Effect of glutaraldehyde on the humoral immunogenicity and structure of porcine dermal collagen membranes

Objectives: Our previous studies showed that the biodegradation rate of cross-linked porcine dermal collagen membrane (PDCM) could be retarded without changing its biocompatible character. The purpose of this study was to assay the humoral immune response of PDCM reconstitute with glutaraldehyde (GA) and observe their surface architectures. Methods: PDCM reconstituted with GA (0, 0.01, 0.05, and 3%) was implanted in 30 Sprague–Dawley rats. Sample sera were collected 3, 6, and 9 weeks after surgery and assayed with ELISA. The architectures of PDCMs were observed under SEM (100×). Results: The study showed that non cross-linked PDCM induced the highest immune response than any other cross-linked PDCMs (by optical density (OD) values, P<0.05). It also possessed the most active cross-reactivity to the serum of rats from any other PDCMs groups (by Sheffe test, P<0.05). The surface architectures observed under SEM presented four structures: fibrillar, porous, channeled, and sheet-like structures as PDCM was conditioned with 0, 0.01, 0.05, and 3% GA, respectively. Conclusions: Resulting from the study are that changing the concentration of GA can modulate the surface characters of PDCMs and change their immunogenicity. Reconstitution of PDCM may not change the conformation of antigenic determinants of PDCM but rather hinder the epitopes by changing the surface stereo structure of this collagen.