Molecular and Biological Characterization of a New Isolate of Guinea Pig Cytomegalovirus

• Main Authors: Mark R. Schleiss, Shane McAllister, Anibal G. Armién, Nelmary Hernandez-Alvarado, Claudia Fernández-Alarcón, Jason C. Zabeli, Thiruvarangan Ramaraj, John A. Crow, Michael A. McVoy
• Format: Article
• Language: English
• Published: MDPI AG 2014-01-01
• Series: Viruses
• Subjects: guinea pig cytomegalovirus; cytomegalovirus strain variation; CMV immune evasion; congenital cytomegalovirus infection; congenital CMV vaccines
• Online Access: http://www.mdpi.com/1999-4915/6/2/448

Development of a vaccine against congenital infection with human cytomegalovirus is complicated by the issue of re-infection, with subsequent vertical transmission, in women with pre-conception immunity to the virus. The study of experimental therapeutic prevention of re-infection would ideally be undertaken in a small animal model, such as the guinea pig cytomegalovirus (GPCMV) model, prior to human clinical trials. However, the ability to model re-infection in the GPCMV model has been limited by availability of only one strain of virus, the 22122 strain, isolated in 1957. In this report, we describe the isolation of a new GPCMV strain, the CIDMTR strain. This strain demonstrated morphological characteristics of a typical Herpesvirinae by electron microscopy. Illumina and PacBio sequencing demonstrated a genome of 232,778 nt. Novel open reading frames ORFs not found in reference strain 22122 included an additional MHC Class I homolog near the right genome terminus. The CIDMTR strain was capable of dissemination in immune compromised guinea pigs, and was found to be capable of congenital transmission in GPCMV-immune dams previously infected with salivary gland‑adapted strain 22122 virus. The availability of a new GPCMV strain should facilitate study of re-infection in this small animal model.