Reverse transendothelial cell migration in inflammation: to help or to hinder?

Area of Science:

• Immunology
• Cell Biology
• Vascular Biology

Background:

• The endothelium forms a barrier between blood and tissues, regulating immune cell trafficking.
• Transendothelial migration is crucial for immune cells to reach infection sites.
• The exit of immune cells from tissues back into circulation is less understood.

Purpose of the Study:

• To review evidence supporting reverse transendothelial migration (RTM) and reverse interstitial migration.
• To highlight recent findings on the mechanisms of RTM.
• To discuss the biological significance of leukocyte retrograde migration.

Main Methods:

• Literature review of studies on immune cell migration across endothelium.
• Analysis of recent research detailing mechanisms of RTM.
• Postulation of the biological roles of retrograde migration.

Main Results:

• Evidence supports leukocytes migrating out of tissues and back into circulation.
• Recent studies are beginning to elucidate the molecular mechanisms of RTM.
• Retrograde migration may influence inflammation and pathology.

Conclusions:

• Reverse transendothelial migration is a validated biological process.
• Understanding RTM mechanisms is critical for controlling inflammation.
• Retrograde migration may impact systemic inflammation and disease progression.