Multiparameter evaluation of human thymic function: Interpretations and caveats

Jeffrey M. Harris, Mette D. Hazenberg, Jean François Poulin, Dana Higuera-Alhino, Diane Schmidt, Michael Gotway, Joseph M. McCune

Research output: Contribution to journalArticle

61 Scopus citations

Abstract

After the provision of highly active antiretroviral therapy (HAART), the level of circulating CD4+ T cells increases in many adults infected with the human immunodeficiency virus, type 1 (HIV). To study factors involved in immune reconstitution, we have measured thymic abundance by CT scans, circulating naive-phenotype CD4+ T cells by flow cytometry, and T cell receptor (TCR) rearrangement excision circles (TRECs) by quantitative PCR in 40 virologically suppressed, HIV-infected adults and 33 age-matched, HIV-uninfected controls. In HIV-uninfected subjects, naive T cell numbers, thymic abundance, and the frequency of circulating naive CD4+ T cells bearing TRECs decreased with age, as expected. When corrected for this relationship with age, naive T cell numbers correlated significantly with naive T cell TREC frequencies. Virologically suppressed HIV-infected subjects had higher TREC frequencies, and subjects over the age of 39 were more likely to have abundant thymus compared to age-matched, HIV-uninfected adults. Nevertheless, all HIV-infected subjects had reduced absolute numbers of naive T cells, irrespective of thymic size, age, or TREC frequencies. These data illustrate the complex relationship between these measures of thymic size and function and underscore the need to develop more definitive measures of thymic function in the future.

Original languageEnglish (US)
Pages (from-to)138-146
Number of pages9
JournalClinical Immunology
Volume115
Issue number2
DOIs
StatePublished - May 1 2005

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Keywords

  • AIDS
  • Chronic HIV infection
  • Human
  • Immune reconstitution
  • Naive T lymphocyte
  • Recent thymic emigrants
  • TREC
  • Thymic function
  • Thymus

ASJC Scopus subject areas

  • Immunology and Allergy
  • Immunology

Cite this

Harris, J. M., Hazenberg, M. D., Poulin, J. F., Higuera-Alhino, D., Schmidt, D., Gotway, M., & McCune, J. M. (2005). Multiparameter evaluation of human thymic function: Interpretations and caveats. Clinical Immunology, 115(2), 138-146. https://doi.org/10.1016/j.clim.2004.12.008