Splenic stromal niches in homeostasis and immunity

In the spleen, diverse types of fibroblastic stromal cells, as well as neuronal cells, establish a complex microanatomy that supports splenic function at homeostasis and orchestrates immune responses to infection. The spleen is a gatekeeper of systemic immunity where immune responses against blood-borne pathogens are initiated and sustained. Non-haematopoietic stromal cells construct microanatomical niches in the spleen that make diverse contributions to physiological spleen functions and regulate the homeostasis of immune cells. Additional signals from spleen autonomic nerves also modify immune responses. Recent insight into the diversity of the splenic fibroblastic stromal cells has revised our understanding of how these cells help to orchestrate splenic responses to infection and contribute to immune responses. In this Review, we examine our current understanding of how stromal niches and neuroimmune circuits direct the immunological functions of the spleen, with a focus on T cell immunity.

Automated summary

In the spleen, a complex microanatomy consisting of fibroblastic stromal cells and neuronal cells supports splenic function and immune responses. The spleen plays a crucial role in initiating and sustaining immune responses against blood-borne pathogens. Stromal cells in the spleen construct microanatomical niches that contribute to physiological spleen functions and regulate immune cell homeostasis. Recent understanding of splenic fibroblastic stromal cell diversity has improved our knowledge of how these cells orchestrate splenic responses to infection and contribute to immune responses. This review focuses on the role of stromal niches and neuroimmune circuits in directing T cell immunity in the spleen.