Loss of corneal Langerhans cells during storage in organ culture medium, Optisol and McCarey-Kaufman medium.

Purpose: This study compares the influence of different corneal preservation media on HLA-DR positive corneal Langerhans cells (LCs).
Methods: Using fluorescence-associated immunohistochemistry, corneal sections were stained for HLA-DR antigens after preserving corneal-scleral discs in three different storage media: organ culture medium. Optisol and McCarey-Kaufman medium. HLA-DR positive LCs were present in corneal epithelium and upper stroma of fresh corneas.
Results: A storage period of even 3 days had a significant influence on the number of HLA-DR positive corneal LCs. The number of LCs decreased at the limbus from 15.3 +/- 4.1 LCs/ 0.25 mm2 to 11.8 +/- 1.2 LCs/0.25 mm2 (p < 0.01) during preservation in McCarey-Kaufman medium, to 11.2 +/- 1.9 LCs/0.25 mm2 (p < 0.01) during preservation in organ culture medium and to 12.7 +/- 3.4 LCs/0.25 mm2 (p < 0.01) during preservation in Optisol. A greater loss was detected after 7 days and we found a cell number of 1.6 +/- 1.1 LCs/0.25 mm2 (p < 0.001) after storage in organ culture medium and of 1.4 +/- 1.5 LCs/0.25 mm2 (p < 0.001) after storage in Optisol. The donor tissues entirely lacked HLA-DR positive LCs, regardless of the preservation medium used, when stored for up to 14 days.
Conclusion: These results demonstrate that loss of HLA-DR antigens is mainly related to storage period and is independent of the type of preservation medium and preservation temperature.