Involvement of CD16 in antibody-dependent enhancement of porcine reproductive and respiratory syndrome virus infection

• DOI: 10.1099/vir.0.000118
• Publication Date: 2015-03-10T01:42:22Z
• Authors: Weihong Gu; Li Feng; Haidong Yu; Zhijun Tian; Mingming Huang; Yue Wang; Junwei Niu; Xiaolei Luo; Longjun Guo; Ren Li
• Keywords: Swine; Blotting, Western; Receptors, IgG; Virus Attachment; Antigen-Antibody Complex; Virus Internalization; Flow Cytometry; Real-Time Polymerase Chain Reaction; Antibody-Dependent Enhancement; Cell Line; 3. Good health; 03 medical and health sciences; 0302 clinical medicine; Macrophages, Alveolar; Animals; Porcine respiratory and reproductive syndrome virus; Protein Binding

The immunological effect of porcine reproductive and respiratory syndrome disease virus (PRRSV) vaccines is thought to be influenced by a variety host factors, in which antibody-dependent enhancement (ADE) infection one crucial factor. Here, we assessed the mechanism ADE PRRSV infection. First, found that subneutralizing serum could induce alveolar macrophages (PAMs). Quantitative PCR, Western blotting flow cytometry revealed CD16 most abundant Fcγ receptor (FcγR) expressed on surface PAMs; thus, role was examined PAMs. By using functional blocking antibodies, demonstrated involved enhanced production PRRSV-antibody immune complex-infected Because PAMs co-express different FcγR isoforms, evaluated effects FcγR-non-bearing cells transfection. Using these engineered cells, specifically bind complex subsequently mediate internalization virus, resulting generation progeny virus. We also showed efficient expression required association FcR γ-chain. Together, our findings provide significant new insights into infection, can CD16-mediated complexes. This may shift tropism towards CD16-expressing distributing more organs during