The mechanism by which human immunodeficiency virus type 1 (HIV-1) causes CD4+ T cell depletion has until now remained largely unexplained. In July
Using chip technology Corbeil et al. measured the simultaneous mRNA expression at eight distinct time points, of 6800 genes in a CD4+ T cell line during the course of HIV infection. They found that responses to infection included a decrease in overall host cell mRNA synthesis, with the replacement of host cell mRNA by viral mRNA, a suppression of mitochondrial and DNA repair gene transcripts and an increased expression of the pro-apoptotic gene and its p53-induced product Bax with the activation of the apoptotic proteins caspase 2, 3 and 9 (Genome Res ...