Protein G HP SpinTrap columns will be used to capture IgG antibodies from patient serum pre-implant, between 2 weeks-3 months, between 3-11 months and between 12-18 months post-implant. These antibodies will be cross-linked to the column and then protein extracted from implant tissue (ie Native bovine/porcine pericardium) will be deglycosylated and run through the column. Antigenic proteins will be trapped and non-antigenic proteins will be washed through the column. These antigenic proteins will be eluted off the column and identified using LC-MS/MS. The proteins identified in the pre-implant elutant will be compared to the proteins in post-implant elutant to identify xenoantigens. Success criteria will be method validation by identification of previously known and new currently unknown xenoantigens.
