Reduction of the antigenicity and immunogenicity of xenografts by a new cross-linking reagent.

To overcome the disadvantages of glutaraldehyde (GA), new cross-linking reagents, polyepoxy compounds (PC), were introduced and their effects on the antigenicity and immunogenicity of biomaterials were investigated. In the qualitative study, antigenicity of type I collagen in bovine arteries treated with GA or glycerol polyglycidyl ether (GPE), a kind of PC, was detected using a fluorescent antibody technique. To evaluate the immunogenicity quantitatively, DDY mice were twice immunized with homogenates of GA, GPE, or untreated dog arteries. Using their sera collected 10 and 90 days after the last immunization as primary antibodies, the dogs' peripheral lymphocytes were stained with FITC labeled anti-mouse IgG antibodies against shared antigens on arteries and lymphocytes. Percentages of stained lymphocytes were then analyzed with flow cytofluorometry. In both qualitative and quantitative studies, extremely low antigenicity and immunogenicity were shown in GA or GPE treated arteries. It is therefore suggested that GPE is an ideal cross-linking reagent for vascular and valvular xenografts and is applicable to clinical use.