title: Vascularized osteochondral allografts in an immunosuppressed rat model: graft modulation and host immune tolerance.
abstract: The effects of 4 weeks of cyclosporin A (7 mg/kg per day) (CyA) on the survival of vascularized osteochondral grafts between rat strains [DA (donor) and Lewis (recipient)] and the presence and significance of host immune tolerance and graft antigen modulation after cessation of immunosuppression have been examined. Isografts (n = 12) survived without apparent abnormality for 8 weeks but showed signs of wasting after longer periods; unprotected allografts (n = 5) were rejected within 2 weeks. After 4 weeks of CyA, allografts remained healthy for at least 12 weeks but then deteriorated (n = 40). Antigen modulation was examined by graft removal at various intervals after cessation of CyA and reimplantation into a naive recipient (n = 14). All were rejected rapidly. Host tolerance was examined by graft removal at various periods after cessation of CyA and reimplantation of a fresh allograft (n = 15). Some of the second grafts survived at least 4 weeks without immunosuppression. The findings indicate development of incomplete host tolerance but no antigenic modulation of the graft.
authors.affiliation: Microsurgery Research Centre, St. Vincent's Hospital, Melbourne, Australia.
authors.forename: K
authors.initials: K
authors.lastname: Sakai
authors.forename: M J
authors.initials: MJ
authors.lastname: Hickey
authors.forename: J V
authors.initials: JV
authors.lastname: Hurley
authors.forename: N
authors.initials: N
authors.lastname: Kuwata
authors.forename: A J
authors.initials: AJ
authors.lastname: d'Apice
authors.forename: B M
authors.initials: BM
authors.lastname: O'Brien
authors.forename: L I
authors.initials: LI
authors.lastname: Arnold
authors.forename: P A
authors.initials: PA
authors.lastname: Abbey
mesh_terms: D000818:Animals; D016025:Bone Transplantation / Q000276:immunology*; D002356:Cartilage / Q000637:transplantation*; D016572:Cyclosporine / Q000627:therapeutic use*; D006084:Graft Rejection / Q000517:prevention & control*; D006085:Graft Survival / Q000276:immunology*; D007108:Immune Tolerance / Q000276:immunology*; D007165:Immunosuppression Therapy; D051381:Rats; D011917:Rats, Inbred Lew; D013997:Time Factors; D014184:Transplantation, Homologous; D014185:Transplantation, Isogeneic
chemical_list: D016572:Cyclosporine