Biochemical characterization of autologous fibrin sealants produced by CryoSeal and Vivostat in comparison to the homologous fibrin sealant product Tissucol/Tisseel.

Different principles for production of "autologous fibrin sealant" have been established, and commercial devices employing these methods are nowadays available and used in clinical routine. Users might anticipate for these autologous fibrin sealants features comparable to commercial homologous fibrin sealants, used in surgical routine for many years. However, only little is known about biochemical properties, formation, cross-linking and stability of fibrin sealant clots produced for autologous use with the aid of commercially available devices. We have investigated protein composition, formation and stability of clots obtained from autologuous fibrin sealants produced with commercially available devices (CryoSeal and Vivostat) and compared these parameters to those of the industrially produced homologous fibrin sealant Tissucol/Tisseel. The CryoSeal product is a mixture of many plasma proteins; the Vivostat product and Tissucol/Tisseel appear as comparatively pure plasma derivatives. The products differ in their protein composition and concentrations, including their concentration in fibrin. Significant fibrin alpha and gamma-chain cross-linking by FXIIIa occurs only in Tissucol/Tisseel clots. In test tubes CryoSeal and Vivostat (tranexamic acid-free formulation) fibrin clots liquefy within 1-2 days, but Vivostat (tranexamic acid containing formulation) clots were stable for 4 days and showed partial liquefaction after 5 days. Tissucol/Tisseel clots, containing the protease inhibitor aprotinin, appeared unchanged over the observation period of 5 days. In an in vitro model mimicking in vivo conditions (diffusion of protease inhibitors and proteolytic digestion) clot liquefaction occurs at day 1 for all autologous fibrin sealants clots, with an observable delay for the tranexamic acid containing Vivostat, and day 5 for Tissucol/Tisseel clots. Characterization of the CryoSeal and Vivostat fibrin sealants and Tissucol/Tisseel and their performance show a clear difference in biochemical properties.