THE ROLES OF NOVEL LECTINS IN HOST DEFENSE SYSTEM FOUND IN RABBIT SERA.

我们已经在兔和人血清中发现了新的凝集素和凝集素样蛋白。识别寡糖结构、血型H型和血型2（Fuc α 1-2 Gal β 1-3/4 GlcNAc β）和N-乙酰乳糖胺的兔血清凝集素（RSL-I）凝集人红细胞。兔血清凝集素的纯化采用亲和层析的Synsorb H 2型珠，凝胶过滤和制备聚丙烯酰胺凝胶电泳。经凝胶过滤和SDS-聚丙烯酰胺凝胶电泳测得凝集素的分子量分别为650000和65000。PG结合蛋白结合到Sephacryl S凝胶上，通过凝胶过滤和制备型聚丙烯酰胺凝胶电泳容易地纯化。PG结合蛋白可凝集人红细胞，其血凝反应可被磷脂酰化酶抑制 ...更多信息 甘氨酸和磷脂酰甘油）和神经节苷脂（GM 3）。为了阐明这种蛋白在体内的作用，我们检测了对细菌的抑制或控制活性。结果表明，该蛋白对革兰氏阴性菌无抗菌活性，但对某些革兰氏阴性菌有凝集活性，其分子量为86 kDa和59 kDa，呈二硫键多聚体结构，在人血清中发现了类似PG结合蛋白（抗PLHu抗体），该蛋白对Sephacryl S凝胶有亲和性，并能凝集兔红细胞。血凝反应被磷脂（磷脂酰丝氨酸和磷脂酰肌醇）特异性抑制，但不被任何其他磷脂、神经节苷脂、磷脂酰胆碱抑制。此外，该蛋白还能引起豚鼠补体对兔红细胞的溶血，因此这些结果表明，兔和人血清中的凝集素和凝集素样蛋白可能在对抗细菌病原体的免疫保护中发挥重要作用。少

We have found novel lectin and lectin-like proteins in rabbit and human sera. A rabbit serum lectin (RSL-I) which recognized oligosaccharide structures, blood group H type land type2 (Fuc alpha 1-2 Gal beta 1-3/4 GlcNAc beta) and N-acetyllactosamine agglutinated human red blood cells. The rabit serum lectin was purified using affinity chromatography on Synsorb H type 2 beads, gel filtration and preparative polyacrylamide gel electrophoresis. The molecular weight of the lectin was calculated to be approximate 650000 and 65000 on gel filtration and SDS-polyacrylamide gel eletrophoresis.Moreover we have isolated and purified a novel phospholipid/ganglioside-binding protein (PG-binding protein) from rabbit sera. The PG-binding protein bound to Sephacryl S gel and was easily purified by gel filtration and preparative polyacrylamide gel electrophoresis. The PG-binding protein agglutinated human red blood cells, and its hemagglutination reaction was inhibited by phospholipids (phosphatidylser … More ine and phosphatidylglycerol) and ganglioside (GM3). In order to clarify the role of this protein in body, we examined the inhibitory or control activity for bacteria. It did not have any antibacterial activity, but has agglutination activity for some Gram's negative bacterias.The protein seemed to be assembled as multimers of disulfide-bonded molecular of 86 kDa and 59 kDa subunits.The resemble PG-binding protein (antiPLHu-antibody) was found in human sera, and the protein had affinity for the same Sephacryl S gel and agglutinated rabbit red blood cells. The hemagglutination reaction was specifically inhibited by phospholipids (phosphatidylserine and phosphatidylinositol) but not any other phospholipids, gangliosides, saccharides. Furthermore, the protein was able to cause hemolysis of rabbit red blood cells with guinea pig complement.Thus these results suggest that lectin and lectin-like protein in rabbit and human sera might have important roles of the immunological protection against bacterial pathogens. Less