# Mechanisms That Prevent Vascular Leakage During Leukocyte Extravasation

## TL;DR

This paper explains how the body prevents blood vessel leakage when immune cells move into tissues during inflammation.

## Contribution

The paper summarizes mechanisms that uncouple immune cell migration from vascular leakage and their potential for therapeutic targeting.

## Key findings

- Leukocyte transmigration and vascular leakage are regulated independently.
- Several mechanisms limit vascular leakage during immune cell movement.
- These mechanisms have clinical relevance for treating inflammatory diseases.

## Abstract

Inflammation is the response of the immune system against harmful stimuli in tissues. Leukocyte extravasation or TransEndothelial Migration (TEM) is a crucial step during inflammation, in which leukocytes migrate over the endothelial barrier toward the damaged tissue.

Historically, it was believed that leukocyte TEM directly causes excessive vascular leakage, resulting in tissue edema. However, it is now clear that leukocyte TEM and vascular leakage are uncoupled events with different spatiotemporal regulation. Moreover, several mechanisms have been identified that prevent vascular leakage during leukocyte TEM.

Here we summarize the different mechanisms that are responsible for limiting the leakage during the transmigration event and explore their clinical relevance in developing targeted therapeutics for controlling vascular leakage in inflammatory diseases.