0000000000019023
AUTHOR
James T. Walsh
Understanding the Role of T Cells in CNS Homeostasis.
T cells within the central nervous system (CNS) have been generally considered pathogenic, especially in the context of neuroinflammatory disease. However, recent findings have revealed varied functions for T cells in the healthy CNS, as well as more complex roles for these cells in infection and injury than previously appreciated. Here we review evidence indicating important roles for different T cell subsets in the maintenance of CNS homeostasis. We examine the contribution of T cells in limiting inflammation and damage upon CNS injury, infection, and in neurodegeneration, and discuss the current understanding of the cellular and molecular mechanisms involved. Insight into these processes…
MHCII-independent CD4+ T cells protect injured CNS neurons via IL-4
A body of experimental evidence suggests that T cells mediate neuroprotection following CNS injury; however, the antigen specificity of these T cells and how they mediate neuroprotection are unknown. Here, we have provided evidence that T cell-mediated neuroprotection after CNS injury can occur independently of major histocompatibility class II (MHCII) signaling to T cell receptors (TCRs). Using two murine models of CNS injury, we determined that damage-associated molecular mediators that originate from injured CNS tissue induce a population of neuroprotective, IL-4-producing T cells in an antigen-independent fashion. Compared with wild-type mice, IL-4-deficient animals had decreased functi…