Clinical evaluation of commercial conjugates for direct immunofluorescence of herpes simplex virus

Commercially prepared antibody conjugates that are now available allow extensive application of direct immunofluorescence for diagnosing herpetic infections. Five of these conjugates--Microbiological Associates bivalent herpes antiserum (MBA-bivalent), MBA anti-herpes types 1 (MBA-1) and 2 (MBA-2), and Flow Laboratories anti-herpes types 1 (Flow-1) and 2 (Flow-2)--were compared for antibody titer, diagnostic accuracy, and nonspecific background staining on known infected tissue. Four of these were tested simultaneously on 75 clinical specimens. No attempt was made to differentiate between herpes simplex virus type 1 or type 2 infections. All antisera were comparable in titer and exhibited fluorescence with both herpes simplex virus types 1 and 2 antigens. The most significant difference was excessive nonspecific staining consistently seen with the MBA-2 conjugate. Overall, Flow-2 and MBA-bivalent antisera were preferable.