Expression of molecular messages for angiogenesis by fibroblasts from aneurysmal abdominal aorta versus dermal...

The molecular messages which drive angiogenesis in the adventitia of an aneurysmal aorta are uncertain. The emergence of molecular phenotyping by cDNA expression arrays provides a simple and rapid method for a preliminary approach to the analysis of molecular messengers for neovascularization in cultured cells. In the present experiment, fibroblasts cultured from the aorta of a patient with abdominal aortic aneurysm (AAA) were compared with normal dermal fibroblasts, on an array that evaluates several mRNAs with known roles in angiogenesis.

RNA was isolated from fibroblasts and purified. Labelled cDNA probes were generated from a mixture of RNA and CDS primers. Atlas Array membranes (Clontech) were prehybridized by ExpressHyb buffer. The cDNA probes were then added to the membranes, which were exposed to Phospholmage Screen (Molecular Dynamics) and analysed by a dedicated computer program.

The most significantly upregulated mRNAs in AAA (by comparison to dermal fibroblasts) were: MCAF, MDNCF, EGR-1, VEGF, FGF-7, Mal protein, Mac Marcks, Transducin, Interleukin-9 receptor, and TNF.

VEGF and TNF were upregulated, as expected. However, the upregulation of monocyte chemotactic and activating factor (MCAF) and monocyte-derived neutrophil chemotactic factor (MDNCF) suggest that the fibroblast may be more significantly involved in driving the inflammatory response that leads to AAA than previously realized.