Study On The Feasibility Of Establishing Nude Mice Model Of Thymoma-associated Myasthenia Gravis

Objective To explore the tumor tissue in nude mice survival status, and its influence the T lymphocytes cell immunity and complement activity. It is illustrated the feasibility of establishing of thymoma associated myasthenia gravis animal model, and provide the basis model for the study of pathogenesis of thymoma and myasthenia gravis.Methods 6 cases of thymoma associated myasthenia gravis patients from July 2014 to January 2015, Cardiothoracic Surgery Department of General Hospital Affiliated to Tianjin Medical University, and postoperative pathology confirmed the diagnosis of type of B thymoma. By cutting tail in nude mice peripheral blood were collected for flow cytometric detection of T lymphocyte and its subsets and the enzyme linked immunosorbent assay method was used to detect the level of total serum complement. Under sterile conditions, tumor tissue specimens were obtained by sterile operation, the blade cut into pieces of 1-2mm3, Through the operation mode of the tissue blocks were transplanted into 36 nude mice of BALB/c left renal subcapsular. The 90 day after transplantation respectively through the eyeball by peripheral blood T lymphocytes and their subsets change detection and the total content of complement, and then were sacrificed by cervical dislocation mice, remove the left kidney, observe the tumor tissue survival. The transplanted nude mice peripheral blood T lymphocytes and its subsets and the total complement content changes were statistically analyzed by using the paired t test method.Results 1、 Thymoma tissues were survival in BALB/c nude mice transplanted under the kidney capsule, the tumor tissue were seen in BALB/c nude mice transplanted under the capsule of kidney. We found that the tumor tissue had a clear structure, no ischemia, necrosis, no significant increase. Immunohistochemical staining showed that the tumor tissue were survival in renal tissue, but the success rate was 61%.2、 BALB/c nude mice peripheral blood T lymphocyte subsets are changes before and after transplantation. The results of flow cytometry showed after transplantation the percentage of CD3+T lymphocytes and the percentage of CD4+T cells were significantly increased compared with before transplantation, the difference was statistically significant(P<0.05), the percentage of CD8+T cells after transplantation was lower compared before transplantation, the difference was statistically significant(P<0.05).3、 The changes are in BALB/c nude mice peripheral blood Serum levels of total complement. The enzyme linked immunosorbent assay results showed that after transplantation of peripheral serum total complement content are decreased compared before the transplantation, the difference was statistically significant(P<0.05).Conclusion 1、 Human-derived thymoma as long-term heterografts survival in BALB /c nude mice.2、 BALB/c nude mice have a complete complement system, and can play a role.3、 Thymoma transplanted tissue blocks have an impact on mice peripheral blood T lymphocytes and their subsets, manifested as increased proportion of CD3+T lymphocytes and CD4+T lymphocytes, CD8+T lymphocyte ratio decreased. Indicating thymoma tissue in nude mice play part thymic function, affect mice cellular immunity, and the cellular immunity may be reconstruction.The need for research to understand the subpopulation of cells and function to play for the proportion of CD4+T cell subsets.4、 Establishment of animal model of thymoma associated myasthenia gravis type is feasible, and provide the basis for studying animal models of the pathogenesis of thymoma and myasthenia gravis.