Roles of B cells in naive T-cell proliferation in lymphopenic conditions. (A) Groups of TCRβ−/− mice were injected intravenously with 18B12 (B cell depleting) or 2B8 (isotype control) Abs (250 μg per recipient). Splenic B cells were analyzed by CD19 staining 7 days after the Ab injection. (B) TCRβ−/− recipients injected with 18B12, 2B8, or none received 106 Thy1.1 naive CD4 and CD8 T cells 7 days after the Ab injection. Donor cell recovery was calculated 7 days after T-cell transfer. Each symbol represents individual recipient mice. (C) The ratio of adoptively transferred donor cells in the indicated tissues was analyzed. (D) CFSE profiles of donor Thy1.1 cells within TCRβ−/− recipients treated with antibodies are shown. The results are representative of at least 3 individual mice per group. (E) Splenic B cells were cotransferred (5 × 106 cells) together with naive T cells into Rag1−/− recipients. After day 7, the ratio of adoptively transferred donor cells in the spleen, LN, and mesenteric LN was analyzed by staining Ly5.1 and CD4. Each symbol represents individual recipient mice.
