Sidman C L, Unanue E R
J Immunol. 1978 Dec;121(6):2129-36.
We have utilized several methods to isolate populations of murine splenic B lymphocytes bearing different classes of surface Ig molecules. Antibody and complement-mediated cytotoxicity was used to remove IgD-bearing B cells, and fluorescein-conjugated anti-IgM and polyspecific anti-Ig-F(ab')2 antibody fragments were used with a fluorescence-activated cell sorter to isolate cell bearing IgM or all Ig classes. First, the technique of isolating cells in the sorter was evaluated. It was found that among cells sorted as negative for Ig there was always a certain percentage where IgM reappeared on the membrane after overnight culture. Second, evidence is presented that surface IgM is present on the controls the proliferation of the majority of B lymphocytes in an adult mouse spleen. This includes cells bearing predominantly IgM and cells bearing predominantly IgD. Finally, a theory of B cell stimulation is presented, based on distinctive roles for surface IgM and IgD molecules, as well as a balance between their signals to an individual cell.
我们运用了多种方法来分离带有不同类别表面免疫球蛋白（Ig）分子的小鼠脾脏B淋巴细胞群体。抗体和补体介导的细胞毒性用于去除携带IgD的B细胞，荧光素偶联的抗IgM和多特异性抗Ig-F(ab')2抗体片段与荧光激活细胞分选仪一起用于分离携带IgM或所有Ig类别的细胞。首先，对分选仪中细胞分离技术进行了评估。发现在分选的Ig阴性细胞中，总有一定比例的细胞在过夜培养后膜上会重新出现IgM。其次，有证据表明表面IgM存在于成年小鼠脾脏中大多数B淋巴细胞增殖的对照细胞上。这包括主要携带IgM的细胞和主要携带IgD的细胞。最后，基于表面IgM和IgD分子的独特作用以及它们向单个细胞发出信号之间的平衡，提出了一种B细胞刺激理论。
