Application of immunoperoxidase-based techniques to detect herpesvirus infection in tortoises

Indirect (IIP) and direct (DIP) immunoperoxidase assays were developed for the serological and histological diagnoses of herpesvirus infection in tortoises, respectively. A, mouse monoclonal antibody (MAb HL1546), specific for the heavy chain of tortoise IgY, was used as the secondary antibody in the IIP assay. Rabbit polyclonal antisera raised against 2 sucrose gradient-purified tortoise herpesvirus isolates (HV4295/7R/95 and HV1976) were used as primary antibodies for the detection of herpesvirus antigen either in infected cell cultures or in formalin-fixed, paraffin-embedded tissues. The HP and DIP assays could detect either the presence of anti-herpesvirus antibody in the plasma of exposed tortoises or the presence of herpesvirus antigen in infected tissues, respectively. Although the UP test complements the enzyme-linked immunosorbent assay and the serum neutralization test already available for measuring herpesvirus-specific antibody in tortoises, the DIP test is useful for the histological diagnosis of herpesvirus infection in tortoises.