Murine cytomegalovirus gene amplification and culture after submaxillary salivary gland biopsy

Abstract

An important target tissue for murine cytomegalovirus (CMV) infection is the submaxillary salivary gland. Submaxillary salivary gland biopsy specimens from BALB/c mice latently infected with murine CMV were examined for murine CMV DNA by in vitro enzymatic amplification using the polymerase chain reaction preceding oligonucleotide hybridization. The amplified sequence was a 152-base pair segment from within the immediate early gene of murine CMV. Biopsy and whole gland specimens from acutely infected BALB/c mice and latently infected, immunosuppressed BALB/c mice were compared for active murine CMV infection. After acute infection with murine CMV, virus was recovered in all cultures of both biopsy and whole salivary gland specimens but from none of the latently infected animals. Reactivated virus was detected by culture of both biopsy (90%) and whole salivary gland specimens (100%) from latently infected mice that received antithymocyte serum. Viral nucleic acid was detected in 90% of biopsy specimens from latently infected animals. Hence, active murine CMV infection can be detected in biopsy specimens from mice with acute and reactivated infection and murine CMV DNA can be amplified and detected in salivary gland biopsy specimens from latently infected animals. Biopsy of this or other target tissues can be useful for obtaining tissue for viral studies where the survival of the animal is important and it is useful to distinguish latent from acute or reactivated infection.