MAPK-activated protein kinase 2 orchestrates memory T-cell inflation in cytomegalovirus infection

Le résumé fourni par la source

Memory T-cell inflation is a distinctive immunological phenomenon observed during persistent viral infections such as cytomegalovirus (CMV). Unlike conventional memory T-cell responses, which contract after infection resolution, a subset of CMV-specific T cells undergoes a progressive and sustained expansion, termed "inflation", which is thought to be critical for long-term immune surveillance. The molecular mechanisms that govern memory T-cell inflation remain incompletely understood, yet they are pivotal for understanding immune persistence and designing strategies against chronic viral infections. In this study, we investigated the role of MAPK-activated protein kinase 2 (MK2), a key downstream effector of p38 MAPK signaling, in regulating T-cell responses during murine CMV (MCMV) infection. Using MK2 knockout (MK2-KO) mice, we demonstrate that MK2 deficiency alters the dynamics of MCMV-specific CD8+ T-cell responses without impairing viral control or tissue replication. MK2 deficiency led to a reduction in noninflationary MCMV-specific CD8+ T cells during acute infection, followed by enhanced expansion of inflationary CD8+ T-cell subsets during latent infection. Furthermore, MK2-KO mice exhibited impaired effector differentiation, as evidenced by decreased expression of the terminal differentiation marker KLRG1 on MCMV-specific CD8+ T cells. Collectively, these findings identify MK2 as an important regulator of CD8+ T-cell magnitude, kinetics, and phenotype during both acute and latent MCMV infection. By demonstrating a role of MK2 in the regulation of memory T-cell inflation, this study provides new mechanistic insight into immune regulation with implications for vaccination, chronic infection, and immune aging.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.