FIG. 6.

(A) PCR analysis of TCRβ gene DJ rearrangement. DNA samples were prepared from either total thymocytes or sorted CD25⁺ CD44⁻ DN3 cells of 2- to 3-week-old mice. DJ rearrangement products from the Dβ2 and Jβ2 region were analyzed by PCR with Dβ2 and Jβ2.6 primers. PCR products were blotted and hybridized with a J segment-specific probe. The expected DJ rearrangement products are indicated on the right. Samples in the blot are toe DNA (lane 1), a 1-kb size ladder (lane 2), wild-type total thymocytes (lane 3), HEB^bm/bm total thymocytes (lane 4), HEB^bm/bm DN3 cells (lane 5), and wild-type DN3 cells (lane 6). (B) PCR analysis of TCRβ gene VDJ rearrangement. DNA used in the DJ rearrangement assay were PCR amplified with Vβ8 and Jβ2.6 primers. PCR products with expected Jβ usage are indicated on the left. Samples in the blot are wild-type total thymocytes (lane 1), wild-type DN3 cells (lane 2), HEB^bm/bm total thymocytes (lane 3), and HEB^bm/bm DN3 cells (lane 4). Similar results were obtained with Vβ5 and Jβ2.6 primers.