Boué D R, Lebien T W
Department of Laboratory Medicine and Pathology, University of Minnesota Medical School, Minneapolis 55455.
J Immunol. 1988 Jan 1;140(1):192-9.
CD22 and CD21 are glycoproteins primarily expressed on normal and neoplastic human B cells. The surface expression of these two molecules parallel each other during normal B cell differentiation, and the reported relative mobilities for CD22 and CD21 are 130/140 kDa and 140 kDa, respectively. Herein we present a detailed analysis of the biosynthesis and structure of CD22 and also compare it directly to CD21. Electrophoresis under reducing and nonreducing conditions suggested that CD22 and CD21 may have similarities in intra-chain disulfide bond formation. Biosynthesis and processing of CD22 and CD21 were very similar with respect to kinetics and post-translational modification, and both could be phosphorylated. However, endoglycosidase digestion (using N-glycanase and endoglycosidase H) and peptide mapping (using V8 protease and N-chlorosuccinimide) strongly suggested that CD22 and CD21 are distinct gene products.
CD22和CD21是主要在正常和肿瘤性人类B细胞上表达的糖蛋白。在正常B细胞分化过程中，这两种分子的表面表达相互平行，报道的CD22和CD21的相对迁移率分别为130/140 kDa和140 kDa。在此，我们对CD22的生物合成和结构进行了详细分析，并将其与CD21直接进行比较。还原和非还原条件下的电泳表明，CD22和CD21在链内二硫键形成方面可能具有相似性。CD22和CD21的生物合成和加工在动力学和翻译后修饰方面非常相似，并且两者都可以被磷酸化。然而，内切糖苷酶消化（使用N-糖苷酶和内切糖苷酶H）和肽图谱分析（使用V8蛋白酶和N-氯代琥珀酰亚胺）强烈表明CD22和CD21是不同的基因产物。
