IMMUNOBIOLOGY OF EQUINE INFECTIOUS ANEMIA VIRUS, A RETROVIRUS MODEL FOR AIDS

马传染性贫血病毒(EIAV)在形态上， 在遗传学和血清学上与人类免疫缺陷有关 从而为研究人类免疫缺陷病毒(HIV)提供了一个有用的模型 慢病毒引起的疾病中病毒与宿主的相互作用。 马传染性贫血(EIA)的特点是发作性的 与外观有关的临床疾病的性质 新的病毒变种。这个项目涉及的是 阐明在产生和选择中的重要因素 这些病毒变异和理解变异的作用 在慢病毒的持久性和致病机制上。我们之前的工作 提示在病程早期，EIAV变异体可能 在体内被非免疫机制选择。我们有 因此，开始了体外宿主细胞趋向性的研究。 流行性出血热病毒不同毒株及其与病毒的可能相关性 致病性。分离的病毒被选作体外试验 在连续细胞系中的复制显示出1,000-10,000- 在原代马单核细胞中病毒复制的折叠减少 培养(HMC)与连续细胞系中的复制相比。 此外，这显著减少了马体内的病毒复制 单核细胞，被认为是EIAV复制的目标细胞 活体，与病毒毒力的丧失有关。这表明 在体外HMC中的病毒复制水平可能与 体内致病性。因此，我们加大了努力，以 分离到一个具有复制能力的EIAV分子克隆 作为了解病毒结构特征的基础 在病毒致病性方面很重要。

Equine infectious anemia virus (EIAV) is morphologically, genetically, and serologically related to human immunodeficiency virus (HIV) and thus provides a useful model for the study of virus-host interactions in lentivirus-induced disease. Characteristic of equine infectious anemia (EIA) is the episodic nature of clinical disease which is associated with the appearance of novel viral variants. This project is concerned with elucidating the factors important in the generation and selection of these viral variants and in understanding the role of variation in lentivirus persistence and pathogenesis. Our previous work suggested that early in the course of disease, EIAV variants may be selected in vivo by non-immunological mechanisms. We have therefore initiated studies on the in vitro host cell tropism of various strains of EIAV and its possible correlation with viral pathogenicity. Virus isolated which were selected for in vitro replication in continuous cell lines demonstrated a 1,000-10,000- fold reduction in viral replication in primary horse monocyte cultures (HMC) as compared to replication in continuous cell lines. Moreover, this marked reduction of viral replication in horse monocytes, believed to be the target cell for EIAV replication in vivo, was associated with a loss of viral virulence. This suggest that levels of viral replication in in vitro HMC may be a correlate of in vivo pathogenicity. Thus, we have increased our efforts to isolate a replication-competent molecular clone of EIAV which could serve as a basis for understanding structural viral features important in viral pathogenicity.