Reconstitution of splenic structure (A) and of mucosal IgA-producing plasma cells (B) after wild-type bone marrow transplantation in TNF-LT
(A) Distinct separation of T and B cell areas and germinal center formation after transplantation of wild-type bone marrow cells (2 × 106 cells) into irradiated TNF-LTα knock-out recipient mice. Clearly demarcated B220-positive B cell follicles (a) and CD3-positive T cell areas (b). By contrast, wild-type mice transplanted with mutant bone marrow cells show little distinction between splenic T and B cell areas, as B220-positive B cells (c) and CD3-positive T cells (d) are interdispersed. (B) Repopulation of the lamina propria of the ileum with IgA-producing plasma cells. While TNF-LTα knock-out mice have no IgA producing plasma cells in the lamina propria (a), TNF-LTα knock-out mice reconstituted with wild-type bone marrow cells have a repopulation with IgA-producing cells (b) resembling the wild-type control mice (c).