Expression of a Vα14Jα18 TCR-α transgene fails to drive iNKT cell maturation in Fnip1−/− mice. (A) Thymocytes from control and Fnip1−/−
Vα14Jα18 transgenic, mice were analyzed by flow cytometry with the indicated antibodies. Representative FACS dot-plots are shown from three mice per group. *P < 0.05 (unpaired t test). (B) Thymocytes from WT and Fnip1−/− mice were stained with antibodies specific for CD44, CD24, NK1.1, TCR-β, and the CD1d tetramer. The mean ± SEM percentage and cell number of Stage 0 CD44−CD24+NK1.1− tetramer-positive cells is graphed (n = 13 mice per group). (C) Real-time PCR analysis of TCR-α rearrangement (Vα14 or Vα3 to Jα56, Jα18, or Jα9) in FACS-sorted DP thymocytes from Fnip1−/− and WT mice. Shown is the mean ± SEM from three mice per group. mRNA expression standardized to Cα loading is shown.