THE ROLE OF PDGF-BB ON THE DEVELOPMENT OF THE COLLATERAL CIRCULATION AFTER ACUTE ARTERIAL-OCCLUSION

The survival of tissues in the presence of arterial occlusion is criti cally dependent on the development of collateral blood vessels. Identi fication of the biochemical mediators and their mechanism of action is fundamental to an understanding of the evolution of the collateral ci rculation. The ability of PDGF-BB to promote this was evaluated in an animal model of hind limb ischaemia. In order to obtain significant qu antities of this mitogen for use in our animal model, human recombinan t PDGF-BB was expressed in a Chinese Hamster Ovary (CHO) cell line. Th e transfected CHO cells produced 544 mu g/l of PDGF-BB in serum free m edium (SFM). The 30 kDa form of PDGF-BB was purified to homogeneity as judged by silver staining and amino-acid sequencing. Purified PDGF-BB was shown to be bioactive by a cell proliferation assay. The exogenou s administration of PDGF-BB enhanced the recovery of blood flow after acute arterial occlusion. The results suggest that PDGF-BB may have th erapeutic value in promoting collateral development following arterial occlusion.