Investigation of apoptotic markers among human immunodeficiency virus (HIV-1) infected individuals

Background & objectives: Apoptosis causes a decline in the counts of uninfected bystander CD4+ T cells in HIV infection. The rate of disease progression of HIV infection is considered to be faster in the developing countries. The present study was carried out to investigate certain markers for apoptosis in immunopathogensis of disease in HIV infected south Indian population. Methods: Soluble Fas (sFas) antigen and Fas ligand levels in plasma samples from 39 antiretroviral treatment naive patients was estimated and compared with T cell subsets and HIV-1 viral load. Results: The mean sFas antigen levels among controls and the CDC A, B and C clinical stages were 2.77, 3.08, 3.26 and 3.28 ng/ml respectively, higher though not significantly among HIV-1 infected individuals compared to controls. The mean sFas ligand levels in CDC A, B and C stages were 0.138,0.125 and 0.117 ng/ml respectively were higher (P<0.001) than controls (0.073 ng/ml) and positively correlated with total lymphocyte % (r=0.43, P=0.007). Was antigen levels were negatively correlated with total WBC count (r=-0.34, P=0.04), CD4% (r=-0.4, P=0.01) and CD4:CD8 ratio (r=0.37, P=0.02). There was an increase in plasma levels of Was antigen and Fas ligand over time in asymptomatics. Interpretation & conclusions: The high levels of Was antigen and Fas ligand seen in HIV infected individuals suggest increased activation and apoptosis of T cells, due to constant stimulation of the immune system by inter-current infections of HIV infected individuals in south India.