Miyawaki T, Uehara T, Nibu R, Tsuji T, Yachie A, Yonehara S, Taniguchi N
Department of Pediatrics, School of Medicine, Kanazawa University, Ishikawa, Japan.
J Immunol. 1992 Dec 1;149(11):3753-8.
The Fas Ag is a newly defined cell-surface molecule that may mediate apoptosis. The antibody against Fas Ag can induce the apoptotic cell death in cell lines expressing this Ag. PBL subpopulations at various ages were here examined for Fas expression by two-or three-color flow-cytometric analyses using anti-Fas mAb. It was found that Fas Ag was appreciably detected on a proportion of T and B cells, whereas its expression was absent for NK cells. For CD4+ and CD8+ T cells, Fas Ag was expressed preferentially on CD45RO+ (memory or previously activated) populations, but not on CD45RO- naive ones. TCR-gamma/delta+ T cells, especially their CD45RO+ subsets, also expressed Fas Ag. Expectably, neonatal T cell subpopulations, most of which had the naive (CD45RO-) phenotype, expressed little Fas Ag. Fas-expressing B cells dominated in surface(s) IgD- populations, but neonatal B cells as well as adult sIgD+ B cells had little Fas Ag. The Fas Ag was inducible after in vitro mitogenic stimulation of naive T and B cells from neonatal blood. These observations suggested that expression of Fas Ag on T and B cells in the peripheral blood might reflect their in vivo Ag-activated status. In contrast to Fas-expressing cultured cell lines, however, viability of in vitro stimulated T and B cells as well as freshly isolated CD45RO+ T cells was not significantly changed after the treatment with anti-Fas mAb, indicating that additional cellular conditions to Fas expression might be required for anti-Fas-induced cell death.
Fas抗原是一种新定义的可能介导细胞凋亡的细胞表面分子。抗Fas抗原抗体可诱导表达该抗原的细胞系发生凋亡性细胞死亡。本文利用抗Fas单克隆抗体，通过双色或三色流式细胞术分析检测了不同年龄的外周血淋巴细胞亚群中Fas的表达情况。结果发现，在一定比例的T细胞和B细胞上可明显检测到Fas抗原，而自然杀伤细胞上则未检测到其表达。对于CD4⁺和CD8⁺ T细胞，Fas抗原优先表达于CD45RO⁺（记忆性或先前活化的）细胞群体，而在CD45RO⁻幼稚细胞上不表达。TCR-γ/δ⁺ T细胞，尤其是其CD45RO⁺亚群，也表达Fas抗原。不出所料，大多数具有幼稚（CD45RO⁻）表型的新生儿T细胞亚群几乎不表达Fas抗原。表达Fas的B细胞在表面IgD⁻细胞群体中占主导，但新生儿B细胞以及成人表面IgD⁺ B细胞几乎不表达Fas抗原。体外有丝分裂原刺激新生儿血液中的幼稚T细胞和B细胞后，Fas抗原可被诱导表达。这些观察结果提示，外周血T细胞和B细胞上Fas抗原的表达可能反映了它们在体内的抗原活化状态。然而，与表达Fas的培养细胞系不同，用抗Fas单克隆抗体处理后，体外刺激的T细胞和B细胞以及新鲜分离的CD45RO⁺ T细胞的活力并未显著改变，这表明抗Fas诱导的细胞死亡可能还需要Fas表达以外的其他细胞条件。
