Cooper H M, Corradin G, Paterson Y
Department of Immunology, Research Institute of Scripps Clinic, La Jolla, California 92037.
J Exp Med. 1988 Sep 1;168(3):1127-43. doi: 10.1084/jem.168.3.1127.
In these studies, we have shown that the heme moiety of cyt c is a dominant T cell epitope that induces a large proliferative response in lymph node T cells derived from SJL and B10.A mice when presented on either unfixed or fixed syngeneic APCs. Not only is this vigorous response observed for cyt c-primed T cell populations but also for populations obtained from naive SJL or B10.A mice. The reactivity to the heme moiety falls under strict MHC restriction, in that it is present only in murine strains bearing either the I-Ak or I-As molecule and can be blocked by antibodies specific for these class II molecules. Therefore, these findings require that the current models describing the nature of T cell epitopes be extended to include nonpeptide molecules. Furthermore, as the heme moiety is ubiquitous throughout the organism, although sequestered within proteins, the existence of heme-reactive T cell populations in unprimed animals provides another example of the existence of self-reactive T cell clones.
在这些研究中，我们已经表明，细胞色素c的血红素部分是一个主要的T细胞表位，当呈递在未固定或固定的同基因抗原呈递细胞（APC）上时，它能在源自SJL和B10.A小鼠的淋巴结T细胞中诱导强烈的增殖反应。这种强烈反应不仅在细胞色素c致敏的T细胞群体中观察到，在源自未致敏的SJL或B10.A小鼠的群体中也能观察到。对血红素部分的反应性受到严格的主要组织相容性复合体（MHC）限制，因为它仅存在于携带I-Ak或I-As分子的小鼠品系中，并且可以被针对这些II类分子的特异性抗体阻断。因此，这些发现要求当前描述T细胞表位性质的模型进行扩展，以纳入非肽分子。此外，由于血红素部分在整个生物体中普遍存在，尽管它被隔离在蛋白质内部，但在未致敏动物中存在对血红素反应的T细胞群体，这为自身反应性T细胞克隆的存在提供了另一个例子。
