Identification of a New Stromal Cell Type Involved in the Regulation of Inflamed B Cell Follicles

Lymph node (ln) stromal cells provide survival signals and adhesive substrata to lymphocytes. during an immune response,b cell follicles enlarge,questioning how ln stromal cells manage these cellular demands. herein,we used a murine fate mapping system to describe a new stromal cell type that resides in the t cell zone of resting lns. we demonstrated that upon inflammation,b cell follicles progressively trespassed into the adjacent t cell zone and surrounded and converted these stromal cells into cxcl13 secreting cells that in return delineated the new boundaries of the growing follicle. acute b cell ablation in inflamed lns abolished cxcl13 secretion in these cells,while lt-β deficiency in b cells drastically affected this conversion. altogether,we reveal the existence of a dormant stromal cell subset that can be functionally awakened by b cells to delineate the transient boundaries of their expanding territories upon inflammation. © 2013 mionnet et al.