Targeting of OX40L and GVHD lethality.

Targeting of OX40L regulates GVHD lethality. (A) B10.BR recipients (n = 8 per group per experiment) were lethally irradiated and BM reconstituted, and cohorts of mice were given supplemental splenocytes (25 × 10⁶) as indicated. Splenocyte recipients were administered irrelevant (▴) or anti-OX40L (▵) mAb beginning 1 day prior to transplantation. Data from 2 replicate experiments with similar results are pooled. (B) BALB/c OX40L^−/−mice (dotted lines) or OX40L^+/+ (solid lines) littermate controls (n = 8 per group per experiment), as indicated, were lethally irradiated and BM reconstituted, and cohorts were given B6 purified T cells (10⁶). Data from 2 replicate experiments with similar results are pooled. (C) The 129/Sv OX40L^−/−mice or OX40L^+/+ littermate controls (n = 5 per group), as indicated, were lethally irradiated and reconstituted with B10.BR BM, and cohorts were given purified B10.BR T cells (10⁶). In each instance, targeting of OX40L had a significant impact on GVHD lethality.