Estimation of virological and immunological parameters in subjects from South India infected with human immunodeficiency virus type 1 clade C and correlation of findings with occurrence of neurological disease

Several studies carried out in Western countries have demonstrated that a number of virological and immunological markers such as viral loads, cytokines, β2-microglobulin, neopterin, etc., are elevated in the serum and cerebrospinal fluid (CSF) of human immunodeficiency virus (HIV)-infected individuals with neurological disease. The neurological manifestations of HIV infection noted in Indian patients is different from those reported in Western countries. Moreover, few studies have investigated the role of virological and immunological parameters with respect to the progression of HIV-1 clade C infection in India. In this study, we measured virological (HIV-1 RNA levels) and immunological parameters (CD4 cell count and inflammatory markers) in the plasma and CSF of HIV-1-infected neurologically asymptomatic and symptomatic (with opportunistic infections and/or dementia) subjects. By using clade-specific polymerase chain reaction (PCR), we ascertained that all samples used for the study were infected with HIV-1 clade C. Among the various laboratory parameters evaluated, high viral loads in the CSF, low CD4 counts, and higher levels of interleukin (IL)-1α, IL-6, tumor necrosis factor alpha (TNFα), β2-microglobulin, and neopterin were noted in HIV-infected subjects with neurological disease as compared to asymptomatic subjects. These data suggest that the markers evaluated in plasma and CSF samples correlated with occurrence of neurological disease in symptomatic individuals as compared to asymptomatic HIV infected subjects.