Yanagida T, Kato T, Igarashi O, Inoue T, Nariuchi H
Department of Allergology, University of Tokyo, Japan.
J Immunol. 1994 May 15;152(10):4919-28.
In these experiments, effects of IL-12 on the proliferation and IL-2R expression of Th1 and Th2 clones were studied. Although neither Th1 nor Th2 clones proliferated on an Ag stimulation with B cell APC, Th1 clones but not Th2 clones, exhibited IL-2-dependent proliferation in the presence of IL-12 in response to the Ag stimulation. The IL-2R alpha-chain was also shown to be induced on Th1 clones when they were stimulated with B cell APC in the presence of IL-12. Effects of IL-12 on these T cell functions were indicated to be exerted in concert with IL-2, although IL-12 did not enhance IL-2 production of Th1 clones. Cytokines produced by Th1 clones such as IFN-gamma and TNF-alpha were indicated not to be involved in induction of the IL-2R alpha-chain expression or proliferation. IL-12 also induced proliferation and IL-2R alpha-chain expression of Th1 clone stimulated with anti-CD3 in the absence of APC, indicating that IL-12 exerted the effect on Th1 cells directly and other costimulator signal from APC is not required for the function of IL-12. In contrast to IL-12, IL-1 induced proliferation and IL-2R alpha-chain expression of Th2 clones stimulated with Ag on B cell APC. The failure of IL-12 in the induction of IL-2R alpha-chain expression on Th2 clone seemed not to be caused by the IL-4 produced by the clone. These results suggest that IL-12 plays an important role in IL-2R alpha-chain expression and proliferation of Th1 clones, but not Th2 clones, as a second signal.
在这些实验中，研究了白细胞介素-12（IL-12）对Th1和Th2克隆的增殖及IL-2受体表达的影响。尽管在B细胞抗原呈递细胞（APC）存在下，Th1和Th2克隆在抗原刺激时均不增殖，但在抗原刺激时，Th1克隆而非Th2克隆在IL-12存在的情况下表现出IL-2依赖性增殖。当Th1克隆在IL-12存在下被B细胞APC刺激时，也显示出IL-2Rα链被诱导。尽管IL-12不会增强Th1克隆的IL-2产生，但表明IL-12对这些T细胞功能的影响是与IL-2协同发挥作用的。Th1克隆产生的细胞因子如干扰素-γ（IFN-γ）和肿瘤坏死因子-α（TNF-α）未参与IL-2Rα链表达或增殖的诱导。IL-12还在无APC的情况下诱导了用抗CD3刺激的Th1克隆的增殖和IL-2Rα链表达，表明IL-12直接对Th1细胞发挥作用，且IL-12的功能不需要来自APC的其他共刺激信号。与IL-12相反，IL-1诱导了在B细胞APC上用抗原刺激的Th2克隆的增殖和IL-2Rα链表达。IL-12未能诱导Th2克隆上IL-2Rα链表达似乎不是由该克隆产生的IL-4所致。这些结果表明，IL-12作为第二信号在Th1克隆而非Th2克隆的IL-2Rα链表达和增殖中起重要作用。
