Abstract of Oral Presentation
Pdgfra-positive fibroblasts are a major site of mouse cytomegalovirus latency in vivo.
Latent cytomegalovirus (CMV) infections pertain to most of the human population, yet our understanding of the cell types that carry latent CMV in vivo remains limited. While endothelial cells and macrophages have been identified previously as sites of latency, it remains unclear if they are the main latency reservoir. Here, using the mouse model of latent CMV infection, we assessed the prevalence of latent mouse CMV (MCMV) genomes in highly purified populations of fibroblasts, endothelial cells and tissue-resident macrophages across multiple organs and following distinct infection routes. We describe organ-specific and infection route-specific patterns of viral genome distribution in tissue-resident cells. Strikingly, platelet-derived growth factor receptor alpha (Pdgfra)-positive fibroblasts contained the highest MCMV genome load in most organs and conditions analysed. We define this state as latent infection on the basis of weak and stochastic viral gene transcription as well as virus reactivation from Pdgfra-positive fibroblasts ex vivo. On the population level, Pdgfra-positive fibroblasts supported both productive and latent MCMV infection. In sum, these results reveal that non-hematopoietic cells are a common site of MCMV latency in vivo.
Katarzyna M. Sitnik1, Henrike Maaß1, Natascha Gödecke1, Yeonsu Kim1, Fran Krstanović2, Ilija Brizić2, Luka Čičin-Šain1
1 Department of Viral Immunology, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany
2 Center for Proteomics, Faculty of Medicine, University of Rijeka, 51000 Rijeka, Croatia