Novel splenic antigen-presenting cells derive from a Lin^-c-kit^lo progenitor

The main DC subsets in murine spleen arise from BMderived precursors. Recently, a novel APC type was described in spleen. To determine if spleen contains the progenitors of this subset, a stromal coculture system was used to assess candidate progenitors for their hematopoietic potential. Here, the progenitor of that subset is identified as a spleen endogenous Lin^-c-kit^lo hematopoietic progenitor and is most highly enriched among the Lin^-c-kit^loCD34⁺ subset. Dendritic-like cells produced in vitro functionally resemble the previously described in vivo equivalent subset with high endocytic capacity and capability for antigen-specific activation of CD8⁺ T cells but not CD4⁺ T cells.