The expression of hepatitis-C virus antigen by immunohistochemical stain and polymerase chain reaction in corneas of seropositive corneal donors.

Background: Of the donor corneas rejected for transplantation, the largest group is that from donors testing seropositive for hepatitis C virus (HCV). In situations of severe shortage in supply of donor corneal tissue, we may consider the use of seropositive donors for transplantation if we can prove with high certainty the absence of HCV RNA in the donor corneal tissue. Polymerase chain reaction (PCR) is a highly sensitive and specific technique for direct detection of HCV RNA and can be used for this purpose. Nevertheless, it is not applicable for routine clinical use in most eye departments due to its unavailability and cost effectiveness. Purpose: To study the possible use of immunohistochemical method for detection of HCV antigen in corneal tissue of seropositive donors and correlate the results with those of PCR. Immunohistochemical methods have not yet been studied in donor corneal tissue. Materials and methods: Eight corneas of 4 seropositive and 8 corneas of 4 seronegative corneal donors were studied by immunohistochemical and PCR methods for the presence of HCV antigen in their corneal tissue and sera. Results: HCV RNA was not detected in the sera and corneal tissue of all seropositive and seronegative corneal donors by either PCR and immunohistochemical methods. Conclusion: Although the study is too small for conclusive results, the correlation between the immunohistochemical and PCR studies for direct detection of HCV antigen in corneal tissue of seropositive donors may raise the possibility of using the immunohistochemical method for screening of donor corneas for the detection of HCV antigen. A larger prospective study investigating the sensitivity, specificity and clinical applicability of the immunohistochemical method is warranted.