Test: Tissue Immunohistochemistry for HHV-6
Immunohistochemistry (IHC) is useful when analyzing tissue samples for active herpesvirus infections. A tissue biopsy is taken from the patient, fixed in formalin, embedded in paraffin wax and then cut into sections that are placed on a slide. IHC analysis allows detection of viral antigens early in the course of the disease when cytopathic changes have not yet developed.
Paraffin-embedded tissue sections sent for analysis are rehydrated prior to staining. A blocking step is used to block non-specific staining between the primary antibodies and the tissue. An antigen retrieval procedure may be used to enhance detection of the viral proteins. Commercial monoclonal antibodies directed toward the viral proteins of interest are then applied directly to the tissues. Labeled secondary antibodies allow the visualization of the viral protein within infected cells. One slide will be stained with Hemotoxylin & Eosin (H&E).