Research On The Role And Diagnostic Value Of MiRNA-451a And Target Genes In The Pathogenesis Of Tuberculosis

Part ? The Role of miRNA-451a and Its Target genes in the Pathogenesis of Tuberculosis[OBJECTIVE]:This study aims to reveal the regulatory role of miRNA-451a in the pathogenesis of tuberculosis.By analyzing the expression differences of miRNA-451a and its target genes MIF and MMP-9 in patients with secondary pulmonary tuberculosis,hematogenous disseminated pulmonary tuberculosis and healthy people,the role of miRNA-451a in the occurrence and development of tuberculosis was speculated.A cell infection model was established to further verify the regulatory role of miRNA-451a.At the same time,the effects of miRNA-451a on macrophage phagocytosis and bactericidal and bacteriostatic effects were revealed through the analysis of cell infection model.[Methods]:The peripheral venous blood of patients with secondary pulmonary tuberculosis,patients with hematogenous disseminated pulmonary tuberculosis and healthy people were collected.RNA was extracted from all the samples and reverse transcription into cDNA.Then,the relative quantitative analysis of the three groups of samples of miRNA-451a and its target genes MIF and MMP-9 was carried out by fluorescence quantitative PCR,and the differences were compared.In this study,THP-1 cell model was used to design a miRNA-451a analogue for transfection to up-regulate or down-regulate its expression.Subsequently,the standard strain H37Rv was used to carry out the cell infection experiment.Colony forming unit(CFU)was compared between the cells with different expression of miRNA-451a.The effect of miRNA-451a on macrophage phagocytosis of Mycobacterium tuberculosis and bacterial survival was analyzed.The expression level of MIF protein in infected cells was analyzed by Western Blot method.[Results]:The expression levels of miRNA-451a and MMP-9 in secondary pulmonary tuberculosis group were lower than those in hematogenous disseminated pulmonary tuberculosis group and healthy control group,while the expression levels of MIF in secondary pulmonary tuberculosis group and hematogenous disseminated pulmonary tuberculosis group were higher than those in healthy control group,with statistical significance(P<0.001).In the cell model,increased expression of miRNA-451a can decrease the level of MIF gene and the level of MIF protein in cells.In addition,the phagocytosis ability of macrophages with higher expression of miRNA-451a was significantly lower than that of macrophages with lower expression of miRNA-451a,and the survival rate of bacteria in cells was higher than that of negative control(P<0.001).[CONCLUSION]:miRNA-451a can negatively regulate its target gene MIF,weaken the phagocytosis and bacteriostatic activity of macrophages,make Mycobacterium tuberculosis easier to escape the immune response of macrophages,and produce more serious clinical types of tuberculosis.PART ? Differential expression and diagnostic value of MIF,ROR alpha and ROR gamma in pleural effusion between pulmonary tuberculosis and lung cancer[Objective]:To analyze the difference of macrophage migration inhibitory factor(MEF),retinoid acid related orphan receptor alpha(ROR a)and retinoid acid related orphan receptor gamma(ROR alpha)in the hydrothorax of patients with pulmonary tuberculosis(TB)and lung cancer,and to explore their values in the differential diagnosis.[Methods]:80 samples of frozen hydrothorax which had been diagnosed as pulmonary tuberculosis and lung cancer were selected,and the basic information of the subjects was collected.The levels of MIF,RORa and RORy in the hydrothorax were detected by Enzyme-Linked Immunosorbent Assay(ELISA),and the application software SPSS20.0 was used for comparison and analysis.[Results]:The median of MIF level(quartile)[M(Q1?Q3)]in the hydrothorax of the patients with tuberculosis and lung cancer were 5.83(2.41 to 16.43)and 2.79(0.91 to 11.12)ng/L respectively,there were significant difference between the groups(P<0.01);The RORa level[M(QI?Q3)]in the hydrothorax of the patients with tuberculosis and lung cancer were 0.63(0.37 to 1.66)and 0.63(0.57-2),respectively,there was no significant difference between the two groups(P>0.05);the level of RORy in the hydrothorax of the patients with tuberculosis and lung cancer were 3.23(1.82 to 5.26)and 3.44(1.94 to 7.11)ng/L respectively,with no significant difference(P>0.05).[Conclusion]:The level of MIF in the hydrothorax of patients with tuberculosis is higher than the patients with lung cancer.The level of MIF in pleural fluid has diagnostic value for the identification of pulmonary tuberculosis and lung cancer,RORa and RORy need further verification.