Lorré K, Fransen L, Ceuppens J L
Department of Medicine and Pathophysiology, University of Leuven, Belgium.
Eur Cytokine Netw. 1992 May-Jun;3(3):321-30.
We examined requirements for TNF-alpha production by purified human blood T cells, completely depleted of monocyte-accessory cells, under different conditions of stimulation. Activation of T cells with immobilized anti-CD3 induced the appearance of mRNA for TNF-alpha and of functionally active TNF-alpha in the culture supernatant. Anti-CD3-induced TNF-alpha production could be inhibited by blocking the IL-2R with a combination of anti-Tac and Mik beta 1 (mAbs against the p55 and p75 chain of the IL-2R respectively) thus indicating an essential role of IL-2 in TNF-alpha induction. When purified T cells were activated with a combination of two anti-CD2 mAbs (9-1 and 9.6), additional signals (rIL-2 or rIL-1 beta or anti-CD28) were required for TNF-alpha mRNA production and protein secretion. rIL-1 beta supported anti-CD2-induced TNF-alpha production indirectly through an IL-2-dependent pathway. These same helper signals also enhanced TNF-alpha production by anti-CD3-stimulated T cells. IL-4, IL-6, GM-CSF and IFN-gamma had no effect on TNF-alpha production by T cells activated via either pathway. Addition of rIL-1 beta alone, rIL-2 alone or endotoxins to resting human T cells did not induce detectable amounts of TNF-alpha. Both helper/inducer CD4(+) and suppressor/cytotoxic CD8(+) subsets of T cells were shown to produce TNF-alpha upon stimulation. We conclude that CD3 or CD2 triggering are not sufficient for TNF-alpha production by T cells, but that the latter is dependent (apparently at the transcriptional level) on the interaction of IL-2 with its functionally active cell surface receptors. We could further demonstrate that TNF-alpha production was completely blocked by cyclosporin A. The inhibitory effect of this agent on TNF-alpha production was also observed in the presence of rIL-2, thus excluding an indirect effect through inhibition of IL-2 production.
我们研究了在不同刺激条件下，完全去除单核细胞辅助细胞的纯化人血T细胞产生肿瘤坏死因子-α（TNF-α）的条件。用固定化抗CD3激活T细胞可诱导培养上清液中出现TNF-α的mRNA以及功能活性TNF-α。抗CD3诱导的TNF-α产生可通过用抗Tac和Mikβ1（分别针对IL-2R的p55和p75链的单克隆抗体）组合阻断IL-2R来抑制，这表明IL-2在TNF-α诱导中起重要作用。当用两种抗CD2单克隆抗体（9-1和9.6）组合激活纯化的T细胞时，TNF-αmRNA产生和蛋白质分泌需要额外的信号（重组人白细胞介素-2（rIL-2）或重组人白细胞介素-1β（rIL-1β）或抗CD28）。rIL-1β通过IL-2依赖性途径间接支持抗CD2诱导的TNF-α产生。这些相同的辅助信号也增强了抗CD3刺激的T细胞产生TNF-α的能力。白细胞介素-4（IL-4）、白细胞介素-6（IL-6）、粒细胞-巨噬细胞集落刺激因子（GM-CSF）和干扰素-γ（IFN-γ）对通过任何一种途径激活的T细胞产生TNF-α均无影响。单独向静息人T细胞中添加rIL-1β、单独添加rIL-2或内毒素均未诱导出可检测量的TNF-α。辅助/诱导性CD4(+)和抑制/细胞毒性CD8(+)T细胞亚群在受到刺激时均显示可产生TNF-α。我们得出结论，CD3或CD2触发不足以使T细胞产生TNF-α，但后者（显然在转录水平）依赖于IL-2与其功能活性细胞表面受体的相互作用。我们还可以进一步证明环孢素A可完全阻断TNF-α的产生。在存在rIL-2的情况下也观察到了该药物对TNF-α产生的抑制作用，从而排除了通过抑制IL-2产生的间接作用。
