Rejected human corneal grafts. II. Light and electron microscopic study

Area of Science:

• Ophthalmology
• Immunology
• Histopathology

Background:

• Corneal transplantation is a common procedure.
• Graft rejection remains a significant challenge in corneal transplantation.
• Understanding the cellular and structural basis of rejection is crucial for improving outcomes.

Purpose of the Study:

• To investigate the microstructural alterations in rejected human corneal grafts.
• To identify the types of immune cells involved in corneal graft rejection.
• To elucidate the characteristic pathological changes associated with graft failure.

Main Methods:

• Systematic light and electron microscopy of six rejected human corneal grafts.
• Analysis of corneas from a cohort of 40 'bad-risk' corneal transplants.
• Histopathological examination of epithelial, endothelial, and stromal layers.

Main Results:

• Consistent fine structural similarities were observed across all studied rejected grafts.
• Infiltration by granulocytes, lymphocytes, and plasma cells was a common finding.
• Characteristic pathological alterations were identified in the epithelial and endothelial linings and the corneal stroma.

Conclusions:

• The observed cellular infiltrates and tissue alterations strongly suggest an active immunological rejection process.
• The findings indicate a recipient-mediated immune response against the donor corneal tissue.
• These microstructural insights contribute to understanding the mechanisms of corneal graft failure.