Figure 5.

Spleen follicle structure in recipients of wild-type or LTα^−/− bone marrow. 6 wk after bone marrow reconstitution, mice were immunized i.p. with SRBC and 10 d later sections of frozen spleen were stained with 8C12 (blue) to detect FDC, and with anti-B220 (brown). Clusters of FDC were detected in both wild-type mice (A) and LTα^−/− mice (B) that had been reconstituted with wild-type BM. Clusters of FDC were not detected in either wild-type (C) or LTα^−/− mice (D) that had received BM from LTα^−/− mice. The GC reaction was assessed by staining spleen sections with PNA (blue) and anti-IgD (brown). GC were observed in both wild-type mice (E) and LTα^−/− mice (F) that had received BM from wildtype donors, but were not detected in either wild-type (G) or LTα^−/− mice (H) that were reconstituted with BM from LTα^−/− donors.