Skias D, Reder A T, Bania M B, Antel J P
Clin Immunol Immunopathol. 1985 May;35(2):191-9. doi: 10.1016/0090-1229(85)90065-0.
The mechanisms accounting for low levels of T-cell-dependent polyclonal IgG secretion in old and young human adults were compared. In elderly donors, in contrast to young donors, low levels of IgG secretion by unfractionated mononuclear cells (MNCs) did not correlate with functional suppressor activity of "panning"-enriched T8+ cells. Levels of IgG secretion by MNCs did not correlate either with proportions of T8+ or T4+ cells in the MNC population or with the functional helper activity of panning-enriched T4+ cells, in either old or young age groups. In young donors suppression mediated by either 2 or 5 X 10(4)T8+ cells of "low" IgG secretors (80.2 +/- 4.8 and 90.2 +/- 1.9%) was significantly greater than that induced by T8+ cells of "high" secretors (41.8 +/- 5.7 and 71.0 +/- 4.0%). Among elderly donors, suppression mediated by either 2 or 5 X 10(4)T8+ cells was reduced in both the low IgG secretion (31.9 +/- 5.3 and 52.3 +/- 7.0%) and high IgG secreting (14.9 +/- 7.2 and 46.8 +/- 5.7%) compared to the corresponding young donor subgroup. Levels of suppression mediated by 2 X 10(4)T8+ cells were suggestively lower in the high IgG secreting elderly subgroup compared to the low secreting subgroup (P less than 0.1). Our data suggest that decreased suppressor activity is a generalized occurrence in aging and that low polyclonal T-dependent MNC IgG secretion in the elderly, in contrast to young adults, cannot be attributed to high T-suppressor activity; nor does it usually reflect defective T-helper activity.
比较了老年和年轻成年人中T细胞依赖性多克隆IgG分泌水平较低的机制。与年轻供体相比，老年供体中未分级单核细胞（MNCs）的低水平IgG分泌与“淘选”富集的T8 +细胞的功能抑制活性无关。在老年或年轻年龄组中，MNCs的IgG分泌水平与MNC群体中T8 +或T4 +细胞的比例均无关，也与“淘选”富集的T4 +细胞的功能辅助活性无关。在年轻供体中，由2或5×10(4)个“低”IgG分泌者的T8 +细胞介导的抑制作用（80.2±4.8和90.2±1.9%）明显大于“高”分泌者的T8 +细胞诱导的抑制作用（41.8±5.7和71.0±4.0%）。在老年供体中，与相应的年轻供体亚组相比，由2或5×10(4)个T8 +细胞介导的抑制作用在低IgG分泌（31.9±5.3和52.3±7.0%）和高IgG分泌（14.9±7.2和46.8±5.7%）中均降低。与低分泌亚组相比，高IgG分泌老年亚组中由2×10(4)个T8 +细胞介导的抑制水平提示性降低（P小于0.1）。我们的数据表明，抑制活性降低是衰老过程中的普遍现象，与年轻成年人相比，老年人中低多克隆T细胞依赖性MNC IgG分泌不能归因于高T抑制活性；也通常不反映T辅助活性缺陷。
