Analysis on the relationship between the serum level of Tim-3 and immune function in treponemia pallidum infection patients

ObjectiveTo analyze the serum level of T-cell immunoglobulin domain and mucin domain-containing molecule 3(Tim-3) in treponemia pallidum infection patients, and explore its correlation with immune function.

MethodsOne hundred and five patients with ponemia pallidum infection included 26 cases of primary syphilis, 27 cases of secondary syphilis, 21 cases of third syphilis and 31 cases of latent syphilis, and 30 healthy subjects were set as the control group.The serum levels of Tim-3, humoral immunity index and T lymphocyte subgroup in all subjects were detected.The serum level of Tim-3 in active syphilis patients were detected after treatment.

ResultsThe serum levels of Tim-3, IgG, IgM and IgA in treponemia pallidum infection groups were higher than those in control group(P < 0.01), and the serum levels of Tim-3 in secondary and third syphilis groups were significantly higher than those in primary and latent syphilis groups(P < 0.05 to P < 0.01).The CD4⁺T cell level and ratio of CD4⁺/CD8⁺ in patients with syphilis were significantly lower than those in control group(P < 0.01), while the CD8⁺T cell level in patients with syphilis was significantly higher than that in control group(P < 0.01).After regular syphilis depravation treatment for active syphilis, the serum levels of Tim-3 and peripheral blood CD8⁺ T cell were significantly lower than those before treatment(P < 0.01), and the peripheral blood CD4⁺ T cell level and CD4⁺/CD8⁺ value were significantly higher than those before treatment(P < 0.01).The results of Pearson correlation analysis showed that the level of Tim-3 was positively correlated with the level of CD8⁺ T cells(r=0.52, P < 0.05), negatively correlated with level of CD4⁺ T cells(r=-0.46, P < 0.05), but not significantly correlated with IgG, IgM and IgA(P>0.05).

ConclusionsThe Tim-3 level increasing, hyperhumoral immune function and imbalance of cellular immune function exist in the patients infected with treponema pallidum.The serum level of Tim-3 is correlated with the CD4⁺ and CD8⁺ T cell levels, which may be involved in the process of cellular immune dysfunction of syphilis and accelerating the course of the disease.