Manduca sexta lipopolysaccharide-specific immulectin-2 protects larvae from bacterial infection
Manduca sexta lipopolysaccharide-specific immulectin-2 protects larvae from bacterial infection
复制标题
DOI：
10.1016/s0145-305x(02)00099-x
复制
发表时间：
2003-03-01
影响因子：
2.9
通讯作者：
Kanost, MR
中科院分区：
文献类型：
--
作者：
Yu, XQ;Kanost, MR
我们先前报道了从烟草天蛾Manduca sexta中分离脂多糖（LPS）特异性免疫球蛋白-2 [J.Biol.Chem.275（2000）37373]。Immulectin-2是一种C-型凝集素，以组成性低水平存在于幼稚幼虫的血淋巴中，并且其合成在注射革兰氏阴性细菌或LPS后被诱导。Immulectin-2含有两个糖识别结构域。它与LPS结合并刺激血浆中的酚氧化酶原活化。本文主要介绍了immulectin-2的糖识别结构域2的性质及其在免疫应答中的生物学功能。immulectin-2的羧基端碳水化合物识别结构域（CRD 2）能够结合细菌LPS。重组CRD 2与LPS的结合刺激血浆中酚氧化酶原的活化。免疫球蛋白-2抗血清注射M. sexta幼虫抑制革兰氏阴性细菌病原体粘质沙雷氏菌的清除，并降低感染的存活率。这些结果表明immulectin-2在M. sexta，并有助于保护动物免受革兰氏阴性细菌感染。(C)2002爱思唯尔科技有限公司。保留所有权利。
We previously reported the isolation of a lipopolysaccharide (LPS)-specific immulectin-2 from the tobacco hornworm, Manduca sexta [J. Biol. Chem. 275 (2000) 37373]. Immulectin-2 is a C-type lectin that is present at a constitutively low level in hemolymph of naive larvae, and its synthesis is induced after injection of Gram-negative bacteria or LPS. Immulectin-2 contains two carbohydrate recognition domains. It binds to LPS and stimulates prophenoloxidase activation in plasma. In this paper, we focus on properties of carbohydrate recognition domain-2 of immulectin-2 and the biological functions of immulectin-2 in immune responses. The carboxyl-terminal carbohydrate recognition domain (CRD2) of immulectin-2 was able to bind bacterial LPS. Binding of recombinant CRD2 to LPS stimulated activation of prophenoloxidase in plasma. Injection of antiserum against immulectin-2 into M. sexta larvae inhibited clearance of a Gram-negative bacterial pathogen, Serratia marcescens, and decreased survival of infection. These results suggest that immulectin-2 plays an important role in the immune system of M. sexta, and helps to protect the animal from Gram-negative bacterial infections. (C) 2002 Elsevier Science Ltd. All rights reserved.