Figure 3. The E protein transcription factors contribute to CCR9 expression on primary T cell progenitors.

(A) FACS analysis for CCR9 on CD25⁻ and CD25⁺ Lin⁻CD45⁺GFP⁺ FL MPPs culture in vitro for 3 days prior to infection with MigR1 or MigR1-ID2 retrovirus and treated with DMSO (shaded histogram) or GSI (open histogram) on day 5 for 48hrs. The frequency of CCR9⁺ cells on GSI (black) or DMSO (grey) treated cells is indicated. One of four representative experiments is shown. (B) Average ⁺ standard deviation of the percent of CD25⁻ and CD25⁺ Lin⁻CD45⁺GFP⁺ cells expressing CCR9 after treatment as in (A). n=4, ** = p<0.01 and *** = p<0.001. (C) FACS analysis for CCR9 protein on Lin⁻CD44⁻CD117⁻CD25⁻ DN4 thymocytes and CD4⁺CD8⁺ DP thymocytes isolated from an E2A^+/+ or E2A^−/− mouse. One of three experiments is shown. (D) FACS analysis for CCR9 protein on DP thymocytes from a Cd4^Cre/- or Cd4^Cre+/-Heb^f/f mouse.