" mean to decrease an activity, response, condition, disease, or other biological parameter. This can include but is not limited to the complete ablation of the activity, response, condition, or disease. This can also include, for example, a 10% reduction in the activity, response, condition, or disease as compared to the native or control level. Thus, the reduction can be a 10, 20, 30, 40, 50, 60, 70, 80, 90, 100%, or any amount of reduction in between as compared to native or control levels. By “reduce” or other forms of the word, such as “reducing” or “reduction,” in the context of a bacterial infection is meant lowering the number of bacteria or the number of viable bacteria (i.e., colony forming units (CFUs) of a bacteria). It can alsoAttorney Docket No.3289.0009WO refer to lowering a level of a biological marker of the infection (e.g., lowering white blood cell count in a subject with the infection, etc.). It is understood that this is typically in relation to some standard or expected value, in other words it is relative (e.g., to the number or level prior to treatment), but that it is not always necessary for the standard or relative value to be referred to. By “prevent” or other forms of the word, such as “preventing” or “prevention,” is meant to stop a particular event or characteristic, to stabilize or delay the development or progression of a particular event or characteristic, or to minimize the chances that a particular event or characteristic will occur. Prevent does not require comparison to a control as it is typically more absolute than, for example, reduce. As used herein, something could be reduced but not prevented, but something that is reduced could also be prevented. Likewise, something could be prevented but not reduced, but something that is prevented could also be reduced. It is understood that where reduce or prevent are used, unless specifically indicated otherwise, the use of the other word is also expressly disclosed. As used herein, the term “subject” refers to any individual who is the target of administration or treatment. The subject can be a vertebrate, for example, a mammal. In one aspect, the subject can be human, non-human primate, bovine, equine, porcine, canine, or feline. The subject can also be a guinea pig, rat, hamster, rabbit, mouse, or mole. Thus, the subject can be a human or veterinary patient. The term “patient” refers to a subject under the treatment of a clinician, e.g., physician. The term “therapeutically effective” refers to the amount of the composition used is of sufficient quantity to ameliorate one or more causes or symptoms of a disease or disorder. Such amelioration only requires a reduction or alteration, not necessarily elimination. The term “treatment” refers to the medical management of a patient with the intent to cure, ameliorate, stabilize, or prevent a disease, pathological condition, or disorder. This term includes active treatment, that is, treatment directed specifically toward the improvement of a disease, pathological condition, or disorder, and also includes causal treatment, that is, treatment directed toward removal of the cause of the associated disease, pathological condition, or disorder. In addition, this term includes palliative treatment, that is, treatment designed for the relief of symptoms rather than the curing of the disease, pathological condition, or disorder; preventativeAttorney Docket No.3289.0009WO treatment, that is, treatment directed to minimizing or partially or completely inhibiting the development of the associated disease, pathological condition, or disorder; and supportive treatment, that is, treatment employed to supplement another specific therapy directed toward the improvement of the associated disease, pathological condition, or disorder. “Effective amount” of an agent refers to a sufficient amount of an agent to provide a desired effect. The amount of agent that is “effective” will vary from subject to subject, depending on many factors such as the age and general condition of the subject, the particular agent or agents, and the like. Thus, it is not always possible to specify a quantified “effective amount.” However, an appropriate “effective amount” in any subject case can be determined by one of ordinary skill in the art using routine experimentation. Also, as used herein, and unless specifically stated otherwise, an “effective amount” of an agent can also refer to an amount covering both therapeutically effective amounts and prophylactically effective amounts. An “effective amount” of an agent necessary to achieve a therapeutic effect can vary according to factors such as the age, sex, and weight of the subject. Dosage regimens can be adjusted to provide the optimum therapeutic response. For example, several divided doses can be administered daily, or the dose can be proportionally reduced as indicated by the exigencies of the therapeutic situation. A "pharmaceutically acceptable" component can refer to a component that is not biologically or otherwise undesirable, i.e., the component can be incorporated into a pharmaceutical formulation provided by the disclosure and administered to a subject as described herein without causing significant undesirable biological effects or interacting in a deleterious manner with any of the other components of the formulation in which it is contained. When used in reference to administration to a human, the term generally implies the component has met the required standards of toxicological and manufacturing testing or that it is included on the Inactive Ingredient Guide prepared by the U.S. Food and Drug Administration. As used herein, "pharmaceutically acceptable carrier" (sometimes referred to as a “carrier”) means a carrier or excipient that is useful in preparing a pharmaceutical or therapeutic composition that is generally safe and non-toxic and includes a carrier that is acceptable for veterinary and / or human pharmaceutical or therapeutic use. The terms "carrier" or "pharmaceutically acceptable carrier" can include, but are notAttorney Docket No.3289.0009WO limited to, phosphate buffered saline solution, water, emulsions (such as an oil / water or water / oil emulsion) and / or various types of wetting agents. As used herein, the term "carrier" encompasses, but is not limited to, any excipient, diluent, filler, salt, buffer, stabilizer, solubilizer, lipid, stabilizer, or other material well known in the art for use in pharmaceutical formulations and as described further herein. “Pharmacologically active” (or simply “active”), as in a “pharmacologically active” derivative or analog, can refer to a derivative or analog (e.g., a salt, ester, amide, conjugate, metabolite, isomer, fragment, etc.) having the same type of pharmacological activity as the parent compound and approximately equivalent in degree. “Therapeutic agent” refers to any composition that has a beneficial biological effect. Beneficial biological effects include both therapeutic effects, e.g., treatment of a disorder or other undesirable physiological condition, and prophylactic effects, e.g., prevention of a disorder or other undesirable physiological condition (e.g., a non- immunogenic cancer). The terms also encompass pharmaceutically acceptable, pharmacologically active derivatives of beneficial agents specifically mentioned herein, including, but not limited to, salts, esters, amides, proagents, active metabolites, isomers, fragments, analogs, and the like. When the terms “therapeutic agent” is used, then, or when a particular agent is specifically identified, it is to be understood that the term includes the agent per se as well as pharmaceutically acceptable, pharmacologically active salts, esters, amides, proagents, conjugates, active metabolites, isomers, fragments, analogs, etc. “Therapeutically effective amount” or “therapeutically effective dose” of a composition (e.g. a composition comprising an agent) refers to an amount that is effective to achieve a desired therapeutic result. In some embodiments, a desired therapeutic result is the control of an infection. Therapeutically effective amounts of a given therapeutic agent will typically vary with respect to factors such as the type and severity of the disorder or disease being treated and the age, gender, and weight of the subject. The term can also refer to an amount of a therapeutic agent, or a rate of delivery of a therapeutic agent (e.g., amount over time), effective to facilitate a desired therapeutic effect, such as pain relief. The precise desired therapeutic effect will vary according to the condition to be treated, the tolerance of the subject, the agent and / or agent formulation to be administered (e.g., the potency of the therapeutic agent, theAttorney Docket No.3289.0009WO concentration of agent in the formulation, and the like), and a variety of other factors that are appreciated by those of ordinary skill in the art. In some instances, a desired biological or medical response is achieved following administration of multiple dosages of the composition to the subject over a period of days, weeks, or years. “Vaccine” as used herein is a preparation that stimulates an immune response that produces immunity against a particular antigen or antigens, e.g. a component of a gram-negative bacteria. Vaccines can be administered prophylactically (for example, to prevent or inhibit the establishment of an infection) or therapeutically (e.g., to inhibit, reduce, or treat an established infection, or to ameliorate the effects or symptoms of an existing infection). Vaccines can contain, but are not limited to, live, attenuated infectious material such as viruses or bacteria, and dead or inactivated organisms or purified products or fragments derived therefrom. In some embodiments, the vaccine of the presently disclosed subject matter comprises a “subunit vaccine”, i.e., a vaccine comprising purified fragments from a pathogen. In some embodiments, the vaccine comprises an antigenic fusion polypeptide. A vaccine can be administered by injection (e.g., subcutaneous (sc), intramuscular (im), intraperitoneal (ip), intradermal (id) or intravenous (iv) injection), orally, or by inhalation. The term “fusion” as used herein with reference to polypeptides and portions of polypeptides that are “fused” together means that the amino acid sequences are covalently joined to each other, e.g., by peptide bonds, directly or via a linking amino acid sequence. As used throughout, the term “fusion protein” or “fusion polypeptide” refers to a non-naturally occurring protein or polypeptide, e.g., a protein or polypeptide having an amino acid sequence comprising at least two partial or complete sequences derived from, obtained from, or isolated from different polypeptides that are not naturally adjoined. A fusion protein or fusion polypeptide can be the functional product of a fusion gene or fusion nucleic acid sequence. A fusion gene can further be modified by mutation, deletion, insertion or substitution of heterologous sequences, or by any means available using recombinant DNA technology. As used throughout, the term “fragment” refers to a peptide or polypeptide of formed by at least 6 amino acid residues which are linked to each other via peptide bonds, but which contains less amino acid residues (e.g., 5 less, 10 less, 20 less, 30Attorney Docket No.3289.0009WO less, 40 less amino acid residues) than a recited “parent” polypeptide. In the context of the presently disclosed subject matter, an “antigenic fragment” is a peptide or polypeptide capable of eliciting an immune response, including the production of antibodies directed to that immunogenic fragment or to the protein having the immunogenic fragment. For example, an antigenic fragment of the needle tip protein PcrV has the ability to elicit the production of antibodies against PcrV. As used throughout, the terms “antibody” and “immunoglobulin” refer to a protein produced by the B-cells of the immune system that can identify, bind and neutralize an antigen. In the context of the presently disclosed subject matter, an antibody is produced by the immune system and binds a bacterial protein, e.g., such as PcrV or PopB. The antibody can have neutralizing properties and be capable of suppressing or reducing the biological activity of the bacterial protein. As used throughout, the term “active immunization” refers to immunization that stimulates the immune system to produce antibodies against an antigen (self or foreign). Active immunization can be induced through vaccination. Active immunization is often long-lasting and can be reactivated by repeated injection of boosters. In contrast, passive immunization occurs when antibodies directed against specific antigen are administered to a subject. As used throughout, the term “adjuvant” refers to a substance that increases the intensity of the immune response after co-administration with an immunogen. An adjuvant can act as an immunopotentiator, e.g., providing for more potent and / or persistent immune responses, while reducing the dose and number of boosters. Adjuvant can also increase the stability of the immunogenic composition or vaccine. II. Methods of Preventing and / or Reducing Infections In some embodiments, the presently disclosed subject matter provides a vaccine to protect against PA and / or SA infections, particularly in subjects with pre- exposure to SA and / or that are at high risk of developing PA and / or SA infections (e.g., CF patients). In some embodiments, the vaccine is a bivalent vaccine comprising: (a) a fusion polypeptide comprising (1) a fusion of a needle tip protein or an antigenic fragment thereof and / or a translocator protein or an antigenic fragment thereof from a Type III secretion system (T3SS) of PA and (2) the A1 subunit of the labile toxin (LTA1) from enterotoxigenic Escherichia coli; and (b) a polypeptideAttorney Docket No.3289.0009WO comprising the NEAr transporter 2 domain (NEAT2) of iron-regulated surface determinant protein B (IsdB), wherein the polypeptide comprising NEAT2 has an amino acid sequence of SEQ ID NO: 11, or a polypeptide having at least 90% homology to SEQ ID NO: 11 (e.g., at least 90%, at least 95%, at least 98%, at least 99%, or at least 99.5% homology to SEQ ID NO: 11). In some embodiments the vaccine comprises: (a) a fusion polypeptide comprising (1) a fusion of a needle tip protein or an antigenic fragment thereof and a translocator protein or an antigenic fragment thereof from a T3SS of PA and (2) LTA1 from enterotoxigenic Escherichia coli; and (b) a polypeptide comprising NEAT2 of IsdB, wherein the polypeptide comprising NEAT2 has an amino acid sequence of SEQ ID NO: 11, or a polypeptide having at least 90% homology to SEQ ID NO: 11 (e.g., at least 90%, at least 95%, at least 98%, at least 99%, or at least 99.5% homology to SEQ ID NO: 11). For example, in some embodiments, the fusion of the needle tip protein or antigenic fragment thereof and the translocator protein or antigenic fragment thereof can be the fusion referred to as PaF, which is a fusion of the needle tip protein PcrV (which has the amino acid sequence of SEQ ID NO: 8) and the translocator protein PopB (which has the amino acid sequence of SEQ ID NO: 10). These two surface localized T3SS scaffold proteins are highly conserved (>96-99%) among PAO1 / PA14-like strains of PA. Because these proteins are involved in the early stages of pathogenesis for PAO1 / PA14-like strains, vaccine escape is unlikely since mutation of these proteins impacts assembly of the T3SS apparatus, rendering the mutant non-pathogenic. In some embodiments, PaF refers to the polypeptide having the amino acid sequence of SEQ ID NO: 2 or the amino acid sequence encoded by the nucleic acid sequence of SEQ ID NO: 1. In some embodiments, the vaccine comprises a fusion comprising an amino acid sequence of PcrV (SEQ ID NO: 8) or a sequence having at least 50%, at least 60%, at least 70%, at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, at least 99%, or at least 99.5% homology to the amino acid sequence SEQ ID NO: 8. In some embodiments, the fusion comprises an amino acid sequence of PopB (SEQ ID NO: 10) or a sequence having at least 50%, at least 60%, at least 70%, at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, at least 99%, or at least 99.5% homology to the amino acid sequence of SEQ ID NO: 10. In some embodiments, the fusion comprises an amino acid sequence of PaF (SEQ ID NO: 2) or a sequenceAttorney Docket No.3289.0009WO having at least 50%, at least 60%, at least 70%, at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, at least 99%, or at least 99.5% homology to SEQ ID NO: 2. In some embodiments, the LTA1 subunit from the labile toxin (LT) of enterotoxigenic E. coli (which has the amino acid sequence of SEQ ID NO: 6) serves as the adjuvant of the presently disclosed vaccine. LTA1 retains the toxin's ADP- ribosylation (ADPr) activity and the ability to promote dendritic cell (DC) maturation but does not possess detectable toxicity. LTA1 stimulates a balanced Th1 / Th2 response along with a mucosal response characterized by production of mucosal IgA, as well as IL-17. In some embodiments, LTA1 is fused to the N-terminus of the PaF polypeptide to provide the fusion polypeptide LTA1-PaF (also referred to herein as “L-PaF”, and which has the amino acid sequence of SEQ ID NO: 4), thus providing simultaneous uptake of the adjuvant-antigen by antigen presenting cells to enhance cellular immunity. The L-PaF vaccine was previously described in PCT International Publication Number WO 2022 / 246327 (PCT / US2022 / 030565), the disclosure of which is incorporated herein by reference in its entirety. In some embodiments, the fusion polypeptide comprises an amino acid sequence of PcrV (SEQ ID NO: 8) or a sequence having at least 50%, at least 60%, at least 70%, at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, at least 99%, or at least 99.5% homology to SEQ ID NO: 8. In some embodiments, the fusion polypeptide comprises an amino acid sequence of PopB (SEQ ID NO: 10) or a sequence having at least 50%, at least 60%, at least 70%, at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, at least 99%, or at least 99.5% homology to SEQ ID NO: 10. In some embodiments, the fusion polypeptide comprises an amino acid sequence of PaF (SEQ ID NO: 2) or a sequence having at least 50%, at least 60%, at least 70%, at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, at least 99%, or at least 99.5% homology to SEQ ID NO: 2. In some embodiments, the fusion polypeptide comprises an amino acid sequence of LTA1 (SEQ ID NO: 6) or a sequence having at least 50%, at least 60%, at least 70%, at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, or at least 99% homology to SEQ ID NO: 6. In some embodiments, the fusion polypeptide comprises an amino acid sequence of L-PaF (SEQ ID NO: 4) or a sequence having at least 50%, at least 60%, at least 70%,Attorney Docket No.3289.0009WO at least 80%, at least 85%, at least 90%, at least 95%, at least 98%, at least 99%, or at least 99.5% homology to SEQ ID NO: 4. According to the presently disclosed subject matter, the L-PaF vaccine can be provided in a formulation together with a peptide comprising NEAT2 or a peptide comprising a sequence with at least 90% homology to NEAT2. This bivalent vaccine can be referred to as L-PaF / N2. Accordingly, in some embodiments, the presently disclosed subject matter provides a method for preventing and / or substantially reducing a PA and / or SA infection in a subject in need thereof, wherein the method comprises comprising administering to the subject a therapeutically effective amount of a vaccine comprising (a) a fusion polypeptide wherein the fusion polypeptide comprises i) a fusion of a needle tip protein or an antigenic fragment thereof and / or a translocator protein or an antigenic fragment thereof from a T3SS of Pa and ii) LTA1 from enterotoxigenic Escherichia coli; and (b) NEAT2 (SEQ ID NO: 11) or a polypeptide having at least 90% homology to NEAT2 (SEQ ID NO: 11) . In some embodiments, the subject is a mammal. In some embodiments, the subject is a human. In some embodiments, the subject has CF. In some embodiments, the subject is a subject with a prior history of exposure to PA and / or SA (e.g., MRSA) or who has a history associated with suspected exposure to PA and / or SA (e.g., prior hospitalization). Thus, in some embodiments, the subject is a subject that was exposed to SA (e.g., MRSA) or suspected of being exposed to SA prior to the administration of the vaccine disclosed herein. In some embodiments, the infection being prevented and / or substantially reduced is a MRSA infection. In some embodiments, the fusion of the needle tip protein or the antigenic fragment thereof and / or the translocator protein or the antigenic fragment thereof from the T3SS of PA is a polypeptide comprising an amino acid sequence of PcrV (SEQ ID NO: 8) or an amino acid sequence having at least about 90% (e.g., at least 90%, 91%, 92%, 93%, 94%, 95%, 98%, 99%, or 99.5%) homology thereto. In some embodiments, the fusion of the needle tip protein or the antigenic fragment thereof and / or the translocator protein or the antigenic fragment thereof from the T3SS of PA is a polypeptide comprising an amino acid sequence of PopB (SEQ ID NO: 10) or an amino acid sequence having at least about 90% (e.g., at least 90%, 91%, 92%, 93%,Attorney Docket No.3289.0009WO 94%, 95%, 98%, 99%, or 99.5%) homology thereto. In some embodiments, the fusion of the needle tip protein or the antigenic fragment thereof and / or the translocator protein or the antigenic fragment thereof from the T3SS of PA is a polypeptide having an amino acid sequence of SEQ ID NO: 2 (PaF) or an amino acid sequence having at least 90% (e.g., at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 99.5%) homology to the amino acid sequence of SEQ ID NO: 2. In some embodiments, the LTA1 is 5’ of the fusion of the needle tip protein or an antigenic fragment thereof and / or the translocator protein fusion or an antigenic fragment thereof. In some embodiments, the LTA1 has an amino acid sequence of SEQ ID NO: 6, or an amino acid sequence having at least 90% (e.g., 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99%) homology to the amino acid sequence of SEQ ID NO: 6. In some embodiments, the fusion polypeptide has an amino acid sequence of SEQ ID NO: 4 (L-PaF), or an amino acid sequence having at least 90% (e.g., 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 99.5%) homology to SEQ ID NO: 4. In some embodiments, the vaccine comprises a protein comprising or consisting of NEAT2, i.e., a protein having the amino acid sequence of SEQ ID NO: 11. In some embodiments, the vaccine comprises or consists of a protein comprising or consisting of an amino acid sequence having at least 95%, 96%, 97%, 98%, or 99% homology to SEQ ID NO: 11. In some embodiments, the vaccine comprises (e.g., the fusion polypeptide is formulated as) an emulsion, e.g., a microemulsion (e.g., containing dispersed droplets having a diameter of about 5 micrometers (μm) to about 50 μm) or nanoemulsion (e.g., containing dispersed droplets having a diameter of about 20 nanometers (nm) to about 100 nm). In some embodiments, the emulsion is an oil-in-water emulsion. In some embodiments, the emulsion (e.g., the microemulsion) comprises squalene. In some embodiments, the vaccine comprises MedImmune Emulsion (ME), i.e., an emulsion comprising Histidine, sucrose, squalene, and polysorbate-80 (PS80). In some embodiments, the emulsion comprises about 10 millimolar (mM) Histidine, about 5% sucrose, about 2% squalene, and about 0.5% polysorbate-80 (PS80), and having a pH of about 6. When the L-PaF / N2 vaccine comprises an ME emulsion, the vaccine can be referred to as “the L-PaF / ME / N2 vaccine.”Attorney Docket No.3289.0009WO The vaccine can be administered via any convenient route, e.g., orally, by injection or intravenously, or intranasally. In some embodiments, the vaccine is administered via injection. In some embodiments, the vaccine is administered intranasally (IN). In some embodiments, the vaccine can be injected directly into a body cavity or the site of a wound (e.g., a surgical wound). The vaccine (e.g., the L-PaF / N2 or L-PaF / ME / N2 vaccine) can be administered a single time or multiple times. In some embodiments, the vaccine is administered multiple times to the same subject. Thus, “prime-boost” regimens can be used according to the presently disclosed subject matter The first administration of the vaccine can be referred to as a “prime” or “priming” dose, while subsequent administrations can be referred to as “boosts”. Separate administrations of the vaccine are typically separated by an intervening period of at least about one week or more (e.g., about two weeks, about three weeks, about four weeks, about five weeks, about six weeks, etc.). In some embodiments, separate administrations can be separated by an intervening period of one or more months (e.g., about 1 month to about 12 months) or one or more years (e.g., about 2 years to about 10 years). A typical regimen can comprise an immunization followed by booster administration (e.g. by injection) at regular time intervals, such as 2-, 3-, 4-, or 6-week intervals. However, less regular booster administration, such as annual boosting can be performed for reasons of convenience and compliance. Alternatively, booster injections can be on an irregular basis as indicated by monitoring of immune response (e.g. when the level of the antibodies is below a threshold determined by a doctor or a person skilled in the art). In some embodiments, the vaccine (e.g., the L-PaF / N2 or L-PaF / ME / N2 vaccine) is administered one time. In some embodiments, the vaccine (e.g., the L- PaF / N2 or L-PaF / ME / N2 vaccine) is administered to the subject at least two times. In some embodiments, the vaccine is administered to the subject two times. In some embodiments, the vaccine is administered to the subject three times. In some embodiments, the vaccine doses are administered about two weeks apart. In some embodiments, the vaccine (e.g., the L-PaF / N2 or L-PAF / ME / N2 vaccine) can be administered with any other suitable therapeutic component, including but not limited to a biologic (e.g. antibody, peptide, blood, blood components, allergenics, somatic cells, gene therapy, tissues, and recombinant therapeutic proteins), or small molecule drugs or low molecular weight compounds.Attorney Docket No.3289.0009WO In some embodiments, the vaccine can be provided in a composition comprising an adjuvant (i.e., an adjuvant in addition to the LTA1 present in the fusion polypeptide). For example, in some embodiments, the adjuvant is cholera toxin or a pertussis toxoid (Ptd). In some embodiments, the adjuvant is a Toll-like receptor 4 (TLR4) agonist. In some embodiments, the TLR4 agonist is a modified lipopolysaccharide (LPS) or lipooligosaccharide (LOS). In some embodiments, the TLR4 agonist is Lipid A mimetic. Lipid A mimetics include, for example, monophosphoryl lipid A (MPL) and aminoalkyl glucosaminide phosphates (AGPs). In some embodiments, the Lipid A mimetic is a modified LPS or modified LOS such as a Bacterial Enzymatic Combinatorial Chemistry (BECC) candidate described in U.S. Patent No. 11,124,815, the disclosure of which in incorporated herein by reference in its entirety. In some embodiments, the adjuvant is Bacterial Enzymatic Combinatorial Chemistry candidate 438 (hereafter referred to as BECC438), a TLR- 4 agonist that is a biosimilar of monophosphoryl lipid A (MPL), which is approved for use in some human vaccines. BECC438 is a bis-phosphorylated hexa-acylated lipid A prepared from specifically engineered strains of Yersinia pestis. See Figure 11. In some embodiments, the SA and / or PA is substantially or entirely prevented in the subject. By “substantially prevented” is meant that exposure of a vaccinated subject can result in a significantly lower bacterial load compared to the bacterial load of an unvaccinated subject at the same level of exposure. For example, the vaccinated subject can have a bacterial load that is about 25% or less, about 20% or less, about 15% or less, or about 10% or less compared to an unvaccinated subject after exposure of both the vaccinated and unvaccinated subject to the same level of bacteria. In some embodiments, the bacterial load can be quantified as colony forming units (CFUs) per organ or tissue volume. In some embodiments, administering the vaccine elicits opsonophagocytic killing (OPK) activity and / or elevated levels of secreted IL-17. By “elevated levels” is meant that the amount of IL-17 is above the amount of IL-17 seen in an unvaccinated subject. In some embodiments, the vaccine elicits OPK activity and elevated levels of secreted IL-17. In some embodiments, the administering elicits elevated levels of secreted IL-17 from lung cells. In some embodiments, theAttorney Docket No.3289.0009WO administering produces a response to PA and / or SA that includes a cell-mediated response to eliminate SA and / or PA. In some embodiments, the presently disclosed subject matter provides a vaccine formulation for use in preventing and / or reducing a PA and / or a SA infection in a subject, wherein the vaccine formulation comprises: (a) a fusion polypeptide, wherein the fusion polypeptide comprises i) a fusion of a needle tip protein or an antigenic fragment thereof and / or a translocator protein or an antigenic fragment thereof from a T3SS of PA, and ii) an LTA1 from enterotoxigenic Escherichia coli; and (b) a polypeptide comprising NEAT2 from IsdB, wherein the polypeptide comprising NEAT2 has an amino acid sequence of SEQ ID NO: 11, or a polypeptide having at least 90% homology to SEQ ID NO: 11. In some embodiments, the fusion polypeptide comprises the amino acid sequence of LTA1 (SEQ ID NO: 6) or an amino acid sequence having at least about 90% homology thereto. In some embodiments, the fusion polypeptide comprises the amino acid sequence of PcrV (SEQ ID NO: 8) or an amino acid sequence having at least about 90% homology thereto. In some embodiments, the fusion polypeptide comprises the amino acid sequence of PopB (SEQ ID NO: 10) or an amino acid sequence having at least about 90% homology thereto. In some embodiments, the fusion polypeptide comprises the amino acid sequence of PaF (SEQ ID NO: 2) or an amino acid sequence having at least about 90% homology thereto. In some embodiments, the fusion polypeptide comprises L-PaF (i.e., SEQ ID NO: 4) or an amino acid having at least 90% homology to SEQ ID NO: 4. In some embodiments, the fusion polypeptide comprises an amino acid sequence having at least 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 99.5% homology to SEQ ID NO: 4. In some embodiments, the vaccine formulation comprises a protein comprising or consisting of NEAT2 (i.e., the amino acid sequence of SEQ ID NO: 11). In some embodiments, the vaccine formulation comprises a protein comprising or consisting of an amino acid sequence having at least 95%, 96%, 97%, 98%, or 99% homology to SEQ ID NO: 11. In some embodiments, the vaccine formulation comprises a nanoemulsion or a microemulsion. In some embodiments, the vaccine formulation comprises an oil- in-water emulsion (e.g., a squalene-based oil-in-water emulsion). In some embodiments, the vaccine formulation comprises L-PaF / ME / N2. In someAttorney Docket No.3289.0009WO embodiments, the vaccine formulation further comprises an adjuvant (i.e., in addition to the LTA1 present in the fusion polypeptide). In some embodiments, the adjuvant comprises a TLR4 agonist, such as a lipid A mimetic. In some embodiments, the TLR4 agonist is BECC438. In some embodiments, the vaccine formulation is for use in preventing or reducing a SA infection. In some embodiments, the SA infection is a MRSA infection. In some embodiments, the vaccine formulation provide protection against PA and / or SA infection in a subject with a prior history of exposure to SA (e.g., MRSA). Thus, in some embodiments, the vaccine formulation provides protection against development of a PA and / or SA infection in a patient who is re-exposed (or newly exposed) to PA and / or SA after treatment or recovery from a previous PA and / or SA infection or in a patient who has a medical history of PA and / or SA infection or who was previously at risk of a PA and / or SA infection (e.g., a patient with a history of hospitalization and / or CF). In some embodiments, the vaccine is effective in a subject that has CF. In some embodiments, the vaccine formulation elicits OPK activity and / or elevated levels of secreted IL-17. In some embodiments, the elevated levels of secreted IL-17 are in lung cells of a subject treated with the vaccine formulation. In some embodiments, administration of the vaccine formulation to a subject substantially or entirely prevents a PA and / or SA infection in a subject. The vaccine formulation can be formulated for administration to a subject via any suitable route. In some embodiments, the vaccine formulation is formulated for administration to a subject via a route selected from intravenous, oral and inhalation. In some embodiments, the vaccine formulation is formulated for injection to a wound site. III. Polypeptides As will be understood by one of ordinary skill in the art, in some embodiments, the presently disclosed subject matter relates to methods comprising the administration of polypeptides. In some embodiments, the polypeptides can be prepared via chemical synthesis, according to methods known in the field. In some embodiments, the polypeptides are recombinant polypeptides. Thus, in someAttorney Docket No.3289.0009WO embodiments, the presently disclosed subject matter relates to recombinant polypeptides and the nucleic acids encoding the polypeptides. For example, in some embodiments, the polynucleotides disclosed herein can be introduced into an expression vector, such that the expression vector comprises a promoter and the polynucleotides encoding the peptides or polypeptides described herein. The expression vector can provide for expression of the peptides or polypeptides in a suitable expression system using techniques well known in the art, followed by isolation or purification of the expressed peptide or polypeptide of interest. A variety of bacterial, yeast, plant, mammalian, and insect expression systems are available in the art and any such expression system can be used. Alternatively, a polynucleotide encoding a peptide of use herein can be translated in a cell-free translation system. Exemplary nucleic acid and amino acid sequences described herein are as follows: PaF nucleic acid sequence (SEQ ID NO: 1): CATATGGAAGTCAGAAACCTTAATGCCGCTCGCGAGCTGTT CCTGGACGAGCTCCTGGCCGCGTCGGCGGCGCCTGCCAGT GCCGAGCAGGAGGAACTGCTGGCCCTGTTGCGCAGCGAGC GGATCGTGCTGGCCCACGCCGGCCAGCCGCTGAGCGAGGC GCAAGTGCTCAAGGCGCTCGCCTGGTTGCTCGCGGCCAATC CGTCCGCGCCTCCGGGGCAGGGCCTCGAGGTACTCCGCGA AGTCCTGCAGGCACGTCGGCAGCCCGGTGCGCAGTGGGAT CTGCGTGAGTTCCTGGTGTCGGCCTATTTCAGCCTGCACGG GCGTCTCGACGAGGATGTCATCGGTGTCTACAAGGATGTCC TGCAGACCCAGGACGGCAAGCGCAAGGCGCTGCTCGACGA GCTCAAGGCGCTGACCGCGGAGTTGAAGGTCTACAGCGTG ATCCAGTCGCAGATCAACGCCGCGCTGTCGGCCAGGCAGG GCATCAGGATCGACGCTGGCGGTATCGATCTGGTCGACCCC ACGCTATATGGCTATGCCGTCGGCGATCCCAGGTGGAAGG ACAGCCCCGAGTATGCGCTGCTGAGCAATCTGGATACCTTC AGCGGCAAGCTGTCGATCAAGGATTTTCTCAGCGGCTCGCC GAAGCAGAGCGGGGAACTCAAGGGCCTCAGCGATGAGTAC CCCTTCGAGAAGGACAACAACCCGGTCGGCAATTTCGCCAAttorney Docket No.3289.0009WO CCACGGTGAGCGACCGCTCGCGTCCGCTGAACGACAAGGT CAACGAGAAGACCACCCTGCTCAACGACACCAGCTCCCGC TACAACTCGGCGGTCGAGGCGCTCAACCGCTTCATCCAGA AATACGACAGCGTCCTGAGCGACATTCTCAGCGCGATCGG ATCCATGAACCCGATTACGCTGGAACGTGCTGGTCTGCCGT ATGGTGTTGCCGATGCTGGTGACATCCCGGCTCTGGGTCGC CCGGTCGCACGTGATGTGGAAAGTCTGCGTGTTGAACGTCT GGCAGCACCGGCAGCTGCAAGCGCATCTGGCACCGGTGTC GCTCTGACGCCGCCGTCTGCAGCAAGTCAGCAACGTCTGG AAGTTGCTAACCGCGCGGAAATTGCCTCACTGGTCCAGGC AGTGGGTGAAGACGTGGGTCTGGCACGTCAAGTGGTTCTG GCAGGTGCATCGACCCTGCTGAGCGCAGGTCTGATGTCGCC GCAGGCGTTCGAAATTGAACTGGCCAAAATCACCGGCGAA GTTGAAAATCAGCAGAAAAAACTGAAACTGACGGAAATCG AACAGGCCCGTAAACAGAACCTGCAAAAAATGGAAGATAA CCAGCAAAAAATCCGCGAATCGGAAGAAGCTGCGAAAGA AGCGCAGAAAAGCGGCCTGGCCGCAAAAATTTTTGGTTGG ATTTCTGCTATCGCGAGTATTATCGTGGGTGCAATCATGGT TGCAACCGGTGTCGGTGCTGCAGCAGGTGCACTGATGATTG CTGGCGGTGTCATGGGTGTCGTGAGTCAGTCCGTGCAGCAA GCAGCTGCGGATGGTCTGATCTCAAAAGAAGTGATGGAAA AACTGGGCCCGGCCCTGATGGGTATTGAAATGGCCGTGGC ACTGCTGGCCGCAGTTGTCTCCTTTGGTGGTTCAGCAGTTG GTGGTCTGGCACGTCTGGGTGCAAAAATCGGCGGTAAAGC TGCGGAAATGACGGCATCCCTGGCTTCAAAAGTGGCAGAC CTGGGCGGTAAATTCGGCTCTCTGGCGGGCCAGTCACTGTC GCATAGCCTGAAACTGGGTGTGCAAGTTTCTGATCTGACCC TGGACGTTGCAAACGGCGCCGCACAGGCTACGCACAGTGG TTTTCAAGCGAAAGCTGCGAATCGTCAGGCCGATGTTCAAG AATCCCGTGCAGACCTGACCACGCTGCAGGGTGTCATTGA ACGTCTGAAAGAAGAACTGAGCCGCATGCTGGAAGCCTTT CAGGAAATTATGGAACGCATCTTCGCAATGCTGCAAGCGAAttorney Docket No.3289.0009WO AAGGCGAAACCCTGCACAATCTGTCTTCCCGTCCGGCGGCT ATCTGAGGATCC PaF amino acid sequence (SEQ ID NO: 2): MEVRNLNAARELFLDELLAASAAPASAEQEELLALLRSERIVL AHAGQPLSEAQVLKALAWLLAANPSAPPGQGLEVLREVLQA RRQPGAQWDLREFLVSAYFSLHGRLDEDVIGVYKDVLQTQD GKRKALLDELKALTAELKVYSVIQSQINAALSARQGIRIDAGG IDLVDPTLYGYAVGDPRWKDSPEYALLSNLDTFSGKLSIKDFL SGSPKQSGELKGLSDEYPFEKDNNPVGNFATTVSDRSRPLND KVNEKTTLLNDTSSRYNSAVEALNRFIQKYDSVLSDILSAIGS MNPITLERAGLPYGVADAGDIPALGRPVARDVESLRVERLAA PAAASASGTGVALTPPSAASQQRLEVANRAEIASLVQAVGED VGLARQVVLAGASTLLSAGLMSPQAFEIELAKITGEVENQQK KLKLTEIEQARKQNLQKMEDNQQKIRESEEAAKEAQKSGLAA KIFGWISAIASIIVGAIMVATGVGAAAGALMIAGGVMGVVSQS VQQAAADGLISKEVMEKLGPALMGIEMAVALLAAVVSFGGS AVGGLARLGAKIGGKAAEMTASLASKVADLGGKFGSLAGQS LSHSLKLGVQVSDLTLDVANGAAQATHSGFQAKAANRQADV QESRADLTTLQGVIERLKEELSRMLEAFQEIMERIFAMLQAKG ETLHNLSSRPAAI LTA1-PaF (L-PaF) nucleic acid sequence (SEQ ID NO: 3): CATatggacaatggcgatcgtttataccgtgccgactcgcgtcccccagatgagattaaacgta gcggtgggttaatgccacgtgggcacaatgagtattttgaccgtggaacacagatgaacattaacc tttacgatcatgcccgtgggacccagaccgggtttgtccgttatgatgacgggtatgttagtacgag tttgtccttacgctccgcacaccttgcgggacaaagtattttatcaggctacagcacatattacatttat gtgatcgccactgccccaaacatgttcaatgtgaacgatgtgttgggggtttacagcccccatccat atgaacaagaagtctcggcccttggggggatcccatatagccagatttatggttggtaccgcgtaa attttggtgtgattgatgaacgtttgcatcgtaaccgtgaataccgcgatcgctactaccgtaacttga acattgcacctgccgaggacggctatcgtttagcgggattcccacccgatcatcaggcgtggcgt gaggaaccgtggatccatcacgcccctcaggggtgcgggaacagtagtcgcCATATGGA AGTCAGAAACCTTAATGCCGCTCGCGAGCTGTTCCTGGACGAttorney Docket No.3289.0009WO AGCTCCTGGCCGCGTCGGCGGCGCCTGCCAGTGCCGAGCA GGAGGAACTGCTGGCCCTGTTGCGCAGCGAGCGGATCGTG CTGGCCCACGCCGGCCAGCCGCTGAGCGAGGCGCAAGTGC TCAAGGCGCTCGCCTGGTTGCTCGCGGCCAATCCGTCCGCG CCTCCGGGGCAGGGCCTCGAGGTACTCCGCGAAGTCCTGC AGGCACGTCGGCAGCCCGGTGCGCAGTGGGATCTGCGTGA GTTCCTGGTGTCGGCCTATTTCAGCCTGCACGGGCGTCTCG ACGAGGATGTCATCGGTGTCTACAAGGATGTCCTGCAGAC CCAGGACGGCAAGCGCAAGGCGCTGCTCGACGAGCTCAAG GCGCTGACCGCGGAGTTGAAGGTCTACAGCGTGATCCAGT CGCAGATCAACGCCGCGCTGTCGGCCAGGCAGGGCATCAG GATCGACGCTGGCGGTATCGATCTGGTCGACCCCACGCTAT ATGGCTATGCCGTCGGCGATCCCAGGTGGAAGGACAGCCC CGAGTATGCGCTGCTGAGCAATCTGGATACCTTCAGCGGCA AGCTGTCGATCAAGGATTTTCTCAGCGGCTCGCCGAAGCAG AGCGGGGAACTCAAGGGCCTCAGCGATGAGTACCCCTTCG AGAAGGACAACAACCCGGTCGGCAATTTCGCCACCACGGT GAGCGACCGCTCGCGTCCGCTGAACGACAAGGTCAACGAG AAGACCACCCTGCTCAACGACACCAGCTCCCGCTACAACTC GGCGGTCGAGGCGCTCAACCGCTTCATCCAGAAATACGAC AGCGTCCTGAGCGACATTCTCAGCGCGATCGGATCCATGA ACCCGATTACGCTGGAACGTGCTGGTCTGCCGTATGGTGTT GCCGATGCTGGTGACATCCCGGCTCTGGGTCGCCCGGTCGC ACGTGATGTGGAAAGTCTGCGTGTTGAACGTCTGGCAGCA CCGGCAGCTGCAAGCGCATCTGGCACCGGTGTCGCTCTGAC GCCGCCGTCTGCAGCAAGTCAGCAACGTCTGGAAGTTGCT AACCGCGCGGAAATTGCCTCACTGGTCCAGGCAGTGGGTG AAGACGTGGGTCTGGCACGTCAAGTGGTTCTGGCAGGTGC ATCGACCCTGCTGAGGGCAGGTCTGATGTCGCCGCAGGCG TTCGAAATTGAACTGGCCAAAATCACCGGCGAAGTTGAAA ATCAGCAGAAAAAACTGAAACTGACGGAAATCGAACAGGC CCGTAAACAGAACCTGCAAAAAATGGAAGATAACCAGCAA AAAATCCGCGAATCGGAAGAAGCTGCGAAAGAAGCGCAGAttorney Docket No.3289.0009WO AAAAGCGGCCTGGCCGCAAAAATTTTTGGTTGGATTTCTGC TATCGCGAGTATTATCGTGGGTGCAATCATGGTTGCAACCG GTGTCGGTGCTGCAGCAGGTGCACTGATGATTGCTGGCGGT GTCATGGGTGTCGTGAGTCAGTCCGTGCAGCAAGCAGCTG CGGATGGTCTGATCTCAAAAGAAGTGATGGAAAAACTGGG CCCGGCCCTGATGGGTATTGAAATGGCCGTGGCACTGCTGG CCGCAGTTGTCTCCTTTGGTGGTTCAGCAGTTGGTGGTCTG GCACGTCTGGGTGCAAAAATCGGCGGTAAAGCTGCGGAAA TGACGGCATCCCTGGCTTCAAAAGTGGCAGACCTGGGCGG TAAATTCGGCTCTCTGGCGGGCCAGTCACTGTCGCATAGCC TGAAACTGGGTGTGCAAGTTTCTGATCTGACCCTGGACGTT GCAAACGGCGCCGCACAGGCTACGCACAGTGGTTTTCAAG CGAAAGCTGCGAATCGTCAGGCCGATGTTCAAGAATCCCG TGCAGACCTGACCACGCTGCAGGGTGTCATTGAACGTCTGA AAGAAGAACTGAGCCGCATGCTGGAAGCCTTTCAGGAAAT TATGGAACGCATCTTCGCAATGCTGCAAGCGAAAGGCGAA ACCCTGCACAATCTGTCTTCCCGTCCGGCGGCTATCTGAGG ATCC LTA1-PaF (L-PaF) amino acid sequence (SEQ ID NO: 4): MDNGDRLYRADSRPPDEIKRSGGLMPRGHNEYFDRGTQMNI NLYDHARGTQTGFVRYDDGYVSTSLSLRSAHLAGQSILSGYS TYYIYVIATAPNMENVNDVLGVYSPHPYEQEVSALGGIPYSQI YGWYRVNFGVIDERLHRNREYRDRYYRNLNIAPAEDGYRLA GFPPDHQAWREEPWIHHAPQGCGNSSRMEVRNLNAARELFL DELLAASAAPASAEQEELLALLRSERIVLAHAGQPLSEAQVLK ALAWLLAANPSAPPGQGLEVLREVLQARRQPGAQWDLREFL VSAYFSLHGRLDEDVIGVYKDVLQTQDGKRKALLDELKALT AELKVYSVIQSQINAALSARQGIRIDAGGIDLVDPTLYGYAVG DPRWKDSPEYALLSNLDTFSGKLSIKDFLSGSPKQSGELKGLS DEYPFEKDNNPVGNFATTVSDRSRPLNDKVNEKTTLLNDTSS RYNSAVEALNRFIQKYDSVLSDILSAIGSMNPITLERAGLPYGV ADAGDIPALGRPVARDVESLRVERLAAPAAASASGTGVALTPAttorney Docket No.3289.0009WO PSAASQQRLEVANRAEIASLVQAVGEDVGLARQVVLAGASTL LSAGLMSPQAFEIELAKITGEVENQQKKLKLTEIEQARKQNLQ KMEDNQQKIRESEEAAKEAQKSGLAAKIFGWISAIASIIVGAI MVATGVGAAAGALMIAGGVMGVVSQSVQQAAADGLISKEV MEKLGPALMGIEMAVALLAAVVSFGGSAVGGLARLGAKIGG KAAEMTASLASKVADLGGKFGSLAGQSLSHSLKLGVQVSDL TLDVANGAAQATHSGFQAKAANRQADVQESRADLTTLQGVI ERLKEELSRMLEAFQEIMERIFAMLQAKGETLHNLSSRPAAI LTA1 nucleic acid sequence (SEQ ID NO: 5): CATAtggacaatggcgatcgtttataccgtgccgactcgcgtcccccagatgagattaaacgta gcggtgggttaatgccacgtgggcacaatgagtattttgaccgtggaacacagatgaacattaacc tttacgatcatgcccgtgggacccagaccgggtttgtccgttatgatgacgggtatgttagtacgag tttgtccttacgctccgcacaccttgcgggacaaagtattttatcaggctacagcacatattacatttat gtgatcgccactgccccaaacatgttcaatgtgaacgatgtgttgggggtttacagcccccatccat atgaacaagaagtctcggcccttggggggatcccatatagccagatttatggttggtaccgcgtaa attttggtgtgattgatgaacgtttgcatcgtaaccgtgaataccgcgatcgctactaccgtaacttga acattgcacctgccgaggacggctatcgtttagcgggattcccacccgatcatcaggcgtggcgt gaggaaccgtggatccatcacgcccctcaggggtgcgggaacagtagtcgc LTA1 amino acid sequence (SEQ ID NO: 6): MDNGDRLYRADSRPPDEIKRSGGLMPRGHNEYFDRGTQMNI NLYDHARGTQTGFVRYDDGYVSTSLSLRSAHLAGQSILSGYS TYYIYVIATAPNMFNVNDVLGVYSPHPYEQEVSALGGIPYSQI YGWYRVNFGVIDERLHRNREYRDRYYRNLNIAPAEDGYRLA GFPPDHQAWREEPWIHHAPQGCGNSSR PcrV nucleic acid sequence (SEQ ID NO: 7): CATATGGAAGTCAGAAACCTTAATGCCGCTCGCGAGCTGTT CCTGGACGAGCTCCTGGCCGCGTCGGCGGCGCCTGCCAGT GCCGAGCAGGAGGAACTGCTGGCCCTGTTGCGCAGCGAGC GGATCGTGCTGGCCCACGCCGGCCAGCCGCTGAGCGAGGC GCAAGTGCTCAAGGCGCTCGCCTGGTTGCTCGCGGCCAATCAttorney Docket No.3289.0009WO CGTCCGCGCCTCCGGGGCAGGGCCTCGAGGTACTCCGCGA AGTCCTGCAGGCACGTCGGCAGCCCGGTGCGCAGTGGGAT CTGCGTGAGTTCCTGGTGTCGGCCTATTTCAGCCTGCACGG GCGTCTCGACGAGGATGTCATCGGTGTCTACAAGGATGTCC TGCAGACCCAGGACGGCAAGCGCAAGGCGCTGCTCGACGA GCTCAAGGCGCTGACCGCGGAGTTGAAGGTCTACAGCGTG ATCCAGTCGCAGATCAACGCCGCGCTGTCGGCCAGGCAGG GCATCAGGATCGACGCTGGCGGTATCGATCTGGTCGACCCC ACGCTATATGGCTATGCCGTCGGCGATCCCAGGTGGAAGG ACAGCCCCGAGTATGCGCTGCTGAGCAATCTGGATACCTTC AGCGGCAAGCTGTCGATCAAGGATTTTCTCAGCGGCTCGCC GAAGCAGAGCGGGGAACTCAAGGGCCTCAGCGATGAGTAC CCCTTCGAGAAGGACAACAACCCGGTCGGCAATTTCGCCA CCACGGTGAGCGACCGCTCGCGTCCGCTGAACGACAAGGT CAACGAGAAGACCACCCTGCTCAACGACACCAGCTCCCGC TACAACTCGGCGGTCGAGGCGCTCAACCGCTTCATCCAGA AATACGACAGCGTCCTGAGCGACATTCTCAGCGCGATC PcrV amino acid sequence (SEQ ID NO: 8): MEVRNLNAARELFLDELLAASAAPASAEQEELLALLRSERIVL AHAGQPLSEAQVLKALAWLLAANPSAPPGQGLEVLREVLQA RRQPGAQWDLREFLVSAYFSLHGRLDEDVIGVYKDVLQTQD GKRKALLDELKALTAELKVYSVIQSQINAALSARQGIRIDAGG IDLVDPTLYGYAVGDPRWKDSPEYALLSNLDTFSGKLSIKDFL SGSPKQSGELKGLSDEYPFEKDNNPVGNFATTVSDRSRPLND KVNEKTTLLNDTSSRYNSAVEALNRFIQKYDSVLSDILSAI PopB nucleic acid sequence (SEQ ID NO: 9): ATGAACCCGATTACGCTGGAACGTGCTGGTCTGCCGTATGG TGTTGCCGATGCTGGTGACATCCCGGCTCTGGGTCGCCCGG TCGCACGTGATGTGGAAAGTCTGCGTGTTGAACGTCTGGCA GCACCGGCAGCTGCAAGCGCATCTGGCACCGGTGTCGCTCT GACGCCGCCGTCTGCAGCAAGTCAGCAACGTCTGGAAGTTAttorney Docket No.3289.0009WO GCTAACCGCGCGGAAATTGCCTCACTGGTCCAGGCAGTGG GTGAAGACGTGGGTCTGGCACGTCAAGTGGTTCTGGCAGG TGCATCGACCCTGCTGAGCGCAGGTCTGATGTCGCCGCAGG CGTTCGAAATTGAACTGGCCAAAATCACCGGCGAAGTTGA AAATCAGCAGAAAAAACTGAAACTGACGGAAATCGAACA GGCCCGTAAACAGAACCTGCAAAAAATGGAAGATAACCAG CAAAAAATCCGCGAATCGGAAGAAGCTGCGAAAGAAGCG CAGAAAAGCGGCCTGGCCGCAAAAATTTTTGGTTGGATTTC TGCTATCGCGAGTATTATCGTGGGTGCAATCATGGTTGCAA CCGGTGTCGGTGCTGCAGCAGGTGCACTGATGATTGCTGGC GGTGTCATGGGTGTCGTGAGTCAGTCCGTGCAGCAAGCAG CTGCGGATGGTCTGATCTCAAAAGAAGTGATGGAAAAACT GGGCCCGGCCCTGATGGGTATTGAAATGGCCGTGGCACTG CTGGCCGCAGTTGTCTCCTTTGGTGGTTCAGCAGTTGGTGG TCTGGCACGTCTGGGTGCAAAAATCGGCGGTAAAGCTGCG GAAATGACGGCATCCCTGGCTTCAAAAGTGGCAGACCTGG GCGGTAAATTCGGCTCTCTGGCGGGCCAGTCACTGTCGCAT AGCCTGAAACTGGGTGTGCAAGTTTCTGATCTGACCCTGGA CGTTGCAAACGGCGCCGCACAGGCTACGCACAGTGGTTTTC AAGCGAAAGCTGCGAATCGTCAGGCCGATGTTCAAGAATC CCGTGCAGACCTGACCACGCTGCAGGGTGTCATTGAACGTC TGAAAGAAGAACTGAGCCGCATGCTGGAAGCCTTTCAGGA AATTATGGAACGCATCTTCGCAATGCTGCAAGCGAAAGGC GAAACCCTGCACAATCTGTCTTCCCGTCCGGCGGCTATCTG AGGATCC PopB amino acid sequence (SEQ ID NO: 10): MNPITLERAGLPYGVADAGDIPALGRPVARDVESLRVERLAA PAAASASGTGVALTPPSAASQQRLEVANRAEIASLVQAVGED VGLARQVVLAGASTLLSAGLMSPQAFEIELAKITGEVENQQK KLKLTEIEQARKQNLQKMEDNQQKIRESEEAAKEAQKSGLAA KIFGWISAIASIIVGAIMVATGVGAAAGALMIAGGVMGVVSQS VQQAAADGLISKEVMEKLGPALMGIEMAVALLAAVVSFGGSAttorney Docket No.3289.0009WO AVGGLARLGAKIGGKAAEMTASLASKVADLGGKFGSLAGQS LSHSLKLGVQVSDLTLDVANGAAQATHSGFQAKAANRQADV QESRADLTTLQGVIERLKEELSRMLEAFQEIMERIFAMLQAKG ETLHNLSSRPAAI NEAT2 amino acid sequence (SEQ ID NO: 11): KMTDLQDTKYVVYESVENNESMMDTFVKHPIKTGMLNGKK YMVMETTNDDYWKDFMVEGQRVRTISKDAKNNTRTIIFPYV EGKTLYDAIVKVHVKTIDYDGQYHVRIVDKEAFTKAN III.A. Sequence Similarities It is understood that as discussed herein the terms “homology” and “% identity” mean the same thing as “similarity”. Thus, for example, if the use of the word homology is used between two amino acid or nucleic acid sequences it is understood that this is not necessarily indicating an evolutionary relationship between these two sequences, but rather is looking at the similarity or relatedness between their sequences. Many of the methods for determining homology between two evolutionarily related molecules are routinely applied to any two or more nucleic acids or proteins for the purpose of measuring sequence similarity regardless of whether they are evolutionarily related or not. Homology between two nucleic acid sequences can indicate the percentage of nucleotides that are identical between the sequences. Homology between two amino acid sequences indicates the percentage of amino acids that are identical between the sequences. Said percentage is purely statistical, and the differences between the two sequences can be but are not necessarily randomly distributed over the entire length of the sequences to be compared. Comparisons of two sequences are usually carried out by comparing said sequences, after optimal alignment, with respect to a segment or “window of comparison”, in order to identify local regions of corresponding sequences. The optimal alignment for a comparison can be carried out manually or with the aid of the local homology algorithm by Smith and Waterman, 1981, Ads App. Math. 2, 482, with the aid of the local homology algorithm by Needleman and Wunsch, 1970, J. Mol. Biol. 48, 443, with the aid of the similarity search algorithm by Pearson and Lipman, 1988, Proc. Natl Acad. Sci. USA 88, 2444, or with the aid ofAttorney Docket No.3289.0009WO computer programs using said algorithms (GAP, BESTFIT, FASTA, BLAST P, BLAST N and TFASTA in Wisconsin Genetics Software Package, Genetics Computer Group, 575 Science Drive, Madison, Wis.), or by inspection. Homology is obtained by determining the number of identical positions at which the sequences to be compared correspond, dividing this number by the number of positions compared (e.g., the number of positions in the reference sequence) and multiplying this result by 100. In some embodiments, the homology is given for a region which is at least about 50%, at least about 60%, at least about 70%, at least about 80%, at least about 90% or about 100% of the entire length of the reference sequence. For example, if the reference nucleic acid sequence consists of 200 nucleotides, the homology is given for at least about 100, at least about 120, at least about 140, at least about 160, at least about 180, or about 200 nucleotides, in some embodiments in continuous nucleotides. In some embodiments, the homology is given for the entire length of the reference sequence. Nucleic acid sequences or amino acid sequences having a homology to a given nucleic acid sequence or amino acid sequence, respectively, can have at least one functional property of said given sequence, e.g., and in some instances, are functionally equivalent to said given sequence. In some embodiments, a nucleic acid sequence or amino acid sequence having a particular homology to a given nucleic acid sequence or amino acid sequence is functionally equivalent to said given sequence. In general, variants of polypeptides herein disclosed (such as, for example, PcrV, PopB, LTA1, PaF, L-PaF, or NEAT2,) typically have at least about 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, or 99 percent homology to the stated sequence or the native sequence. It is understood that any of the methods typically can be used and that in certain instances the results of these various methods can differ, but the skilled artisan understands if identity is found with at least one of these methods, the sequences would be said to have the stated identity. For example, as used herein, a sequence recited as having a particular percent homology to another sequence refers to sequences that have the recited homology as calculated by any one or more of the calculation methods described above. For instance, a first sequence has 80 percent homology, as defined herein, to a second sequence if the first sequence is calculated to have 80 percent homology to the secondAttorney Docket No.3289.0009WO sequence using the Pearson and Lipman calculation method even if the first sequence does not have 80 percent homology to the second sequence as calculated by the Smith and Waterman calculation method or any of the other calculation methods. As yet another example, a first sequence has 80 percent homology, as defined herein, to a second sequence if the first sequence is calculated to have 80 percent homology to the second sequence using each of calculation methods (although, in practice, the different calculation methods will often result in different calculated homology percentages). III.B. Proteins and Protein Variants As discussed herein there are numerous variants of needle tip protein, translocator protein, the fusion polypeptides thereof, and NEAT2 that are herein contemplated. In addition, to the known functional strain variants there are derivatives of the needle tip protein and translocator protein which also function in the disclosed methods and compositions. Protein variants and derivatives are well understood to those of skill in the art and can involve amino acid sequence modifications. For example, amino acid sequence modifications typically fall into one or more of three classes: substitutional, insertional or deletional variants. Insertions include amino and / or carboxyl terminal fusions as well as intrasequence insertions of single or multiple amino acid residues. Insertions ordinarily will be smaller insertions than those of amino or carboxyl terminal fusions, for example, on the order of one to four residues. Immunogenic fusion protein derivatives, such as those described in the examples, are made by fusing a polypeptide sufficiently large to confer immunogenicity to the target sequence by cross-linking in vitro or by recombinant cell culture transformed with DNA encoding the fusion. Deletions are characterized by the removal of one or more amino acid residues from the protein sequence. In some embodiments, no more than from about 2 to about 6 residues are deleted at any one site within the protein molecule. These variants ordinarily can be prepared by site specific mutagenesis of nucleotides in the DNA encoding the protein, thereby producing DNA encoding the variant, and thereafter expressing the DNA in recombinant cell culture. Techniques for making substitution mutations at predetermined sites in DNA having a known sequence are well known, for example M13 primer mutagenesis and PCR mutagenesis. Amino acid substitutions are typically of single residues but can occur at a number of different locations at once;Attorney Docket No.3289.0009WO insertions usually will be on the order of from about 1 to about 10 amino acid residues; and deletions will range from about 1 to about 30 residues. Deletions or insertions preferably are made in adjacent pairs, i.e. a deletion of 2 residues or insertion of 2 residues. Substitutions, deletions, insertions or any combination thereof can be combined to arrive at a final construct. The mutations should not place the sequence out of reading frame and preferably should not create complementary regions that could produce secondary mRNA structure. Substitutional variants are those in which at least one residue has been removed and a different residue inserted in its place. Such substitutions generally are made in accordance with the following Table 2 and are referred to as conservative substitutions. Table 1, below, lists the amino acid residues and their abbreviations. Table 1. Amino Acids, Three Letter and One Letter Abbreviations. Amino Acid Abbreviations Alanine Ala ATable 2. Exemplary Conservative Amino Acid Substitutions Original Residue Substitution(s)Attorney Docket No.3289.0009WO Gln Asn; Lys Glu Asp Gl Pgical identity can be made by selecting substitutions that are less conservative than those in Table 2, i.e., selecting residues that differ more significantly in their effect on maintaining (a) the structure of the polypeptide backbone in the area of the substitution, for example as a sheet or helical conformation, (b) the charge or hydrophobicity of the molecule at the target site, or (c) the bulk of the side chain. The substitutions which in general are expected to produce the greatest changes in the protein properties will be those in which (a) a hydrophilic residue, e.g. seryl or threonyl, is substituted for (or by) a hydrophobic residue, e.g. leucyl, isoleucyl, phenylalanyl, valyl or alanyl; (b) a cysteine or proline is substituted for (or by) any other residue; (c) a residue having an electropositive side chain, e.g., lysyl, arginyl, or histidyl, is substituted for (or by) an electronegative residue, e.g., glutamyl or aspartyl; (d) a residue having a bulky side chain, e.g., phenylalanine, is substituted for (or by) one not having a side chain, e.g., glycine, in this case, or (e) by increasing the number of sites for sulfation and / or glycosylation. For example, the replacement of one amino acid residue with another that is biologically and / or chemically similar is known to those skilled in the art as a conservative substitution. For example, a conservative substitution would be replacing one hydrophobic residue for another, or one polar residue for another. The substitutions include combinations such as, for example, Gly, Ala; Val, Ile, Leu; Asp, Glu; Asn, Gin; Ser, Thr; Lys, Arg; and Phe, Tyr. Such conservatively substituted variations of each explicitly disclosed sequence are included within the mosaic polypeptides provided herein.Attorney Docket No.3289.0009WO Substitutional or deletional mutagenesis can be employed to insert sites for N- glycosylation (Asn-X-Thr / Ser) or O-glycosylation (Ser or Thr). Deletions of cysteine or other labile residues also can be desirable. Deletions or substitutions of potential proteolysis sites, e.g. Arg, is accomplished for example by deleting one of the basic residues or substituting one by glutaminyl or histidyl residues. Certain post-translational derivatizations are the result of the action of recombinant host cells on the expressed polypeptide. Glutaminyl and asparaginyl residues are frequently post-translationally deamidated to the corresponding glutamyl and asparyl residues. Alternatively, these residues are deamidated under mildly acidic conditions. Other post-translational modifications include hydroxylation of proline and lysine, phosphorylation of hydroxyl groups of seryl or threonyl residues, methylation of the o-amino groups of lysine, arginine, and histidine side chains (T. E. Creighton, Proteins: Structure and Molecular Properties, W. H. Freeman & Co., San Francisco pp 79-86

[1983] ), acetylation of the N-terminal amine and, in some instances, amidation of the C-terminal carboxyl. It is understood that one way to define the variants and derivatives of the disclosed proteins herein is through defining the variants and derivatives in terms of homology / identity to specific known sequences. For example, SEQ ID NO: 2 sets forth a particular sequence of PA needle tip protein-translocator protein fusion (PaF) and SEQ ID NO: 4 sets forth a particular sequence of a LTA1-PaF fusion protein. Specifically disclosed are variants of these and other proteins herein disclosed which have at least, 70% or 75% or 80% or 85% or 90% or 95% homology to the stated sequence. Those of skill in the art readily understand how to determine the homology of two proteins. For example, the homology can be calculated after aligning the two sequences so that the homology is at its highest level. As described above, homology can be performed by published algorithms. Optimal alignment of sequences for comparison can be conducted by the local homology algorithm of Smith and Waterman Adv. App. Math.2: 482 (1981), by the homology alignment algorithm of Needleman and Wunsch, J. MoL Biol.48: 443 (1970), by the search for similarity method of Pearson and Lipman, Proc. Nat. Acad. Sci. U.S.A.85: 2444 (1988), by computerized implementations of these algorithms (GAP, BESTFIT, FASTA, and TFASTA in the Wisconsin Genetics Software Package, Genetics Computer Group, 575 Science Dr., Madison, WI), or by inspection.Attorney Docket No.3289.0009WO The same types of homology can be obtained for nucleic acids by for example the algorithms disclosed in Zuker, M. Science 244:48-52, 1989, Jaeger et al. Proc. Natl. Acad. Sci. USA 86:7706-7710, 1989, Jaeger et al. Methods Enzymol.183:281-306, 1989. It is understood that the description of conservative mutations and homology can be combined together in any combination, such as embodiments that have at least 70% homology to a particular sequence wherein the variants are conservative mutations. As the presently disclosed subject matter provides various proteins and protein sequences it is understood that the nucleic acids that can encode those protein sequences are also disclosed. This would include all degenerate sequences related to a specific protein sequence, i.e. all nucleic acids having a sequence that encodes one particular protein sequence as well as all nucleic acids, including degenerate nucleic acids, encoding the disclosed variants and derivatives of the protein sequences. Thus, while each particular nucleic acid sequence is not necessarily written out herein, it is understood that each and every sequence is in fact disclosed and described herein through the disclosed protein sequences. For example, one of the many nucleic acid sequences that can encode the protein sequence set forth in SEQ ID NO: 2 is set forth in SEQ ID NO: 1. It is understood that for this mutation all of the nucleic acid sequences that encode this particular derivative of the PaF are also disclosed. It is also understood that while no amino acid sequence indicates what particular DNA sequence encodes that protein within an organism, where particular variants of a disclosed protein are disclosed herein, the known nucleic acid sequence that encodes that protein in the particular needle tip protein-translocator protein fusion (such as, for example, PaF) from which that protein arises is also known and herein disclosed and described. It is understood that there are numerous amino acid and peptide analogs which can be incorporated into the disclosed compositions. For example, there are numerous D amino acids or amino acids which have a different functional substituent then the amino acids shown in Table 1 and Table 2. The opposite stereo isomers of naturally occurring peptides are disclosed, as well as the stereo isomers of peptide analogs. These amino acids can readily be incorporated into polypeptide chains by charging tRNA molecules with the amino acid of choice and engineering genetic constructsAttorney Docket No.3289.0009WO that utilize, for example, amber codons, to insert the analog amino acid into a peptide chain in a site-specific way. Molecules can be produced that resemble peptides, but which are not connected via a natural peptide linkage. For example, linkages for amino acids or amino acid analogs can include —CH2NH—, —CH2S—, —CH2—CH2—, — CH═CH-(cis and trans), —COCH2—, —CH(OH)CH2—, and —CHH2SO— (These and others can be found in Spatola, A. F. in Chemistry and Biochemistry of Amino Acids, Peptides, and Proteins, B. Weinstein, eds., Marcel Dekker, New York, p.267 (1983); Spatola, A. F., Vega Data (March 1983), Vol. 1, Issue 3, Peptide Backbone Modifications (general review); Morley, Trends Pharm. Sci (1980) pp. 463-468; Hudson, D. et al., Int J Pept Prot Res 14:177-185 (1979) (—CH2NH—, —CH2CH2— ); Spatola et al. life Sci 38:1243-1249 (1986) (—CH2—S); Hann J. Chem. Soc Perkin Trans. I 307-314(1982) (—CH═CH—, cis and trans); Almquist et al. J. Med. Chem.23:1392-1398 (1980) (—COCH2—); Jennings-White et al. Tetrahedron Lett 23:2533 (1982) (—COCH2—); Szelke et al. European Appln, EP 45665 CA (1982): 97:39405 (1982) (—CH(OH)CH2—); Holladay et al. Tetrahedron. Lett 24:4401-4404 (1983) (—C(OH)CH2—); and Hruby Life Sci 31:189-199 (1982) (— CH2—S—); each of which is incorporated herein by reference. A particularly preferred non-peptide linkage is —CH2NH—. It is understood that peptide analogs can have more than one atom between the bond atoms, such as β-alanine, γ- aminobutyric acid, and the like. Amino acid analogs and analogs and peptide analogs often have enhanced or desirable properties, such as, more economical production, greater chemical stability, enhanced pharmacological properties (half-life, absorption, potency, efficacy, etc.), altered specificity (e.g., a broad-spectrum of biological activities), reduced antigenicity, and others. D-amino acids can be used to generate more stable peptides, because D amino acids are not recognized by peptidases and such. Systematic substitution of one or more amino acids of a consensus sequence with a D-amino acid of the same type (e.g., D-lysine in place of L-lysine) can be used to generate more stable peptides. Cysteine residues can be used to cyclize or attach two or more peptides together. This can be beneficial to constrain peptides into particular conformations.Attorney Docket No.3289.0009WO In some embodiments, the polypeptides administered according to the methods described herein can include antigenic fragments of one or more of subunit (e.g. PcrV, PopB, or NEAT2). Fragments of the sequences of PcrV, PopB, or NEAT2 can be assessed, for example, by determining the ability of the fragments to bind to antibodies that have specific binding to PcrV, PopB, NEAT2, PA or SA and / or to elicit antibodies that cross react with full length PcrV, PopB, PA, NEAT2 or SA. In some embodiments, the antigenic fragment should retain at least about 50%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, or at least about 95% of the antibody binding activity of parent polypeptide. III.C. Nucleic Acids Methods of delivering nucleic acids (such as those that encode the polypeptides of the presently disclosed bivalent vaccine) to cells to express the polypeptides, as well as related vectors and expression systems, are known in art and further described in PCT International Publication Number WO 2022 / 246327, the disclosure of which is incorporated herein by reference in its entirety. IV. Pharmaceutical Compositions The active ingredients (e.g., the fusion polypeptide L-PaF and the polypeptide comprising NEAT2) of the presently disclosed subject matter can be provided in pharmaceutical compositions comprising additional components, e.g., a pharmaceutically acceptable carrier. By “pharmaceutically acceptable” is meant a material that is not biologically or otherwise undesirable, i.e., the material can be administered to a subject without causing any undesirable biological effects or interacting in a deleterious manner with any of the other components of the pharmaceutical composition in which it is contained. The carrier would naturally be selected to minimize any degradation of the active ingredient(s) (e.g., the vaccine polypeptides) and to minimize any adverse side effects in the subject, as would be well known to one of skill in the art. The compositions can be administered orally, parenterally (e.g., intravenously), by intramuscular injection, by intraperitoneal injection, transdermally, extracorporeally, topically or the like, including intranasally (e.g., via topical intranasal administration or administration by inhalant). As used herein, “topical intranasal administration” or “intranasal administration” can refer to delivery of theAttorney Docket No.3289.0009WO compositions into the nose and nasal passages through one or both of the nares and can comprise delivery by a spraying mechanism or droplet mechanism, or through aerosolization of the active ingredients. Administration of the compositions by inhalant can be through the nose or mouth via delivery by a spraying or droplet mechanism. Delivery can also be directly to any area of the respiratory system (e.g., lungs) via intubation. The exact amount of the compositions required will vary from subject to subject, depending on the species, age, weight and general condition of the subject, the severity of the infection being treated, the particular active ingredient(s) used, its mode of administration and the like. Thus, it is not possible to specify an exact amount for every composition. However, an appropriate amount can be determined by one of ordinary skill in the art using only routine experimentation given the teachings herein. Parenteral administration of the composition, if used, is generally characterized by injection. Injectables can be prepared in conventional forms, either as liquid solutions or suspensions, solid forms suitable for solution of suspension in liquid prior to injection, or as emulsions. A more recently revised approach for parenteral administration involves use of a slow release or sustained release system such that a constant dosage is maintained. See, e.g., U.S. Pat. No.3,610,795, which is incorporated by reference herein. The active ingredients can be in solution, suspension (for example, incorporated into microparticles, liposomes, or cells) or emulsion (e.g., an oil-in-water emulsion). In some embodiments, these be targeted to a particular cell type via antibodies, receptors, or receptor ligands. Suitable pharmaceutical carriers and their formulations are described in Remington: The Science and Practice of Pharmacy (19th ed.) ed. A. R. Gennaro, Mack Publishing Company, Easton, PA 1995. In some embodiments, an appropriate amount of a pharmaceutically acceptable salt is used in the formulation to render the formulation isotonic. Examples of the pharmaceutically acceptable carrier include, but are not limited to, saline, Ringer's solution and dextrose solution. The pH of the solution is preferably from about 5 to about 8, more preferably from about 7 to about 7.6, and most preferably about 7.5. Further carriers include sustained release preparations such as semipermeable matrices of solid hydrophobic polymers containing an active ingredient, which matrices are in the form of shaped articles, e.g.,Attorney Docket No.3289.0009WO films, liposomes or microparticles. It will be apparent to those persons skilled in the art that certain carriers can be more preferable depending upon, for instance, the route of administration and concentration of composition being administered. Pharmaceutical carriers are known to those skilled in the art. These most typically would be standard carriers for administration of drugs to humans, including solutions such as sterile water, saline, and buffered solutions at physiological pH. The compositions can be administered intramuscularly or subcutaneously. Other compounds can be administered according to standard procedures used by those skilled in the art. Pharmaceutical compositions can include carriers, thickeners, diluents, buffers, preservatives, surface active agents and the like in addition to the molecule of choice. Pharmaceutical compositions can also include one or more additional active ingredients such as antimicrobial agents, anti-inflammatory agents, anesthetics, and the like. The pharmaceutical composition can be administered in a number of ways depending on whether local or systemic treatment is desired, and on the area to be treated. Administration can be topically (including ophthalmically, vaginally, rectally, intranasally), orally, by inhalation, or parenterally, for example by intravenous drip, subcutaneous, intraperitoneal or intramuscular injection. The disclosed antibodies can be administered intravenously, intraperitoneally, intramuscularly, subcutaneously, intracavity, or transdermally. Preparations for parenteral administration include sterile aqueous or non- aqueous solutions, suspensions, and emulsions. Examples of non-aqueous solvents are propylene glycol, polyethylene glycol, vegetable oils such as olive oil, and injectable organic esters such as ethyl oleate. Aqueous carriers include water, alcoholic / aqueous solutions, emulsions or suspensions, including saline and buffered media. Parenteral vehicles include sodium chloride solution, Ringer's dextrose, dextrose and sodium chloride, lactated Ringer's, or fixed oils. Intravenous vehicles include fluid and nutrient replenishers, electrolyte replenishers (such as those based on Ringer's dextrose), and the like. Preservatives and other additives can also be present such as, for example, antimicrobials, antioxidants, chelating agents, and inert gases and the like. Formulations for topical administration can include ointments, lotions, creams, gels, drops, suppositories, sprays, liquids and powders. ConventionalAttorney Docket No.3289.0009WO pharmaceutical carriers, aqueous, powder or oily bases, thickeners and the like can be desirable. Compositions for oral administration include powders or granules, suspensions or solutions in water or non-aqueous media, capsules, sachets, or tablets. Thickeners, flavorings, diluents, emulsifiers, dispersing aids or binders can be desirable. Some of the compositions can potentially be administered as a pharmaceutically acceptable acid- or base-addition salt, formed by reaction with inorganic acids such as hydrochloric acid, hydrobromic acid, perchloric acid, nitric acid, thiocyanic acid, sulfuric acid, and phosphoric acid, and organic acids such as formic acid, acetic acid, propionic acid, glycolic acid, lactic acid, pyruvic acid, oxalic acid, malonic acid, succinic acid, maleic acid, and fumaric acid, or by reaction with an inorganic base such as sodium hydroxide, ammonium hydroxide, potassium hydroxide, and organic bases such as mono-, di-, tri-alkyl and aryl amines and substituted ethanolamines. Effective dosages and schedules for administering the compositions can be determined empirically, and making such determinations is within the skill in the art. The dosage ranges for the administration of the compositions are those large enough to produce the desired effect in which the symptoms of the infection are affected. The dosage should not be so large as to cause adverse side effects, such as unwanted cross- reactions, anaphylactic reactions, and the like. Generally, the dosage will vary with the age, condition, sex and extent of the disease in the patient, route of administration, or whether other drugs are included in the regimen, and can be determined by one of skill in the art. The dosage can be adjusted by the individual physician in the event of any counterindications. Dosage can vary, and can be administered in one or more dose administrations daily, weekly, or monthly. Guidance can be found in the literature for appropriate dosages for given classes of pharmaceutical products, e.g.,TLR4 agonists. In a preferred embodiment, the amount of polypeptide (e.g., the total amount of L-PaF and NEAT2) that is administered per dose of vaccine is in the range of from about 0.0001 to about 1000 μg / kg. In some embodiments, the amount is in the range of from about 0.001 to about 1000 μg / kg of body weight of the recipient. In some embodiments, the amount is in the range of from about 0.01 to about 1000 μg / kg of body weight of the recipient. In some embodiments, the amount is in the range of fromAttorney Docket No.3289.0009WO about 0.01 to about 100 μg / kg of body weight of the recipient. Those of skill in the art will recognize that the precise dosage can vary from situation to situation and from patient to patient, depending on e.g. age, gender, overall health, various genetic factors, and other variables known to those of skill in the art. Dosages are typically determined e.g. in the course of animal and / or human clinical trials as conducted by skilled medical personnel, e.g. physicians or veterinarians. EXAMPLES The following EXAMPLES provide illustrative embodiments. In light of the present disclosure and the general level of skill in the art, those of skill will appreciate that the following EXAMPLES are intended to be exemplary only that that numerous changes, modifications, and alterations can be employed without departing from the scope of the presently disclosed subject matter. Without further description, it is believed that one of ordinary skill in the art can, using the preceding description and the following illustrative EXAMPLES, make and utilize the presently disclosed compositions and methods EXAMPLE 1 Cystic Fibrosis (CF) Rat Model As aberrant airway mucus is considered a crucial mediator of infection in CF,54animal models that replicate this phenotype are ideal for investigating airway infections. Unlike mice, rats develop extensive submucosal glands in the trachea, better replicating the anatomy of the human airway.55A CFTR- / - (KO) rat that replicates clinical CF pathology has been previously described.56-58The KO rat model develops airway submucosal gland hypertrophy by 6 months of age, leading to aberrant mucus transport. Additionally, this model expresses spontaneous inflammation, prior to infection, by same age. As such, this model can be used to study chronic infections by S. aureus, P. aeruginosa , or both concurrently. When wild type or CF rats were infected with Pa or Sa, all WT rats had high lung CFU burdens at day 3 that are reduced at day 7. See Figures 1A and 1B. In contrast, the CF rat lung burden increases by day 14 back to the day 3 lung burdens. Thus, while mice are used in some of the studies herein as a proof of concept, the CF rat model will also be used as a surrogate for humans.Attorney Docket No.3289.0009WO EXAMPLE 2 Materials and Methods Bacterial Strains, Media, and Growth Conditions: Methicillin resistant S. aureus (MRSA) strains SA0831 (clinical isolate from a CF patient from Dr. S.E. Birket, University of Alabama-Birmingham), AMT0204 and AMT0559, along with methicillin sensitive S. aureus (MSSA) strains ANT0186, AMT0557 (clinical isolates from Dr. R.K. Ernst, University of Maryland-Baltimore) were grown at 37°C in tryptic soy broth (TSB, Difco Laboratories) or on trypticase soy agar. For animal challenge experiments, SA strain SA0831 was grown at 37°C in TSB to an A6001.2. Bacteria were collected from the liquid cultures by centrifugation, washed once with phosphate buffered saline (PBS), and resuspended in PBS to the desired CFU dose, depending upon which animal model was to be used. To enumerate the CFU, the suspensions were serially diluted and plated on Mannitol Salt Agar (MSA) followed by incubation at 37°C overnight. For PA animal infections, the mucoid P. aeruginosa strain mPA08-31 was streaked onto Pseudomonas isolation agar (PIA) and incubated overnight at 37°C. The following day, 20 ml of LB was inoculated with several isolated colonies of PA and incubated overnight at 37°C with shaking at 180 rpm. A 200 µl aliquot from the overnight culture was inoculated into 20 ml of LB and grown at 37°C with 250 rpm shaking the A600reached ∼0.3. PA were collected by centrifugation, washed once, resuspended in PBS, and diluted to desired CFU dose. Protein Preparation: L-PaF was prepared as previously described.12See also, U.S. Patent No. 11,439,700 and PCT International Patent Application Publication No. WO2022 / 246327, the disclosures of which are incorporated herein by reference in their entireties. Briefly, using Novagen’s pACYCDuet-1 synthetic plasmid vector as the mother plasmid, the complex of LTA1-PaF / Histag-PcrHI was produced from the plasmid pACYC-His-PcrH-LTA1-PaF where the brcHI gene was inserted into the BamHI / HindIII sites providing for expression of His-tag PcrH (as set forth in SEQ ID NO: 12 and encoded by the nucleic acid sequence as set forth in SEQ ID NO 13) and LTA1-PaF (as set forth in SEQ ID NO: 4 and encoded by the nucleic acid sequences as set forth in SEQ ID NO: 3) which was inserted at the NdeI-XhoI site. The PaFAttorney Docket No.3289.0009WO sequence had a 3’ stop codon prior to the XhoI restriction site. The plasmid pACYC- His-PcrH-LTA1-PaF was transformed into Tuner cells. E. coli Tuner cells expressing L-PaF / His-Tag PcrH were grown in TB (terrific broth) media supplemented with chloramphenicol (34 μg / ml) with a fed-batch mode in a 10 L bioreactor (Labfors 5, Infors USA Inc., MD). An overnight starter was expanded to 1 L and approximately 800 mL was transferred to the bioreactor containing 9 L of TB media supplemented with chloramphenicol (34 μg / ml). The culture temperature was maintained at 30°C and protein expression was induced adding IPTG to 1 mM when the culture reached an A600 of about 25. After 3 h, the bacteria were collected and processed for purification. The L-PaF / His-Tag PcrH was captured on an IMAC column followed by Q anion exchange chromatography. Lauryldimethylamine oxide (LDAO) was added to a final concentration of 0.1% to release the HT-PcrH. The protein solution was passed over a final IMAC column with the L-PaF passing through the column. L-PaF was dialyzed into PBS with 0.05% LDAO and stored at −80°C. LPS levels were determined using a spectrophotometer system sold under the tradename ENDOSAFE® NexGen PTS™ (Charles River Laboratories, Wilmington, MA). All proteins had LPS levels <5 Endotoxin units / mg protein. NEAT2 (N2) was produced using a codon optimized gene for IsdB residues 351-458 (from IDT) and cloned in-frame into pET15b to have a His-tag and thrombin cleavage site using Gibson assembly. His-N2 was then expressed in E. coli BL21 (DE3) cells and grown in LB broth at 37°C to an A600=0.8. His-N2 was then expressed for 3 h at 37°C followed by adding IPTG to 1mM. The culture was then centrifuged and the cell pellet resuspended in lysis buffer (50 mM Tris-HCl (pH 8.0), 0.1 M NaCl, 2mM MgCl2, 10 mM imidazole, 1mM PMSF, lysozyme (2mg / ml)), lysed by sonication, and the lysate clarified by centrifugation. His-N2 was initially isolated from the clarified lysate using nickel-NTA chromatography and then purified to homogeneity by passage over a HiLoad 26 / 600 Superdex 200 size exclusion column. LPS levels were determined using a spectrophotometer system sold under the tradename ENDOSAFE® NexGen PTS™ (Charles River Laboratories, Wilmington, MA). All proteins had LPS levels <5 Endotoxin units / mg protein. Preparation of L-PaF / ME / N2 FormulationsAttorney Docket No.3289.0009WO ME contains 10 mM histidine, pH 6, 5% sucrose, 2% squalene, 0.5% PS80, which was prepared as previously described.1Briefly, squalene and polysorbate 80 were mixed to achieve a homogenous oil phase. Using a high-speed mixer, 40 mM Histidine (pH 6) and 20% sucrose were added to the oil phase and mixed, followed by six passes through a microfluidizer to generate 4XME. To make the protein / ME formulations, the protein was added to the ME with a final concentration of 0.67 mg / ml, vortexed and allowed to incubate overnight at 4°C. Mice and Immunizations: Six-to eight-week-old female C57BL / 6 mice (n = 20 / group) (Charles River Laboratories, Wilmington, MA) were used for the mouse studies. Prior to vaccination, the following were prepared in 30 µl volumes: PBS, 20 µg N2, 1 μg L-PaF + 1 µg N2 in ME (L-PaF / ME / N21 µg), 1 μg L-PaF + 10 µg N2 in ME (L-PaF / ME / N210 µg) and 1 μg L-PaF + 20 µg N2 in ME (L-PaF / ME / N220 µg). For immunizations, mice were anesthetized using isoflurane and vaccine formulations administered intranasally (IN) as previously described.1Immunizations were on days 0, 14, and 28. Blood was collected prior to each vaccination and at days 42 and 56 from the retro-orbital sinus using sterile glass capillary tubes under proper anesthesia. For MRSA pre-exposure, mice were anesthetized using isoflurane and MRSA (1x107CFU / 30 µl) was administered IN three times with two-week intervals. After the last pre-exposure mice were observed for 30 days followed by immunization using the same method as for the naïve mice. Rabbits and Immunization: 4-5 month-old female rabbits (n=8 / group), weighing 2.0 to 2.8 kg (Envigo, Indianapolis, IN) were used for rabbit studies. The following vaccine formulations were prepared in 500 µl volumes: PBS, 30 μg L-PaF + 50µg N2 in ME (L-PaF / ME / N2 50 µg), 30 μg L-PaF + 100 µg in ME (L-PaF / ME / N2100µg). For immunizations, rabbits were anesthetized by parenteral administration of ketamine-xylazine (ketamine 30mg / kg, xylazine 3mg / kg body weight). The vaccine formulations were administered IN using MAD atomizers (Teleflex, Morrisville, NC) on days 0, 14, and 28. Blood was collected prior to each vaccination and at days 42 and 56 from the marginal ear vein using a 23-gauge needle and syringe under proper anesthesia. For MRSA pre-exposure, anesthetized rabbits were IN administered 1×107CFU / rabbitAttorney Docket No.3289.0009WO two times with a 4-week interval. After the last pre-exposure, rabbits were observed for 30 days then immunized following the methods used for naïve rabbits. Antigen-Specific ELISA: Antibody titers specific for PcrV, PopB and N2 were determined by ELISA, as described previously.12Briefly, 96-well plates coated with PcrV, PopB or N2 (1 μg / ml in PBS) were blocked overnight with 10% milk (Santa Cruz Biotechnology, Dallas, TX) in PBS. Each well was incubated with serum samples from mice or rabbit for 1 h at 37°C. After washing the plates with PBS-Tween (0.05%), secondary antibody was added and incubated for 1 h at 37°C. IgG and IgA titers were determined using HRP-conjugated goat anti-mouse IgG or goat anti-mouse IgA (Southern Biotech, Birmingham, AL) or goat anti-rabbit IgG or goat anti-rabbit IgA (Thermo Fisher Scientific, Waltham, MA) respectively. IgG subtype titers in immunized mice serum were also determined using HRP conjugated goat anti-mouse IgG1, IgG2a, IgG3 (Southern Biotech, Birmingham, AL). 3,3′,5,5′-Tetramethylbenzidine (TMB) substrate was added, and reaction was stopped with H3PO4. Endpoint titers were calculated and represented as Log10 ELISA units per mL (EU / ml). Opsonophagocytic killing assay: Opsonophagocytic killing assay (OPK) was performed as described with some modifications.26Briefly, mouse neutrophils were isolated from bone marrow by a mouse neutrophil isolation kit sold under the tradename MOJOSORT™ (Biolegend, San Diego, CA). Overnight culture of MRSA was diluted 1:100 in Tryptic Soy Broth (TSB) and grown to A600=0.6. The MRSA was washed, resuspended in PBS, and incubated with complement inactivated L-PaF / ME / N2 or PBS immunized mouse sera at 37 °C for 20 min. MRSA / serum mix was added to 105mouse neutrophils at a multiplicity of infection (MOI) of 1:0.5 in the presence of 10% (vol / vol) baby rabbit complement. Following incubation at 37°C for 1 h with agitation at 250 rpm, samples were plated on MSA for CFU enumeration. For PA OPK, overnight cultures of PA were diluted 1:200 in LB and grown to A600=0.3. PA was washed, resuspended in PBS, and incubated with complement inactivated L-PaF / ME / N2 or PBS immunized mouse sera at 37°C for 30 min. PA / serum mix was added to 105mouse neutrophils a multiplicity of infection (MOI) of 1:0.5 in the presence of 10% (vol / vol) baby rabbit complement. Following incubation at 37°C for 1 h with agitation at 250 rpm, samples were plated on PIA for CFU enumeration.Attorney Docket No.3289.0009WO IL-17A and IFN-γ ELISpot: Immunized mouse lungs were extracted and processed to single cell suspensions according to manufacturer’s specifications (Miltenyi Biotec, Gaithersburg, MD). Lung cells (1 x 106cells / well) were incubated for 24 h at 37°C in the presence of 5 μg / ml PcrV, PopB, N2 or PBS, in plates coated with antibodies against IL-17A and IFN-γ for a colorimetric assay as per manufacturer’s specifications (ImmunoSpot, Cleveland, OH). The IL-17A and IFN-γ secreting cells were quantified using a CTL ImmunoSpot reader. Biological negative controls were maintained as PBS mice group while technical negative controls were cells without any protein treatment. Cytokine Determinations: Lung cells were incubated with 10 μg / ml PcrV, PopB, N2 or PBS for 48 h at 37°C. Supernatants were collected and analyzed with U-PLEX kits for cytokines: IFN-γ, IL-2, IL-6, IL-22, IL-17A, and TNF-α (Meso Scale Discovery, Rockville, MD). Cytokine concentrations were determined using an MSD plate reader with associated analytical software (Meso Scale Discovery, Rockville, MD). Mouse challenge study: For MRSA challenge, MRSA strain SA 0831 was prepared as described above. On day 56, mice (n=10) were anesthetized by isoflurane and IN challenged with 1x109CFU / 30 µl MRSA. Clinical body scores were documented as follows: 1: Bright, alert, reactive, shiny hair coat, no piloerection; 2: Quiet, alert, reactive, early- stage piloerection, mild dehydration; 3: Quiet, not very reactive, mild piloerection, moderate dehydration; 4: Minimally reactive, severe piloerection, dull, dirty hair, hunched posture, respiratory distress. Mice were monitored twice a day for weight loss and health scores for 14 days. Mice were euthanized if their weight loss exceeded 25% of their original weight for more than 72 h. All remaining mice were euthanized on day 14 post-challenge. For PA challenge, PA strain mPA08-31 was prepared as above. On day 56, mice (n=5) were anesthetized by isoflurane and IN challenged with 4x107CFU / 30 µl PA. Mice were monitored twice a day for weight loss and health scores for two days. Clinical body scores have been documented as previously described. On day 2 post- infection, mice from each group were euthanized, the lungs were processed, and CFU / lung enumerated on PIA plates.Attorney Docket No.3289.0009WO Rabbit Challenge Study: Both MRSA and PA were grown following the previously described protocol.28,29On day 56, to establish MRSA or PA mediated pneumonia in the rabbit model, a 1.5-ml PBS containing 1×109 / ml MRSA SA0831 strain30or 1.5-ml PBS containing 9×107 / ml PA mPA08-31 strain31was delivered directly into the lungs of anesthetized New Zealand white outbred rabbits through a 2.5-mm pediatric endotracheal tube as described.29Post challenge, rabbits were monitored every 8 hours for the first 48 hpi (hours post infection) and two times daily thereafter. Body weights were measured daily. Body weight loss was calculated for each individual animal using this formula: [100-[((Initial weight - Final weight) / Initial weight) × 100]]. Clinical body scores have been documented as follows: 1: Bright, alert, reactive 2: Quiet, alert, reactive, mild dehydration; 3: Quiet, not very reactive, moderate dehydration, moderate respiratory distress; 4: Minimally reactive, severe respiratory distress, loss of body temperature, loss of activity. Rabbits reached body score 3 or high were euthanized immediately by intravenous administration of a lethal overdose of pentobarbital and survivors were euthanized at 144 hpi following the same method. Lungs were removed aseptically from all the euthanized rabbits, homogenized and CFU enumerated on MSA plates for MRSA and PIA plates for PA. Histological analysis: Following euthanasia, the left lung was harvested and fixed by gravity instillation through the bronchus with 10% formalin. For each left lung, a single section from the upper left lobe was stained with hematoxylin and eosin (H&E) and analyzed in a semiquantitative manner by a single investigator blinded to the experimental groups. Images were taken using Leica DM5500 microscope. Statistical analysis: GraphPad Prism 9.0.1 was used for graphs and statistical analysis. Survival curves were generated using the Kaplan-Meier method, Log-rank (Mantel-Cox) tests were used for survival tests. Mann-Whitney U test (two tailed) was used for comparison between two groups. Kruskal-Willis test with Dunn’s multiple comparison was used for comparison between three or more groups. P values < 0.05 are considered statistically significant. *P < 0.05; **P < 0.01; ***P < 0.001. P values >0.05 were mentioned otherwise.Attorney Docket No.3289.0009WO EXAMPLE 3 L-PaF / ME / N2 Vaccination Protects Mice from MRSA and PA Infections To assess the protective efficacy of N2 and L-PaF / ME / N2, naïve mice were vaccinated using a standard IN three dose regimen, followed by one month of rest prior to pulmonary challenge with MRSA or PA. Vaccine efficacy was determined by survival after MRSA challenge and lung bacterial colonization following PA challenge. Both vaccine formulations protected most of the naïve mice from death after the MRSA challenge with only L-PaF / ME / N2 immunization protecting the naïve mice from PA colonization. In addition, vaccination with N2 and L-PaF / ME / N2 protected mice pre-exposed to MRSA from a subsequent lethal MRSA challenge. These mice were infected IN three times with a sublethal dose of MRSA and one month after the last pre-exposure dose, they were vaccinated and then challenged with MRSA or PA. MRSA pre-exposed mice vaccinated with only N2 exhibited 60% protection while 80% of the mice vaccinated with L-PaF / ME / N2 were protected (see Figure 2A), which is similar to what was seen for the naïve mice. Meanwhile, only L-PaF / ME / N2 vaccinated mice were protected against PA colonization. See Figure 2B. Beyond protective efficacy, results demonstrated that SA pre-exposure had no significant impact on L-PaF / ME / N2 efficacy against PA infection. EXAMPLE 4 L-PaF / ME / N2 Formulations Induce Serum Opsonophagocytic Killing (OPK) Activity The initial mouse trial with N2 was performed with 20 µg N2. A dose escalation trial was then performed with N2 to define an optimal dose. Mice were vaccinated with 1, 10, 20 µg N2 in L-PaF / ME three times biweekly. Serum antibody titers were measured on day 0-, 28-, 42- and 56-days post first vaccination. All the formulations induced significant levels of serum IgG against each of the protein components present in the formulations after three vaccinations. See Figure 3A. The isotype profiling of the antigen specific IgGs induced by vaccination with L- PaF / ME / N2 formulations was examined. A significant increase in antigen specific IgG1 was observed in animals vaccinated with all the formulations except for anti-N2 IgG1 from mice vaccinated with L-PaF / ME / N21 µg. See Figure 3B. An increase was also observed for anti-PcrV IgG2a and IgG3. Statistical differences were not detectedAttorney Docket No.3289.0009WO for anti-PopB and anti-N2 IgG2a or IgG3. The IgA titers were also examined. Significant differences between immunized and control groups were seen only against PcrV antigen. See Figure 3C. When mice were pre-exposed to MRSA, a similar pattern was seen. When mice were subjected to MRSA pre-exposure and then vaccinated, all protein formulations induce significantly elevated level of IgG by day 56, except the anti-N2 titers of L-PaF / ME / N21 µg. See Figure 3D. The IgG isotype profile also showed that vaccination induced a significantly elevated level of IgG1 by day 56. See Figure 3E. When compared to the control group, vaccination with L- PaF / ME / N2, regardless of N2 protein concentration, also induce significant levels of anti-PcrV IgG2a, IgG3, and IgA (see Figure 3F), but no significant difference in levels of anti-PopB and N2 IgG2a, IgG3, and IgA (see Figure 3F) were seen. Based on all the ELISA data, it appears that 10 or 20 µg N2 combined with the L-PaF / ME platform induces a better immune response than L-PaF / ME / N21 µg in both naïve and MRSA pre-exposed mice. The ability of L-PaF / ME / N2 mouse antisera to promote opsonophagocytosis of MRSA and PA by mouse neutrophils was then analyzed. Sera from naïve animals immunized with L-PaF / ME / N210 µg and L-PaF / ME / N220 µg mediated killing of both MRSA (p= 0.0565 for 20 µg (see Figure 4A) and PA (see Figure 4B) within 1 h of incubation. Sera from PBS-immunized animals did not show any bacterial killing. Similar OPK activity was observed for the sera when MRSA (see Figure 4C) and PA (see Figure 4D) were incubated with MRSA pre-exposed L / PaF / ME / N2 vaccinated mouse serum. To demonstrate the broad heterologous protective capacity without sacrificing additional mice, two different MRSA and two different MSSA (methicillin sensitive SA) clinical isolates were collected and opsonophagocytic killing using L- PaF / ME / N2 immunized serum was performed. Sera from animals immunized with L- PaF / ME / N2 formulations and sera from MRSA pre-exposed L-PaF / ME / N2 immunized animals showed killing of both heterologous MRSA and MSSA clinical isolates. EXAMPLE 5 L-PaF / ME / N2 Vaccination Induces Cell-Mediated Immune Response To explore the cell-mediated immune response elicited by L-PaF / ME / N2 vaccination, lung cells were collected from mice (n=5) four weeks after the lastAttorney Docket No.3289.0009WO booster and stimulated with PcrV, PopB or N2 to measure the frequency of IL-17A and IFN-γ secreting cells by ELISpot assay. Lung cells from mice vaccinated with L- PaF / ME / N2 and subsequently stimulated with PcrV, PopB and N2 protein showed significantly higher frequency of IL-17A and IFN-γ cells compared to the control groups for at least one N2 concentration. See Figure 5A. The negative control group, which was not stimulated with any of the antigenic proteins, had no significant detection of IL-17A or IFN-γ secreting cells. This same scheme was used to explore MRSA pre-exposed immune response post L-PaF / ME / N2 immunization. Lung cells from MRSA pre-exposed mice immunized with L-PaF / ME / N2 exhibited significantly higher frequency of IL-17A secreting cells when stimulated with PcrV, PopB or N2 (see Figure 5B) then PBS immunized mice. Lung cells from MRSA pre-exposed vaccinated mice exhibited significantly higher frequencies of IFN-γ secreting cells in response to PopB and N2, with a modest increase also observed following PcrV stimulation. See Figure 5B. ELISpot data indicate that L-PaF / ME / N2 immunization induces Th1-Th17 biased immune response in both naïve and MRSA pre-exposed mice. In addition to ELISpot, lung cells were also collected and stimulated with PcrV, PopB or N2 and secretion of cytokines was measured. The Th1-Th17 bias was assessed by measuring key Th1 and Th17 cytokines: IL-17A, master regulator IL-2, IL-22 (see Figures 6A and 6B), IFN-γ, pro-inflammatory IL-6 and TNF-α. Notably, all the cytokines were significantly upregulated in lung cells from mice immunized with at least one vaccine formulation regardless of whether they were stimulated with PcrV, PopB or N2. Similar cytokine responses were observed with MRSA pre- exposed L-PaF / ME / N2 formulation immunized mice also. See Figures 6C and 6D. These findings suggest that the L-PaF / ME / N2 vaccine formulation induces both Th1 and Th17 responses in both naïve and MRSA pre-exposed mice, which are critical for effective mucosal immunity and bacterial clearance in the context of pulmonary infections. EXAMPLE 6 L-PaF / ME / N2 Induces Consistent Protective Efficacy Against Both MRSA and PA To assess the protective efficacy of L-PaF / ME / N2 against MRSA and PA, the remaining naïve mice were challenged IN with MRSA or PA. Following both MRSAAttorney Docket No.3289.0009WO and PA challenge body weight and clinical scores were monitored; however, no significant difference was observed between PBS and L-PaF / ME / N2 formulation- immunized groups. The results were shown with survival from MRSA challenged mice and bacterial lung burden assessed with PA challenged mice. Both L- PaF / ME / N21 µg and L-PaF / ME / N210 µg formulations resulted in 100% survival when challenged with MRSA, while the L-PaF / ME / N220 µg group exhibited 90% survival. PBS immunized mice showed only 20% survival post MRSA challenge. See Figure 7A. Additionally, mice immunized with all L-PaF / ME / N2 formulations exhibited lower PA burdens in their lungs after PA challenge as compared to PBS vaccinated mice. See Figure 7B. Again, to assess the impact of MRSA pre-exposure on vaccine efficacy, the remaining MRSA pre-exposed mice were challenged with MRSA or PA. Like naïve mice MRSA pre-exposed mice also doesn’t exhibit any significant difference of body weight and clinical scores between PBS and L- PaF / ME / N2 vaccinated groups. Both L-PaF / ME / N21 µg and L-PaF / ME / N210 µg groups achieved 100% survival against MRSA, while the L-PaF / ME / N220 µg group exhibited 80% survival. See Figure 7C. As with the naïve mice, the PA challenge results indicated that MRSA pre-exposure did not adversely affect the vaccine efficacy conferred by our formulations. All vaccinated mice displayed lower PA bacterial loads in their lungs compared to the control group 48 hours post-challenge. See Figure 7D. EXAMPLE 7 L-PaF / ME / N2 Immunization Protects Rabbits Against Lethal MRSA and PA Challenge in Rabbit Models of Pneumonia To assess the protective efficacy of the L-PaF / ME / N2 formulation using a rabbit model, the rabbits were vaccinated three times at two-week intervals. To evaluate immunogenicity, kinetics of antibody titers elicited by the L-PaF / ME / N2 formulation were measured. See Figure 8A. The vaccine formulation induced antigen-specific IgG titers against PcrV and N2, although the magnitude was substantially lower compared to that observed in mice. Notably, the L-PaF / ME / N2 formulation did not elicit any detectable IgG response against PopB. However, no significant differences were detected overall for PcrV or PopB or N2 specific IgA responses. Four weeks following the final booster, rabbits were challenged withAttorney Docket No.3289.0009WO MRSA and PA strains. The health status of the rabbits was monitored daily over a six- day period using a 1 to 4 health scale. Animals that reached a score of 3 or 4 (in any category) were euthanized, as they had become moribund and were expected to die within 24 h. Conversely, animals maintaining a score below 2 fully recovered within the six-day observation period. All PBS immunized rabbits challenged with MRSA (n=4) were euthanized within 19-30 hours post challenge whereas PBS immunized PA challenged rabbits (n=4) euthanized within 25-29 hours post challenge. Immunization with either formulation (L-PaF / ME with 50 or 100 µg N2) conferred complete protection, with 100% of the immunized rabbits surviving the MRSA challenge (see Figure 8B) and the PA challenge. See Figure 8C. Likewise, both formulations either clear or reduce to below the level of detection the MRSA lung burden (see Figure 8D) and the PA lung burden. See Figure 8E. Body weight of all rabbits was also measured during the observation period. Regardless of infection vaccinated rabbits on average lost ≤7% of their body weight before gaining weigh again on day 2 post challenge. When post-challenge histopathology was considered, there were increased levels of hemorrhage, edema and diffuse polymorphonuclear leukocyte (PMN) infiltration in PBS immunized rabbits challenged with both MRSA and PA strain compared with L-PaF / ME / N2 immunized rabbits. See Figures 8F and 8G. In subsequent experiments, rabbits were pre-exposed to MRSA via the IN route twice, with a four-week interval between exposures. Four weeks later, the rabbits were immunized three times at two-week intervals. To assess the immunogenicity of the pre-exposed rabbits, their antibody titers were measured. See Figure 9A. The vaccine induced antigen-specific IgG antibody titers in pre-exposed rabbits comparable to those observed in naïve vaccinated rabbits. Vaccine induced anti-IgA titer also measured and exhibited a trend with L-PaF / ME / N250 µg eliciting slightly better titers to all three antigens which was significant between vaccinated and control groups. Four-weeks after the last booster immunization, the rabbits were challenged. All PBS immunized rabbits challenged with MRSA (n=4) were euthanized within 19-30 hours post challenge whereas PBS immunized PA challenged rabbits (n=3) euthanized within 25-29 hours post challenge. Both L-PaF / ME / N2 formulations were able to protect 100% of the rabbits from MRSA and PA infections compared to the control group. See Figures 9B and 9C. Post-challenge, the lungAttorney Docket No.3289.0009WO bacterial burden of MRSA and PA was lower in rabbits immunized with the L- PaF / ME / N2 formulations. See Figures 9D and 9E. Post challenge rabbits’ body weight also did not exhibit significant differences between any of the groups. However, there is a trend that the weights of the rabbits vaccinated with the 50 µg formulation show faster recovery from both challenges. As with naïve rabbits, post challenge histopathological analysis showed that there were increased level of hemorrhage, edema, PMN infiltration and PMN in bronchi in PBS immunized rabbits challenged with both MRSA and PA strain. See Figures 9F and 9G, left-hand panels. In contrast rabbits immunized with L-PaF / ME / N2 formulation showed minimal alveolar hemorrhage and PMN infiltration post MRSA (see Figure 9F, middle and right-hand panels) and PA challenge (see Figure 9G, middle and right- hand panels), which shows that the L-PaF / ME / N2 vaccine formulation protects rabbits from lethal necrotic pneumonia and infection related lung damage. EXAMPLE 8 Discussion of Examples 2-7 The rise of multidrug resistant strains of SA and PA combined with limited availability of novel therapeutic agents in the development pipeline and an increasing population at risk of contracting these pathogens indicates a troubling trend for SA and PA infections and their implications for global health. In 2017, the World Health Organization (WHO) published a global priority pathogen list, designating P. aeruginosa as critical (priority 1) and S. aureus—specifically MRSA, vancomycin- resistant S. aureus (VRSA), and vancomycin-intermediate S. aureus (VISA)—as high (priority 2) groups for the research and development of new antibiotics.3This classification underscores the urgent need for innovative therapeutic solutions to combat these significant public health threats. As a result, the development of innovative vaccines and immunotherapeutic strategies aimed at reducing both the incidence and severity of MRSA and PA infections could lead to substantial decreases in morbidity and mortality. Additionally, these approaches are expected to reduce overall antibiotic usage, thereby mitigating the selective pressures that drive the emergence of drug resistance. Nevertheless, currently, there are no licensed prophylactic or therapeutic vaccines specifically targeting SA and PA.6,33Attorney Docket No.3289.0009WO In the presently disclosed studies, a new protein subunit vaccine against MRSA and PA infections was designed by combining two T3SS virulence factors from PA and one virulence factor from SA. PcrV and PopB from were selected from PA and fused with LTA1 of enterotoxigenic E. coli to form L-PaF. L-PaF and the N2 domain of IsdB were formulated with the oil-in-water nanoemulsion ME. ME can enhance the multimeric presentation of antigens, thereby boosting the resulting immune response. Herein, it is demonstrated that naïve or SA pre-exposed mice immunized with L-PaF / ME / N2 protected mice against either an MRSA or PA infection. Similarly, rabbits vaccinated with L-PaF / ME / N2 were protected against acute lethal lung infections regardless of MRSA pre-exposure. The presently disclosed subject matter is believed to be the first to describe a multivalent vaccine to protect against both MRSA and PA infections. SA or PA infections are known to elicit robust humoral immune responses, characterized by elevated IgG titers, primarily of the IgG isotype. Antibodies mediate various immunological functions, including opsonization which facilitates phagocytosis and enhances bacterial clearance. In this study, immunization of mice with L-PaF / ME / N2 formulation resulted in a significant increase in total IgG antibody titers. Upon characterizing the IgG subtypes, IgG1 was found to be predominant. The IgG antibody subtypes exhibit differential binding to various bacterial components, enabling their recognition by Fcγ receptors (FcγR) on distinct immune cell populations, thereby facilitating pathogen clearance.36The present findings demonstrate that mouse neutrophils effectively mediated opsonophagocytic killing of MRSA and PA following incubation with heat-inactivated serum from L-PaF / ME / N2- vaccinated mice. The sustained presence of immunoglobulins, coupled with robust opsonophagocytic activity, suggests that the L-PaF / ME / N2 formulation elicits a relevant host immune response that contributes to bacterial clearance. Along with functional antibodies, the T-cell mediated immune response plays an active role in host defense against infection. A successful host defense against microbial infections depends on coordinated interactions between phagocytes, including PMNs and macrophages, along with soluble immune factors, to eliminate pathogens and restore homeostasis. The nature of the T-helper cell-mediated immune response plays an important role in the persistence of PA and SA in the lungs. An anti- inflammatory environment facilitates bacterial proliferation,37,38whereas a Th1-Attorney Docket No.3289.0009WO skewed immune response is associated with improved prognosis. CD4+ T cells are essential not only for supporting antibody responses but also for secreting cytokines, such as IL-17A, which promote the recruitment and activation of innate immune cells, thereby contributing to host defense.39-41In murine models, systemic Th1 responses have been correlated with protection against bacteremia. The present study demonstrates that immunization with L-PaF / ME / N2 not only enhances opsonophagocytic killing by neutrophils but also induces a robust IL-17A response, accompanied by elevated IL-22 levels, which are critical for lung tissue repair.42,43Additionally, a limited IFN-γ response was observed, potentially due to its limited role in enhancing staphylococcal killing by PMNs. However, IFN-γ has been shown to mediate cell-dependent killing of MRSA in other immune cell types, including mast cells, monocytes, and endothelial cells.40,44Along with tissue repair, IL-22 plays another role in mucosal defense by inducing antimicrobial peptides, which limit PA colonization and support barrier integrity during MRSA infection.45In the present study, IL-22 responses peaked at intermediate antigen doses and declined at higher concentrations, which suggests dose-sensitive regulation of mucosal immunity. Elevated levels of IL-2 expression were also found post-stimulation with different antigens in the vaccine formulation. IL-2 supports the expansion and survival of antigen-specific T cells, including Th1 and Th17 subsets, which is important for bacterial clearance.46IL-6 contributes to early inflammation and promotes Th17 differentiation, useful for neutrophil recruitment and control of extracellular pathogens like PA.47Consistent dose-dependent IL-6 responses in the model suggest strong early immune priming relevant to Gram-positive and Gram-negative pulmonary infections. TNF-α is a central mediator of proinflammatory responses, enhancing macrophage activation and leukocyte recruitment during infection.48,49Peak TNF-α production at moderate antigen doses highlights its role in pathogen clearance, while reduced levels at high doses may reflect immunoregulatory feedback to limit tissue damage. Collectively, these findings suggest that the vaccine effectively primes the host immune system of both naïve and MRSA pre-exposed mice, equipping it to combat both PA and MRSA infections, thereby enhancing protective immunity. Cytokine data indicate that MRSA pre-exposure did not have any significant effect on cellular immune response. In the present study, mice were pre- exposed intranasally, and no significant difference in antigen-specific serum IgGAttorney Docket No.3289.0009WO levels was observed compared to naïve mice. These results suggest that mucosal pre- exposure to MRSA did not generate a systemic antibody response. Due to the absence of a systemic immune response in MRSA pre-exposed mice, their cellular immune responses were comparable to those observed in naïve mice. The protective efficacy study using a lung challenge model in naïve and MRSA pre-exposed mice has significant implications for vaccine development. All L-PaF / ME / N2 vaccine formulations provided better protection than the PBS control. Notably, the L-PaF / ME / N2 1^µg and L-PaF / ME / N2 10^µg doses offered greater protection than the L-PaF / ME / N2 20^µg dose, a consistent trend in MRSA pre- exposed mice. This suggests that lower doses are more effective in this model.50Regarding immunogenicity, the L-PaF / ME / N2 10^µg dose consistently induced higher serum IgG levels than the L-PaF / ME / N21^µg dose in both naïve and MRSA pre-exposed mice. The opsonophagocytic killing assay showed a statistically significant improvement in the L-PaF / ME / N2 10^µg group. Cytokine profiling revealed a similar pattern, with the L-PaF / ME / N2 10^µg dose eliciting stronger responses. These results indicate that the L-PaF / ME / N210^µg dose provided the most balanced and robust immune response, making it the optimal dose for use in mice. To enhance the translational impact of the presently disclosed vaccine, an efficacy study of PA and MRSA in an acute pneumonia model using rabbits as an alternative animal model was conducted. This approach overcomes the limitations of mouse models for studying both PA and MRSA infections, as murine PMNs exhibit resistance to MRSA cytotoxins, such as leukocidins, whereas rabbit and human PMNs demonstrate greater sensitivity, highlighting the closer resemblance of the rabbit model to humans.32,51Additionally, rabbits share similar susceptibilities to lipopolysaccharide (LPS) with humans and are naturally susceptible to PA infections.52,53Immunization with L-PaF / ME / N2 shows protection in both naïve and MRSA pre-exposed rabbits against challenges with PA and MRSA, as compared to the PBS control. These results highlight the efficacy of the vaccine in reducing both PA and MRSA infections in an acute pneumonia rabbit model, suggesting its potential for predicting clinical efficacy. Accordingly, the present study provides an initial understanding of the effects of L-PaF / ME / N2 in both murine and rabbit models, demonstrating its ability to prime the host immune system and enhance protection against both pathogens.Attorney Docket No.3289.0009WO EXAMPLE 9 L-PaF / ME / N2 / BECC438s Protects Rats with Wounds Against Pa and MRSA Infections Four groups of Sprague-Dawley rats (n=6 / group) were vaccinated IN with L- PaF / ME / N2 / BECC438s at days 0, 14, and 28. One group of rats received a vaccine with 5 μg N2 and 0.5 μg BECC438s, one group received a vaccine with 5 μg N2 and 1.0 μg BECC438s, one group received a vaccine with 10 μg N2 and 0.5 μg BECC438s, and one group received a vaccine with 10 μg N2 and 1.0 μg BECC438s. As a control, a fifth group of rats was vaccinated using the same schedule using PBS. On day 56, the rats were subjected to 2 mm bilateral wound introduction using a biopsy punch (~ 1 mm deep), infected with mPa08-31 (1 x 107CFU) or SA0831 (1 x 107CFU), and a protective cover applied. The rats were monitored daily for 14 days for infection severity (measured as dermonecrosis area in square mm). Results for the MRSA infected rats are shown in Figure 10A. Results for the PA infected mice are shown in Figure 10B. Faster wound healing was observed in the vaccinated mice, particularly against PA challenge. Rat body weight was also monitored. See Figures 10C and 10D. REFERENCES The references listed below as well as all references cited in the specification are incorporated herein by reference to the extent that they supplement, explain, provide a background for or teach methodology, techniques and / or compositions employed herein. All cited patents and publications referred to in this application are herein expressly incorporated by reference. 1. Howlader, D. R. et al. 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Rozman, P. & Svajger, U. The tolerogenic role of IFN-gamma. Cytokine Growth Factor Rev 41, 40-53 (2018). 45. Wolk, K. et al. IL-22 increases the innate immunity of tissues. Immunity 21, 241-254 (2004). 46. Malek, T. R. & Castro, I. Interleukin-2 receptor signaling: at the interface between tolerance and immunity. Immunity 33, 153-165 (2010). 47. Zhou, L. et al. IL-6 programs T(H)-17 cell differentiation by promoting sequential engagement of the IL-21 and IL-23 pathways. Nat. Immunol 8, 967-974 (2007). 48. Turner, M. D., Nedjai, B., Hurst, T. & Pennington, D. J. Cytokines and chemokines: At the crossroads of cell signalling and inflammatory disease. Biochimica et Biophysica Acta (BBA) - Molecular Cell Research 1843, 2563-2582 (2014). 49. Bradley, J. TNF-mediated inflammatory disease. The Journal of Pathology 214, 149-160 (2008).Attorney Docket No.3289.0009WO 50. Billeskov, R., Babak, B. & and Berzofsky, J. A. The effect of antigen dose on T cell-targeting vaccine outcome. Human Vaccines & Immunotherapeutics 15, 407- 411 (2019). 51. Strandberg, K. L. et al. Staphylococcal superantigens cause lethal pulmonary disease in rabbits. J Infect Dis 202, 1690-1697 (2010). 52. O'Donoghue, P. N. & Whatley, B. F. Pseudomonas aeruginosa in rabbit fur. Lab Anim 5, 251-255 (1971). 53. Gras, E. et al. Development and validation of a rabbit model of Pseudomonas aeruginosa non-ventilated pneumonia for preclinical drug development. Front Cell Infect Microbiol 13, 1297281 (2023). 54. Staudinger et al., Am. J. Respir. Crit. Care Med.189, 812-824 (2014). 55. Widdicomb et al., J. Anat.198 (Part 2), 207-221 (2001). 56. Birket et al., JCI Insight.3, 10.1172 / jci.insight.97199 (2018). 57. Birket et al., Am. J. Respir. Crit. Care Med.202, 1271-1282 (2020). 58. Green et al., Am. J. Physiol. Lung Cell Mol. Physiol., 10.1152 / ajplung.00082.2021 (2021). It will be understood that various details of the presently disclosed subject matter may be changed without departing from the scope of the presently disclosed subject matter. Furthermore, the foregoing description is for the purpose of illustration only, and not for the purpose of limitation.

Claims

Attorney Docket No.3289.0009WO CLAIMS What is claimed is:

1. A method for preventing and / or substantially reducing a Pseudomonas aeruginosa (PA) infection and / or a Staphylococcus aureus (SA) infection in a subject in need thereof, wherein the method comprises administering to the subject a therapeutically effective amount of a composition comprising a vaccine comprising: (a) a fusion polypeptide wherein the fusion polypeptide comprises i) a fusion of a needle tip protein or an antigenic fragment thereof and / or a translocator protein or an antigenic fragment thereof from a Type III secretion system (T3SS) of PA and ii) an A1 subunit of the labile toxin (LTA1) from enterotoxigenic Escherichia coli; and (b) a polypeptide comprising the NEAr transporter 2 domain (NEAT2) of iron- regulated surface determinant protein B (IsdB), wherein the polypeptide comprising NEAT2 has an amino acid sequence of SEQ ID NO: 11, or a polypeptide having at least 90% homology to SEQ ID NO:

11.

2. The method of claim 1, wherein the fusion of a needle tip protein or an antigenic fragment thereof and / or a translocator protein or the antigenic fragment thereof from the T3SS of PA is a polypeptide having an amino acid sequence of SEQ ID NO: 2 (PaF) or an amino acid sequence having at least 90% homology to the amino acid sequence of SEQ ID NO:

2.

3. The method of claim 1 or claim 2, wherein the LTA1 is 5’ of the fusion of the needle tip protein or an antigenic fragment thereof and / or the translocator protein or an antigenic fragment thereof, optionally wherein the LTA1 has an amino acid sequence of SEQ ID NO: 6 or an amino acid sequence having at least 90% homology to the amino acid sequence of SEQ ID NO:

6.

4. The method of any one of claims 1-3, wherein the fusion polypeptide has an amino acid sequence of SEQ ID NO: 4 (L-PaF) or an amino acid sequence having at least 90% homology to SEQ ID NO:

4.

5. The method of any one of claims 1-4, wherein the composition further comprises a nanoemulsion or microemulsion, optionally wherein the microemulsion comprises squalene.Attorney Docket No.3289.0009WO 6. The method of any one of claims 1-5, wherein the composition further comprises a Toll-like receptor 4 (TLR4) agonist, optionally wherein the TLR4 agonist is a lipid A mimetic, further optionally wherein the TLR4 agonist is Bacterial Enzymatic Combinatorial Chemistry (BECC) candidate 438 (BECC438).

7. The method of any one of claims 1-6, wherein the SA infection comprises a methicillin-resistant SA (MRSA) infection.

8. The method of any one of claims 1-7, wherein the subject is a subject that was exposed to SA, optionally MRSA, prior to the administering to the subject a therapeutically effective amount of the composition.

9. The method of any one of claims 1-8, wherein the administering elicits opsonophagocytic killing (OPK) activity and / or elevated levels of secreted IL-17 from lung cells.

10. The method of any one of claims 1-9, wherein the administering produces a response to PA and / or SA that includes a cell-mediated response to eliminate SA and / or PA.

11. The method of any one of claims 1-10, wherein the subject has cystic fibrosis (CF).

12. The method of any one of claims 1-11, wherein the composition is administered to the subject via a route of administration selected from the group consisting of intravenous, oral and inhalation.

13. The method of any one of claims 1-12, wherein the infection is substantially or entirely prevented in the subject.

14. A vaccine formulation for preventing and / or reducing a Pseudomonas aeruginosa (PA) infection and / or a Staphylococcus aureus (SA) infection in a subject, the vaccine formulation comprising: (a) a fusion polypeptide wherein the fusion polypeptide comprises i) a fusion of a needle tip protein or an antigenic fragment thereof and / or a translocator protein or an antigenic fragment thereof from a Type III secretion system (T3SS) of PA and ii) an A1 subunit of the labile toxin (LTA1) from enterotoxigenic Escherichia coli; and (b) a polypeptide comprising the NEAr transporter 2 domain (NEAT2) of iron- regulated surface determinant protein B (IsdB), wherein the polypeptide comprisingAttorney Docket No.3289.0009WO NEAT2 has an amino acid sequence of SEQ ID NO: 11, or a polypeptide having at least 90% homology to SEQ ID NO:

11.

15. The vaccine formulation of claim 14, wherein the fusion polypeptide has an amino acid sequence of SEQ ID NO: 4 (L-PaF) or an amino acid having at least 90% homology to SEQ ID NO:

4.

16. The vaccine formulation of claim 14 or claim 15, wherein the vaccine formulation further comprises a nanoemulsion or microemulsion, optionally wherein the microemulsion comprises squalene.

17. The vaccine formulation of any one of claims 14-16, wherein the vaccine formulation further comprises a Toll-like receptor 4 (TLR4) agonist, optionally wherein the TLR4 agonist is a lipid A mimetic, further optionally wherein the TLR4 agonist is Bacterial Enzymatic Combinatorial Chemistry (BECC) candidate 438 (BECC438).

18. The vaccine formulation of any one of claims 14-17, wherein the SA infection comprises a methicillin-resistant SA (MRSA) infection.

19. The vaccine formulation of any one of claims 14-18, wherein the vaccine formulation elicits protection against the PA and / or SA infection in a subject with a prior history of exposure to SA.

20. The vaccine formulation of any one of claims 14-19, wherein the vaccine formulation elicits opsonophagocytic killing (OPK) activity and / or elevated levels of secreted IL-17 in lung cells of the subject.

21. The vaccine formulation of any one of claims 14-20, wherein the vaccine formulation is effective in a subject that has cystic fibrosis (CF).

22. The vaccine formulation of any one of claims 14-21, wherein the vaccine formulation is formulated for administration to a subject via a route selected from the group consisting of intravenous, oral and inhalation.

23. The vaccine formulation of any one of claims 14-22, wherein administration of the vaccine formulation to a subject substantially or entirely prevents a PA and / or SA infection in a subject.

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