Cutting edge: Contribution of NK cells to the homing of thymic CD4(+)NKT cells to the liver

In contrast to peripheral lymphoid organs, in the liver a high proportion o f T cells are CD4(+)NKT cells. We have previously reported that LFA-1 plays a pivotal role in the homing of thymic CD4(+)NKT cells to the liver. In th e present study, we further assessed which cell type participates in the ho ming of thymic CD4(+)NKT cells to the liver. The accumulation of donor thym ocyte-derived CD4(+)NKT cells in the liver of SCID mice that had been recon stituted with thymocytes from C57BL/6 mice was severely impaired by in vivo depletion of NK cells, but not Kupffer cells in recipients. These results suggest that NK cells participate in the homing of thymic CD4(+)NKT cells t o the liver. We assume that LFA-1 expressed on NK cells is involved in this mechanism.