IRF-5 Promotes Cell Death in CD4 T Cells During Chronic Infection (image) Institut national de la recherche scientifique - INRS Share Print E-Mail Caption The study presented by Professor Simona Stager's team points to a mechanism involving the TLR7 receptor (Toll-like Receptor 7), usually activated in innate immune system cells by pathogen recognition. In the case of chronic inflammation, the cellular residues present after tissue destruction activate TLR7 in Th1 cells. Activation of TLR7 induces expression and activation of IRF-5, which in turn increases expression of DR5 (Death Receptor 5) and caspase 8, two signaling elements leading to cell death. Thus, chronic inflammation induces the death of protective CD4 T cells via the TLR7-IRF-5 cellular pathway. Credit INRS Usage Restrictions With the permission of Cell Reports Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.