[Ability of human monocytes to activate in atherosclerosis]

Insights

Individual immune response characteristics, not cholesterol, dictate monocyte activation. This study reveals significant patient variations in macrophage activation, impacting immune responses in atherosclerosis.

Area of Science:

  • Immunology
  • Cardiovascular Science
  • Cell Biology

Background:

  • Monocytes play a key role in immune responses and are implicated in atherosclerosis.
  • Intima-media thickness (IMT) and atherosclerotic plaques indicate cardiovascular risk.
  • Macrophage activation markers include TNF-α and CCL18.

Purpose of the Study:

  • To investigate individual differences in monocyte activation capacity.
  • To explore the relationship between intracellular cholesterol and monocyte activation.
  • To determine if atherogenic lipoproteins influence monocyte activation.

Main Methods:

  • Isolation of monocytes from patients with varying carotid IMT and atherosclerotic plaque status.
  • Measurement of TNF-α and CCL18 cytokine/chemokine concentrations in culture medium.
  • In vitro culture of monocytes with modified low-density lipoprotein to induce cholesterol accumulation.

Main Results:

  • Significant individual variations in TNF-α and CCL18 levels were observed across all patient groups.
  • An inverse correlation was found between intracellular cholesterol levels and monocyte activation.
  • Induced intracellular cholesterol accumulation did not affect cytokine secretion or gene expression.

Conclusions:

  • Individual differences in monocyte activation capacity are not solely determined by intracellular cholesterol accumulation from atherogenic lipoproteins.
  • The findings suggest that inherent individual characteristics of the immune response are crucial in modulating monocyte activation.
  • Understanding these individual variations may offer new insights into personalized approaches for managing atherosclerosis.