Casu R, Eisemann C, Pearson R, Riding G, East I, Donaldson A, Cadogan L, Tellam R
Commonwealth Scientific and Industrial Research Organization (CSIRO) Tropical Agriculture, CSIRO P.M.B. 3, Indooroopilly, 4068 Queensland, Australia.
Proc Natl Acad Sci U S A. 1997 Aug 19;94(17):8939-44. doi: 10.1073/pnas.94.17.8939.
Many insects feed on blood or tissue from mammalian hosts. One potential strategy for the control of these insects is to vaccinate the host with antigens derived from the insect. The larvae of the fly Lucilia cuprina feed on ovine tissue and tissue fluids causing a cutaneous myiasis associated with considerable host morbidity and mortality. A candidate vaccine antigen, peritrophin 95, was purified from the peritrophic membrane, which lines the gut of these larvae. Serum from sheep vaccinated with peritrophin 95 inhibited growth of first-instar L. cuprina larvae that fed on this serum. Growth inhibition was probably caused by antibody-mediated blockage of the normally semipermeable peritrophic membrane and the subsequent development of an impervious layer of undefined composition on the gut lumen side of the peritrophic membrane that restricted access of nutrients to the larvae. The amino acid sequence of peritrophin 95 was determined by cloning the DNA complementary to its mRNA. The deduced amino acid sequence codes for a secreted protein containing a distinct Cys-rich domain of 317 amino acids followed by a mucin-like domain of 139 amino acids. The Cys-rich domain may be involved in binding chitin. This report describes a novel immunological strategy for the potential control of L. cuprina larvae that may have general application to the control of other insect pests.
许多昆虫以哺乳动物宿主的血液或组织为食。控制这些昆虫的一种潜在策略是用源自昆虫的抗原对宿主进行疫苗接种。绿蝇 Lucilia cuprina 的幼虫以绵羊组织和组织液为食，导致一种皮肤蝇蛆病，会使宿主出现相当高的发病率和死亡率。一种候选疫苗抗原——围食膜蛋白95，是从这些幼虫肠道内衬的围食膜中纯化出来的。用围食膜蛋白95接种疫苗的绵羊血清抑制了取食该血清的一龄 Lucilia cuprina 幼虫的生长。生长抑制可能是由抗体介导的对正常情况下具有半渗透性的围食膜的阻断引起的，随后在围食膜肠腔侧形成了一层成分不明的不透水层，限制了幼虫获取营养。通过克隆与其 mRNA 互补的 DNA 确定了围食膜蛋白95的氨基酸序列。推导的氨基酸序列编码一种分泌蛋白，该蛋白包含一个由317个氨基酸组成的独特的富含半胱氨酸结构域，后面跟着一个由139个氨基酸组成的粘蛋白样结构域。富含半胱氨酸的结构域可能参与结合几丁质。本报告描述了一种潜在控制 Lucilia cuprina 幼虫的新型免疫策略，该策略可能普遍适用于控制其他害虫。
