Cytokine Responses in the Blood and Pleural Fluid of Pulmonary Tuberculosis Patients with and without HIV-1 Co-infection

Abstract

Tuberculosis (TB) is an opportunistic infectious disease with more severe forms in HIV-1 infected patients. The aim of the present study is to investigate the role of IFN-γ in the other cytokines belonging to Th1, Th17, Th22, and Th3 groups and CD4+ cell counts in the HIV-1 infection in patients co-infected with Mycobacterium tuberculosis. Clinically diagnosed patients of HIV-1, TB and HIV-1 co-infected with TB (HIV-1+TB) groups were selected to test IFN-γ IL-17, IL-22, TGF-β, and also CD4 counts in the blood for the study. Our results showed that IFN-γ and IL-17 cytokines were higher in HIV-1 and TB patients in serum when compared with healthy normal subjects, but there was an insignificant difference when compared with those in HIV-1+TB with TB patients’ samples. Pleural fluid samples of the HIV-1+TB patients showed significantly higher in IL-22 and IFN-γ cytokines than in TB patients, whereas IL-17 showed insignificant differences. CD4+ cells were counted in the blood of HIV-1, TB, and HIV-1+TB patients, however, the results showed that the counts were significantly lower than in the healthy normal group. There was a significantly lower CD4+ count in HIV-1+TB co-infected patients compared to TB patients, but not with HIV-1 patients. The present study suggests that IFN-γ and IL-17 play a significant role individually in HIV-1 and tuberculosis infected patients and IL-22 in pleural fluid in tuberculosis, which differs from those in HIV1 co-infected tuberculosis patients due to the severely affected immune system.