Lack of permanent TCRγ silencing in innate T cells. (A) Expression of TCRVγ4 mRNA normalized to β-actin in the indicated subpopulations, measured by real time RT-PCR in arbitrary units relative to mature thymocytes (AU). N indicates naive splenocytes TCRγδ⁻TCRβ⁺CD44⁻CD62L⁺; M, memory splenocytes TCRγδ⁻TCRβ⁺CD44⁺CD62L⁺; A, activated splenocytes TCRγδ⁻TCRβ⁺CD44⁺CD62L⁻; T, mature thymocytes TCRγδ⁻TCRβ^hi; and NKT, thymic NKT TCRγδ⁻TCRβ^loNK1.1⁺. (B-C) Analysis of MACS enriched, CD1d^tet+ iNKT cells from the thymus of TCRδ^−/− and CD1d^−/−TCRδ^−/− (B) and the sorted CD1d^tet+ T-cell subsets from TCRδ^−/− mice. (C) Numbers in dot plots show percentages. (D) Expression of TCRVγ4 mRNA normalized to cell number in the indicated subpopulations sorted from TCRδ^−/− and CD1d^−/−TCRδ^−/− mice measured by real-time RT-PCR (see “Two-stage RT-PCR”) in arbitrary units relative to DN thymocytes (AU).