Yu D T, Winchester R J, Fu S M, Gibofsky A, Ko H S, Kunkel H G
J Exp Med. 1980 Jan 1;151(1):91-100. doi: 10.1084/jem.151.1.91.
The Ia antigens, usually expressed primarily on B lymphocytes, are found on a small percentage of normal peripheral blood T cells (average 2.6% by fluorescence and 10.8% by rosette assay). Elevated levels up to 40% by both assays were observed in a high proportion of patients with rheumatoid arthritis. Increases also were found in patients with systemic lupus erythematosus and various types of infections. The increases were evident with a specific heteroantiserum, a hybridoma reagent, and DR specific alloantisera. Normal levels were present in multiple sclerosis and an assortment of metabolic and other disorders. A rise in similarly positive T cells occurred in normal individuals after immunization with tetanus toxoid or PPD. The cells primarily involved in all of these instances were small lymphocytes, which stained relatively weakly with the fluorescent reagents and were readily distinguishable from T-cell blasts. They were found to be enriched in isolated T gamma fractions but were also found in other T cells. The accumulated evidence indicated that these cells represent an expansion of one or more subsets of T cells found in normal individuals, and that their level in the peripheral blood may serve as an index of immunological stimulation.
Ia抗原通常主要在B淋巴细胞上表达，在一小部分正常外周血T细胞中也可发现（通过荧光检测平均为2.6%，通过玫瑰花结试验为10.8%）。在高比例的类风湿性关节炎患者中，两种检测方法均显示Ia抗原水平升高至40%。系统性红斑狼疮患者和各类感染患者中也发现Ia抗原水平升高。使用特异性异种抗血清、杂交瘤试剂和DR特异性同种抗血清时，这种升高现象很明显。多发性硬化症患者以及一系列代谢紊乱和其他疾病患者中Ia抗原水平正常。正常个体在接种破伤风类毒素或结核菌素纯蛋白衍生物后，同样呈阳性的T细胞会增多。所有这些情况中主要涉及的细胞是小淋巴细胞，它们用荧光试剂染色相对较弱，很容易与T细胞母细胞区分开来。发现它们在分离出的Tγ亚群中富集，但在其他T细胞中也有发现。累积的证据表明，这些细胞代表正常个体中发现的一个或多个T细胞亚群的扩增，并且它们在外周血中的水平可能作为免疫刺激的一个指标。
