A significant M infiltration is observed in other aggressive B-cell lymphomas such as in Burkitt's lymphoma (BL), in which Ms are functionally involved in neoplastic apoptotic cell engulfment and are stimulated by IL-10 to the synthesis and release of B-cell trophic factors such as BAFF/BLyS [15]. The gene discussed is TNFSF13B; the disease is Burkitt lymphoma.