Procoagulant activity of activated monocytes

Area of Science:

• Immunology
• Hematology

Background:

• Monocytes play a crucial role in hemostasis and thrombosis.
• Tissue factor is a key initiator of the coagulation cascade.

Purpose of the Study:

• To investigate the effect of endotoxin stimulation on monocyte tissue factor activity.
• To compare tissue factor activity in monocytes isolated by different methods.

Main Methods:

• Monocyte-enriched mononuclear blood cells were isolated using Ficoll-Urovision density gradient centrifugation.
• Tissue factor-like activity was measured in monocytes with and without endotoxin stimulation.
• Monocytes were also isolated by plastic adherence for activity assessment.

Main Results:

• Endotoxin-stimulated monocytes exhibited significantly higher tissue factor activity compared to unstimulated monocytes.
• Monocytes isolated by plastic adherence showed tissue factor activity comparable to endotoxin-stimulated monocytes.
• This suggests that plastic adherence may induce or reveal high tissue factor activity.

Conclusions:

• Monocyte tissue factor activity is markedly enhanced by endotoxin stimulation.
• Plastic adherence is an effective method for isolating monocytes with high intrinsic tissue factor activity.
• These findings have implications for understanding monocyte procoagulant potential in various physiological and pathological conditions.