Jacoby D R, Oldstone M B
J Immunol. 1983 Oct;131(4):1765-70.
Lymphocytes taken from the cord blood of newborns have active suppressor activity. Using in vitro PWM-stimulated cocultures, unfractionated T cells from newborns potently suppressed the expected immunoglobulin G (IgG) synthesis of their mothers' peripheral blood lymphocytes (PBL). Using positive and negative selection techniques, we characterized the active suppressor cell as expressing the OKT4+T8- phenotype. This cord blood lymphocyte subset suppressed maternal IgG synthesis after depletion of maternal suppressor cells, implicating the ability of newborn T cells to suppress directly rather than by inducing adult suppressor activity. Sublethal amounts (1500 rad) of gamma-irradiation fully abrogated the suppressor activity of cord blood T lymphocytes. Radioresistant cord T cells provided T cell help. Irradiation of cord OKT4+ and OKT8+ populations and their subsequent culture with maternal B cells determined that helper activity was a radioresistant subpopulation of the OKT4+ subset. These results indicate significant differences in the functional properties of T cell subsets from adults and newborns. Population studies determined that cord blood lymphocytes had a greater proportion of OKT4+ cells and lower proportion of OKT8+ cells than PBL from unrelated adults. The mothers tested had similar proportions of OKT4+ cells as their babies, and these levels are significantly higher than those of unrelated adults.
取自新生儿脐带血的淋巴细胞具有活跃的抑制活性。利用体外经PWM刺激的共培养体系，新生儿未分离的T细胞能有效抑制其母亲外周血淋巴细胞（PBL）预期的免疫球蛋白G（IgG）合成。运用阳性和阴性选择技术，我们将活跃的抑制细胞鉴定为表达OKT4 + T8 - 表型。在去除母亲的抑制细胞后，这种脐带血淋巴细胞亚群仍能抑制母亲的IgG合成，这表明新生儿T细胞具有直接抑制的能力，而非通过诱导成人抑制活性来实现。亚致死剂量（1500拉德）的γ射线照射完全消除了脐带血T淋巴细胞的抑制活性。具有辐射抗性的脐带T细胞提供T细胞辅助功能。对脐带血OKT4 + 和OKT8 + 细胞群进行照射，然后与母亲的B细胞共同培养，结果表明辅助活性是OKT4 + 亚群中的一个具有辐射抗性的亚群。这些结果表明成人和新生儿T细胞亚群的功能特性存在显著差异。群体研究确定，与无关成人的PBL相比，脐带血淋巴细胞中OKT4 + 细胞的比例更高，OKT8 + 细胞的比例更低。接受检测的母亲的OKT4 + 细胞比例与其婴儿相似，且这些水平显著高于无关成人。
