Saltzman E M, Thom R R, Casnellie J E
Department of Pharmacology and Cancer Center, University of Rochester Medical Center, New York 14642.
J Biol Chem. 1988 May 25;263(15):6956-9.
The ability of the T lymphocyte growth factor interleukin 2 (IL-2) to activate a tyrosine protein kinase in vivo was assessed by using antibodies to phosphotyrosine in conjunction with immunoblots. Treatment of the murine IL-2-dependent cytotoxic T cell line CTLL-2 with IL-2 resulted in an increase in tyrosine phosphorylation of several proteins of molecular weights ranging from 38,000 to 120,000. The tyrosine phosphorylation in the various proteins increased in a concomitant fashion and reached a maximum level within 15 min. The concentration of IL-2 required for inducing this phosphorylation was similar to that required for stimulating [3H]thymidine uptake, indicating that the increase in tyrosine phosphorylation correlated with the ability of IL-2 to stimulate the proliferation of the CTLL-2 cells. IL-2 was also found to induce the phosphorylation of proteins on tyrosine residues in short term cultures of human T lymphocytes. These results suggest that IL-2, like other polypeptide growth factors, acts by stimulating the activity of a tyrosine protein kinase.
通过使用抗磷酸酪氨酸抗体结合免疫印迹法，评估了T淋巴细胞生长因子白细胞介素2（IL-2）在体内激活酪氨酸蛋白激酶的能力。用IL-2处理小鼠IL-2依赖性细胞毒性T细胞系CTLL-2，导致几种分子量在38,000至120,000之间的蛋白质的酪氨酸磷酸化增加。各种蛋白质中的酪氨酸磷酸化以伴随的方式增加，并在15分钟内达到最高水平。诱导这种磷酸化所需的IL-2浓度与刺激[3H]胸苷摄取所需的浓度相似，表明酪氨酸磷酸化的增加与IL-2刺激CTLL-2细胞增殖的能力相关。还发现IL-2可在人T淋巴细胞的短期培养中诱导蛋白质酪氨酸残基的磷酸化。这些结果表明，IL-2与其他多肽生长因子一样，通过刺激酪氨酸蛋白激酶的活性起作用。
