Lymphoblastoid cell adhesion mediated by a dimeric and polymeric endogenous beta-galactoside-binding lectin (galaptin).
Lymphoblastoid cell adhesion mediated by a dimeric and polymeric endogenous beta-galactoside-binding lectin (galaptin).
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由二聚体和聚合体内源性 β-半乳糖苷结合凝集素（galaptin）介导的淋巴母细胞粘附。
DOI：
10.1002/jmr.300050102
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发表时间：
1992
期刊：
影响因子：
--
通讯作者：
Allen,HJ
中科院分区：
文献类型：
--
作者：
Ahmed,H;Sharma,A;DiCioccio,RA;Allen,HJ
戊二醛聚合的人脾半乳糖凝集素（一种β-半乳糖苷结合凝集素）被证明在溶液中存在时，相对于天然二聚半乳糖凝集素具有增强的血凝和脱唾液酸胎球蛋白结合活性。聚合凝集素在还原烷基化后主要由2-、4-和12-元物种组成。两种形式的半乳糖肽在4 °C下均与可饱和的B类淋巴母细胞表面受体结合。通过Scatchard分析获得的估计值（结合数据以14.5 kDa亚基摩尔浓度表示）为5 × 107个结合位点/细胞（亲和力常数Ka= 2.2 × 105 M）（对于二聚体半乳糖肽）和17 × 107个结合位点/细胞（亲和力常数Ka = 3.4 × 105 M − 1）（对于聚合体半乳糖肽）。两种形式的半乳糖肽均高效吸附于聚苯乙烯;然而，仅塑料吸附的聚合半乳糖肽介导淋巴母细胞样细胞的粘附。细胞粘附被乳糖抑制。塑料吸附的聚合半乳糖肽比二聚半乳糖肽更有效地结合脱唾液酸胎球蛋白。对于塑料吸附的聚合半乳糖肽和二聚半乳糖肽，乳糖分别抑制脱唾液酸胎球蛋白结合65%和30-50%，天然胎球蛋白以乳糖不敏感的方式与吸附的二聚半乳糖肽结合。这些数据表明，细胞表面受体-半乳糖苷肽相互作用是碳水化合物特异性的，而聚苯乙烯吸附的半乳糖苷肽可能表明蛋白质-蛋白质与可溶性配体的相互作用。
Glutaraldehyde‐polymerized human splenic galaptin, a β‐galactoside‐binding lectin, was demonstrated to have enhanced hemagglutinating and asialofetuin binding activity relative of native dimeric galaptin when these lectins were present in solution. The polymerized lectin consisted primarily of 2‐, 4‐ and 12‐membered species after reductive alkylation. Both forms of galaptin bound, at 4 °C, to saturable B lymphoblastoid cell surface receptors. Estimates obtained by Scatchard analyses, with the binding data expressed in terms of 14.5 kDa subunit molarity, were 5 × 107binding sites/cell with affinity constant Ka= 2.2 × 105Mfor dimeric galaptin and 17 × 107binding sites/cell withKa= 3.4 × 105M−1for polymeric galaptin. Both forms of galaptin adsorbed to polystyrene with high efficiency; however, only plastic‐adsorbed polymeric galaptin mediated adhesion of lymphoblastoid cells. Cell adhesion was inhibited by lactose. Plastic‐adsorbed polymeric galaptin bound asialofetuin more efficiently than dimeric galaptin. Asialofetuin binding was inhibited 65% and 30–50% by lactose for plastic‐adsorbed polymeric and dimeric galaptin, respectively, Native fetuin bound to the adsorbed dimeric galaptin in a lactose‐insensitive manner. These data indicate that cell surface receptor‐galaptin interaction is carbohydrate specific whereas polystyrene‐adsorbed galaptin may demonstrate protein‐protein interactions with soluble ligands.