IL-4 Induced Innate CD8+ T Cells Control Persistent Viral Infection

Memory-like cd8+ t cells expressing eomesodermin are a subset of innate t cells initially identified in a number of genetically modified mice,and also exist in wild mice and human. the acquisition of memory phenotype and function by these t cells is dependent on il–4 produced by plzf+ innate t cells; however,their physiologic function is still not known. here we found that these il-4-induced innate cd8+ t cells are critical for accelerating the control of chronic virus infection. in ciita-transgenic mice,which have a substantial population of il-4-induced innate cd8+ t cells,this population facilitated rapid control of viremia and induction of functional anti-viral t-cell responses during infection with chronic form of lymphocytic choriomeningitis virus. characteristically,anti-viral innate cd8+ t cells accumulated sufficiently during early phase of infection. they produced a robust amount of ifn-γ and tnf-α with enhanced expression of a degranulation marker. furthermore,this finding was confirmed in wild-type mice. taken together,the results from our study show that innate cd8+ t cells works as an early defense mechanism against chronic viral infection. © 2015 lee et al.