Ligand-activated T cell growth factor-induced proliferation: absorption of T cell growth factor by activated T cells.
Ligand-activated T cell growth factor-induced proliferation: absorption of T cell growth factor by activated T cells.
复制标题
配体激活的 T 细胞生长因子诱导的增殖：激活的 T 细胞吸收 T 细胞生长因子。
作者：
G. Bonnard;K. Yasaka;D. Jacobson
研究了体外培养的人T细胞(CTC)持续生长所需的T细胞生长因子(TCGF)在培养中的去向。TCGF活性在37℃下稳定7天，但在37℃下与生长活跃的CTC孵育3天后，检测不到TCGF活性。这种TCGF活性的丧失也发生得相当快，并在23℃下与2-5×10(7)CTC孵育0.3ml上清液的1小时内检测到。2×10(8)单核外周血白细胞对TCGF活性的去除无效，与来自B和T细胞系的相似数量的细胞孵育也没有影响。3日龄的刀豆蛋白A和植物血凝素母细胞对TCGF反应强烈，以致10(7)或2×10(7)细胞持续去除TCGF活性。这些实验提示激活的T细胞对TCGF的特异性吸收，并导致我们建立了一个配体激活的TCGF诱导T细胞增殖的模型：配体诱导T产生细胞产生TCGF，并向T反应细胞传递第一信号。这会导致T反应细胞上出现TCGF的受体。只有到那时，TCGF才会传递驱动T反应细胞增殖所必需的第二信号。
The fate in culture of the T cell growth factor (TCGF), which is required for continued growth of human cultured T cells (CTC) in vitro, was studied. TCGF activity was stable for 7 days at 37 degrees C. However, it was no longer detectable after incubation with actively growing CTC at 37 degrees C for 3 days. This loss of TCGF activity also occurred quite rapidly and was detectable within 1 hr of incubation of 0.3 ml supernatant with 2 to 5 x 10(7) CTC at 23 degrees C. 2 x 10(8) mononuclear peripheral blood leukocytes were not effective in removing TCGF activity, and incubation with similar numbers of cells from B and T cell lines had no effect. Three-day-old concanavalin A and phytohemagglutinin blasts were very reactive with TCGF, so that 10(7) or 2 x 10(7) cells consistently removed TCGF activity. These experiments suggested specific absorption of TCGF by activated T cells, and led us to develop a model of ligand-activated TCGF-induced proliferation of T cells: Ligands induce production of TCGF by T-producer cells and deliver a first signal to the T-responder cells. This causes a receptor for TCGF to appear on T-responder cells. Only then does TCGF deliver the obligatory second signal that is needed to drive the T-responder cells into proliferation.