Immunological safety evaluation of a haemostatic agent and wound dressing made of horse collagen fibrils.

A haemostatic agent and wound dressing made of horse collagen (Tachotop) was applied to guinea-pigs in such a way that the intended use of this material in humans was simulated, and cell-mediated and humoral immune responses of the animals were investigated. In addition, immune reactions were forcefully induced in guinea-pigs in order to validate the methodical approach and quantitate the observed reactions. Cell-mediated immunity was measured as delayed-type hypersensitivity skin reactions, and antibodies were detected by an enzyme-linked immunosorbent assay (ELISA). Simulation of the intended application of this haemostyptic material did not induce immune reactions in guinea-pigs even under critical conditions. The animals could only be immunized when the antigen was administered in solution or finely dispersed and together with adjuvant. Immune reactions thus induced were specific for collagen, no reaction was obtained against possible impurities such as albumin, immunoglobulin or fibronectin. It is concluded--in accordance with clinical experience--that this material is very unlikely to induce immune reactions upon clinical application to humans.