Investigating the phenotype, function and interactions of tissue-resident B cells (360G-Wellcome-205250_Z_16_Z)

Tissue-specific immunity is shaped by the local milieu. In organ systems that interface with the environment (e.g. skin, gastrointestinal tract), exogenous signals generated by commensals or diet can profoundly influence resident immune cells. In non-interfacing tissues (e.g. kidney), endogenous signals such as interstitial osmolality may also influence the immune landscape. Tissue epithelial cells play an important role as environmental sensors and may instruct local immune responses. In addition, environmental cues may be directly detected by resident immune cells. To date, studies of tissue sentinels have focused on innate immune cells and on T cells with limited data on B cells. We have preliminary data from human and murine kidneys, and from human liver tissue and murine bladder tissue demonstrating the presence of tissue-resident B cells. In humans, they are predominantly of a memory phenotype. We hypothesize that tissue-resident B cells make an important contribution to local immune responses and that their localization and function will be determined by tissue-specific environmental cues. This project aims to investigate the phenotype of these tissue resident B cells (both in mouse and human), their antigenic specificity, origin, function and interaction with other cells.