Moulon C, Vollmer J, Weltzien H U
Max-Planck-Institut für Immunbiologie, Freiburg, Germany.
Eur J Immunol. 1995 Dec;25(12):3308-15. doi: 10.1002/eji.1830251216.
Metal ions such as nickel, cobalt, copper and palladium are known to be potent sensitizers in humans, but the antigenic determinants created by these metals as well as the mechanisms of recognition by specific T cell clones are still not elucidated. In this paper, nickel-specific T lymphocyte clones were isolated from four patients exhibiting contact dermatitis to this metal. A panel of 42 independent T cell clones was studied. They were shown to recognize nickel in the context of major histocompatibility complex (MHC) class II molecules and to belong to the CD4 subset. Using fixed autologous Epstein-Barr virus-transformed B cells as antigen-presenting cells (APC), we could distinguish two distinct groups of T cell clones on the basis of processing requirements: 40% of the T cell clones were strictly processing dependent, whereas the remaining 60% could proliferate in response to nickel even in the presence of glutaraldehyde-fixed APC. Furthermore, we present arguments indicating that individual Ni-specific T cell clones cross-react with some transition metals (e.g. Cu or Pd), but not with others (e.g. Co, Cr and Pt), presented by identical MHC class II molecules. These results thus provide an explanation for the multiple metal-reactivities observed in vivo in human patients: they indicate that for Cu and Pd, these co-reactivities in vivo might be due to cross-reactivity at the clonal level. Our findings also suggest that this is not the case for cobalt allergy, which might result from cosensitization of the patient to cobalt in addition to nickel.
已知镍、钴、铜和钯等金属离子是人类强效致敏剂，但这些金属产生的抗原决定簇以及特定T细胞克隆的识别机制仍未阐明。在本文中，从4名对这种金属表现出接触性皮炎的患者中分离出镍特异性T淋巴细胞克隆。研究了一组42个独立的T细胞克隆。结果表明，它们在主要组织相容性复合体（MHC）II类分子的背景下识别镍，且属于CD4亚群。使用固定的自体爱泼斯坦-巴尔病毒转化的B细胞作为抗原呈递细胞（APC），我们可以根据处理要求区分出两组不同的T细胞克隆：40%的T细胞克隆严格依赖处理，而其余60%即使在存在戊二醛固定的APC的情况下也能对镍产生增殖反应。此外，我们提出的证据表明，单个镍特异性T细胞克隆与某些过渡金属（如铜或钯）发生交叉反应，但不与由相同MHC II类分子呈递的其他金属（如钴、铬和铂）发生交叉反应。因此，这些结果为在人类患者体内观察到的多种金属反应性提供了解释：它们表明，对于铜和钯，体内的这些共同反应性可能是由于克隆水平的交叉反应。我们的研究结果还表明，钴过敏并非如此，钴过敏可能是患者除了对镍过敏外还对钴产生了共致敏作用。
