[Rejection of corneal allografts]

Area of Science:

• Ophthalmology
• Immunology
• Transplantation Science

Context:

• Corneal graft rejection is the leading cause of penetrating keratoplasty (corneal transplant) failure.
• The process involves a complex immune response where the host recognizes donor alloantigens, targeting the graft.
• Endothelial rejection represents the most severe form, potentially leading to graft failure.

Purpose:

• To summarize the immunological mechanisms, risk factors, and management strategies for corneal graft rejection.
• To highlight the importance of early detection and preventive measures in corneal transplantation.
• To discuss the role of tissue matching and immunosuppressive therapies in improving graft survival.

Summary:

• Corneal rejection is an immune response against donor antigens, with endothelial rejection being the most severe.
• Risk factors include donor and host characteristics.
• Corticosteroids are the standard treatment, while other immunosuppressants require further study.
• Preventive strategies involve tissue matching (ABO and HLA compatibility, especially in high-risk patients) and early intervention.

Impact:

• Improved understanding of corneal rejection mechanisms can lead to better diagnostic tools.
• Optimized immunosuppressive protocols and tissue matching can enhance corneal graft survival rates.
• Reducing graft failure rates through effective rejection management improves visual outcomes for patients undergoing corneal transplantation.