Reynolds D S, Boom W H, Abbas A K
J Immunol. 1987 Aug 1;139(3):767-73.
Helper/inducer T cell clones specific for protein antigens and class II MHC determinants consist of two nonoverlapping subsets. One (called Th1) secretes IL 2 and IFN-gamma and the other (Th2) produces BSF1 upon stimulation with antigen or polyclonal activators. By using hapten-binding normal B cells and the B lymphoma line WEHI-279 as assays for B cell helper (maturation) factors, we have shown that Th2 clone supernatants (SN) induce differentiation to antibody secretion, whereas Th1 SN do not. The failure of Th1 SN to activate B cells is due to inhibitory effects of IFN-gamma, because it can be reversed by a neutralizing monoclonal antibody specific for IFN-gamma. Thus, in the presence of this antibody, even Th1 SN stimulate B cell maturation maximally. Conversely, recombinant IFN-gamma inhibits proliferation and differentiation of B cells induced by active Th2 SN. These results demonstrate that IFN-gamma is a potent inhibitor of B lymphocyte activation and can be distinguished from growth and maturation-inducing helper factors that are produced by both subsets of helper T cells.
针对蛋白质抗原和Ⅱ类主要组织相容性复合体（MHC）决定簇的辅助/诱导性T细胞克隆由两个不重叠的亚群组成。其中一个亚群（称为Th1）分泌白细胞介素2（IL 2）和γ干扰素（IFN-γ），另一个亚群（Th2）在受到抗原或多克隆激活剂刺激后产生B细胞刺激因子1（BSF1）。通过使用结合半抗原的正常B细胞和B淋巴瘤细胞系WEHI-279作为B细胞辅助（成熟）因子的检测方法，我们发现Th2克隆的培养上清液（SN）可诱导B细胞分化为分泌抗体的细胞，而Th1克隆的SN则不能。Th1克隆的SN无法激活B细胞是由于IFN-γ的抑制作用，因为用针对IFN-γ的中和性单克隆抗体可逆转这种抑制作用。因此，在存在这种抗体的情况下，即使是Th1克隆的SN也能最大程度地刺激B细胞成熟。相反，重组IFN-γ可抑制活性Th2克隆的SN诱导B细胞的增殖和分化。这些结果表明，IFN-γ是B淋巴细胞激活的有效抑制剂，并且可与由辅助性T细胞的两个亚群产生的生长和成熟诱导性辅助因子区分开来。
