Study on Mycobacterium tuberculosis-specific cellular immunity in individuals co-infected with Mycobacterium tuberculosis and human immunodeficiency virus / 中华传染病杂志

ABSTRACT

Objective To evaluate Mycobacterium tuberculosis (M. tuberculosis)-specific cellular immunity in individuals with latent or active tuberculosis and human immunodeficiency virus (HIV) coinfection. Methods One hundred HIV-infected individuals in Yunnan Province were enrolled. The enzyme-linked immunospot (ELISPOT) assay using early secreted antigenic target (ESAT)-6 and culture filtrate protein (CFP)-10 was employed to detect M. tuberculosis-specific T cells in the peripheral blood. The absolute number of CD3+ CD4+and CD3+ CD8+ T cells in the peripheral blood from the enrolled subjects were determined by flow cytometry. Data were analyzed using nonparametric Mann-Whitney test. Results The prevalence of latent tuberculosis co-infection in HIV-infected individuals without any clinical evidence of active tuberculosis was 67.6%. The absolute numbers of CD3+ CD4+ (532 × 106/L) and CD3+ CD8+ (473 × 106×/L) T cell in HIV-infected individuals with latent tuberculosis co-infection were similar to those of only HIV-infeeted individuals (406 ×106×/L and 504 × 106/L). While those in HIV-infected individuals with active tuberculosis co-infection were 189 × 106/L and 293 × 106/L, respectively, which were both significantly lower than those in other two groups (U=168. 0,U=163. 0,U= 374. 0,U=147. 0, all P<0. 01). Furthermore, ESAT-6 (31/106 cells) and CFP-10 (82/106 cells) specific spot-forming cells in HIV-infected individuals with active tuberculosis co-infection were significantly less than those in HIV-infected individuals with latent tuberculosis co-infection (92 × 106 cells and 109 × 106 cells, U= 507. 0,U= 529. 5, both P<0. 01). Conclusions The prevalence of latent tuberculosis in HIV-positive individuals without any clinical evidence of active tuberculosis is high in China. Both overall cellular immunity and M. tuberculosis-specific immune response in HIV-positive individuals with active tuberculosis co-infection are severely impaired.