title: Antibody-mediated rejection of cardiac allografts in CCR5-deficient recipients.
abstract: Rejected MHC-mismatched cardiac allografts in CCR5(-/-) recipients have low T cell infiltration, but intense deposition of C3d in the large vessels and capillaries of the graft, characteristics of Ab-mediated rejection. The roles of donor-specific Ab and CD4 and CD8 T cell responses in the rejection of complete MHC-mismatched heart grafts by CCR5(-/-) recipients were directly investigated. Wild-type C57BL/6 and B6.CCR5(-/-) (H-2(b)) recipients of A/J (H-2(a)) cardiac allografts had equivalent numbers of donor-reactive CD4 T cells producing IFN-gamma, whereas CD4 T cells producing IL-4 were increased in CCR5(-/-) recipients. Numbers of donor-reactive CD8 T cells producing IFN-gamma were reduced 60% in CCR5(-/-) recipients. Day 8 posttransplant serum titers of donor-specific Ab were 15- to 25-fold higher in CCR5(-/-) allograft recipients, and transfer of this serum provoked cardiac allograft rejection in RAG-1(-/-) recipients within 14 days, whereas transfer of either serum from wild-type recipients or immune serum from CCR5-deficient recipients diluted to titers observed in wild-type recipients did not mediate this rejection. Wild-type C57BL/6 and B6.CCR5(-/-) recipients rejected A/J cardiac grafts by day 11, whereas rejection was delayed (day 12-60, mean 21 days) in muMT(-/-)/CCR5(-/-) recipients. These results indicate that the donor-specific Ab produced in CCR5(-/-) heart allograft recipients is sufficient to directly mediate graft rejection, and the absence of recipient CCR5 expression has differential effects on the priming of alloreactive CD4 and CD8 T cells.
authors.affiliation: Glickman Urological Institute, Cleveland Clinic Foundation, OH 44195, USA.
authors.forename: Taiji
authors.initials: T
authors.lastname: Nozaki
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Amano
authors.forename: Alice
authors.initials: A
authors.lastname: Bickerstaff
authors.forename: Charles G
authors.initials: CG
authors.lastname: Orosz
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Novick
authors.forename: Kazunari
authors.initials: K
authors.lastname: Tanabe
authors.forename: Robert L
authors.initials: RL
authors.lastname: Fairchild
mesh_terms: D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D006082:Graft Enhancement, Immunologic; D006084:Graft Rejection / Q000276:immunology* / Q000473:pathology / Q000517:prevention & control; D006085:Graft Survival / Q000235:genetics / Q000276:immunology; D016027:Heart Transplantation / Q000276:immunology*; D007106:Immune Sera / Q000008:administration & dosage; D007116:Immunization, Passive; D007518:Isoantibodies / Q000096:biosynthesis / Q000378:metabolism / Q000502:physiology*; D008213:Lymphocyte Activation / Q000235:genetics / Q000276:immunology; D008231:Lymphopenia / Q000235:genetics / Q000276:immunology / Q000473:pathology; D008297:Male; D051379:Mice; D008805:Mice, Inbred A; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D019713:Receptors, CCR5 / Q000172:deficiency* / Q000235:genetics* / Q000502:physiology
chemical_list: D007106:Immune Sera; D007518:Isoantibodies; D019713:Receptors, CCR5