B-cell–deficient μMT mice have normal professional APC numbers and function. Splenocytes were phenotyped from naive μMT and wild-type mice. (A) Proportions of APCs within spleen. (B) Absolute numbers of APCs within spleen. Results represent mean ± SE (n = 3, *P < .05). (C) Purified Balb/c T cells were cultured with allogeneic μMT and wild-type B6 irradiated splenocytes. Proliferation was measured via ³H-thymidine incorporation. Results represent 1 of 3 identical experiments. (D) Purified Balb/c T cells were cultured with allogeneic μMT and wild-type B6 CD11c⁺ DCs, and proliferation was determined by ³H-thymidine incorporation. Results represent mean ± SE of triplicate wells and 1 of 2 replicate experiments.