Odaka C, Kizaki H, Tadakuma T
Department of Microbiology, School of Medicine, Keio University, Tokyo, Japan.
J Immunol. 1990 Mar 15;144(6):2096-101.
Activation of Ag-specific T cell hybridomas with a high density of immobilized anti-CD3 antibody resulted in not only secretion of IL-2 but also cell death of up to 60 to 80% in selected hybridomas after 14 h. Similar results were obtained with V beta 8+ T cell hybridomas stimulated with cross-linked F23.1 antibody. In these activated hybridomas, we found that DNA was fragmented into 180- to 200-bp multiples. DNA fragmentation was not observed when T cells were maintained after killing with anti-Thy-1 plus C or with heat treatment at 45 degrees C, nor when T cells were incubated with fixed anti-CD4 antibody. Furthermore, fragmentation was detectable at 6 h after incubation when almost all of the cells were still viable as evaluated by trypan blue dye exclusion test. Cell death was prevented by addition of EGTA, cycloheximide, actinomycin D, and zinc, suggesting that the induction of cell death requires Ca2+ influx, newly synthesized protein(s), and involvement of endonuclease.
用高密度固定化抗CD3抗体激活抗原特异性T细胞杂交瘤，不仅会导致IL-2的分泌，而且在14小时后，部分杂交瘤细胞死亡率高达60%至80%。用交联的F23.1抗体刺激Vβ8 + T细胞杂交瘤也得到了类似结果。在这些活化的杂交瘤中，我们发现DNA被片段化为180至200碱基对的倍数。在用抗Thy-1加补体C处理后杀伤的T细胞中，或在45℃热处理后的T细胞中，以及在用固定的抗CD4抗体孵育的T细胞中，均未观察到DNA片段化。此外，通过台盼蓝拒染试验评估，当几乎所有细胞仍存活时，孵育6小时后即可检测到片段化。添加EGTA、环己酰亚胺、放线菌素D和锌可防止细胞死亡，这表明细胞死亡的诱导需要Ca2 +内流、新合成的蛋白质以及核酸内切酶的参与。
