Figure 4.

TEC subsets in hCD3ɛ transgenic thymi transplanted under the kidney capsule of hCD3ɛ transgenic or RAG-1^−/− recipients. Newborn hCD3ɛ transgenic thymi were transplanted under the kidney capsule of adult hCD3ɛ transgenic or RAG-1^−/− mice as described in Materials and Methods. Four weeks later the transplanted thymi were recovered and double-stained for K8 (green) and K5 (red) or single-stained for CD25. The original magnification was ×200 except for the inset, which was ×600. The thymi recovered from the hCD3ɛ transgenic retained a K8⁺K5⁺ phenotype, whereas thymi recovered from RAG-1^−/− recipients contained both K8⁺K5⁺ and K8⁺K5⁻ subsets as well as CD25⁺ thymocytes.