Custom Monoclonals International, West Sacramento, CA 95691, USA.
Proc Natl Acad Sci U S A. 2009 Nov 24;106(47):19980-5. doi: 10.1073/pnas.0911307106. Epub 2009 Nov 9.
We analyzed antibody responses in sera from feline immunodeficiency virus (FIV)-infected and uninfected cats. A strong antiviral response to the viral surface glycoprotein (SU) was noted in both natural and experimental infections. In addition, 143 of 226 FIV-infected animals (63%) also expressed antibodies to the primary binding receptor, CD134, whereas cats infected with other feline RNA viruses, including calicivirus, coronavirus, herpesvirus, and feline leukemia virus, did not. Both affinity-purified anti-CD134 and anti-SU antibodies blocked FIV infection ex vivo. FACS analyses revealed that the anti-CD134 antibodies bound to a cryptic epitope on the receptor that was only exposed when SU bound to CD134. Anti-CD134 binding caused displacement of SU from the surface of the cell and inhibition of infection. The presence of antibodies to CD134 correlated with lower virus loads and a better overall health status in FIV(+) cats, whereas anti-SU antibodies were present independent of health status. The findings are consistent with a role for antireceptor antibodies in protection from virus spread and disease progression.
我们分析了感染和未感染猫免疫缺陷病毒（FIV）的血清中的抗体反应。在自然和实验感染中，均观察到针对病毒表面糖蛋白（SU）的强烈抗病毒反应。此外，226 只 FIV 感染动物中有 143 只（63%）还表达了针对主要结合受体 CD134 的抗体，而感染其他猫 RNA 病毒（包括杯状病毒、冠状病毒、疱疹病毒和猫白血病病毒）的猫则没有。亲和纯化的抗 CD134 和抗 SU 抗体均可在体外阻断 FIV 感染。FACS 分析显示，抗 CD134 抗体与受体上的隐蔽表位结合，只有当 SU 与 CD134 结合时，该表位才会暴露。抗 CD134 结合导致 SU 从细胞表面移位并抑制感染。抗 CD134 抗体的存在与 FIV(+)猫中较低的病毒载量和更好的整体健康状况相关，而抗 SU 抗体的存在则与健康状况无关。这些发现与抗病毒传播和疾病进展的抗受体抗体的作用一致。
