Influence of host factor genes in AIDS-analyses of HIV-1 resistant genes in India

Chemokine receptors or HIV-1 coreceptors are intimately involved in the very early interaction of the host cell with the virus, which leads to the fusion of viral and host cell membrane. Although many coreceptors have been identified, the two most important are CCR5 and CXCR-4. The former receptor is used by the macrophage-tropic isolates during establishment of infection and CXCR-4 using viruses, which are T-lymphocytotropic in nature, are observed during the late stage of infection. Individuals who have a homozygous 32 base pair deletion corresponding to the second extracellular loop of the 7-transmembrane G-coupled protein receptor in CCR5 gene, have been found to resist HIV-1 infection, strongly suggesting that CCR5 is the principal coreceptor involved in transmission. Since chemokines (α & β) can inhibit infection of HIV-1 under in vitro conditions, mutations in the open reading frame of chemokine genes or their promoter regions have become important to study. These chemokines or chemokine receptors are, therefore, promising therapeutic targets for interfering with HIV-1 infection.