Application of HCK agonist in resisting mycobacterium tuberculosis infection

Abstract

The invention belongs to the technical field of biological medicines, and particularly relates to application of a non-receptor protein tyrosine kinase agonist in resisting mycobacterium tuberculosis infection. Tyrosine phosphorylated protein is screened out through a bioinformatics technology to serve as a research target, cell and animal experiments are carried out, and it is found that the target agonist improves host immunity and inhibits growth and propagation of mycobacterium tuberculosis by activating immune cells and enhancing the antibacterial function of macrophages. Compared with the traditional antibiotic treatment depending on multi-drug combination, the agonist provided by the invention reduces the dependence on antibiotics through precise targeting immunoregulation, thereby reducing the generation risk of drug-resistant strains.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of biological medicine, and particularly relates to application of a non-receptor protein tyrosine kinase agonist in anti-Mycobacterium tuberculosis infection. BACKGROUND

[0002] Tuberculosis is a common infectious disease in clinical practice, which has characteristics such as long course of disease and long medication course. It is usually treated by combined use of antibacterial drugs. If the patient has poor immune function and is accompanied by multiple underlying diseases, repeated medication treatment may cause dysbiosis, leading to multi-drug resistant organism (MDRO) infection (Qiliying, Li Xuezheng, Guo Xue, et al. Application of bundle management strategy in tuberculosis infection prevention and control management in tuberculosis hospital. Qilu Nursing Journal, 2021, 27(1): 165-167.). After being infected with Mycobacterium tuberculosis, there is a lack of typical clinical symptoms in the early stage. As the bacteria become clearer, the body's resistance gradually decreases. If the abnormal increase of bacterial-mediated allergic reactions occurs, there will be obvious clinical symptoms, including fever, fatigue, poor appetite, weight loss, respiratory tract changes and other conditions, which seriously affect the physical health and life safety of patients (Zhou Jiaxian, Zhang Weifen, Zhou Guijiao. Application of T cell enzyme-linked immunospot assay in investigation of tuberculosis latent infection (LTBI) in comprehensive hospital nursing staff. Nursing Practice and Research, 2020, 17(4): 145-147; Zhang Lijun, Liu Yan, Song Yan. Influence of hospital-family joint supervision and extended care model on family burden and social support of patients with drug-resistant tuberculosis. Nursing Practice and Research, 2022, 19(5): 631-634.). In 2020, about 9.9 million people worldwide were affected by tuberculosis, and about 1.3 million patients died of tuberculosis. With the continuous emergence of anti-tuberculosis drugs, the prevalence of tuberculosis has been limited to a certain extent. However, there are still many deficiencies in anti-tuberculosis treatment. The standard chemotherapy regimen requires at least 4 to 6 months. The economic pressure of long-term treatment of tuberculosis patients and the adverse reactions of anti-tuberculosis drugs make some patients interrupt the anti-tuberculosis treatment, which accelerates the development of drug-resistant tuberculosis. Drug-resistant tuberculosis is resistant to first-line anti-tuberculosis drugs such as isoniazid (INH) and rifampicin (RMP), and a small number of second-line anti-tuberculosis drugs and fluoroquinolones, which leads to a significant decrease in the cure rate of tuberculosis. At the same time, the side effects of anti-tuberculosis drugs and the increasing multi-drug resistance affect the treatment of tuberculosis patients. Therefore, it is urgent to develop new drugs and intervention programs to control infection. Host-directed therapy targets various molecules or pathways in the host immune system, which may help to fight bacterial infection and improve the cure rate of tuberculosis.

[0003] Tyrosine kinase and tyrosine phosphorylation are closely related to a variety of biological processes, and have become one of the most important drug targets. Tyrosine kinase is an important molecule widely existing in human body, and the tyrosine kinase family is divided into two categories: receptor tyrosine kinase family and non-receptor tyrosine kinase family. The receptor tyrosine kinase family is a kind of cell membrane binding protein, which receives the signal transmitted by ligand. They include epidermal growth factor receptor (EGFR), vascular endothelial growth factor receptor (VEGFR) and mesenchymal epithelial transformation factor (c-MET) and other molecular targets. Non-receptor tyrosine kinase includes Ab1, Src family kinase, focal adhesion kinase, etc. The activation of these kinases further activates their downstream signaling molecules to regulate the growth and differentiation of tumor cells. Under normal circumstances, the activation of these molecules is strictly controlled, but in tumor tissues, the activation of receptor and non-receptor tyrosine kinase is disordered, which causes the change of cell proliferation and cell function. Protein phosphorylation is co-regulated by protein kinase and protein phosphatase, which is a key step in cell communication, cell growth and proliferation, cell cycle regulation, differentiation, malignant tumor change, occurrence and metastasis, nerve conduction, vascular formation, embryonic formation and many genetic and acquired human diseases. Therefore, the research on protein phosphorylation has become a hot spot in life science.

[0004] The SRC family of non-receptor protein tyrosine kinases (SFK) consists of 9 members, which can be divided into two groups according to the expression pattern of individual kinases in adults. Therefore, SRC, YES and FYN are ubiquitously expressed, while the expression of LCK, FGR, BLK, LYN, YRK and HCK is limited to certain types of cells and tissues (Poh AR, O'Donoghue RJ, Ernst M. Hematopoietic cell kinase (HCK) as a therapeutic target in immune and cancer cells [J]. Oncotarget. 2015, 6(18): 15752-15771.). Hemopoietic cell kinase (HCK) is expressed in cells of the bone marrow and B-lymphocyte lineage, and the protein exists in two subtypes. HCK can be involved in macrophage activation, myeloid cell growth factor, pro-inflammatory cytokine secretion, mediation of cell development and intracellular signal transduction, and many other physiological and pathological processes (Kim J, Sinn DH, Choi MS, et a1. Hepatocellular carcinoma with extrahepatic metastasis: Are there still candidates for transarterial chemoembolization as an initial treatment? [J]. PkS One, 2019, 14(3): e0213547.). HCK can participate in the course of acute myeloid leukemia by activating signal pathways such as phosphatidylinositol-3-kinase / protein kinase B, mitogen-activated protein kinase / cell extracellular signal-regulated kinase, etc. The SH2 and SH3 domains of HCK affect the development of chronic myeloid leukemia by interacting with Bcr.Abl (Roseweir AK, Powell AGMT, Horstman SL, et a1. Src family kinases. HCK and FGR, associate with local inflammation and turn up progression in colorectal cancer [J] Cell Sisnal, 2019(56): 15-22.).HCK can promote the occurrence of colorectal cancer through Star6-dependent Th2 cytokine signaling pathway, and the survival rate of patients with high expression is lower (antermans HC, Minderman M, Kuil A, et a1. Identification of the SRC-family tyrosine kinase HCK as a therapeutic target in mantle cell lymphoma [J]. Leukemia, 2021, 35 (3): 881-886.). Moreover, sequence changes, copy number aberrations and high expression of HCK are also found in gastric cancer, which is a potential oncogene (Mei J, Zhou WJ, Zhu XY, et a1. Suppression of autophagy and HCK signaling promotes PTGS2 high FCGR3-NK cell differentiation triggered by ectopic endometrial stromal cells [J]. Autophagy, 2018. 14 (8): 1376-1397.), and the occurrence of other solid malignancies such as breast cancer and pancreatic cancer is also closely related to the overexpression of HCK (Ochieng P, Nath S, Macarulay R, et a1. Phospholipid transfer protein and alpha-1 antitrypsin regulate Hck kinase activity during neutrophil degranulation [J]. Sci Rep, 2018, 8 (1): 15394; Poh AR, O'Donoghue RJ, Ernst M. Hematopoietic cell kinase (HCK) as a therapeutic target in immune and cancer cells [J]. Oncotarget, 2015, 6 (18): 15752-15771.). SUMMARY

[0005] The present application finds that the HCK agonist EPQpYEEIPIYL can improve the clearance efficiency of macrophages to MTB infection and enhance immune response. Based on this, the present application is completed.

[0006] In a first aspect, the present application provides a use of an HCK agonist in the manufacture of a medicament for the treatment of Mycobacterium tuberculosis infection, wherein the agonist is capable of inhibiting Mycobacterium tuberculosis infection, and wherein the agonist is EPQpYEEIPIYL.

[0007] Further, the Mycobacterium tuberculosis includes a standard strain of Mycobacterium tuberculosis, a clinical isolate of Mycobacterium tuberculosis, or Mycobacterium tuberculosis carried by a patient infected with Mycobacterium tuberculosis.

[0008] Further, the medicament can be prepared into various dosage forms, including but not limited to one or more of a tablet, a capsule, an aerosol, a pill, a powder, a solution, a suspension, an emulsion, a granule, a liposome, a transdermal agent, and / or a suppository.

[0009] Still further, the preparation can be one or more of a general preparation, a sustained release preparation, a controlled release preparation, and / or various micro-particle drug delivery systems.

[0010] Further, the medicament can be introduced into the body by injection, penetration, absorption, a physical or chemical mediated method.

[0011] Still further, the injection administration includes subcutaneous injection, intravenous injection, intramuscular injection, and intracavity injection, etc.; the cavity administration includes rectal or vaginal administration; the respiratory tract administration includes nasal cavity administration.

[0012] In a second aspect, the present application provides a pharmaceutical composition for the treatment of Mycobacterium tuberculosis, wherein the pharmaceutical composition contains an HCK agonist EPQpYEEIPIYL.

[0013] Further, the Mycobacterium tuberculosis includes a standard strain of Mycobacterium tuberculosis, a clinical isolate of Mycobacterium tuberculosis, or Mycobacterium tuberculosis carried by a patient infected with Mycobacterium tuberculosis.

[0014] Further, one or more pharmaceutically acceptable carriers can be added to the pharmaceutical composition.

[0015] Still further, the carrier material is selected from one or more of a water-soluble carrier material, a poorly soluble carrier material, and / or an enteric soluble carrier material.

[0016] Further, the pharmaceutical composition can be prepared into various dosage forms, including but not limited to one or more of a tablet, a capsule, an aerosol, a pill, a powder, a solution, a suspension, an emulsion, a granule, a liposome, a transdermal agent, and / or a suppository.

[0017] Still further, the preparation can be one or more of a general preparation, a sustained release preparation, a controlled release preparation, and / or various micro-particle drug delivery systems.

[0018] Further, the pharmaceutical composition can be introduced into the body by injection, penetration, absorption, physical or chemical mediation.

[0019] Still further, the injection administration includes subcutaneous injection, intravenous injection, intramuscular injection and intracavity injection, etc.; the cavity administration includes rectal or vaginal administration; the respiratory tract administration includes nasal cavity administration.

[0020] Advantages

[0021] 1. The tyrosine phosphorylated protein HCK is screened by bioinformatics technology, and cell and animal experiments are carried out by knocking out HCK, overexpressing HCK, back supplementing HCK, HCK inhibitor and HCK agonist EPQpYEEIPIYL, it is found that the agonist can significantly improve the clearance efficiency of macrophages to Mycobacterium tuberculosis (MTB) and enhance immune response.

[0022] 2. Compared with the existing anti-tuberculosis treatment method, the HCK agonist activates immune cells and enhances the antibacterial function of macrophages, so as to improve the host immunity and inhibit the growth and spread of Mycobacterium tuberculosis.

[0023] 3. The present application also has the advantage of reducing the risk of drug resistance. Compared with the traditional antibiotic treatment which depends on the combination of multiple drugs, the HCK agonist reduces the dependence on antibiotics through precise targeting of immune regulation, thereby reducing the risk of producing drug-resistant strains. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 : Effect of MTB infected macrophages on HCK tyrosine phosphorylation level.

[0025] Figure 2 : Western blot verification of HCK gene knockout effect. WT is a wild type Thp1 cell, and KO is a Thp1 cell with HCK gene knocked out.

[0026] Figure 3 : CFU identification of the bacteriostatic effect of HCK gene knockout. WT is a wild type Thp1 cell, and KO is a Thp1 cell with HCK gene knocked out.

[0027] Figure 4 : CFU identification of the bacteriostatic effect of HCK gene overexpression. WT is a wild type Thp1 cell, and HCK is a Thp1 cell with HCK gene overexpressed.

[0028] Figure 5 : Effect of HCK gene overexpression on the regulation of autophagy of MTB infected macrophages. NC is a control group without HCK overexpression, and HCK is a group with HCK gene overexpressed.

[0029] Figure 6: Evaluation of the effect of EPQpYEEIPIYL on HCK autophagy pathway. NC is the control group, EPQ is the agonist group.

[0030] Figure 7 : Evaluation of the effect of EPQpYEEIPIYL on HCK autophagy pathway. NC is the control group, EPQ is the agonist group.

[0031] Figure 8 : Evaluation of the effect of iHCK-37 on HCK autophagy pathway. NC is the control group, iHCK is the inhibitor group.

[0032] Figure 9 : CFU count of right lung tissue of three groups of mice after two weeks of BCG infection by aerosol inhalation. DMSO is the control group, iHCK is the inhibitor group, and EPQ is the agonist group.

[0033] Figure 10 : HE staining to identify the effect of HCK on the clearance of BCG infection in mice. DMSO is the control group, iHCK is the inhibitor group, and EPQ is the agonist group. DETAILED DESCRIPTION

[0034] The specific embodiments of the present application are further described below. It should be noted that the description of these embodiments is intended for purposes of illustration only and is not intended to be limiting. Moreover, the technical features involved in the following described embodiments can be combined with each other as long as there is no conflict.

[0035] The experimental methods in the following examples are all conventional methods unless otherwise specified. The experimental materials used in the following examples are all commercially available unless otherwise specified.

[0036] Example 1: Selection of HCK as a research target

[0037] 1.1 Macrophages

[0038] The Thp1 cell line (human acute monocytic leukemia cell line) was obtained from the Bacterial Immunology Room of Beijing Chest Hospital, Capital Medical University.

[0039] 1.2 Mycobacterium tuberculosis strain

[0040] Mycobacterium tuberculosis standard strain H37Rv (ATCC 27298) was preserved by the Bacterial Immunology Room of Beijing Chest Hospital.

[0041] 1.3 MTB infected macrophage model

[0042] (1) Cell plating: cell plating density = 5 x 10 5, PMA (1:1000) stimulation overnight.

[0043] (2) Preparation of bacterial suspension: Add PBS to the grinding flask, scrape the colonies from the culture medium, and transfer them to the grinding flask, shake, stand, ultrasonic dispersion, adjust the bacterial solution to OD 600 1 (1 x 10 8 / mL).

[0044] (3) Infection: Calculate the amount of bacteria according to MOI = 5, and infect macrophages. At 0h, 15min, 30min, 1h, 2h, 4h, 8h, 14h after infection, use RIPA to lyse the protein and collect the sample.

[0045] 1.4 Western Blot

[0046] After sample extraction and protein quantification, separate by SDS-PAGE electrophoresis, transfer to PVDF membrane, then block, antibody incubation and chemiluminescence detection to analyze protein expression.

[0047] 1.5 Result analysis

[0048] WB verification found that the invasion of MTB into macrophages did not significantly change the expression of HCK protein, while the phosphorylation level of HCK Tyr410 site increased first and then decreased with time Figure 1 ), indicating that macrophages experienced dynamic regulation of immune response during the process of responding to MTB infection, involving activation and inhibition mechanisms of HCK, which may be part of the cellular adaptive immune response.

[0049] Example 2 HCK knockout, complementation and overexpression experiments

[0050] 2.1 Construction of HCK knockout strain

[0051] (1) Knock out HCK gene by CRISPR RNP method (Cas9 and sgRNA form a complex).

[0052] (2) Cell preparation: Cell digestion was performed according to the cell passage process; washed with DPBS solution and counted.

[0053] (3) RNP preparation: Prepare RNP complex at a ratio of 5:1-10:1 (sgRNA: Cas9), and stand.

[0054] (4) Electroporation step: Complete nuclear transfection of RNPs with electroporation instrument.

[0055] (5) Single-cell sorting and expansion were completed with Molecular Device's DispenCell Single-Cell Dispenser. After expansion, the cell strains with clear KO genotype (up to 100% KO editing) and good viability were preserved and frozen.

[0056] 2.2HCK wild type and overexpression lentivirus packaging

[0057] To improve the purity and endotoxin-free lentivirus vector and its auxiliary packaging element vector plasmid, the constructed lentivirus vector and its auxiliary packaging element vector plasmid were co-transfected into HEK-293T cells using HGTransgeneTM Reagent. After 10-12 h of transfection, Enhancing buffer was added, and after 8 h, fresh culture medium was replaced. After 48 h of continuous culture, the cell supernatant rich in lentivirus particles was collected, concentrated to obtain high-titer lentivirus concentrate, and the virus titer was determined and calibrated in HEK-293T cells. Lentivirus particles within a certain titer range can meet the needs of most in vivo and in vitro experiments.

[0058] 2.3 Construction and screening of HCK overexpression and back-up stable strains

[0059] (1) Macrophages were derived from 1.1, and the cell suspension with a density of 4x10 5 / mL was added to each well with complete culture medium.

[0060] (2) After the virus was taken out, it was melted in ice bath, and the virus was diluted to the required concentration with complete culture medium according to the MOI value obtained from the relevant literature or pre-experiment. The original culture medium of the cells was removed, and the virus liquid diluted according to the MOI value was added to the cells for system centrifugal infection.

[0061] (3) After 16-24 hours of infection, the cell state was observed in time. If the state changed significantly, the whole volume of medium was replaced after centrifugation. If the state was normal, the culture medium was supplemented to the full volume, and the fresh culture medium was replaced on the third day.

[0062] (4) After 72 hours of infection, the infection was observed to be successful at about 80% under a fluorescence microscope, and the cells that grew well after successful infection were selected with puromycin, expanded, and frozen.

[0063] 2.4 Infection of HCK knockout, overexpression and wild type Thp1 cells with MTB

[0064] The cells were derived from 1.1, and the standard strain H37Rv of Mycobacterium tuberculosis was derived from 1.2. The macrophage infection model was constructed, and the sample was collected after 24 h, and the processing method was the same as 1.3.

[0065] 2.6MTB colony forming unit (CFU) counting

[0066] (1) Pre-add sterile PBS to each tube, suck the cell lysate into the tube marked 10 -1 , mix well, then suck the tube marked 10 -1 into the tube marked 10 -2 , mix well, then suck the tube marked 10 -2 into the tube marked 10 -3 , mix well, and then dilute 10 times in turn to prepare dilutions of different concentrations.

[0067] (2) Mark 10 -1 , 10 -2 , 10 -3 on the 7H10 solid medium, respectively, take 100 μL of dilutions of different concentrations and add them to the culture dish, and then spread them on the medium.

[0068] (3) After about 2-3 weeks, count using the CFU counter.

[0069] 2.7 Western Blot

[0070] The experimental operation steps are the same as those in 1.4.

[0071] 2.8 Statistical analysis and graph drawing

[0072] All statistical analyses were performed using GraphPad Prism Version 9.0 software. For comparison between two groups of data, Student's t-test was used for statistical analysis, and P<0.05 was defined as statistically significant.

[0073] 2.9 Result analysis

[0074] After successfully constructing the HCK knockout cell line ( Figure 2 ), CFU experiments were performed, and the results showed that after HCK knockout, the number of M. tuberculosis colonies increased significantly ( Figure 3 ). On the contrary, after overexpression of the HCK gene, the number of M. tuberculosis colonies decreased significantly ( Figure 4 ), which indicated that the HCK gene might play an important role in inhibiting the growth of M. tuberculosis. Further exploration of the mechanism of the effect of the HCK gene on the growth of M. tuberculosis found that overexpression of the HCK gene led to an increase in LC3 protein expression ( Figure 5 ), which further indicated that HCK inhibited the growth of M. tuberculosis by regulating autophagy function.

[0075] Example 3: Experiment of HCK inhibitor and agonist

[0076] 3.1 Macrophage

[0077] The macrophage was derived from 1.1.

[0078] 3.2 Mycobacterium tuberculosis strain

[0079] The Mycobacterium tuberculosis standard strain H37Rv was derived from 1.2.

[0080] 3.3 Inhibition of macrophage HCK gene by iHCK-37 or EPQpYEEIPIYL

[0081] (1) 0.1 μM concentration of RPMI1640 medium (containing 10% FBS) containing iHCK-37 (C 30 H 32 N4O2S2) or EPQpYEEIPIYL was added 2 hours before infection;

[0082] (2) The bacterial suspension was prepared, MOI = 5, and the macrophage infection model was constructed, as described in 1.3-1.4;

[0083] (3) The sample was collected after 24 hours, and the processing method was the same as that in 2.3. The sample was used for subsequent CFU, WB, PCR and ELISA experiments.

[0084] 3.4 Mycobacterium tuberculosis colony forming unit (CFU) counting

[0085] The experimental operation steps were the same as those in 2.6

[0086] 3.5 Western Blot immunoblotting

[0087] The experimental operation steps were the same as those in 2.7

[0088] 3.6 Statistical analysis and graph drawing

[0089] The analysis method was the same as that in 2.8

[0090] 3.7 Result analysis

[0091] After confirming that the HCK gene can inhibit the growth of Mycobacterium tuberculosis, the effects of HCK agonist (EPQpYEEIPIYL) and HCK inhibitor (iHCK-37) were further evaluated. The results showed that 10 μM of HCK agonist can significantly inhibit the growth of Mycobacterium tuberculosis, while 0.1 μM of HCK inhibitor can significantly promote the growth of Mycobacterium tuberculosis Figure 6 ). Further experiments showed that HCK agonist (EPQpYEEIPIYL) can promote the expression of LC3 Figure 7 ), i.e. enhance the autophagy function of macrophages, thereby improving their bactericidal capacity; while HCK inhibitor (iHCK-37) can inhibit the expression of LC3 Figure 8 .), reducing the autophagic function of macrophages, thereby weakening their killing effect on Mycobacterium tuberculosis.

[0092] Example 4 Mouse Model Verification

[0093] 4.1 BCG strains

[0094] BCG strain BCG (strain number: ATCC35737) was preserved by the Bacterial Immunology Laboratory of Beijing Chest Hospital.

[0095] 4.2 Preparation of BCG strain lysate

[0096] The frozen BCG was taken out for resuscitation, and an appropriate amount of bacterial liquid was aspirated from it, and then smeared on LowensteinJensen (LJ) medium for culture. -245G was used to lyse the collected bacteria. The supernatant after centrifugation was the BCG whole-cell lysate. The concentration of the supernatant was measured and then stored.

[0097] 4.3 BCG infection in mice by tail vein injection

[0098] (1) Experimental groups

[0099] ①DMSO treatment group, ②iHCK-37 treatment group, ③EPQpYEEIPIYL treatment group, 6 mice in each group.

[0100] (2) Infectious strains

[0101] BCG.

[0102] (3) Infection method

[0103] In a negative pressure animal infection laboratory, mice were infected with BCG by tail vein injection. The specific steps were to collect BCG cells in the logarithmic growth phase and adjust the BCG solution to OD 600 =0.5, about 5×10 7 Each mouse was injected with 200 μL of bacterial solution into the tail vein. After the tail vein injection, the mice were housed in separate cages for subsequent experiments.

[0104] 4.4 Processing of spleen and lung tissues after BCG infection in mice

[0105] (1) Counting CFU in mouse lungs

[0106] Four weeks after the mice were injected with the tail vein, six mice in each of the three groups were killed, and the lung tissues of the mice were separated. The lung tissues were placed in a cell filter, and the tissues were ground and broken. The stock solution was serially diluted to 10 -3 , then take 10 -1 , 10 -2 , 10-3 Diluted liquid was plated, and CFU counting was performed after 4 weeks of culture.

[0107] (2) HE staining of lung tissue of mice

[0108] The lung tissue of mice was fixed with 4% paraformaldehyde / general tissue fixative, paraffin-embedded, sectioned, and then the tissue sections were deparaffinized, hydrated, stained with hematoxylin to stain the cell nucleus and eosin to stain the cytoplasm, dehydrated, transparentized, and mounted to observe the structure and morphology of the tissue cells.

[0109] 4.5 Analysis of results

[0110] In the BCG-infected mouse model, Figure 9 It was shown that the HCK agonist EPQpYEEIPIYL promoted the clearance of MTB in the lungs of mice. The HE staining results Figure 10 ) showed that the inflammatory cell infiltration was reduced in the DMSO and iHCK-37 groups, while the inflammatory cell infiltration was increased in the EPQpYEEIPIYL group. This indicates that the HCK inhibitor iHCK-37 inhibited the inflammatory cell infiltration, hindering the clearance of BCG in mice, while the HCK agonist EPQpYEEIPIYL promoted the inflammatory cell infiltration, which was conducive to the clearance of BCG in mice.

Claims

1. Use of an HCK agonist in the preparation of a drug for resisting Mycobacterium tuberculosis infection, wherein the agonist can inhibit Mycobacterium tuberculosis infection, and the agonist is EPQpYEEIPIYL.

2. The use according to claim 1, wherein the Mycobacterium tuberculosis comprises a standard strain of Mycobacterium tuberculosis, a clinical isolate of Mycobacterium tuberculosis, or Mycobacterium tuberculosis carried by a patient infected with Mycobacterium tuberculosis.

3. The use according to claim 1, wherein the drug can be prepared into various dosage forms, including but not limited to one or more of tablets, capsules, aerosols, pills, powders, solutions, suspensions, emulsions, granules, liposomes, transdermal agents and / or suppositories.

4. The use according to claim 1, wherein the drug can be introduced into the body by injection, infiltration, absorption, physical or chemical mediation.

5. The use according to claim 1, wherein the injection administration includes subcutaneous injection, intravenous injection, intramuscular injection and intracavitary injection; the cavity administration includes rectal or vaginal administration; and the respiratory tract administration includes nasal administration.

6. A pharmaceutical composition for use against Mycobacterium tuberculosis, comprising the HCK agonist EPQpYEEIPIYL.

7. The pharmaceutical composition according to claim 6, further comprising one or more pharmaceutically acceptable carriers.

8. The pharmaceutical composition according to claim 6, which can be prepared into various dosage forms, including but not limited to one or more of tablets, capsules, aerosols, pills, powders, solutions, suspensions, emulsions, granules, liposomes, transdermal agents and / or suppositories.

9. The pharmaceutical composition according to claim 6, wherein the preparation can be one or more of a conventional preparation, a sustained-release preparation, a controlled-release preparation and / or various microparticle delivery systems.

10. The pharmaceutical composition according to claim 6, which can be introduced into the body by injection, permeation, absorption, physical or chemical mediation.

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