Efficacy of Pig-to-Rhesus Lamellar Corneal Xenotransplantation

Abstract

Purpose: : To investigate the efficacy of pig-to-nonhuman primate lamellar corneal transplantation using both decellularized and fresh porcine corneas in order to assess feasibility as a substitute for human.

Methods: : Nine Chinese rhesus macaques underwent lamellar corneal transplantation using both decellularized (n=5) and fresh (n=4) porcine corneas. Minimal immunosuppression was applied using topical and systemic corticosteroid. Graft survival and immunologic profiles including T cell subset, anti-α-Gal/donor specific antibodies, and complement were evaluated.

Results: : 80% of decellularized porcine lamellar grafts remained transparent for more than 6 months while half of fresh porcine lamellar grafts developed chronic rejection. Immunologic profile showed enhancement of memory T cell in both groups, and variable increases in anti-α-Gal/donor specific antibodies case-by-case. Activated complement in the aqueous was significantly higher in recipients with rejected grafts compared than in recipients with survived grafts. CD8 effector T cells tend to be elevated in the recipients with rejected graft.

Conclusions: : Decellularized porcine cornea is likely to be a promising substitute to human corneal allograft. Xenogeneic corneal rejection may be associated with CD8 T cell and complement mediated reaction in primates.

Keywords: transplantation • cornea: basic science • cornea: clinical science