Chemotactic Migration of Endothelial Cells Towards VEGF-A₁₆₅.

In vitro assays of endothelial cell migration have led to critical insights into the mechanisms of angiogenesis. The transwell assay, or modified Boyden chamber assay was developed to investigate chemotaxis, which corresponds to the directional migration of cells in response to a chemoattractant gradient. It is a robust and easy-to-use assay that does not require expensive equipment. In the modified Boyden chamber assay, two compartments are separated with a porous membrane through which cells can migrate. The lower compartment contains the chemoattractant, creating a gradient by diffusing into the upper chamber containing the cells. The cells will migrate through the membrane and remain on the lower side of the membrane, where they can finally be fixed and counted.