biostudies-literatureUnknown14(2)Marrocco R<h4>Background</h4>Immunotherapy has had limited success in pancreatic cancer, largely due to a low mutational burden and immunosuppressive microenvironment. Here we hypothesized that systemic delivery of viral antigens can redirect pre-existing antiviral immunity against pancreatic tumors.<h4>Methods</h4>Cytomegalovirus (CMV, a β-herpesvirus) was chosen, as the majority of the population is infected and it induces an extremely large/broad memory T-cell response. Mice latently infected with murine CMV (MCMV) were orthotopically implanted with pancreatic cancer cells and treated with systemic injections of MCMV T-cell epitopes. Tumor growth was monitored by ultrasound two times a week, and immune cell infiltration was analyzed by histology, flow cytometry and single-cell RNA sequencing (scRJournal for immunotherapy of cancere012969https://www.ebi.ac.uk/biostudies/studies/S-EPMC12927352biostudies-literatureRedirecting cytomegalovirus immunity against pancreas cancer for immunotherapy.PMC12927352Gulay KMaia CLowy AMartsinkovskiy AJaljuli MLucero-Meza ESalu PMose EBenedict CSun SHurtado de Mendoza TMarrocco RBrunel SPatel JMedari RfalseRedirecting cytomegalovirus immunity against pancreas cancer for immunotherapy.<h4>Background</h4>Immunotherapy has had limited success in pancreatic cancer, largely due to a low mutational burden and immunosuppressive microenvironment. Here we hypothesized that systemic delivery of viral antigens can redirect pre-existing antiviral immunity against pancreatic tumors.<h4>Methods</h4>Cytomegalovirus (CMV, a β-herpesvirus) was chosen, as the majority of the population is infected and it induces an extremely large/broad memory T-cell response. Mice latently infected with murine CMV (MCMV) were orthotopically implanted with pancreatic cancer cells and treated with systemic injections of MCMV T-cell epitopes. Tumor growth was monitored by ultrasound two times a week, and immune cell infiltration was analyzed by histology, flow cytometry and single-cell RNA sequencing (scR2026-01-01T00:00:00Z2026 Feb2026-07-16T18:26:32.348Z2026-07-09T11:14:25.838ZS-EPMC129273524163887110.1136/jitc-2025-012969