Falk W, Von Högen I, Krammer P H
Institute for Immunology and Genetics, German Cancer Research Center, Heidelberg.
Lymphokine Res. 1989 Fall;8(3):263-8.
The cytokine interleukin-1 plays an important role in the induction of IL-2 secretion and IL-2 receptor expression. The events that follow binding of IL-1 to its receptor are not known. We found that in a purified T cell population (comprising the Lyt2- and L3T4- T cells) IL-1 in the absence of antigen or mitogen induced strong proliferation and de novo expression of IL-2R light chain mRNA. This was accompanied by high affinity IL-2 binding. Production of IL-2 or IL-2 mRNA was not detected under these conditions. As a model system for IL-1 action two EL4 subclones were isolated. EL4 5D3 responded to IL-1 by augmentation of PMA induced IL-2 secretion and IL-2R expression. EL4D6/76 bound IL-1 with the same affinity but did not respond. We found that this line was unable to internalize surface bound IL-1. The finding suggests that in T cells internalization of IL-1 is required for its activity.
细胞因子白细胞介素-1在诱导白细胞介素-2分泌和白细胞介素-2受体表达中起重要作用。白细胞介素-1与其受体结合后发生的事件尚不清楚。我们发现，在纯化的T细胞群体（包括Lyt2-和L3T4-T细胞）中，在无抗原或有丝分裂原的情况下，白细胞介素-1可诱导强烈增殖和白细胞介素-2受体轻链mRNA的从头表达。这伴随着高亲和力的白细胞介素-2结合。在这些条件下未检测到白细胞介素-2或白细胞介素-2 mRNA的产生。作为白细胞介素-1作用的模型系统，分离出两个EL4亚克隆。EL4 5D3通过增强佛波酯诱导的白细胞介素-2分泌和白细胞介素-2受体表达来响应白细胞介素-1。EL4D6/76以相同的亲和力结合白细胞介素-1，但无反应。我们发现该细胞系无法内化表面结合的白细胞介素-1。这一发现表明，在T细胞中，白细胞介素-1的内化是其发挥活性所必需的。
