Clarke S H, Claflin J L, Potter M, Rudikoff S
J Exp Med. 1983 Jan 1;157(1):98-113. doi: 10.1084/jem.157.1.98.
Complete variable (V) region amino acid sequences were determined for four heavy (H) and one light (L) chain from C57BL phosphocholine (PC)-binding monoclonal antibodies. Additional NH2-terminal sequences were obtained from H and L chains of C57BL and CBA/J origin. When these V regions were compared with previously reported anti-PC sequences, a number of observations could be made regarding the function and evolution of L and H chain segments used in these antibodies. (a) L and H chain V segments are remarkably conserved in these inbred strains, although there has been an accumulation of point mutations identifying apparently allelic forms of VK and VH. (b) Mice of each genotype use the same three VK segments in combination with a single VH segment to produce most anti-PC antibodies. An exception has been noted that indicates the occasional use of a second VH gene segment. (c) Multiple, different DH regions are used by mice of each strain, which suggests that the DH segment sequence plays no critical role in either antigen binding or VH-VL pairing. Furthermore, the DH segments and their corresponding gene families appear to be highly conserved in the inbred strains studied. (d) Most PC-binding antibodies use the JH1 joining segment. All JH1 sequences from C57BL mice differ from the BALB/c JH1 at position 105, which identifies allelic forms of the JH1 region. These studies are a first assessment of the nature of mutational events associated with the evolution of specific multigene immunoglobulin families and indicate that homologous VH, DH, JH, VK, and JK genes are similarly assembled and expressed in PC antibodies from three diverse genotypes.
测定了来自C57BL磷酸胆碱（PC）结合单克隆抗体的四条重链（H）和一条轻链（L）完整可变（V）区的氨基酸序列。还获得了来自C57BL和CBA/J品系的H链和L链的额外氨基末端序列。当将这些V区与先前报道的抗PC序列进行比较时，可就这些抗体中使用的L链和H链片段的功能和进化得出一些观察结果。（a）尽管已经积累了一些点突变，这些点突变确定了VK和VH明显的等位基因形式，但在这些近交系中，L链和H链V片段非常保守。（b）每种基因型的小鼠使用相同的三个VK片段与单个VH片段组合，以产生大多数抗PC抗体。已注意到一个例外情况，即偶尔会使用第二个VH基因片段。（c）每个品系的小鼠使用多个不同的DH区域，这表明DH片段序列在抗原结合或VH-VL配对中均不发挥关键作用。此外，在所研究的近交系中，DH片段及其相应的基因家族似乎高度保守。（d）大多数PC结合抗体使用JH1连接片段。来自C57BL小鼠的所有JH1序列在第105位与BALB/c JH1不同，这确定了JH1区域的等位基因形式。这些研究是对与特定多基因免疫球蛋白家族进化相关的突变事件性质的首次评估，并表明同源的VH、DH、JH、VK和JK基因在来自三种不同基因型的PC抗体中以相似的方式组装和表达。
