Chang M P, Utsuyama M, Hirokawa K, Makinodan T
Geriatric Research, Education and Clinical Center, VA Medical Center, West Los Angeles, CA 90073.
Cell Immunol. 1988 Aug;115(1):1-12. doi: 10.1016/0008-8749(88)90157-8.
Previously, we and others have found that the ability to produce interleukin-1 (IL-1) and interleukin-2 (IL-2) declines with age in mice. The purpose of this study was to determine the influence of age on the capacity of mice to produce interleukin-3 (IL-3). Splenic cells (5 X 10(6)/ml) from young (3-4 months) and old (24-32 months) C57BL/6 mice were first assessed for their IL-3-producing capacities in response to varying doses of concanavalin A (Con A; 2-20 micrograms/ml) in a time-dependent manner. The results showed that the production of IL-3 by both young and old C57BL/6 mice was maximal on Days 3 and 4 in response to 20 micrograms/ml of Con A, and that of IL-2 was minimal (activity was less than 0.1 unit) on Day 4. Consequently, Day 4, was selected to assess the effect of age on IL-3 production by splenic cells. The results showed a twofold reduction in IL-3 production with age (P less than 0.05). Young-old splenic cell mixture experiments at ratios of 1:0, 3:1, 1:1, 1:3, and 0:1 indicated that the decrease in IL-3 production with age was not due to an increase in suppressor cell activity. Experiments based on mixtures of nylon wool-enriched splenic T-cell and adherent cells and on anti-MAC-1 plus complement-treated spleen cells indicated that (a) adherent cells are not required for T-cell production of IL-3, unlike IL-2 production, and (b) the decrease in IL-3 production with age is due solely to alteration in IL-3-producing T cells. Finally, a strong correlation was demonstrated between the production of IL-2 and IL-3 by spleen cells of individual young and old mice (r = 0.92, P less than 0.01). That production of both IL-2 and IL-3 is affected in a similar manner by age would suggest that a single class of helper T cells may be responsible for production of both lymphokines.
此前，我们和其他人发现，小鼠体内白细胞介素-1（IL-1）和白细胞介素-2（IL-2）的产生能力会随着年龄增长而下降。本研究的目的是确定年龄对小鼠产生白细胞介素-3（IL-3）能力的影响。首先，以时间依赖的方式评估来自年轻（3 - 4个月）和年老（24 - 32个月）C57BL/6小鼠的脾细胞（5×10⁶/ml）在不同剂量刀豆蛋白A（Con A；2 - 20微克/ml）刺激下产生IL-3的能力。结果显示，年轻和年老的C57BL/6小鼠在第3天和第4天对20微克/ml的Con A刺激产生的IL-3最多，而IL-2在第4天产生最少（活性小于0.1单位）。因此，选择第4天来评估年龄对脾细胞产生IL-3的影响。结果显示，随着年龄增长，IL-3的产生减少了两倍（P小于0.05）。年轻与年老脾细胞以1:0、3:1、1:1、1:3和0:1的比例混合实验表明，IL-3产生随年龄的下降并非由于抑制细胞活性增加。基于尼龙毛富集的脾T细胞和贴壁细胞混合物以及抗MAC-1加补体处理的脾细胞的实验表明：（a）与IL-2产生不同，T细胞产生IL-3不需要贴壁细胞；（b）IL-3产生随年龄的下降完全是由于产生IL-3的T细胞发生了改变。最后，在个体年轻和年老小鼠的脾细胞产生IL-2和IL-3之间显示出强烈的相关性（r = 0.92，P小于0.01）。IL-2和IL-3的产生都以类似方式受到年龄影响，这表明可能是单一类别的辅助性T细胞负责产生这两种淋巴因子。
