Ou D, Mitchell L A, Décarie D, Tingle A J, Nepom G T
Department of Paediatrics, Faculty of Medicine, University of British Columbia, Vancouver, Canada.
Hum Immunol. 1998 Mar;59(3):149-57. doi: 10.1016/s0198-8859(98)00006-8.
Two T cell clones derived from different donors with HLA-DRB10403 or DRB10901 phenotype recognize a rubella capsid peptide, C(265-273) in the context of several different HLA-DR molecules in addition to DRB10403 and DRB10901. All DR molecules restricting the T-cell clones have in common residues, R or Q at position beta 70, R at position beta 71, and E at position beta 74 in pocket '4' of the DR peptide binding groove, suggesting that a DR subregion structure or supertype, "Q/RRE" underlies the promiscuous T-cell recognition of this peptide. Single amino acid substituted analogs of peptide C(263-275) at anchor position 4 for natural residue R were tested for their ability to induce clonal T-cell cytotoxic responses. The results indicated that a positively charged residue, R or K, was required for T-cell recognition, suggesting a possible mechanism of electrostatic interactions between the negatively charged residue E at position beta 74 of these DR molecules and the positively charged residue at anchor position 4 of the peptide in T-cell recognition.
来自不同供体的两个具有HLA - DRB10403或DRB10901表型的T细胞克隆，除了DRB10403和DRB10901外，还能在几种不同的HLA - DR分子背景下识别风疹衣壳肽C(265 - 273)。所有限制这些T细胞克隆的DR分子在DR肽结合槽的“4”号口袋中，β70位有共同残基R或Q、β71位有R、β74位有E，这表明一种DR亚区域结构或超型“Q/RRE”是该肽杂乱T细胞识别的基础。对肽C(263 - 275)在锚定位置4处天然残基R的单氨基酸取代类似物诱导克隆性T细胞细胞毒性反应的能力进行了测试。结果表明，T细胞识别需要一个带正电荷的残基R或K，这表明在T细胞识别中，这些DR分子β74位带负电荷的残基E与肽锚定位置4处带正电荷的残基之间可能存在静电相互作用机制。
