CD248 expression on mesenchymal stromal cells is required for post-natal and infection-dependent thymus remodelling and regeneration
The role of mesenchymal stromal cells (MSCs) in regulating immune responses in the thymus is currently unclear. Here we report the existence and role of a MSC population in the thymus that expresses the pericyte and MSC marker CD248 (endosialin). We show using a CD248-deficient mouse model, that CD248 expression on these cells is required for full post-natal thymus development and regeneration post-Salmonella infection. In CD248−/− mice the thymus is hypocellular and regeneration is poorer, with significant loss of all thymocyte populations. This identifies the requirement of CD248 to maintain optimal thymic cellularity post-partum and infection.Highlights▸ The mesenchymal stromal cell marker CD248 is expressed in the thymus on pericytes. ▸ Genetic deletion of CD248 prevents full post-natal development of the thymus. ▸ Genetic deletion of CD248 prevents infection-dependent regeneration following thymic atrophy. ▸ CD248 regulates blood endothelial vessel formation in the thymus.