Function And Expression Of CD157 In The Patient With Tuberculosis And Its Mechanism

Objective:To investigate the expression of CD157 in healthy controls, latent tuberculosis infection, patients with pneumonia and tuberculosis patients. Using in vitro model to detect the function of expression of CD157 in tuberculosis and its related mechanism.Methods:1. The expression of CD157 was evaluated by q PCR and ELISA in peripheral blood from different patients. Flow cytometry analysis of source of CD157.2. Pleural effusion of tuberculosis pleurisy and non-tuberculosis pleurisy patients were collected, the levels of CD157 protein in the supernatant was evaluated by ELISA.3. Some of the activity of the patients were followed up, CD157 levels were detected at different time points.4. THP-1 cells and PBMC were infected by H37 Ra, and the expression of CD157 was detected.5. To evaluate the relationship of CD157 and IFN gamma, the expression of CD157 and IFN gamma was detected in pleural effusion from TB patients.THP-1 cells were cultured with pleural effusion from pleural tuberculosis patients and patients with non-tuberculosis, and joined the IFN gamma or neutralize the antibody, then the expression of CD157 was detected.6. THP-1cells were stimulated to macrophages by PMA, cultured with CD157 and TB stimulation. Observation the effect of chemokine secretion and cell migration of macrophages infected by tubercμLosis which were treated by CD157.1.The high expression of CD157 in TB:(1) The level of CD157 m RNA in peripheral blood of tuberculosis patients was significantly higher than latent tuberculosis infection, pneumonia and healthy control(P<0.05); the concentration of CD157 in plasma from tuberculosis patients was significantly higher than those from latent tuberculosis infection, pneumonia and healthy(P<0.05); There is no significant difference between the expression of CD157 in the active tuberculosis patients with positive sputum smear and sputum smear negative.(2) Flow cytometry analysis revealed that, CD157 mainly expressed on monocytes, neutrophils, and almost no CD157 expression on T cells; in HC and TB, there were no significant difference of CD157 positive cells in the proportion of different cell.2. The expression of CD157 was decrease after anti-tuberculosis: The expression of CD157 m RNA was evaluated by q PCR and ELISA in peripheral blood from patients with active tuberculosis at different times after treatment. The results showed,in patients with active tuberculosis,CD157 m RNA expression in peripheral blood and CD157 levels in plasma decreased significantly after treatment, compared with statistical difference between both before treatment(P>0.05).3. CD157 enrichment in the pleural fluid in tuberculous pleurisy: CD157 m RNA and plasma levels of CD157 expression in pleural fluid of patients with tuberculous pleurisy were significantly higher than its level of expression in the peripheral blood.The expression of free CD157 of patients with tuberculous pleurisy is significantly higher than that of patients with non-tuberculous pleurisy(P<0.05), has a certain specificity.4. CD157 induced macrophages which infected with Mycobacterium tuberculosis to secrete CCL2, thus promoting cell migration: THP-1 cells were stimulated by CD157 and Mycobacterium tuberculosis. The expression levels of CCL2 were significantly higher than THP-1 were stimulated olny by CD157 or Mycobacterium tuberculosis(P<0.05). Transwell experiments conducted, the results show, CD157 and Mycobacterium tuberculosis can promote the migration of monocytes.If neutralizing antibodies of CCL2 were added into the cell supernatant, migration rate of monocytes was significantly inhibited. The results indicate that migration of monocytes was Results:regulated by ccl2 which expression levels were stimulated by CD157 and Mycobacterium tuberculosis in macrophages.5. The expression of CD157 is upregulated by IFN- gama:The expression of CD157 m RNA or s CD157 amount is not increased in THP-1 and PBMC cells which infected by H37 Ra.There is no significant difference with the control group(P >0.05).THP-1 cells were stimulated with tuberculous pleurisy or non-tuberculous pleurisy. The expression of CD157 m RNA and s CD157 in tuberculous pleurisy was higher than non-tuberculous pleurisy(P<0.05). Further, the expression of IFN gamma and CD157 in TB is positively correlated. THP-1 cells were incubated with functional IFN gamma or neutralizing antibodies of IFN gamma. The results show that IFN gamma can significantly stimulate increased expression of CD157(P<0.05).Conclusion:1. The high expression of CD157 in TB; the expression of CD157 was reduced with anti-tuberculosis treatment; CD157 enrichment in the pleural fluid.2. CD157 induced macrophages which infected with Mycobacterium tuberculosis to secrete CCL2, thus promoting cell migration.3. The expression of IFN gamma and CD157 in TB is positively correlated in pleural fluid of patients with tuberculous pleurisy. The expression of CD157 can be induced by IFN gamma in macrophages.