IG GENETICS--ONTOGENY AND DIFFERENTIATION OF CELLS OF THE RABBIT IMMUNE SYSTEM

尽管含有K2同型轻链的Ig分子很少(如果有的话) 都是由我们的实验室兔子生产的，我们演示了转录 对K2基因进行了S1保护分析和轻链大小的mRNA分析 用K2特异的合成寡核苷酸探针进行Northern分析。 同样，尽管突变的巴西兔只产生很少的或根本没有免疫球蛋白 J1-b9型轻链，我们检测到低水平的b9RNA。我们 正在调查这是否是异常拼接的消息，因为我们已经 发现Basilea兔的K1-b9基因在 J-C内含子的剪接受体位点。用类似的方法，我们没有 然而，检测到的与b5相对应的mRNA或基因组DNA序列 血清学上观察到的由b9/b9细胞产生的同种异型 用b5、抗b9和脂多糖进行体外培养。因此，另一种解释 对于潜伏的同种异型的血清学观察，必须援引。我们有 还表明，合成的寡核苷酸来自第一和第三 重链可变区的骨架区域(FR1和FR3) 具体区分a1和a2兔产生的mRNAs。这个 然而，原型FR1和FR3序列可能不完全与 血清学上可检测到的VHA决定因素。一群兔子携带着 Basilea突变体的亲本染色体已经被 发现并证明具有限制性片段长度多态 在Basilea兔中也发现了K2基因的(RFLP)。这允许链接 猪瘟病毒K1表型、K2 RFLP和一种新发现的RFLP的研究 兔T细胞受体链恒定区基因。我们已经分析和 预测了kappa轻链异型决定簇的位置。 预测的决定因素是外部的，位于循环中或附近，并落入 两个潜在相互作用的区域簇，其中有几个 可能会出现多组重叠的表位。抗K1抗体的相互作用 具有这种表位的抗体免疫球蛋白抗体半抗原抗体消失 半抗原介导的抗体与抗原偶联细胞的解离。

Although few, if any, Ig molecules bearing light chains of the K2 isotype are produced by our laboratory rabbits, we demonstrated transcription of the K2 gene by S1 protection analyses and light-chain sized mRNA by northern analysis with a K2-specific synthetic oligonucleotide probe. Similarly, although mutant Basilea rabbits produce little or no Igs with light chains of the J1-b9 type, we have detected low levels of b9 RNA. We are investigating whether this is aberrantly spliced message since we have found that the K1-b9 gene in Basilea rabbits has a point mutation in the splice acceptor site of the J-C intron. With similar methods, we have not however, detected mRNA or genomic DNA sequences corresponding to the b5 allotype that has been observed serologically to be produced by b9/b9 cells cultured in vitro with b5 anti-b9 and LPS. Thus alternative explanations for serological observations of latent allotypes must be invoked. We have also shown that synthetic oligonucleotides from the first and third framework regions (FR1 and FR3) of variable regions of heavy chains specifically distinguish mRNAs produced by a1 and a2 rabbits. The prototype FR1 and FR3 sequences may not, however, completely correlate with serologically detectable VHa determinants. A strain of rabbits carrying the parental chromosome from which the Basilea mutant was derived has been developed and shown to have a restriction fragment length polymorphism (RFLP) of the K2 gene also found in Basilea rabbits. This allows linkage studies of the K1 phenotype, K2 RFLP and a newly discovered RFLP of the rabbit T cell receptor chain constant region gene. We have analyzed and predicted the locations of kappa light chain allotypic determinants. Predicted determinants were external, located in or near loops, and fell in two clusters of potentially interacting regions within which several overlapping sets of epitopes could occur. Interaction of anti-K1 antibodies with such epitopes on IgG anti-hapten antibodies abolished hapten-mediated dissociation of the antibody from haptgen-coupled cells.