Nualláin E M, Davis W C, Fisher A D, Monaghan M L
Department of Large Animal Clinical Studies, Faculty of Veterinary Medicine, University College Dublin, Ireland.
Vet Res Commun. 1997 Jan;21(1):19-28. doi: 10.1023/b:verc.0000009697.61013.6f.
Stimulation of T-lymphocytes with mitogens or antigens results in the production of the cytokine interleukin-2, which exerts its physiological effect by interacting with a specific IL-2 receptor on the cell surface. The alpha-chain of this receptor is induced and expressed on the cell surface after lymphocyte activation. Following continuous antigen stimulation, a smaller soluble form of this alpha-subunit (sIL-2R-alpha) is shed from the membrane of activated cells. This study describes a sandwich ELISA for bovine sIL-2R-alpha that was developed using monoclonal antibodies specific for bovine IL-2R-alpha (CD 25). The feasibility of using sIL-2R-alpha released by activated T-lymphocytes as an in vitro marker of cell-mediated immunity (CMI) in cattle is demonstrated. Calves were immunized with the foreign protein keyhole limpet haemocyanin (KLH) and the development of CMI was followed using sIL-2R-alpha release, IFN-gamma production and lymphocyte proliferation assay. The results showed that the release of sIL-2R-alpha by previously sensitized cells following stimulation with antigen is likely to be a useful marker of CMI in infectious diseases, and in the study of T cell antigens and/or novel vaccines. Using appropriate detection systems, the measurement of sIL-2R-alpha may also prove to be a useful marker of CMI in other species.
用丝裂原或抗原刺激T淋巴细胞会导致细胞因子白细胞介素-2的产生，白细胞介素-2通过与细胞表面的特异性白细胞介素-2受体相互作用发挥其生理作用。该受体的α链在淋巴细胞活化后在细胞表面被诱导并表达。在持续的抗原刺激后，这种α亚基的较小可溶性形式（sIL-2R-α）从活化细胞的膜上脱落。本研究描述了一种针对牛sIL-2R-α的夹心ELISA，它是使用对牛IL-2R-α（CD 25）特异的单克隆抗体开发的。证明了使用活化的T淋巴细胞释放的sIL-2R-α作为牛细胞介导免疫（CMI）的体外标志物的可行性。用外来蛋白钥孔戚血蓝蛋白（KLH）免疫犊牛，并使用sIL-2R-α释放、γ干扰素产生和淋巴细胞增殖试验跟踪CMI的发展。结果表明，先前致敏的细胞在抗原刺激后释放sIL-2R-α可能是传染病中CMI的有用标志物，也可用于T细胞抗原和/或新型疫苗的研究。使用适当的检测系统，sIL-2R-α的测量在其他物种中也可能被证明是CMI的有用标志物。
