title: Use of anti-CD3 epsilon F(ab')2 fragments in vivo to modulate graft-versus-host disease without loss of graft-versus-leukemia reactivity after MHC-matched bone marrow transplantation.
abstract: The use of T cell-specific mAb in vivo for prevention and treatment of graft-vs-host disease (GVHD) and its impact on graft-vs-leukemia (GVL) reactivity was examined in a murine model of MHC-matched bone marrow transplantation (BMT). F(ab')2 fragments of a CD3 epsilon-specific mAb were administered to irradiated AKR (H-2k) hosts after transplantation of BM plus spleen cells from B10.BR donors (BMS chimeras). The effects on GVH and GVL reactivity were Ab dose- and schedule-dependent. A short course of mAb (qe2d, days 0 to 8) prevented clinical evidence of GVHD and mortality. Anti-CD3 F(ab')2 mAb reversed clinical symptoms of acute GVHD when delayed up to 18 days post-transplant. Anti-host (Mls-1a)-specific V beta 6+ cells were absent from the spleens of GVH-negative control mice, but persisted in Ab-treated BMS chimeras despite the absence of GVHD. Leukemic mice given 16.7 micrograms of Ab on days 0, 2, and 4 survived leukemia-free without developing severe GVHD. A longer course of Ab completely prevented GVHD, but led to leukemia relapse in tumor-bearing hosts, despite engraftment of donor T cells. The GVL effect was quantitatively stronger when Ab was used for GVH therapy as compared with GVH prevention. Some Ab-treated, GVH-free chimeras relapsed with lymphomas in unusual sites, suggesting that occult tumor cells may persist in nonlymphoid tissues. These experiments demonstrate that T cell-specific mAb can be used successfully in vivo to avoid severe GVHD, but that excessive or ill-timed administration of Ab may eliminate GVL reactivity.
authors.affiliation: Department of Pediatrics, Medical College of Wisconsin, Milwaukee 53226, USA.
authors.forename: B D
authors.initials: BD
authors.lastname: Johnson
authors.forename: C
authors.initials: C
authors.lastname: McCabe
authors.forename: C A
authors.initials: CA
authors.lastname: Hanke
authors.forename: R L
authors.initials: RL
authors.lastname: Truitt
mesh_terms: D000818:Animals; D016026:Bone Marrow Transplantation / Q000276:immunology*; D005260:Female; D005434:Flow Cytometry; D006086:Graft vs Host Disease / Q000517:prevention & control*; D007140:Immunoglobulin Fab Fragments / Q000627:therapeutic use*; D007942:Leukemia, Experimental / Q000628:therapy*; D051379:Mice; D008806:Mice, Inbred AKR; D008815:Mice, Inbred Strains; D011828:Radiation Chimera / Q000276:immunology; D017260:Receptor-CD3 Complex, Antigen, T-Cell / Q000276:immunology*; D011948:Receptors, Antigen, T-Cell / Q000276:immunology*
chemical_list: D007140:Immunoglobulin Fab Fragments; D017260:Receptor-CD3 Complex, Antigen, T-Cell; D011948:Receptors, Antigen, T-Cell; C061836:antigen T cell receptor, epsilon chain