Cantrell D A, Davies A A, Crumpton M J
Proc Natl Acad Sci U S A. 1985 Dec;82(23):8158-62. doi: 10.1073/pnas.82.23.8158.
As judged by indirect immunofluorescence, phorbol 12,13-dibutyrate and 1-oleoyl-2-acetylglycerol induced a rapid, concentration-dependent decrease of about 50% in the surface expression of the T3 antigen on human T lymphoblasts, and of T3 and the T-cell antigen receptor on HPB-ALL cells. Direct binding experiments using 125I-labeled antibody indicated that the reduction in T3 expression corresponded to a decrease in the number of antigen molecules rather than a change in their affinity. Biochemical analyses revealed that phorbol dibutyrate induced a rapid, prominent phosphorylation of the T3 Mr 26,000 gamma chain and to a lesser extent of the Mr 21,000 delta chain. No phosphorylation of the T3 epsilon chain or of the alpha and beta subunits of the T-cell antigen receptor was detected. The data suggest that protein kinase C induces a phosphorylation of the T3 gamma and delta chains that may lead to the down-regulation of the T3/T-cell antigen receptor complex.
通过间接免疫荧光法判断，佛波醇12,13 - 二丁酸酯和1 - 油酰基 - 2 - 乙酰甘油可使人T淋巴母细胞表面T3抗原的表达迅速、浓度依赖性地降低约50%，并使HPB - ALL细胞表面的T3和T细胞抗原受体表达降低。使用125I标记抗体的直接结合实验表明，T3表达的降低对应于抗原分子数量的减少，而非其亲和力的改变。生化分析显示，佛波醇二丁酸酯可使T3的26,000 Mrγ链迅速、显著磷酸化，对21,000 Mrδ链的磷酸化程度较低。未检测到T3ε链或T细胞抗原受体的α和β亚基发生磷酸化。数据表明，蛋白激酶C可诱导T3γ链和δ链磷酸化，这可能导致T3/T细胞抗原受体复合物的下调。
