Gordonia infected animal model and construction method and application thereof
The construction of animal models through the culture and infection methods of Gordonella is solved, and the problem of lack of Gordonella animal models in China is realized, and the research on its pathogenic mechanism and the evaluation of infection response is achieved, providing a basis for drug or vaccine screening. , effectively prevent and control Gordonella infection.
Patent Information
- Application Number
- CN202411257803.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-09
- Publication Date
- 2024-12-10
AI Technical Summary
There is no study on animal models of Gordonella in China, which has led to difficulties in studying its pathogenic mechanism and lacks effective infection prevention and treatment drugs or vaccine screening methods.
Animal models are constructed by culture of Gordonella strains and tail vein injection or airway infection methods, and effective Gordonella infection animal models are established to evaluate the systemic and local immune response of infection to the body.
An animal model of Gordonella infection is provided, which can effectively evaluate the systemic response of infection to the body and local immune response of respiratory tract, help prevent and control Gordonella infection-related diseases, and provide a basis for drug or vaccine screening.
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Figure CN119096937A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of animal model construction, and in particular to an animal model of Gordonia infection and a construction method and application thereof. Background Art
[0002] Gordonia is a class of aerobic, Gram-positive to variable, slightly acid-fast, non-motile short rod-shaped or spherical bacteria. Like other environmental bacteria, Gordonia is a conditional pathogen with low pathogenicity. In most cases, Gordonia infection is caused by the patient's underlying disease and low immunity, but there are also patients with normal immune function who are infected, including pneumonia, sternal wound infection, bacteremia, osteomyelitis, peritonitis, endocarditis and abscesses, among which pneumonia and bacteremia are most commonly reported. Some Gordonia isolated from clinical sites, such as Gordonia bronchialis, are mainly associated with lung infections.
[0003] Although Gordonia is an environmental pathogen, its significance in human pathogens is becoming increasingly important. Although Gordonia amicalis originates from the environment, it can also cause skin infections in trauma patients, breaking the perception that environmental isolates are not pathogenic. Clinical isolates and environmental isolates have low pathogenicity to humans, so the clinical misdiagnosis rate is high. The low incidence of Gordonia in human diseases has led people to ignore the exploration of the pathogenicity of this bacterium and other conditional pathogens from the environment. Therefore, conditional pathogens, especially Gordonia, have attracted people's attention.
[0004] The construction of animal models can provide valuable information for seeking medical knowledge and alleviating human suffering. Since there is no research on the establishment of an animal model of Gordona in China, it has caused great difficulties in the research on the pathogenic mechanism of Gordona, so the establishment of an animal model of Gordona infection has important research value.
[0005] In view of this, the present invention is proposed. Summary of the invention
[0006] The purpose of the present invention is to provide a method for constructing an animal model of Gordona infection and an infected animal model, thereby providing a basis for studying the pathogenic mechanism of Gordona and screening drugs or vaccines for the prevention and treatment of Gordona infection.
[0007] In order to achieve the above-mentioned purpose of the present invention, the following technical solutions are particularly adopted:
[0008] According to one aspect of the present invention, a method for constructing an animal model of Gordonia infection comprises the following steps:
[0009] (A) Cultivation of Gordonia strains;
[0010] (B) Animals were infected by tail vein injection to construct an infected animal model;
[0011] Alternatively, animals may be infected by airway infection to construct an infected animal model.
[0012] The method for constructing an animal model of Gordona infection provided by the present invention comprises the steps of infecting an animal with a bacterial solution obtained after culturing a Gordona strain by tail vein injection or airway infection to construct an infected animal model. The infected animal model can effectively evaluate the systemic response of Gordona infection to the body and the local immune response of Gordona infection to the respiratory tract, thereby helping to prevent and control diseases related to Gordona infection.
[0013] In a preferred embodiment of the present invention, the animal is selected from any one of BALB / c mice, C57BL / 6J mice, ICR mice, hamsters, gerbils, transgenic mice, and gene-deficient mice;
[0014] As a preferred embodiment, the animal is selected from BALB / c mice. In the process of preparing the Rhodococcus model, Balb / c mice are selected because of their good susceptibility to it, and Gordonia and Rhodococcus have similar clinical manifestations. Therefore, this application uses Balb / c mice as experimental mice for animal model experiments.
[0015] In a preferred embodiment of the present invention, the Gordona is selected from: an environmental Gordona standard strain Gordonia amicalis IFM 10353T, a clinical Gordona standard strain G. bronchialis IFM 0150T, or a clinical Gordona standard strain G. sputi H57297.
[0016] As a preferred embodiment, the strain G. bronchialis IFM 0150 used in this application T and G. sputi H57297 were isolated from sputum of clinical patients in Guiyang Pulmonary Hospital, G. amicalis IFM 10353 T Isolated from soil. G.amicalis IFM 10353 was obtained through research in this application. T Although it comes from the environment, it can also cause skin infection in trauma patients, which breaks people's perception that bacteria isolated from the environment will not cause disease.
[0017] In a preferred embodiment of the present invention, the step (A) comprises: inoculating the Gordonia strain into a BHI medium, culturing at 37° C. for 5 days, resuspending the strain and adjusting the concentration to obtain a Gordonia bacterial solution for infection;
[0018] The concentration of the bacterial solution includes: 1.5×10 11 ~1.5×10 12 CFU / L.
[0019] It should be noted that the above-mentioned BHI medium (BD, USA) includes: 7.7 g / L of bovine brain extract powder, 9.8 g / L of bovine heart extract powder, Peptone 10.0 g / L, glucose 2.0 g / L, sodium chloride 5.0 g / L, disodium phosphate 2.5 g / L, pH 7.4±0.2.
[0020] In a preferred embodiment of the present invention, the method of tail vein injection in step (B) comprises: providing a 1.5×10 12 CFU / L of bacterial solution, then take 0.2mL of bacterial solution and infect the animals through the tail vein of mice, and infect once every 2 days for two times to obtain an infected animal model.
[0021] In a preferred embodiment of the present invention, the method for airway infection in step (B) comprises: providing a 1.5×10 12 CFU / L of bacterial solution, and at the same time, the mice were anesthetized and the oral cavity was exposed, and 0.2mL of bacterial solution was injected through the trachea to infect the animals. The animals were infected once every 2 days, and the infection was repeated twice to obtain an infected animal model.
[0022] According to one aspect of the present invention, a Gordona infection animal model is provided. The Gordona infection animal model is mainly constructed by the above-mentioned method for constructing a Gordona infection animal model.
[0023] The Gordonia infection animal model provided by the present invention is mainly constructed by the above-mentioned Gordonia infection animal model construction method, and the infected animal model can effectively evaluate the systemic response of the body caused by Gordonia infection, as well as the local immune response to respiratory tract infection.
[0024] In a preferred embodiment of the present invention, the Gordonia infection animal model comprises: an infection animal model A obtained by injecting Gordonia into an animal through the tail vein;
[0025] and, animal model B of infection obtained by infecting animals with Gordonia via the airways.
[0026] In the above preferred embodiment, the infected animal model A is used to evaluate the systemic response of Gordonia to the body;
[0027] The infection animal model B is used to evaluate the local immune response of Gordonia to respiratory tract infection.
[0028] As a preferred embodiment, the present application has studied that, when infected via tail vein injection, the strains are mostly colonized in the liver and spleen, and a small part is colonized in the lungs, which is suitable for studying the systemic response of Gordona to the body; in the infected animal model B obtained by infection via airway infection, the strains are concentrated in the lungs, and no Gordona colonization is found in the blood, liver and spleen, which can better explore the mechanism of local immunity of the respiratory tract against conditional pathogens.
[0029] According to one aspect of the present invention, the above-mentioned Gordonia infection animal model is used in drug or vaccine screening.
[0030] The Gordonia infection animal model provided by the present invention can be widely used in the screening process of drugs or vaccines for preventing and treating Gordonia infection.
[0031] Compared with the prior art, the present invention has the following beneficial effects:
[0032] The method for constructing an animal model of Gordona infection provided by the present invention comprises the steps of infecting an animal with a bacterial solution obtained after culturing a Gordona strain by tail vein injection or airway infection to construct an infected animal model. The infected animal model provided by the present invention can effectively evaluate the systemic response of Gordona infection to the body, as well as the local immune response of Gordona infection to the respiratory tract, and is helpful to achieve the purpose of preventing and controlling diseases related to Gordona infection.
[0033] The Gordonia infection animal model provided by the present invention can be widely used in the screening process of drugs or vaccines for preventing and treating Gordonia infection. BRIEF DESCRIPTION OF THE DRAWINGS
[0034] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0035] Figure 1 A comparison chart of infection rates of the infected mouse models of Groups 1 to 14 provided in Example 1 of the present invention;
[0036] Figure 2 A bar chart comparing the bacterial load in the liver, lungs and spleen after infection with different strains via tail vein injection provided in Example 2 of the present invention;
[0037] Figure 3a Figure 2 shows the bacterial load in the liver of each experimental group according to different infection routes;
[0038] Figure 3b Figure 2 shows the lung bacterial load of each experimental group according to different infection routes;
[0039] Figure 3c The spleen bacterial load diagram of each experimental group with different infection routes provided in Example 2 of the present invention;
[0040] Figure 4 The pathological characteristic staining images of the liver and lungs of each group of infected Balb / c mice provided in Example 2 of the present invention;
[0041] Figure 5 This is a graph showing the results of culturing tissue homogenates of the 14th, 10th and 6th experimental mouse models provided in Example 2 of the present invention at 37° C. for 10 days. DETAILED DESCRIPTION
[0042] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0043] Examples 1 to 12 (Construction of infection test model)
[0044] (I) Test preparation:
[0045] 1. Strain sources: Gordonia amicalis IFM 10353T (standard strain of Gordonia, environmental source), G. bronchialis IFM 0150T (standard strain of Gordonia, clinical source), G. sputi H57297 (clinical source). All experimental strains were provided by the Microbiology Teaching and Research Department of Guizhou Medical University. The experimental strains were identified by physiological and biochemical methods.
[0046] 2. Preparation of bacterial solution: revive the primary culture, inoculate on BHI medium after thawing, and culture at 37℃ for 5 days; pick the colonies and resuspend them in sterile PBS, and adjust the concentration of the bacterial solution to the required concentration by spectrophotometry and cell counting plate.
[0047] 2. Experimental animals: 70 Balb / c male mice, 6-8 weeks old, weighing 18-22 g, purchased from the Experimental Animal Center of Guizhou Medical University [SCXK (Beijing) 2019-0008]. They were caged and fed for 1 week, with free access to food and water, and the feeding environment was kept clean.
[0048] (II) Experimental Grouping of Examples 1 to 12:
[0049] 70 SPF grade 6-8 week old male Balb / c mice were randomly divided into 14 groups, 5 mice in each group. Different strains (H57297, IFM 0150T, IFM 10353T), bacterial counts (1.5×10 11 , 1.5×10 12 CFU / L) and infection methods ((airway infection), IV) were combined in pairs to form 12 experimental groups, and 12 infected mouse models of the embodiments were obtained.
[0050] The other two groups were control group 1 (airway infection without strain) and control group 2 (tail vein injection without strain), which were divided into 14 groups in total and recorded as group 1 to group 14. See Table 1 for details.
[0051] Table 1:
[0052]
[0053]
[0054]
[0055] In the above embodiments, the tail vein injection (IV) infection method is to slowly inject 0.2 mL of bacterial suspension into the tail vein of mice, stop bleeding with a cotton swab after injection, and infect once every 2 days, for a total of 2 times; the tail vein injection infection control group 2 mice were injected with an equal volume of sterile PBS.
[0056] The airway infection (IT) method was to use a small animal anesthesia machine to perform isoflurane inhalation anesthesia on mice. After the mice entered the anesthesia period, the mouse mouth was exposed, and a 22G / 0.6mm indwelling needle hose was inserted into the trachea through the throat and 0.2mL of bacterial suspension was injected. The infection was performed once every 2 days, for a total of 2 times; (airway infection) The control group 1 mouse was injected with an equal volume of sterile PBS.
[0057] (III) In the above Table 1, mice in each example (Group 1 to Group 14) did not die after 4 days of infection. The results showed that the infection rate of mice in the high-dose group was higher. Therefore, this application adopts 1.5×10 12 The concentration of CFU / L of bacterial solution was used for subsequent research. For specific infection rates, see Figure 1 .
[0058] Figure 1 This is a comparison chart of the infection rates of the infected mouse models in Groups 1 to 14 provided in this example.
[0059] Example 2 (Evaluation of infection test model)
[0060] (I) Changes in status and weight:
[0061] The mice in the two control groups were in good spirits, had good appetite, were active, and had smooth and shiny hair; the mice in experimental groups 3 to 14 were in gradually worse spirits, became sleepy, had lower activity responsiveness, had messy hair, and had decreased appetite.
[0062] Comparison of the mouse models of tail vein injection and airway infection revealed that Group 9, Example 7 (IT-IFM 0150 T ) compared with the original weight of mice in Group 1, there was a significant difference, see Table 2 for details.
[0063] Table 2:
[0064]
[0065]
[0066] Note: (1) Compared with the original body weight of mice, P < 0.05
[0067] (II) Determination of bacterial load in each organ:
[0068] In each example, mice were infected for 5 days, anesthetized and killed by dislocating the neck, and the liver, lungs, and spleen of the mice were removed under sterile conditions. 1 mL of sterile PBS buffer was added to the organs and homogenized with a tissue grinder. After the tissue was homogenized, it was diluted with sterile PBS buffer at a ratio of (1:1 to 1:1000), and 100 mL of the dilution was inoculated into a BHI agar plate containing cycloheximide (100 mg / mL) and nalidixic acid (20 mg / mL). After culturing at 37°C for 10 days, the number of Gordonia colonies was counted. Colony forming unit (CFU) per gram of organ tissue = log10 (colony number × dilution factor) / organ weight.
[0069] Figure 2 The chart is a bar graph comparing the bacterial loads in the liver, lungs and spleen after infection with different strains via tail vein injection.
[0070] Depend on Figure 2 It can be seen that after mice were infected by tail vein injection (IV), whether infected with clinical strains or environmental strains, the bacterial load of Gordonia in the liver and spleen of mice was higher than that in the lungs, and there was a statistical difference (P<0.01);
[0071] However, after mice were infected via airway infection (IT), Gordonia only colonized the lungs, but not the liver or spleen, regardless of the source of the infection strain.
[0072] Figure 3a The liver bacterial load diagram of each experimental group with different infection routes provided in this example;
[0073] Figure 3bThis example provides a graph of lung bacterial loads in each experimental group by different infection routes;
[0074] Figure 3c This example provides a graph of the bacterial load in the spleen of each experimental group with different infection routes.
[0075] Depend on Figure 3a to Figure 3c It can be seen that after IV infection of Gordona from different sources, the bacterial load of Gordona from clinical sources colonizing in the liver and spleen was higher than that of Gordona from environmental sources, with statistical differences (P<0.001), while there was no difference in the bacterial load of the two strains of Gordona from clinical sources (P>0.05); under the two infection routes, the bacterial load of Gordona from different sources in the lungs after IV infection was from high to low in group 6, group 10, and group 14, and the comparison between groups was statistically significant. However, Gordona from different sources only colonized in the lungs after airway infection (IT). After the same strain was infected by different routes, the lung bacterial load after airway infection (IT) was higher than that after tail vein injection (IV) infection (P<0.01), but IFM10353 T After infection, there was no statistical difference in the lung bacterial load between Group 13 and Group 14. The experimental results of the bacterial load in each organ were basically consistent with the experimental results of each organ index.
[0076] (III) Pathological tissue testing:
[0077] The mice in each experimental group were dissected, and the liver and lung of each experimental group were collected, fixed with 10% paraformaldehyde solution, embedded in paraffin, sectioned, stained with hematoxylin-eosin (HE), and observed under an ordinary optical microscope.
[0078] Figure 4 The staining images of the pathological characteristics of the liver and lungs of each group of infected Balb / c mice provided in this example. Figure 4 A is the staining image of liver tissue of group 6; B is the staining image of lung tissue of group 6; C is the staining image of liver tissue of group 10; D is the staining image of lung tissue of group 10; E is the staining image of liver tissue of group 14; F is the staining image of lung tissue of group 14; G is the staining image of liver tissue of group 2; H is the staining image of lung tissue of group 2; I is the staining image of liver tissue of group 5; J is the staining image of lung tissue of group 5; K is the staining image of liver tissue of group 9; L is the staining image of lung tissue of group 9; M is the staining image of liver tissue of group 13; N is the staining image of liver tissue of group 13; O is the staining image of liver tissue of group 1; P is the staining image of lung tissue of group 1.
[0079] Figure 4In middle A, the red arrow indicates necrotic foci; the blue arrow indicates infiltration of granulocytes and lymphocytes; the green arrow indicates focal infiltration of monocytes; the orange arrow indicates hyperplasia of bronchiolar epithelial cells; the yellow arrow indicates necrotic and shedding of bronchiolar epithelial cells; and the black arrow indicates necrotic cell fragments.
[0080] By the above Figure 4 Pathological examination results showed that after infection via tail vein injection (IV), extensive necrotic foci were observed in the liver tissue of group 6, and a large number of hepatocyte nuclei were condensed, darkly stained, fragmented or dissolved and disappeared. Granulocytes and lymphocytes infiltration were observed around the necrotic foci. In the lung tissue, a large area of alveolar wall was moderately thickened, the alveolar spacing was widened, accompanied by a small amount of granulocyte infiltration, and a large number of monocytes were focally infiltrated.
[0081] In group 10, small necrotic foci were often seen in the liver tissue, with many hepatocyte nuclei condensed, deeply stained, fragmented or dissolved and disappeared. A small amount of granulocytes and lymphocytes infiltrated around the necrotic foci. In the lung tissue, a small area of alveolar wall was moderately thickened, the alveolar spacing was widened, and there was a small amount of granulocyte infiltration. Occasionally, mononuclear cells were focally infiltrated.
[0082] In group 14, only a large number of vacuolar degeneration of hepatocytes were observed in the liver tissue, slight thickening was observed locally in the lung tissue, the alveolar spacing was widened, and macrophage infiltration was occasionally seen in the alveolar cavity.
[0083] The pathological results of mice infected with Gordonia from different sources through the airway infection (IT) route showed that in the lung tissue of group 5, large areas of alveolar consolidation, connective tissue hyperplasia, alveolar collapse due to compression, and disappearance of a large number of alveolar structures were observed; a small amount of necrotic cell debris, a large number of granulocytes and lymphocyte infiltration, and occasional hyperplasia of bronchiolar epithelial cells were observed;
[0084] In group 9, multifocal alveolar consolidation, connective tissue hyperplasia, alveolar collapse, and disappearance of alveolar structure were observed in the lung tissues. Infiltration of a large number of granulocytes and lymphocytes, necrosis and shedding of a small number of bronchiolar epithelial cells, and a small amount of necrotic cell fragments were observed.
[0085] In the 13th group of lung tissue, a small amount of granulocyte infiltration was observed in the alveolar walls, a small amount of lymphocyte infiltration was observed around the blood vessels, and foam cells were occasionally seen around the bronchioles.
[0086] (IV) Identification of isolated strains:
[0087] The liver, lung and spleen homogenates collected in the above step (ii) were spread on BHI agar plates respectively, and cultured at 37°C for 10 days. The colonies on the plates were identified by naked eye and microscopic observation.
[0088] Figure 5 This is a graph showing the results of culturing tissue homogenates of the experimental mouse models of Group 14, Group 10 and Group 6 provided in this example at 37°C for 10 days.
[0089] Figure 5 AC are the results of BHI plate culture of mouse tissue homogenates from groups 14, 10 and 6, respectively; DE are the results of microscopic observation of isolated bacteria from mouse tissue homogenates from groups 14, 10 and 6, respectively.
[0090] From the above results, it was found that the strains isolated from the mouse tissue homogenate of the 14th group were cultured on the BHI culture plate at 37°C for 10 days, and orange round colonies with a smooth and moist surface could be seen growing; under the same conditions, the strains isolated from the mouse tissue homogenate of the 10th group showed light yellow wrinkled dry colonies on the culture plate; the strains isolated from the mouse tissue homogenate of the 6th group showed alternating growth of yellow and white wrinkled dry colonies on the culture plate; all the isolated strains showed Gram-positive short rod-like structures under the Gram staining microscope, and it was identified that the strains isolated from the mouse tissues were all pathogenic bacteria that infected mice.
[0091] In summary, the present application established a BALB / c mouse model infected by three strains from different sources, Gordonia sputi H57297, Gordonia bronchialis IFM 0150T, and Gordonia amicalis IFM 10353T, via airway infection and tail vein injection.
[0092] Among them, when infected via tail vein injection, the strains mostly colonize in the liver and spleen, and a small part colonizes in the lungs, which is suitable for studying the systemic response of Gordonia to the body; when infected via airway infection, the strains concentrate in the lungs, which can better explore the mechanism of local immunity of the respiratory tract against conditional pathogens.
[0093] In addition, the present application has found through research that although the virulence of Gordonaella from clinical sources is higher than that from environmental sources, Gordonaella from environmental sources also have pathogenic potential. This application not only lays the foundation for subsequent research on the pathogenic mechanism of Gordonaella, but also provides clues and methods for the establishment of models of other opportunistic pathogens.
[0094] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.
Claims
1. A method for constructing an animal model of Gordonia infection, characterized in that: The construction method comprises the following steps: (A) Cultivation of Gordonia strains; (B) Animals were infected by tail vein injection to construct an infected animal model; Alternatively, animals may be infected by airway infection to construct an infected animal model.
2. The method for constructing an animal model of Gordonia infection according to claim 1, characterized in that: The animal is selected from any one of BALB / c mice, C57BL / 6J mice, ICR mice, hamsters, gerbils, transgenic mice, and gene-deficient mice; Preferably, the animal is selected from BALB / c mice.
3. The method for constructing an animal model of Gordonia infection according to claim 1, characterized in that: The step (A) comprises: The Gordonia strain was inoculated into BHI medium and cultured at 37°C for 5 days. The strain was resuspended and the concentration was adjusted to obtain a Gordonia bacterial solution for infection. The concentration of the bacterial solution includes: 1.5×10 11 ~1.5×10 12 CFU / L.
4. The method for constructing an animal model of Gordonia infection according to claim 1, characterized in that: The method of tail vein injection in step (B) comprises: The concentration obtained by culturing in step (A) is 1.5×10 12 CFU / L of bacterial solution, then take 0.2mL of bacterial solution and infect the animals through the tail vein of mice, and infect once every 2 days for two times to obtain an infected animal model.
5. The method for constructing an animal model of Gordonia infection according to claim 1, characterized in that: The method of airway infection in step (B) comprises: The concentration obtained by culturing in step (A) is 1.5×10 12 CFU / L of bacterial solution, and at the same time, the mice were anesthetized and the oral cavity was exposed, and 0.2mL of bacterial solution was injected through the trachea to infect the animals. The animals were infected once every 2 days, and the infection was repeated twice to obtain an infected animal model.
6. An animal model of Gordonia infection, characterized in that: The Gordonia infection animal model is mainly constructed by the method for constructing a Gordonia infection animal model according to any one of claims 1 to 5.
7. The Gordonia infection animal model according to claim 6, characterized in that: The Gordonia infection animal model includes: Infection animal model A obtained by infecting animals with Gordonia via tail vein injection; and, animal model B of infection obtained by infecting animals with Gordonia via the airways.
8. The Gordonia infection animal model according to claim 7, characterized in that: The infection animal model A is used to evaluate the systemic response of Gordonia to the body; The infection animal model B is used to evaluate the local immune response of Gordonia to respiratory tract infection.
9. Use of the Gordonia infection animal model according to any one of claims 6 to 8 in drug or vaccine screening.