So A K, Lindsay J, Bodmer J, Trowsdale J
Tissue Antigen Laboratory, Imperial Cancer Research Fund Laboratories, London, England.
J Immunol. 1987 Nov 15;139(10):3506-11.
Histocompatibility leukocyte antigen DQ molecules exhibit polymorphism of both DQ alpha- and beta-chains. Histocompatibility leukocyte antigen-DQw3 is associated with both DR4 and DR5 and can be further subdivided by reactivity with the monoclonal antibody TA10. To determine the molecular nature of the DQ polymorphic alleles associated with the DR4 haplotype, we have sequenced and analyzed DQ alpha and beta cDNA clones obtained from a DR4, Dw4, DQw3 cell line which is TA10-positive. The DQ alpha-chain sequence was identical to previously published sequences from the DR4 haplotype, but the DQ beta sequence differed from published DR4-DQ beta sequences obtained from DQw3-positive TA10-negative cell lines by eight amino acids, six of which were located in the beta 1 domain. Thus, the TA10 serologic determinants reside on the DQ beta-chain. A TA10-specific oligonucleotide probe was constructed based on the DQ beta sequence, and its specificity was confirmed in a panel of TA10-positive and TA10-negative cell lines. An additional band was observed in Southern blotting experiments which may indicate a donor sequence for gene conversion.
组织相容性白细胞抗原DQ分子在DQα链和β链上均表现出多态性。组织相容性白细胞抗原-DQw3与DR4和DR5均相关，并且可以通过与单克隆抗体TA10的反应性进一步细分。为了确定与DR4单倍型相关的DQ多态性等位基因的分子性质，我们对从TA10阳性的DR4、Dw4、DQw3细胞系中获得的DQα和β cDNA克隆进行了测序和分析。DQα链序列与先前发表的DR4单倍型序列相同，但DQβ序列与从DQw3阳性TA10阴性细胞系获得的已发表的DR4-DQβ序列在8个氨基酸上不同，其中6个位于β1结构域。因此，TA10血清学决定簇位于DQβ链上。基于DQβ序列构建了TA10特异性寡核苷酸探针，并在一组TA10阳性和TA10阴性细胞系中证实了其特异性。在Southern印迹实验中观察到一条额外的条带，这可能表明存在基因转换的供体序列。
