Interleukin-16 stimulates the expression and production of pro-inflammatory cytokines by human monocytes

Immunology. 2000 May;100(1):63-9. doi: 10.1046/j.1365-2567.2000.00997.x.


Interleukin-16 (IL-16) acts as a chemoattractant for CD4+ cells, as a modulator of T-cell activation, and plays a key role in asthma. This report describes the cytokine-inducing effects of IL-16 on total peripheral blood mononuclear cells (PBMC) and PBMC subpopulations. While CD4+ T lymphocytes did not secrete cytokines in response to rhIL-16, CD14+ CD4+ monocytes and maturing macrophages secrete IL-1beta, IL-6, IL-15 and tumour necrosis factor-alpha (TNF-alpha) upon rhIL-16 stimulation. The mRNA species for these four cytokines were detected as early as 4 hr post-stimulation, with protein being secreted by 24 hr. Secretion of IL-1beta and IL-6 by total PBMC was dose dependent, with maximal secretion being observed using 50 ng/ml rhIL-16. However, for IL-15 or TNF-alpha maximal secretion by total PBMC occurred with all concentrations between 5 ng/ml to 500 ng/ml rhIL-16. Purified monocytes/macrophages secreted maximal concentrations of all four cytokines in the presence of 500 ng/ml rhIL-16, except for monocytes where maximal secretion of IL-15 was, interestingly, observed with only 50 ng/ml rhIL-16. The use of higher concentrations of rhIL-16 (1000 ng/ml) inhibited secretion of all four cytokines. While these IL-16-induced cytokines are likely to be involved in the immune system's response to antigen, the data suggest that IL-16 may play a key role in initiating and/or sustaining an inflammatory response.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • CD4 Antigens / analysis
  • CD4-Positive T-Lymphocytes / immunology
  • Cell Culture Techniques
  • Cell Differentiation / immunology
  • Cytokines / biosynthesis
  • Cytokines / genetics
  • Cytokines / metabolism*
  • Humans
  • Interleukin-16 / immunology*
  • Lipopolysaccharide Receptors / analysis
  • Macrophages / immunology
  • Monocytes / immunology*
  • RNA, Messenger / genetics
  • Reverse Transcriptase Polymerase Chain Reaction


  • CD4 Antigens
  • Cytokines
  • Interleukin-16
  • Lipopolysaccharide Receptors
  • RNA, Messenger