miR-31: the double-edged sword of CD8 T lymphocytes

MicroRNAs (miRNAs) are small regulatory molecules that control gene expression. During the immune response, both initiation and resolution of the response must be tightly regulated to achieve a successful clearance of the infectious agent, avoiding excessive activation that could be detrimental for the host. T cell activation comprises a plethora of signaling pathways that promote expansion and differentiation of the T cell repertoire into effector and memory cells. Moreover, T cells can become exhausted and even dysfunctional under certain circumstances. However, the precise mechanisms that control these processes are only starting to be elucidated. Not surprisingly, microRNAs have important roles in the control of T cell biology and function.