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PR-39, a porcine antimicrobial peptide, inhibits apoptosis: involvement of caspase-3

Balaji Ramanathan1, Hua Wu, Christopher R Ross

  • 1Department of Anatomy and Physiology, College of Veterinary Medicine, Kansas State University, Coles Hall 228, 1600 Denison Avenue, Manhattan, KS 66506-5602, USA.

Developmental and Comparative Immunology
|September 13, 2003
PubMed

Insights

The antimicrobial peptide PR-39 from pigs prevents macrophage cell death. This finding suggests PR-39 plays a role in regulating inflammatory responses beyond just killing bacteria.

Area of Science:

  • Immunology
  • Cell Biology
  • Biochemistry

Background:

  • Porcine antimicrobial peptide (PR-39) exhibits diverse biological activities.
  • Antimicrobial peptides are crucial in innate immunity.
  • Macrophage apoptosis plays a significant role in regulating inflammatory processes.

Purpose of the Study:

  • To investigate the effect of PR-39 on macrophage viability.
  • To determine if PR-39 modulates apoptosis in macrophages under various stress conditions.

Main Methods:

  • Macrophage cell cultures were subjected to nutrient depletion, LPS stimulation, and camptothecin treatment.
  • Apoptosis was assessed by measuring annexin-V binding and caspase-3 activity.
  • The effect of PR-39 on these apoptosis markers was quantified.

Main Results:

  • PR-39 significantly inhibited apoptosis in macrophages induced by nutrient depletion, LPS, or camptothecin.
  • PR-39 treatment led to reduced annexin-V binding, indicating less externalized phosphatidylserine.
  • A decrease in caspase-3 activity was observed in PR-39 treated macrophages.

Conclusions:

  • PR-39 possesses potent antiapoptotic properties in macrophages.
  • This peptide modulates inflammatory cell viability by regulating apoptosis.
  • PR-39 may have a dual role in inflammation: antimicrobial and immunomodulatory.

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