猪肝细胞膜蛋白结构与异种移植细胞免疫反应原性的关系

The relation between conformation of cell membrane proteins and immunoreactivity of xenotransplanted cells

探讨猪肝细胞膜蛋白结构与异种移植细胞免疫反应原性的关系。方法：肝衰大鼠分为冻存细胞移植值，新鲜细胞移植组和对照组，腹腔内分别移植新鲜和冻存的猪肝细胞，记录鼠的存活率。圆二色光谱测定新鲜和冻存猪肝细胞的膜蛋白构象，抗体依赖性细胞毒性试验检测肝细胞破损情况。

To study the relation between conformation of cell membrane proteins and immunoreactivity of xenotransplanted cells. Methods: Rats with acute hepatic failure (AHF) were divided into 3 group; one of cryopreserved hepatocyte transplant (17 rats), one of fresh cell transplant (9 rats) and a control one (9 rats) which was not transplanted by the hepatocytes. The fresh and cryopreserved porcine hepatocytes were respectively transplanted into the abdominal cavities of Wistar rats with AHF, and the survival rates of the rats were observed. The conformation of membrane proteins of the fresh and cryopreserved porcine hepatocytes was calculated from their circular dichroism spectra. The destruction of the cells was assayed by antibody-dependent cellular cytotoxicity (ADCC). Results: The survival rate of rats in control group was 33. 3 %, and that in fresh hepatocyte transplant group was 66. 7%. The survival rate of rats in the cryopreserved cell transplant group increased to 94.1%, which was significantly higher than that of the control (P = 0. 002 2). α-helix content in the membrane proteins of fresh cells was 47. 5 %. After treated by liquid nitrogen, the content increased to 56.5 %. The ADCC showed that the number of the fresh hepatocytes survived was 0. 24 × 10~5, and that of the frozen cells survived was 0. 68 ×10~5. Conclusion: Decrease of immunoreactivity of xenotransplant cells was related to the increase of the α-helix content in the membrane proteins of the