Cross-reactivity between decellularized porcine corneal lamellae for corneal xenobridging and subsequent corneal allotransplants
The purpose of this study is to investigate cross-reactivity between hypertonic saline-treated decellularized porcine corneal lamellae for corneal xenobridging and subsequent corneal allotransplants. Five Chinese rhesus macaques, which had undergone anterior partial thickness corneal transplantation using hypertonic saline-treated decellularized porcine corneal lamellae in preceding experiments, were used as recipients for subsequent full-thickness corneal allografts. To determine whether sensitization of recipients to xenoantigens leads to cross-reactivity against alloantigens, we compared; (i) allogeneic one-way mixed lymphocyte reaction (MLR) of peripheral blood mononuclear cells (PBMCs) from xeno-sensitized recipients with that of PBMCs from naïve rhesus macaques, and (ii) amounts of IgG antibodies that bound to the PBMCs of a rhesus panel (five monkeys) before and after xeno-sensitization. Graft survival and immunologic profiles including memory T-cell subsets and donor rhesus-specific antibodies were also evaluated. No hyperacute or acute rejection was observed within a month of subsequent allotransplantation in any recipient. Alloreactivity by MLR was not different between xeno-sensitized rhesus recipients and naïve rhesus monkeys. Panel-reactive IgG antibodies were unchanged after xeno-sensitization, and no change in donor rhesus-specific antibodies was observed in any recipient. No significant changes in memory T-cell subsets were observed during the early post-operative period in any recipient. Decellularized porcine corneal lamellae may not increase cross-reactivity to alloantigens, and thus, porcine corneal lamellae may be used as a bridge to subsequent corneal allografting.