Kaneko Yoshikatsu, Nimmerjahn Falk, Ravetch Jeffrey V
Laboratory of Molecular Genetics and Immunology, Rockefeller University, 1230 York Avenue, New York, NY 10021, USA.
Science. 2006 Aug 4;313(5787):670-3. doi: 10.1126/science.1129594.
Immunoglobulin G (IgG) mediates pro- and anti-inflammatory activities through the engagement of its Fc fragment (Fc) with distinct Fcg receptors (FcgRs). One class of Fc-FcgR interactions generates pro-inflammatory effects of immune complexes and cytotoxic antibodies. In contrast, therapeutic intravenous gamma globulin and its Fc fragments are anti-inflammatory. We show here that these distinct properties of the IgG Fc result from differential sialylation of the Fc core polysaccharide. IgG acquires anti-inflammatory properties upon Fc sialylation, which is reduced upon the induction of an antigen-specific immune response. This differential sialylation may provide a switch from innate anti-inflammatory activity in the steady state to generating adaptive pro-inflammatory effects upon antigenic challenge.
免疫球蛋白G（IgG）通过其Fc片段（Fc）与不同的Fcγ受体（FcγRs）结合来介导促炎和抗炎活性。一类Fc-FcγR相互作用产生免疫复合物和细胞毒性抗体的促炎作用。相比之下，治疗性静脉注射丙种球蛋白及其Fc片段具有抗炎作用。我们在此表明，IgG Fc的这些不同特性源于Fc核心多糖的差异唾液酸化。Fc唾液酸化后，IgG获得抗炎特性，而在诱导抗原特异性免疫反应时，这种唾液酸化会减少。这种差异唾液酸化可能提供了一个从稳态下的先天性抗炎活性到抗原刺激后产生适应性促炎作用的转换机制。
