Figure 1. SAP plays a critical role in T-CD4 T cell development.

(A) CIITA-expressing thymocytes can efficiently select WT CD4 T cells. CIITA^Tg (Tg) BM (CD45.1) were mixed with WT BM (CD45.1/2) and co-transferred to the MHC class II deficient Aβ^-/- hosts (CD45.2). Thymocytes, LN and splenic cells from chimeric mice were analyzed for T cell repopulation by Tg and WT BM. The numbers in the dot plots indicate the percentages of gated CD4 and CD8 T cells of each BM driven cells. Data are representative of 5 mice.

(B) Percentages of CD4 (top graph) and CD8 (bottom graph) in Tg+WT^-/-→Aβ^-/- chimeric mice. Data are shown as mean ± SD from 5 mice. * and ** indicates p<0.05 and p<0.01, respectively.

(C) SAP is necessary for T-CD4 T cell selection. Tg (CD45.1/2) and SAP^-/- (CD45.2) BM were co-transferred to Aβ^-/- (CD45.1) recipients (left group). As a control, WT (CD45.1/2) and SAP^-/- (CD45.2) BM were used to reconstitute B6 (CD45.1) hosts (right group). CD4 and CD8 populations in thymi, LN, and spleens by cells derived from the indicated BM source were shown. The numbers in the dot plots are the percentages of gated CD4 and CD8 cells of each BM driven cells.

(D) Percentages of CD4 (top panels) and CD8 (bottom panels) cells in Tg+SAP^-/-→Aβ^-/- (right groups) and WT+SAP^-/-→WT (left groups) chimeric mice. Data are shown as mean ± SD from 4 Tg+SAP^-/-→Aβ^-/- mice and 2 WT+SAP^-/-→WT mice.

(E) Percentage of thymic NK1.1⁺TCRβ⁺ NKT cells from different BM in Tg+SAP^-/-→Aβ^-/- (left two panels) and WT+SAP^-/-→B6 chimeras (right two panels). Numbers indicate the percentages of NKT cells among total thymocytes.