THE STEM CELL - THYMUS AXIS

这项研究的目的是为了更全面地了解 胸腺在原胸腺细胞分化为 胎儿、青年和老年小鼠的T淋巴细胞。 在体外和 将采用体内技术。 胚胎卵黄囊干细胞 将通过以下方法分离肝脏、年轻成人骨髓和老年骨髓： 利用它们通过化学吸引迁移到介质的倾向 由新生胸腺或胸腺上皮（T-E）细胞调节。 细胞 由培养的干细胞形成的集落， 将检测胸腺上皮细胞是否存在T淋巴细胞 抗原标志物、T淋巴细胞功能和 分化 为了研究免疫衰老的程度 胸腺随着年龄的增长而退化， 皮下注射在葡聚糖珠上培养的T-E细胞。 的效果 T-E细胞产生的因子对T淋巴细胞的恢复有影响 通过检查脾细胞的IL-2产生来测量功能， 对Con A的反应和细胞毒性。 将检测骨髓细胞 对于它们在体外对胸腺上清液的化学吸引和在体内对胸腺上清液的化学吸引， 迁移到受辐射宿主的胸腺。 注射液中的淋巴细胞 将检查研究中心的胸腺细胞标志物。 无胸腺小鼠将 类似地处理并测试T淋巴细胞的产生。 通过这个 研究表明，T-E细胞产生的因子产生 将建立T淋巴细胞功能。 这项基础研究将是 可用于开发合理的治疗方法， 免疫系统的畸形、故障或老化。

The aim of this proposed research is to more completely understand the role played by the thymus in the differentiation of prothymocytes to T-lymphocytes in fetal, young adult and aged mice. Both in vitro and in vivo techniques will be employed. Stem cells from the yolk sac, fetal liver, young adult bone marrow and aged bone marrow will be isolated by utilizing their propensity to migrate by chemoattraction to media conditioned by newborn thymus or thymic epithelial (T-E) cells. Cells from colonies formed by cultured stem cells stimulated by factors produced by thymic epithelial cells, will be tested for the presence of T-lymphocyte antigenic markers, T-lymphocyte function, and morphologic signs of differentiation. To study the extent to which immunosenescence is a result of the thymus degenerating with age, aged mice will be injected subcutaneously with T-E cells cultured on dextran beads. The effect which factors produced by the T-E cells have on the restoration of T-lymphocyte function will be measured by examining spleen cells for IL-2 production, response to Con A and for cytotoxicity. Bone marrow cells will be tested for their in vitro chemoattraction to thymic supernatant and in vivo migration to the thymus of irradiated hosts. Lymphocytes in the injection site will be examined for thymocyte markers. Athymic mice will be similarly treated and tested for generation of T-lymphocytes. Through this study, the capacity of factors produced by T-E cells to generate T-lymphocyte function will be established. This basic research will be useful in developing rational therapy for disease processes resulting from malformation, malfunction, or aging of the immune system.