Monocyte Imaging
Mikael Pittet, PhD

Live-time imaging of human monocytes transmigrating acutely inflamed human umbilical vein endothelial cells under in vitro flow conditions.

  1. Endothelial cell lateral junctions are outlined by immunofluorescence staining of platelet-endothelial cell adhesion molecule (PECAM)-1 (red staining).

  2. Phase contrast image shows actively transmigrating monocytes (arrows) and freshly arrested monocyte (asterisk).

  3. When the two images are overlaid it is clearly demonstrated that monocytes migrate at the lateral junctions via a paracellular route traversing the endothelial adherens junctions.

Leukocytes, metastatic tumor cells and progenitor cells must cross the endothelial lining of the blood vessels to incorporate into new tissue sites. Understanding the route of transmigration and the adhesion molecules that mediate these transmigration events will provide us with possible therapeutic targets to reduce inflammation, prevent metastasis or promote tissue regeneration following injury.