Growth hormone enhances thymic function in HIV-1-infected adults

J Clin Invest. 2008 Mar;118(3):1085-98. doi: 10.1172/JCI32830.


Growth hormone (GH) is an underappreciated but important regulator of T cell development that can reverse age-related declines in thymopoiesis in rodents. Here, we report findings of a prospective randomized study examining the effects of GH on the immune system of HIV-1-infected adults. GH treatment was associated with increased thymic mass. In addition, GH treatment enhanced thymic output, as measured by both the frequency of T cell receptor rearrangement excision circles in circulating T cells and the numbers of circulating naive and total CD4(+) T cells. These findings provide compelling evidence that GH induces de novo T cell production and may, accordingly, facilitate CD4(+) T cell recovery in HIV-1-infected adults. Further, these randomized, prospective data have shown that thymic involution can be pharmacologically reversed in humans, suggesting that immune-based therapies could be used to enhance thymopoiesis in immunodeficient individuals.

Publication types

  • Randomized Controlled Trial
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acquired Immunodeficiency Syndrome / immunology
  • Acquired Immunodeficiency Syndrome / physiopathology*
  • Adult
  • Aged
  • CD4 Lymphocyte Count
  • Cross-Over Studies
  • Growth Hormone / adverse effects
  • Growth Hormone / therapeutic use*
  • HIV-1*
  • Humans
  • Insulin-Like Growth Factor I / analysis
  • Lymphopoiesis / drug effects
  • Middle Aged
  • Prospective Studies
  • Thymus Gland / drug effects*
  • Thymus Gland / physiopathology


  • Insulin-Like Growth Factor I
  • Growth Hormone