ILCs and T Cells Competing for Space: More Than a Numbers Game.
T cell homeostasis critically depends on interleukin-7 (IL-7). In this issue of Immunity, Martin et al. (2017) provide evidence that IL-7 availability is regulated through a "cytokine sink" involving innate lymphoid cells that compete for and consume IL-7 and thereby restrict T cell homeostasis in lymphoid organs.
Epithelium‐specific MyD88 signaling, but not DCs or macrophages, control acute intestinal infection with Clostridium difficile
Infection with Clostridium difficile is one of the major causes of health care acquired diarrhea and colitis. Signaling though MyD88 downstream of TLRs is critical for initiating the early protective host response in mouse models of C. difficile infection (CDI). In the intestine, MyD88 is expressed in various tissues and cell types, such as the intestinal epithelium and mononuclear phagocytes (MNP), including DC or macrophages. Using a genetic gain-of-function system, we demonstrate here that restricting functional MyD88 signaling to the intestinal epithelium, but also to MNPs is sufficient to protect mice during acute CDI by upregulation of the intestinal barrier function and recruitment o…