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Updated: Jun 12, 2026
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Quantification of Monocyte Transmigration and Foam Cell Formation from Individuals with Chronic Inflammatory Conditions
Published on: October 17, 2017
Integrins and monocyte migration to the ischemic myocardium
Mryanda Sopel1, Irene Ma, Laura Gelinas
1Department of Surgery, Dalhousie University, Halifax, Nova Scotia, Canada.
Summary
Mononuclear cell migration increases significantly after myocardial infarction (MI), correlating with elevated MCP-1 mRNA. Integrin blockade partially inhibits this early cell migration in MI.
Area of Science:
- Cardiovascular Biology
- Immunology
- Cellular Biology
Background:
- Acute myocardial infarction (MI) triggers inflammatory responses.
- Understanding immune cell infiltration is crucial for cardiac repair.
- Mononuclear cell migration plays a key role in post-MI cardiac remodeling.
Purpose of the Study:
- To characterize mononuclear cell migration into the myocardium following acute myocardial infarction (MI).
- To investigate the role of monocyte chemoattractant protein-1 (MCP-1) in this process.
- To evaluate the involvement of alpha4 and beta2 integrins in mononuclear cell recruitment post-MI.
Main Methods:
- Male Lewis rats underwent induced myocardial infarction (MI) or sham surgery.
- In(111)-labeled mononuclear cells were administered at ischemia onset.
- Cell migration was quantified, and MCP-1 mRNA levels were measured.
- Monoclonal antibodies targeting alpha4 and beta2 integrins were used to assess migration inhibition.
Main Results:
- MI induced significant elevation in serum troponin and myocardial MCP-1 mRNA.
- A five-fold increase in labeled mononuclear cell migration was observed in the MI group.
- ED-1 positive mononuclear cells were detected in the ischemic myocardium within 24 hours.
- Alpha4 and beta2 integrin blockade partially inhibited mononuclear cell migration, with combined blockade showing 59% inhibition.
Conclusions:
- Mononuclear cell migration into the myocardium within 24 hours of MI is significant.
- This migration correlates with elevated MCP-1 mRNA levels.
- Early post-MI mononuclear cell migration is partially dependent on alpha4 and beta2 integrins.
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