Cytokine expression in advanced human atherosclerotic plaques: dominance of pro-inflammatory (Th1) and macrophage-stimulating cytokines

Atherosclerosis. 1999 Jul;145(1):33-43. doi: 10.1016/s0021-9150(99)00011-8.


The atherosclerotic lesion contains large numbers of macrophages and T lymphocytes. This suggests that a cellular immune response may take place in the lesion, and oxidized lipoproteins, heat shock proteins, and micro-organisms have been implied as candidate antigens. However, the effector mechanisms elicited by this response have been largely unclear. We have therefore analyzed endarterectomy specimens by immunohistochemistry and reverse transcription-PCR to detect immune cytokines produced by immunocompetent cells of the advanced human plaque. The pro-inflammatory T cell cytokines, interleukin-2 and interferon-7, were found in a large proportion of plaques (IL-2 in 50% and interferon-gamma in 30% of plaques by immunohistochemistry and mRNA for both cytokines in 70% of plaques by PCR). In contrast, interleukin-4 and interleukin-5 were rarely observed (both cytokines in 10% of plaques by immunohistochemistry, mRNA for interleukin-4 in 10% and for interleukin-5 in 40% by PCR). This demonstrates the presence of a predominantly pro-inflammatory, Th1-type T cell response in atherosclerosis. This conclusion was further supported by the expression of the pro-inflammatory cytokine, interleukin-1 by plaque macrophages and endothelial cells. In addition, the chemokine interleukin-8 and the macrophage differentiation-stimulating cytokine, granulocyte-monocyte colony stimulating factor, were observed in plaque tissues, suggesting that the micro-environment promotes monocyte recruitment and macrophage differentiation. Occasional eosinophils and B cells were, however observed, which is compatible with a microheterogeneity within the lesion. Finally, the anti-inflammatory and fibrogenic cytokines, transforming growth factor-beta1-3 and its carrier protein, latent TGF-beta binding protein, were found in large amounts in all plaques. Together, these results show that a pro-inflammatory, Thl type cellular immune response takes place in the atherosclerotic plaque. The balance between pro-inflammatory and anti-inflammatory cytokines may be decisive for the progression of the lesion.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arteriosclerosis / metabolism*
  • Arteriosclerosis / pathology
  • Carrier Proteins / analysis
  • Cytokines / analysis*
  • Humans
  • Immunohistochemistry
  • Inflammation Mediators / analysis*
  • Interferon-gamma / analysis
  • Interleukins / analysis
  • Macrophages / metabolism
  • Macrophages / pathology
  • Macrophages / physiology
  • Polymerase Chain Reaction
  • Th1 Cells / metabolism
  • Th1 Cells / pathology
  • Transforming Growth Factor beta / analysis
  • Tumor Necrosis Factor-alpha / analysis


  • Carrier Proteins
  • Cytokines
  • Inflammation Mediators
  • Interleukins
  • Transforming Growth Factor beta
  • Tumor Necrosis Factor-alpha
  • Interferon-gamma