Correlation of partial env gene sequences with disease progression parameters in HIV-positive pregnant women from India

Ever since the beginning of the epidemic of HIV, one of the poignant aspects of HIV infection is transmission of the virus from mother to child. It is not known whether pregnancy accelerates the progression of HIV infection from a clinically asymptomatic stage to a progressive clinical phase. Present study was carried out to understand disease progression in pregnant women from India. We studied co-receptor utilization (the major determinant of HIV disease progression), N-glycosylation sites, and sequence variability. Blood samples were collected from 25 HIV sero-positive patients, eleven from the antenatal risk group (experimental group), nine from heterosexual male, and five from heterosexual female risk group (control group). Partial env gene was amplified by PCR and sequenced. BLAST search and phylogenetic analysis were used to determine the subtype. The deduced amino acid sequence of the V3 region was used to predict co-receptor, determine sequence variability and N-glycosylation site. The experimental group comprising the antenatal risk group did not exhibit any difference in terms of co-receptor, N-glycosylation, and sequence variability when compared with the control, non-pregnant group. Pregnancy does not seem to accelerate the clinical course of HIV infection. The female body during the gestation phase possibly acquires certain strategies to impede or at least alleviate the disease progression during the crucial immune-compromised pregnancy phase, which would otherwise adversely affect the mother as well as the fetus during the infection.