OBJECTIVETo improve the histocompatibility of chicken calamus keratin (CCK) graft by collagen-gel coating or using of cyclosporine A (CsA).

METHODSThirty SD rats were equally randomized into 5 groups, and in 4 of them, CCK implantation into the bilateral erector spinae was performed on different treatment protocols. In group A, the rats received daily intraperitoneal injection of CsA (5 mg/kg) for two consecutive weeks after CCK implantation; in group B, CCK was soaked in CsA (2.5 mg/ml) solution at 4 degrees Celsius; for 48 h before grafting; in group C, CCK coated with collagen gel was grafted; and in group D, only CCK was implanted. Rats in the fifth group received only cutaneous incision as well as muscular dissection to serve as the blank control. CCK degradation and its effect on the surrounding tissues were observed at 2, 4 and 8 weeks after grafting. Immunohistochemistry was performed to identify T lymphocyte infiltration in the host tissues.

RESULTSAll the rats survived the operation. Numerous macrophages, especially multinucleated giant cells occurred on the peripheral of the CCK grafts, and small degraded CCK pieces were observed in their cytoplasm. Only a few inflammatory cells were seen in the host tissues. At 2, 4 and 8 weeks after CCK implantation, only a few CD3-positive cells were found in all the groups, and in group A and B, the density of T lymphocytes was significantly lower than that in group D, and there was no significant difference between group A and the blank control group.

CONCLUSIONSCsA significantly improves the histocompatibility of CCK material, and short-term systemic CsA administration achieves the best results. Macrophages, especially multinucleated giant cells participate in CCK degradation in vivo.