Correlation between T lymphocyte subsets in peripheral blood lymphocytes and 2-year all-cause mortality in an apparently healthy elderly Chinese cohort

摘要

Background Few data have been acquired on the predictive value of age-related T-lymphocyte subsets among older individuals.The present study has determined the distribution of T-cell phenotypes and their correlation to 2-year mortality in a cohort of Chinese male seniors.Methods A total of 101 asymptomatic elderly individuals with laboratory homeostasis were enrolled at baseline.Three age subgroups were categorized as young (65-74 years old),middle (75-84 years old ),and old (≥85 years) for age-related comparison.T-cell subsets in peripheral blood were measured by multi-colored flow cytometry.Results At baseline,there was a mild negative correlation by age for total lymphocytes and CD3+ T-cells.The frequency of CD28 and CD95 demonstrated a "curved" rather than linear tendency by age.At 2-year follow-up,little change of T-cell distribution was found among those who remained alive (as survivors) comparing the data at baseline to the 2-year time point.Immune risk phenotypes were distinctly demonstrated between survivors and non-survivors.Conclusions Since few studies have studied on the distribution of T-lymphocyte subsets in an elderly Chinese population,our results have not only provided reference values of T-subsets for aged Chinese men,but confirmed the immune risk phenotypes among elderly Chinese.The inappropriate age-dependent trajectory of CD28-/CD8+ and CD95-/CD8+ by age,which suggested 85 might be an inflexion point of age during T-cell ageing,warrants further exploration of the underlying mechanisms of T-cell ageing.