FIGURE 8.

NKT cell proliferation in β₂m^−/− mice is caused by β₂m-independent CD1d. Spleen NK1.1⁺ cells and LPS-stimulated spleen B cells were obtained from WT and β₂m^−/− mice as described in Materials and Methods and cultured in the presence of 3C11 anti-CD1d mAb or isotype control mAb. The NKT cells were labeled with CFSE, and B cell-induced proliferation was measured by staining and gating on TCRβ⁺ NKT cells and assessing CFSE expression. Treatment with anti-CD1d mAb, but not isotype control mAb, inhibited the proliferation of NKT cells induced by B cells from β₂m^−/− mice and WT mice.