Levin A S, Fudenberg H H, Hopper J E, Wilson S K, Nisonoff A
Proc Natl Acad Sci U S A. 1971 Jan;68(1):169-71. doi: 10.1073/pnas.68.1.169.
Two distinct paraproteins (IgG(2)-K and IgM-K) from one patient shared identical light chains and significant portions of the variable regions of the heavy chains. Idiotypic determinants on the IgG and IgM molecules were shared. Earlier studies, using class-specific antisera, showed that these paraproteins were produced by two different populations of cells. The present study, using rhodamine and fluorescein conjugates of the anti-idiotype antisera, demonstrates that all plasma cells that contain immunoglobulin, whether IgG or IgM, stained with anti-idiotype antisera; this occurred irrespective of whether the antisera were made originally against the patient's IgG or IgM. This, plus previous data, indicates that both populations of cells share genetic information for the constant and variable regions of light chains and significant portions of the heavy-chain genes. These, and other cited data, strongly suggest the occurrence of a switch-over from IgM to IgG synthesis in the same cell during the course of the normal immune response.
来自一名患者的两种不同的副蛋白（IgG(2)-K和IgM-K）共享相同的轻链以及重链可变区的大部分区域。IgG和IgM分子上的独特型决定簇是共享的。早期使用类特异性抗血清的研究表明，这些副蛋白是由两个不同的细胞群体产生的。本研究使用抗独特型抗血清的罗丹明和荧光素缀合物，证明所有含有免疫球蛋白的浆细胞，无论是IgG还是IgM，都能用抗独特型抗血清染色；无论抗血清最初是针对患者的IgG还是IgM制备的，都会出现这种情况。这一点，加上先前的数据，表明这两个细胞群体共享轻链恒定区和可变区以及重链基因大部分区域的遗传信息。这些以及其他引用的数据强烈表明，在正常免疫反应过程中，同一细胞内会发生从IgM合成到IgG合成的转换。
