Diminished LIGHT-KO donor T cells in BDF1 recipient mice. (A) BDF1 mice were injected intravenously with 5 × 107 spleen cells from WT or LIGHT-KO B6 mice. After 9 days, spleen and liver from the BDF1 recipients were harvested and stained with anti–H-2Kd mAb, together with either anti–CD4 or anti–CD8 mAb. Percentage of donor (H-2Kd-negative) CD4+ or CD8+ T cells in total spleen or liver lymphocytes is shown in the panels. (B) As in panel A, absolute numbers of donor T cells in the recipient spleen were examined at 7 and 9 days after donor cell transfer. Each column shows the number of WT donor T cells (▪) or LIGHT-KO donor T cells (□) as average ± SD. Representative data of 5 independently performed experiments are shown.