Analysis of Physiological Roles of Novel Immunoglobulin-Like Receptors, PIR

点击翻译按钮获取中文摘要

Paired immunoglobulin-like receptor (PIR)-B inhibits receptor-mediated activation signaling in vitro, while neither the physiological role nor ligand for PIR has been elucidated. PIR-B-/- mice had an increased number of peritoneal B-1 cells with age that, along with splenic B-2 cells, were hypersensitive to B cell receptor ligation. T helper (TH)2-prone humoral responses were augmented in the mutant mice upon immunization with T-dependent antigens in terms of both interleukin-4-rich/interferon-γ-poor cytokine profile and enhanced IgG1 and IgE production. Impaired maturation of dendritic cells possibly due to perturbed intracellular signaling was responsible for the skewing. Thus, PIR-B is critical for B cell suppression, DC maturation, and for balancing TH1/TH2 immune responses.