Watson J, Gillis S, Marbrook J, Mochizuki D, Smith K A
J Exp Med. 1979 Oct 1;150(4):849-61. doi: 10.1084/jem.150.4.849.
Murine spleen cells activated by concanavalin A (Con A) in culture produce a class of lymphokine molecules which possess biological activity in a number of lymphocyte response assays. Lymphokines with a mol wt of 30,000, as estimated from gel filtration studies, can be resolved into two components which differ by charge, with isoelectric point (pI) values of 4.3 and 4.9, respectively. Both components stimulate (a) the growth of established T-cell lines in culture, (b) the proliferation of thymocytes in the presence of Con A under culture conditions where Con A alone is nonmitogenic, (c) the induction of antibody responses to heterologous erythrocyte antigens in athymic (nude) spleen cultures, (d) the generation of cytotoxic T lymphocytes (CTL) in thymocyte cultures, and (e) the generation of CTL in nude spleen cultures. In each of these culture systems we suggest that the assays are detecting a single class of lymphokine which acts directly on activated T cells. Nonactivated T cells must be stimulated by either antigen or mitogen before becoming responsive to lymphokine, but do not require antigen or mitogen for continued growth with lymphokine. The two molecular species, separable by isoelectric focusing are referred to as the T-cell growth factor (TCGF). A lymphokine, similar in size (30,000 daltons) to TCGF but heterogeneous in charge (pI 3.0--4.0), stimulates immune responses to erythrocyte antigens in T-cell-depleted spleen cultures but has no stimulatory activity in the other lymphocyte assay systems described. The data have been interpreted as showing the two molecular forms of murine TCGF (pI 4.3 and 4.9) are responsible for many of the lymphokine activities described elsewhere as thymocyte mitogenic factor, nonspecific T-cell-replacing factor and killer helper factor or costimulator. The other lymphokine, separable from TCGF by charge, appears to have true T-cell-replacing activity.
在培养中由伴刀豆球蛋白A（Con A）激活的小鼠脾细胞产生一类淋巴因子分子，这些分子在许多淋巴细胞反应试验中具有生物活性。根据凝胶过滤研究估计，分子量为30,000的淋巴因子可分解为两个电荷不同的组分，其等电点（pI）值分别为4.3和4.9。这两个组分均能刺激：（a）培养中已建立的T细胞系的生长；（b）在Con A单独无促有丝分裂作用的培养条件下，Con A存在时胸腺细胞的增殖；（c）无胸腺（裸）脾培养物中对异源红细胞抗原的抗体反应的诱导；（d）胸腺细胞培养物中细胞毒性T淋巴细胞（CTL）的产生；以及（e）裸脾培养物中CTL的产生。在这些培养系统中的每一个中，我们认为这些试验检测的是一类直接作用于活化T细胞的单一淋巴因子。未活化的T细胞在对淋巴因子产生反应之前必须由抗原或有丝分裂原刺激，但在与淋巴因子一起持续生长时不需要抗原或有丝分裂原。通过等电聚焦可分离的这两种分子形式被称为T细胞生长因子（TCGF）。一种与TCGF大小相似（30,000道尔顿）但电荷异质（pI 3.0 - 4.0）的淋巴因子，在T细胞耗竭的脾培养物中刺激对红细胞抗原的免疫反应，但在所述的其他淋巴细胞试验系统中无刺激活性。这些数据被解释为表明小鼠TCGF的两种分子形式（pI 4.3和4.9）负责许多在其他地方被描述为胸腺细胞促有丝分裂因子、非特异性T细胞替代因子和杀伤辅助因子或共刺激因子的淋巴因子活性。另一种通过电荷与TCGF可分离的淋巴因子似乎具有真正的T细胞替代活性。
