Moderate physical activity associated with a higher naïve/memory T-cell ratio in healthy old individuals: potential role of IL15.

Journal Article (Journal Article)

INTRODUCTION: ageing is accompanied by impairments in immune responses due to remodelling of the immune system (immunesenescence). Additionally, a decline in habitual physical activity has been reported in older adults. We have recently published that specific features of immunesenescence, such as thymic involution and naïve/memory T-cell ratio, are prevented by maintenance of a high level of physical activity. This study compares immune ageing between sedentary and physically active older adults. METHODS: a cross-sectional study recruited 211 healthy older adults (60-79 years) and assessed their physical activity levels using an actigraph. We compared T- and B-cell immune parameters between relatively sedentary (n = 25) taking 2,000-4,500 steps/day and more physically active older adults (n = 25) taking 10,500-15,000 steps/day. RESULTS: we found a higher frequency of naïve CD4 (P = 0.01) and CD8 (P = 0.02) and a lower frequency of memory CD4 cells (P = 0.01) and CD8 (P = 0.04) T cells in the physically active group compared with the sedentary group. Elevated serum IL7 (P = 0.03) and IL15 (P = 0.003), cytokines that play an essential role in T-cell survival, were seen in the physically active group. Interestingly, a positive association was observed between IL15 levels and peripheral CD4 naïve T-cell frequency (P = 0.023). DISCUSSION: we conclude that a moderate level of physical activity may be required to give a very broad suppression of immune ageing, though 10,500-15,000 steps/day has a beneficial effect on the naïve T-cell pool.

Full Text

Duke Authors

Cited Authors

  • Bartlett, DB; Duggal, NA

Published Date

  • April 27, 2020

Published In

Volume / Issue

  • 49 / 3

Start / End Page

  • 368 - 373

PubMed ID

  • 32221610

Electronic International Standard Serial Number (EISSN)

  • 1468-2834

Digital Object Identifier (DOI)

  • 10.1093/ageing/afaa035


  • eng

Conference Location

  • England