It is becoming more and more clear that angiogenic mechanisms leading to structural formation of blood vessels are very complex, and understanding them depends on studies performed by means of a wide methodological spectrum ranging from molecular biological techniques to morphological analyses (1 -4 ). To study the maturation and stabilization of newly formed blood vessels, processes that include many successive steps, the following aspects and methods are important:
| 1. | Examination of structural components of the vascular wall indicating vascular stabilization by means of light and electron microscopy. |
| 2. | Immunohistochemical and immune electron microscopic studies on tissues and cells with improved methods for precise localization of angiogenic factors during vascular maturation. |
| 3. | Chemotactic assay on human endothelial cells using the Boyden chamber to test their migration response to angiogenesis activators and inhibitors. |
| 4. | Three-dimensional endothelial tube formation assay on collagen gel: an in vitro angiogenesis model. |
| 5. | Chorioallantoic membrane (CAM) assay as an easy in vivo angiogenesis assay. |
