Frade R, Barel M, Ehlin-Henriksson B, Klein G
Proc Natl Acad Sci U S A. 1985 Mar;82(5):1490-3. doi: 10.1073/pnas.82.5.1490.
The relationship between gp140, the membrane C3d receptor (CR2) of human B lymphocytes, and the Epstein-Barr virus receptor (EBVR) was analyzed by using the polyclonal anti-gp140, previously prepared by immunizing rabbits with highly purified gp140 (isolated by some of us) from CR2/EBVR-positive Raji cells. Polyclonal anti-gp72, a C3-binding membrane component, not related to the EBVR but also expressed on the Raji cell surface, was used as a control. Binding of rabbit IgG and EBV on cells was assessed by using immunofluorescence techniques with analysis by flow cytofluorometry. A semiquantitative bioassay was also used to measure the EBV binding. Polyclonal monospecific anti-gp140 IgG inhibits directly the binding of EBV to Raji cells at the same concentration that inhibits the binding of EC3d on cells, whereas a 35 times higher concentration of anti-gp72 IgG or preimmune serum IgG does not. Anti-gp140 IgG treatment also inhibits the induction of EBV-determined nuclear antigen in normal tonsil B lymphocytes or in EBV-negative Ramos cells, whereas high concentrations of anti-gp72 IgG or preimmune serum IgG have no effect. These data strongly suggest that gp140, the CR2 of human B lymphocytes, is also the EBVR.
利用多克隆抗gp140分析了人B淋巴细胞的膜补体C3d受体（CR2）gp140与爱泼斯坦-巴尔病毒受体（EBVR）之间的关系。该多克隆抗gp140是先前用从CR2/EBVR阳性的拉吉细胞中高度纯化的gp140（由我们中的一些人分离得到）免疫兔子制备的。多克隆抗gp72作为对照，gp72是一种与EBVR无关但也表达于拉吉细胞表面的C3结合膜成分。通过使用免疫荧光技术结合流式细胞荧光术分析来评估兔IgG和EBV在细胞上的结合。还使用了一种半定量生物测定法来测量EBV的结合。多克隆单特异性抗gp140 IgG在抑制细胞上EC3d结合的相同浓度下，直接抑制EBV与拉吉细胞的结合，而抗gp72 IgG或免疫前血清IgG浓度高35倍时则无此作用。抗gp140 IgG处理还抑制正常扁桃体B淋巴细胞或EBV阴性的 Ramos细胞中EBV决定的核抗原的诱导，而高浓度的抗gp72 IgG或免疫前血清IgG则无作用。这些数据有力地表明，人B淋巴细胞的CR2 gp140也是EBVR。
