Succinylated collagen crosslinked by thermal treatment for coating vascular prostheses

Vascular prostheses coated with collagen carefully prepared to avoid contamination were tested to see if it could induce endothelial cell lining throughout the graft surface in a natural way. The collagen fibers were succinylated. Hydrogel produced with the succinylated collagen was used for the sealant to reduce the amount of solid substance. To avoid contamination and the side effects of chemical reagents, the collagen thermally crosslinked under sterile conditions. A suspension of the collagen fibers was enmeshed in the interstices of Dacron fibers of fabric prostheses, which were then thermally crosslinked at 130 degrees C for 20 h. The prostheses were porous when the collagen fiber network was dry. Under wet conditions, however, the water permeability of the grafts was reduced to 0.1 ml/min from the 1,250 ml/min of the original prostheses. Three weeks after implantation in the abdominal aortas of dogs, 81.2 +/- 11% of the luminal surface was macroscopically thrombus free, and 56 +/- 14% was endothelialized. More than 95% of the coated collagen had been absorbed. Numerous fibroblasts had migrated into the graft walls, and capillary blood vessels had infiltrated the inside of the graft walls without foreign body reaction. In the controls, thrombus free areas averaged 9.0 +/- 5%, and endothelialized areas averaged 5.2 +/- 4%. Many giant cells, plasma cells, and lymphocytes had migrated into the graft walls, but no fibroblasts. These results suggest that rapid endothelialization is possible when clean collagen is used.