B6 recipients were primed on day −56 with 20 × 10⁶ BALB/c splenocytes intraperitoneally. Splenectomy (Splx) was performed on day −28. Mouse Ig (20 mg) was administered intraperitoneally on day −15 and day −7. In vivo TCD was achieved by intraperitoneal administration of 400 μg anti-CD4 and anti-CD8 mAbs on days −2, 0, 2, 4, and 7. Mice were irradiated with 6.0 Gy on day −1 and infused with 100 × 10⁶ BALB/c BM on day 0. All deaths occurred within 2 weeks after transplantation. All engrafted mice were more than 90% donor by peripheral blood leukocyte phenotyping 3 months after BMT.

P < .01 versus primed, no treatment (primed, TCD, Ig vs primed, TCD, Ig, Splx; P = .32.).