Figure 3.

Reduced levels of invariant NKT (iNKT) cells in the thymus of ceramide synthase 2 (CerS2)-null mice is due to their impaired maturation in the thymus. (A) Representative flow cytometry plots showing the frequencies of thymocytes (upper panel), CD4⁺CD1d-PBS57 tetramer⁺ iNKT cells (middle panel), and CD3⁺CD1d-PBS57 tetramer⁺ iNKT cells (lower panel) out of total hematopoietic cells in wild-type (WT) and CerS2-null mice. (B) Average percent and absolute number of the indicated cells (n = 5). (C,E) Representative flow cytometry contour plots showing the percent of different developmental stages of iNKT cells in the thymus. (D,F) Average percent of iNKT cells at different developmental stages in the thymus (n = 3). The experiment was repeated two times with similar results. Percents are indicated in red. Black columns, WT; red columns, CerS2 null.