GEOapplication/xmlftp://ftp.ncbi.nlm.nih.gov/geo/series/GSE9nnn/GSE9927/primaryOK2000000GenomicsHomo sapiensExpression profiling by arrayhttps://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE9927GEOGSE0falseChronic CD4+ T cell Activation & Depletion in HIV-1 Infection: Type I Interferon-Mediated Disruption of T Cell DynamicsThe mechanism of CD4(+) T cell depletion during chronic human immunodeficiency virus type 1 (HIV-1) infection remains unknown. Many studies suggest a significant role for chronic CD4(+) T cell activation. We assumed that the pathogenic process of excessive CD4(+) T cell activation would be reflected in the transcriptional profiles of activated CD4(+) T cells. Here we demonstrate that the transcriptional programs of in vivo activated CD4(+) T cells from untreated HIV(+) individuals are clearly different from those activated CD4(+) T cells from HIV(-) individuals. We observed a dramatic up-regulation of cell cycle-associated and interferon-stimulated transcripts in activated CD4(+) T cells of untreated HIV(+) individuals. Furthermore, we find an enrichment of proliferative and Type I interferon-responsive transcription factor binding sites in the promoters of genes that are differentially expressed in activated CD4(+) T cells of untreated HIV(+) individuals compared to HIV(-) individuals. We confirm these findings by examination of in vivo activated CD4(+) T cells. Taken together, these results suggest that activated CD4(+) T cells from untreated HIV(+) individuals are in a hyper-proliferative state that is modulated by Type I interferons. From these results, we propose a new model for CD4(+) T cell depletion during chronic HIV-1 infection. Keywords: disease state analysis2008/02/19GSE9927GSM251192GSM251194GSM251195GSM251196GSM251197GSM251198GSM251110GSM251210GSM251111GSM251199GSM251101GSM251211GSM251200GSM251114GSM251126GSM251105GSM251129GSM251207GSM251208GSM2512095709927Homo sapiens[18077723]