The prolongation of xenograft survival with human natural xenoantibody elimination

猪对人异种移植的超急性排斥反应是由人天然异种抗体（XNA）与猪血管内皮上的α - 1,3 Gal （α - Gal）表位相互作用引起的。预防超急性排斥反应的策略之一是通过静脉输注含有低聚糖的α半乳糖来中和XNA。我们已经用化学方法从半乳糖中合成了含有α -半乳糖的低聚糖，但化学合成耗时长，成本高。利用α - d -半乳糖苷酶，以低成本从咖啡豆中提取二糖-硝基-3-0- α半乳糖基- α半乳糖苷（pnp - α Gal）。用小鼠层粘连蛋白酶联免疫吸附法检测该合成物质对XNA的抑制能力。pnp - α Gal抑制了XNA与层粘连蛋白的结合，也抑制了化学合成的α Gal。此外，我们制作了吸收XNA的猪甲状腺球蛋白（PTg）柱，并试图利用合成的低聚糖制作更有效、更特异性的消除XNA的柱。利用磁珠包被PTg，我们区分了具有α - Gal表面免疫球蛋白的B淋巴细胞和其他B细胞。我们将估计能够合成XNA的B淋巴细胞的比例，并检查它们在来自脾、外周血、肠系膜淋巴结、扁桃腺的人类淋巴细胞中的分布。此外，通过激活这些B细胞自身PHA和几个有丝分裂原，我们将建立（XNA）专门产生的系统。

Hyperacute rejection in xenotransplantation of pig to human is initiated by the interaction of human natural xenoantibodies (XNA) with Gal alpha 1,3 Gal (alpha Gal) epitopes on pig vascular endothelium. One of the strategies for preventing hyperacute rejection is to neutlize XNA by intravenous infusion of alpha Gal containing oligosaccharides. We have synthesized the alpha Gal containing oligosaccharides from galactose by chemical methods, but the chemical synthesis took a great deal of time and required high cost. So we made the disaccharide rho-nitrophenyl-3-0-alpha galactopyranosyl-alpha galactopyranoside (pNP-alpha Gal) using hydrolytic enzyme i.e.alpha-D-Galactosidase from coffee beans at low cost. The ability of this synthetic substance at inhibiting XNA was wxamined by mouse laminin ELISA.pNP-alpha Gal inhibited binding of XNA to laminin as well as chemical synthesized alpha Gal.In addition, we made porcine thyroglobulin (PTg) column which absorbed the XNA,and tried to make the more effective and more specificitic column to eliminate the XNA using the synthesized oligosaccharides. Using magnetic beads coated with PTg, we distinguished B lymphocytes having surface immunoglobulin for alpha Gal from the other B cell. We will estimate the proportion of B lymphocytes capable of synthesizing XNA and examine the distribution of them in human lymphocytes from the spleen, peripheral blood, mesenteric lymph nodes, tonsil gland. Moreover, by activating these B cells with self PHA sup and several mitogen, we are going to establish the system in which (XNA) is exclusively produced.