Functional subsets within clonally expanded CD8+ memory T cells in elderly humans

Winston D. Chamberlain, Michael T. Falta, Brian L. Kotzin

Research output: Contribution to journalArticlepeer-review

43 Scopus citations


With advancing age, healthy humans frequently demonstrate large clonal expansions of CD8+ T cells in the peripheral blood, which persist for long periods of time and appear to be maintained as a population of memory cells. We studied nine large T cell clones in five elderly individuals. We noted that in most cases the expanded clones were dominated by cells that did not express CD28, a pivotal molecule in T cell activation, and these clones proliferated poorly in culture. However, nearly all of the clonal expansions had CD28+ fractions and some of these cells appeared to lose CD28 gene expression with stimulation in culture. CD28+ cells demonstrated greater proliferation in both bulk and limiting dilution cultures compared to CD28- cells bearing the same TCR, whereas CD28- cells showed increased perforin expression. Together, these data suggest that loss of CD28 expression marks functional differentiation to cytotoxic memory cells within these clonal expansions and likely within CD8+ memory populations in general. (C) 2000 Academic Press.

Original languageEnglish (US)
Pages (from-to)160-172
Number of pages13
JournalClinical Immunology
Issue number3
StatePublished - Mar 2000
Externally publishedYes


  • Memory cells, CD8 T lymphocytes, CD28 expression
  • T cell clonal expansions
  • T lymphocytes

ASJC Scopus subject areas

  • Immunology and Allergy
  • Immunology


Dive into the research topics of 'Functional subsets within clonally expanded CD8+ memory T cells in elderly humans'. Together they form a unique fingerprint.

Cite this