Spontaneous activation of circulating granulocytes in patients with acute myocardial and cerebral diseases

Area of Science:

• Cardiovascular Research
• Hematology
• Immunology

Background:

• Circulating granulocytes can become activated, contributing to microvascular injury during shock and ischemia.
• Spontaneous granulocyte activation, marked by pseudopod formation (actin polymerization), increases the risk of microvascular entrapment.

Purpose of the Study:

• To investigate differences in in vitro granulocyte pseudopod formation between healthy volunteers and patients with acute cardiovascular illnesses.
• To assess the role of plasma factors in granulocyte activation in acute myocardial infarction.

Main Methods:

• Collected blood samples from 25 healthy volunteers, 12 acute myocardial infarction (AMI) patients, and 12 acute cerebral infarction (ACI) patients.
• Utilized high-resolution light microscopy to quantify spontaneous pseudopod formation in granulocytes over several hours.
• Incubated healthy granulocytes in AMI plasma and serially diluted AMI plasma to evaluate plasma factor effects.

Main Results:

• Granulocyte pseudopod formation in healthy controls remained below 10% for 3 hours, rising to ~50% at 12 hours.
• AMI patients exhibited a rapid increase in granulocyte activation, reaching 90% within 4-5 hours, unlike ACI patients who showed no significant difference from controls.
• Incubation of healthy granulocytes in AMI plasma induced activation similar to AMI granulocytes in their own plasma, with activation decreasing upon plasma dilution.

Conclusions:

• Acute myocardial infarction patients possess plasma factors that accelerate granulocyte activation compared to healthy individuals.
• Elevated granulocyte activation in AMI may play a critical role in the pathophysiology of cardiovascular events.
• The findings suggest a potential diagnostic or therapeutic target related to granulocyte activation in AMI.