犬瘟热病毒基因变异及其细胞受体研究进展

Genetic variations and cellular receptors of Canine distemper virus—— A review

摘要:

由犬瘟热病毒（Canine distemper virus, CDV）引起的犬瘟热（CD）一直是对世界养犬业、毛皮动物养殖业以及野生动物保护事业危害最为严重的传染病之一，甚至在广泛应用疫苗防制CD的近年，世界各地仍有犬或野生动物感染CDV并造成CD流行的报道。通过对CDV主要抗原基因—— 血凝基因（H基因）氨基酸序列分析，CDV可分为6个基因型。研究证实，CDV野毒株在抗原性上与疫苗株存在较大差异，因此推测H蛋白抗原变异造成了弱毒疫苗免疫效力的降低进而导致了某些地区CD的爆发。CDV作为一种宿主范围广泛的病毒，其细胞受体—— 信号淋巴细胞激活因子（SLAM）和硫酸乙酰肝素（HS）在哺乳动物体内的广泛存在是CDV跨物种间感染的重要因素。本文就国内外最新研究进展并结合作者的工作，对上述问题进行了综述和探讨。

Abstract:

Canine distemper (CD) caused by Canine distemper virus (CDV) was first reported in 1905, and has been one of the most serious contagious diseases of dogs as well as other carnivores. Recently, increasing cases of canine distemper (CD) both in vaccinated and unvaccinated dogs and in wildlife have been reported in Japan, America, Europe and Africa. Based on phylogenetic analysis of the hemagglutinin (H) gene sequences, six genotypes of CDV were distinguished. Antigenic heterogeneity of the H protein that provides an important protective antigen against CDV infection has been observed between wild-type CDV and vaccine strains. So it was suspected that the vaccines currently used can no longer efficiently protect animal from present-day circulating CDV infection. The host range of CDV includes all species of the families Canidae and many other species. Both signaling lymphocyte activation molecule (SLAM) and heparin sulfate (HS) expressed on the cells of the immune system or other non-lymphoid tissues can act as the cellular receptors for CDV, and are one of the major determinants of the host range and tissue tropism. In this review, we discussed the above-mentioned issues based on the recent research progress and the studies in our laboratory.