First evidence of in vivo pro-angiogenic activity of cerebrospinal fluid samples from multiple sclerosis patients

Increased vascular density and endothelial cell proliferation have been demonstrated in multiple sclerosis (MS) white matter, as well as an elevated vascular endothelial growth factor expression was detected in reactive astrocytes of both active and inactive chronic demyelinated lesions and in sera of MS patients during clinical relapses. In this study, we have investigated the angiogenic activity of cerebrospinal fluid (CSF) samples from MS patients with different stages of disease by means of the chick embryo chorioallantoic membrane (CAM), a well-known assay to study angiogenesis in vivo. Results have shown that CSF samples from MS patients induced a significant (p < 0.05) angiogenic response in CAM in comparison with CSF from neurological controls. The vessel density was higher (p < 0.0001) in secondary (23.60 ± 1.14) and primary (23.50 ± 1.87) progressive patients in comparison with relapsing MS (17.25 ± 1.75) and clinically isolated syndrome suggestive of MS (13.00 ± 1.79), and a significant correlation (r = 0.611, p = 0.005) was found between the angiogenic response and disability level. The results of this preliminary report demonstrate for the first time an angiogenic activity in vivo of CSF samples from MS patients and confirm the importance of angiogenesis as a key event in MS pathogenesis and progression.