可溶型猪CD2的分离纯化及其生物化学性质的研究

本文报告可溶型猪E受体的分离纯化及其生物化学性质的研究结果。以羊抗猪CD2的抗体制备亲和层析柱,从猪血清中分离反向玫瑰花实验和免疫双扩散均为阳性的组分后,再经制备SDS—PAGE和电泳洗脱纯化,得到两个猪可溶型CD2(sCD2)分子。其分子量分别为60和29KDa。sCD2在SDS—PAGE和IEF—PAGE 中均呈现单一区带,其等电点分别为6.6和5.5,酶联免疫分析所呈阳性反应。比较研究发现sCD2与膜结合型CD2的生物化学性质不同,前者对一定剂量范围内的ConA 或PHA 诱导的猪外周血淋巴细胞增强具有抑制作用,这种抑制效应具有量效关系,而后者与T 细胞激活有关,文中对两型CD2生物学活性的差别以及sCD2的生物学意义进行了讨论。

Isolation purification and characterization of porcine soluble CD2

Previously we first reported that there is a soluble form of E-receptor (SRBC receptor,CD2)in human and porcine sera.Isolation,purification and characterization of porcine solubleCD2 (sCD2) were presented in this paper.Two molecules of porcine sCD2 with M.W. of 60kDa and 29 kDa,pI of 6.6 and 5.5 respectively,and with inhibitory activity of reverse E -rosetteformation were isolated by affinity chromatography from porcine serum and purified by prepara-tive SDS-PAGE.It was found that the sCD2 possesses homologous biochemical properties butdifferent biological activity compared with the CD2 bound on the lymphocyte membranes.ThesCD2 inhibited proliferation of the porcine lymphocytes induced by Con A in a range of concen-trations.The inhibitory effect was sCD2-dose dependent.However,the membrane-bound formof CD2 is involved inactivation of T lymphocytes.Biological significance of the different biologicalactivities of the two forms of CD2 was discussed.