Cellular microparticles: what are they bad or good for?

Area of Science:

• Cell biology
• Hemostasis
• Pathophysiology

Background:

• Microparticles are cell membrane fragments previously considered inert debris.
• Emerging evidence shows microparticles actively interact with other cells, possessing pathophysiologic potential.
• They are implicated in both adverse cellular responses and maintaining homeostasis.

Purpose of the Study:

• To explore the dual role of microparticles in cellular interactions and homeostasis.
• To highlight the pathophysiologic significance of microparticles beyond cell death markers.
• To establish the hemostasis laboratory as a critical tool for assessing microparticle function.

Main Methods:

• Analysis of microparticle release from stimulated or apoptotic cells.
• Investigation of microparticle interactions with neighboring and remote cells.
• Assessment of procoagulant properties and phosphatidylserine exposure.
• Utilizing hemostasis laboratory assays for in vivo significance.

Main Results:

• Microparticles can trigger adverse cellular responses, amplifying pathological processes.
• They play a role in maintaining homeostasis by reflecting cell stimulation, proliferation, and death.
• Platelet-derived microparticles exhibit procoagulant properties, potentially leading to thrombosis when excessive.
• Vesiculation, involving phosphatidylserine migration, is central to microparticle formation and function.

Conclusions:

• Microparticles are biologically active and significantly influence cellular communication and organismal homeostasis.
• Their procoagulant properties are crucial, particularly for platelet-derived microparticles, with implications for thrombosis.
• Hemostasis laboratory assessments are vital for evaluating the in vivo relevance of microparticles.