精液源性病毒感染增强因子（SEVI），能增强HIV感染。我们前期研究表明，SEVI也可能是导致"多聚阴离子类杀微生物剂"预防HIV性传播临床试验失败的重要原因。因此，SEVI成为艾滋病预防生物制剂研究的关键因素和新靶点。本课题组前期研究发现：①兔抗SEVI IgG能有效降低SEVI的病毒感染增强作用，但自身抗HIV活性并不明显；②酸酐修饰卵清蛋白具很强抗HIV活性，但因其带负电荷可能与SEVI作用而活性降低。综上两项研究，本项目拟用酸酐修饰抗SEVI多抗，希冀其因被酸酐修饰而具有直接抑制病毒感染，也可通过其抗体功能区与SEVI多肽结合而拮抗SEVI介导的对HIV感染增强作用，从而制备出一种双功能杀微生物剂。本课题将评价该酸酐修饰抗体本身及在精液或SEVI多肽存在下抗HIV活性，深入研究其与SEVI的相互作用，分析其对SEVI淀粉样纤维形成的影响，为艾滋病预防用杀微生物剂研发奠定基础。

Semen-derived Enhancer of Virus Infection （SEVI） can enhance HIV infection. Our previous studies showed that SEVI may be one of the important factors resulting in failure of clinical trials of the polyanionic microbicides for preventing sexual transmission of HIV. Therefore, SEVI should be one of the key targets in developing preventive anti-HIV microbicides. Recently, we demonstrated that rabbit anti-SEVI IgG could effectively reduce SEVI-mediated enhancing effect of HIV infection. But itself had no significant anti-HIV activity. We previously found that anhydride-modified ovalbumin (OVA) and many other proteins exhibited strong anti-HIV activity. Based on these findings, we will design and prepare an anhydride-modified anti-SEVI antibody as a dual-functional microbicide for preventing HIV sexual transmission. It is expected that the anhydride-modified anti-SEVI antibody can not only strongly bind to HIV through its increased negative charge and inhibit HIV replication, but also effectively reduce SEVI-mediated HIV enhancing effect via its anti-SEVI domains. We will evaluate the anti-HIV activity of anhydride modified anti-SEVI antibody in the presence of semen or SEVI peptide, Furthermore, we will study the interaction between anhydride modified anti-SEVI antibody and SEVI and analyze its effect on SEVI amyloid fibril formation. This study will provide a foundation for development anti-HIV prevention drugs.