5 results about "Secretory IgA" patented technology

This invention provides a composition, preparation method, and application for preventing Helicobacter pylori infection. The composition comprises a mixture of outer membrane vesicles and a solution of *Ackermania pseudomallei* bacteria; the outer membrane vesicle mixture is composed of outer membrane vesicles of *Salmonella* mutant strain QS0074 and outer membrane vesicles of *Escherichia coli* Nissle 1917 at a weight ratio of 2:1; the weight-to-volume ratio of the outer membrane vesicle mixture to the *Ackermania pseudomallei* bacterial solution is 1 mg:1 mL. The composition obtained by this invention significantly outperformed the control group in challenge tests, demonstrating a highly effective preventive effect against Helicobacter pylori infection. Furthermore, the components of the composition of this invention exhibit significant synergistic effects in inducing secretory IgA levels in mice and inducing resistance to Helicobacter pylori infection, showing promising application prospects.

The invention belongs to the field of biological pharmacy and animal medicine, and particularly relates to a nano antibody of antibacterial hair adhesin protein CfaE as well as a preparation method and application of the nano antibody. The invention provides a nano antibody mVHH-IgA of antibacterial hair adhesin protein CfaE, the nano antibody at least comprises a VHH fragment, the VHH fragment comprises three amino acid fragments of CDR1, CDR2 and CDR3, and the amino acid sequence of the CDR1-3 is shown as SEQ ID NO.1-3 in sequence, or the amino acid sequence of the CDR1-3 is shown as SEQ ID NO.4-6 in sequence, and the nano antibody mVHH-IgA of the antibacterial hair adhesin protein CfaE is prepared from the nano antibody mVHH-IgA of the antibacterial hair adhesin protein CfaE, the nano antibody mVHH-IgA of the antibacterial hair adhesin protein CfaE and the nano antibody mVHH-IgA of the antibacterial hair adhesin protein CfaE. Meanwhile, the VHH fragment is also fused with a secreting type IgA alpha chain constant region. The nano antibody mVHH-IgA provided by the invention has high specificity and stability, the nano antibody mVHH-IgA as a feed additive is mixed with a conventional feed to feed animals, and animal experiments show that the animal bacterial diarrhea can be effectively treated by feeding the feed containing the nano antibody mVHH-IgA provided by the invention.

A process is provided for inhibiting or preventing symptoms of necrotizing enterocolitis in a subject that includes the oral administration to the subject of a human polyclonal secretory IgA formed by the conjugation of human recombinant secretory component and pooled human plasma derived dimeric and polymeric. When administered in a therapeutic quantity, symptoms of necrotizing enterocolitis in the subject are inhibited or precluded.

The invention provides an oral plant-probiotic heterologous multifunctional fusion exosome for targeted regulation and control of intestinal mucosa pIgR-IgA transport axis as well as a preparation method and application of the oral plant-probiotic heterologous multifunctional fusion exosome. The fusion exosome is constructed from a plant-derived exosome (such as a garlic exosome) and a probiotic-derived exosome (such as a bacteroides polymorpha exosome) through an ultrasonic membrane fusion technology. According to the invention, the fusion exosome is orally taken for the first time to specifically enhance the transfer of immune globulin A (IgA) mediated by a polyimmunoglobulin receptor (pIgR), so that the concentration of secreted IgA (SIgA) in an enteric cavity is improved, and the immune homeostasis of intestinal mucosa is fundamentally remodeled. In-vitro and in-vivo experiments prove that the core product GB-EV (garlic-bacteroides polymorpha fusion exosome) disclosed by the invention has excellent oral stability and colon targeting property, and can synergistically exert multiple effects of resisting oxidation, resisting inflammation, repairing intestinal barriers and reconstructing flora ecological balance; in an inflammatory bowel disease (IBD) prevention and treatment model, the exosome shows an excellent effect which is obviously superior to that of a single-source exosome and a control fusion exosome. The invention provides a brand new strategy for non-invasive targeted therapy of IBD.

An adjuvant and a transmucosal vaccine may have a high ability of inducing, through transmucosal administration, secretory IgA in addition to serum IgA and IgG. Such an adjuvant may contain, as an active ingredient, one or more polypeptides selected from (1) a polypeptide having one or two amino acid sequences shown in at least SEQ ID NO: 1, and (2) a polypeptide having 93% or more identity to the amino acid sequence.