The Impact On The Immunogenicity Of Allogenouscartilage Grafts Stored In Different Crypreservation

ObjectiveTo compare the impact on the immunogenicity of allogenous cartilage graft stored by slow cooling gradient store method, Co60-irradiation with cooling gradient store method and vitrification store method. Then an optimal preservative method lays the foundation of improving the successful rate of allogenous cartilage transplants.MethodsThe fresh cartilages were randomly divided into four groups: A group (control group, not to take any measures), B group (slow cooling gradient group), C group (vitrification group) and D group (Co60-irradiation with cooling gradient group). There were 160 specimens'cartilages to dividing into two parts in each group. One part was directly studied after sacrifice. 10 specimens'cartilages were selected when saving 8 days, 15 days and 30 days. Then chondrocyte was separated and cultured in vitro and made cell suspension. Another 10 10 specimens'cartilages were done at same time. Then cell suspension mixed with the IFN-γwas induced MHC-Ⅱ. We used immunohistological tequenology to label cell surface MHC-Ⅰa nd MHC-Ⅱ. The expression rate of chondrocyte'MHC-Ⅰand MHC-Ⅱw as measured by flow cytometry.Results1. After preservation, the rate of MHC-I antigen expression on chondrocyte surface was significantly decreased in B group, C group, and D group, but there were no significant differences (P> 0.05). There was significant difference comparing with group A (P< 0.05).2. After induction of IFN-γ, chondrocyte surface could express MHC-II antigen in each group. The rate of MHC-Ⅱantigen expression on chondrocyte surface was decreased in varying degrees in each group after preservation. Among the total, the rate of MHC-Ⅱantigen expression on chondrocyte surface was significantly decreased in B group, C group, and D group, but there were no significant differences (P> 0.05). Of course, there was significant difference comparing with A group (P< 0.05).3. After preservation, the rate of MHC-I and MHC-Ⅱantigen expression on chondrocyte surface were no significant differences (P> 0.05) in three crypreservation groups of 30 days and 60 days.Conclusion1. Allogenous cartilage graft immunogenicity was significantly decreased after a variety of methods of preservation. So, these methods can improve the successful rate of allogenous cartilage transplants.2. The immunogenicity of articular cartilage in allogenous cartilage graft could be weaken by slow cooling gradient store method, Co60-irradiation with cooling gradient store method and vitrification store method, and no significant differences in a variety of methods.3. There was no significant differences on the immunogenicity of allogenous cartilage graft in all groups of 30 days and 60 days.