Makinodan T, Albright J W, Good P I, Peter C P, Heidrick M L
Immunology. 1976 Dec;31(6):903-11.
Spleen cells from young (3-5 months) and old (22-27 months) mice were assessed in cultures, both in vivo and in vitro, for their anti-sheep RBC response separately and in mixtures. Pooled young spleens, pooled old spleens, and individual old spleens were analysed. The response of pure young spleen cells was always higher than that of pure old spleen cells (approximately 30 times). The responses of mixtures were either less than (i.e. reduced; frequency approximately 65%), comparable to (i.e. additive; frequency approximately 10%), or greater than (i.e. elevated; frequency approximately 30%) the sum of the responses given by equivalent numbers of pure young and pure old spleen cells. The reduced response was observed in mixtures containing cells from histologically normal old spleens, old spleens with tumours and old spleens with atrophic follicles. Additive and elevated responses were observed only in mixutres containing cells from histologically normal old spleens. The reduced response is explicable in terms of excessive numbers of suppressor cells in old spleens that can prevent young immunocompetent cells from responding maximally to the test antigen. The additive response can be accounted for by a reduction in number of immunocompetent cells in old spleens and/or a decrease in their functional efficiency. The elevated response can be explained by a reduction in number of at least one type of immunocompetent cell in old spleens that exists in excess in young spleens. These results indicate that there are several types of cellular changes responsible for the decrease in humoral immune activity in old mice. Pooling of old spleens, as was commonly done in the past, should therefore be discouraged. Not only might it selectively favour the expression of old spleens with an excess of supressor cells but it conceivably could result in an elevated response.
对年轻（3 - 5个月）和年老（22 - 27个月）小鼠的脾细胞进行了体内和体外培养评估，分别及混合培养时观察其对绵羊红细胞的反应。分析了合并的年轻脾细胞、合并的年老脾细胞以及单个年老脾细胞。纯年轻脾细胞的反应总是高于纯年老脾细胞（约30倍）。混合细胞的反应要么低于（即降低；频率约65%）、等同于（即相加；频率约10%），要么高于（即升高；频率约30%）等量纯年轻和纯年老脾细胞反应之和。在含有组织学正常的年老脾细胞、有肿瘤的年老脾细胞和有萎缩滤泡的年老脾细胞的混合物中观察到反应降低。仅在含有组织学正常的年老脾细胞的混合物中观察到相加和升高反应。反应降低可以用年老脾中抑制细胞数量过多来解释，这些抑制细胞可阻止年轻免疫活性细胞对测试抗原做出最大反应。相加反应可归因于年老脾中免疫活性细胞数量减少和/或其功能效率降低。升高反应可解释为年老脾中至少一种免疫活性细胞数量减少，而这种细胞在年轻脾中数量过多。这些结果表明，有几种细胞变化导致老年小鼠体液免疫活性下降。因此，应不鼓励像过去常见的那样合并年老脾细胞。这不仅可能会选择性地有利于具有过多抑制细胞的年老脾细胞的表达，而且可以想象可能会导致反应升高。
