Guillet J G, Lai M Z, Briner T J, Buus S, Sette A, Grey H M, Smith J A, Gefter M L
Science. 1987 Feb 20;235(4791):865-70. doi: 10.1126/science.2433769.
The ability of immunodominant peptides derived from several antigen systems to compete with each other for T cell activation was studied. Only peptides restricted by a given transplantation antigen are mutually competitive. There is a correlation between haplotype restriction, ability to bind to the appropriate transplantation antigen, and ability to inhibit activation of other T cells restricted by the same transplantation antigen. An exception was noted in that a peptide derived from an antigen, bacteriophage lambda cI repressor, binds to the I-Ed molecule in a specific way, yet is not I-Ed-restricted. Comparison of the sequence of the repressor peptide with that of other peptides able to bind to (and be restricted by) I-Ed and a polymorphic region of the I-Ed molecule itself revealed a significant degree of homology. Thus, peptides restricted by a given class II molecule appear to be homologous to a portion of the class II molecule itself. The repressor-derived peptide is identical at several polymorphic residues at this site, and this may account for the failure of I-Ed to act as a restriction element. Comparison of antigenic peptide sequences with transplantation antigen sequences suggests a model that provides a basis for explaining self, nonself discrimination as well as alloreactivity.
研究了源自几种抗原系统的免疫显性肽相互竞争T细胞活化的能力。只有受给定移植抗原限制的肽才会相互竞争。单倍型限制、与适当移植抗原结合的能力以及抑制受同一移植抗原限制的其他T细胞活化的能力之间存在相关性。不过发现了一个例外情况，即源自抗原噬菌体λcI阻遏物的一种肽以特定方式与I-Ed分子结合，但不受I-Ed限制。将阻遏肽的序列与其他能够结合（并受其限制）I-Ed的肽以及I-Ed分子本身的一个多态性区域的序列进行比较，发现了显著程度的同源性。因此，受给定II类分子限制的肽似乎与II类分子本身的一部分同源。阻遏物衍生肽在该位点的几个多态性残基处是相同的，这可能解释了I-Ed未能作为限制元件的原因。将抗原肽序列与移植抗原序列进行比较，提出了一个模型，该模型为解释自身、非自身识别以及同种异体反应性提供了基础。
