Prolongation of Skin Xenograft Survival with Modified Cultured Fibroblasts

Abstract

Cyclosporine A, one of the most potent immunosuppressive drugs, mediates some of its immunosuppressive and nephrotoxic effects by enhancing transforming growth factor-beta secretion and receptor expression. In this experimental study, the effect of cyclosporine pretreatment of cultured dermal fibroblasts on xenogeneic tissue rejection after microimplantation beneath skin grafts was investigated. The effects of the site-specific immunosuppressive strategy on skin xenograft survival were tested. Because the skin is an immunological indicator of the rejection of composite tissue allografts, it was considered that this strategy could be used as a supportive therapy for composite tissue allotransplantation in the future. In the first stage of the study, fibroblast cultures obtained from skin biopsy samples from five rats were treated with different single doses of cyclosporine (100 to 3000 ng/ml), and transforming growth factor-beta levels were measured in culture supernatants after 72 hours. In the second stage, 60 Sprague-Dawley rats were divided into six groups, as follows. For group I (sham), only the standard grafting procedure was performed. For group II, after the standard grafting procedure, rats were treated with intraperitoneal injections of 30 mg/kg (n = 5) or 10 mg/kg (n = 5) cyclosporine for 10 days. For group III, cultured fibroblasts obtained from skin biopsy samples from rats were treated with 100 or 500 ng/ml cyclosporine, and the cells were collected by light trypsinization and centrifugation after 72 hours. After the standard skin grafting procedure, modified fibroblasts were implanted between the graft and the recipient bed with a Pasteur pipet. For group IV, the same procedures as for group III were performed and then rats were treated with 10 mg/kg cyclosporine, administered intraperitoneally, for 10 days. For group V, in addition to standard grafting, unmodified fibroblasts (not treated with cyclosporine) were implanted between the graft and the recipient bed. For group VI, the same procedures as for group V were performed and then rats were treated with 10 mg/kg cyclosporine, administered intraperitoneally, for 10 days. The rejection process was observed macroscopically, and statistical significance was determined with the Mann-Whitney test (p < 0.01). Graft survival times were significantly prolonged in groups III and IV, compared with groups I, II, V, and VI (p < 0.001). No difference between groups III and IV was observed. The novel finding of this investigation is that xenogeneic skin graft survival times could be prolonged with microimplantation of cyclosporine-treated cultured fibro-blasts.

Tolerance Induction in Composite Facial Allograft Transplantation in the Rat Model

“…19 Short-term administration of high-dose cyclosporine A failed to achieve long-term survival of transplanted composite tissue and skin graft allotransplantations, however, as the allotransplants rejected shortly after cessation of the immunosuppressive treatment. 20,21 Previous reports on low-dose cyclosporine A therapy in composite tissue allograft transplantation models did not confirm long-term survival of composite tissue transplants. 22,23 We have modified this approach on our hemiface transplant model by using a high induction dose of cyclosporine A, which was then tapered to the low maintenance dose.…”

Promotion of skin wound healing using hypoimmunogenic epidermal cell sheets

“…There are contradictory data on the survival and immunological response of allografts of cultivated skin cells, particularly fibroblasts and keratinocytes [ [28] , [29] , [30] ]. As with other cell types [ 31 ], however, xenogeneic fibroblasts and keratinocytes have been demonstrated to elicit a robust immunological response in the host [ 30 , 32 , 33 ]. Determine whether IDO has a function in preventing the immunological rejection of transplanted skin cells.…”

Development and Maintenance of Donor-Specific Chimerism in Semi-Allogenic and Fully Major Histocompatibility Complex Mismatched Facial Allograft Transplants

“…In an attempt to minimize the occurrence of these toxic side effects, low-dose and short-term CsA treatment protocols were introduced, but they failed to maintain long-term allograft survival (31,32). In our current study the immunosuppressive protocol was designed with a high induction dose of CsA monotherapy, which was tapered to a low maintenance dose.…”