Intravenous BCG Induction of Innate Memory in Young Pigs

Abstract Exposure to vaccine strain of Mycobacterium bovis(M. bovis), Bacillus Calmette-Guerin (BCG), alters innate immune cells through epigenetic and metabolic modifications resulting in heightened responses subsequent microbial insult (innate memory). As a biomedical model for human disease, pigs provide critical space study the role memory disease resistance. Young were inoculated intravenous (IV) or intraperitoneal (IP) with either live heat-inactivated BCG (IV-live, IP-live, IV-inactive, noBCG groups). At 2wks post inoculation, monocyte production IL-1β nor TNF cytokines following ex vivostimulation LPS was not different any group compared noBCG, i.e. no memory. dose lower than anticipated, at 3wks primary all second time respective preparations routes BCG. Ex vivocytokine stimulated monocytes measured again 5wks inoculation (2wks post-secondary inoculation) both elevated IV-live memory), but IP-live IV-inactive groups. Additionally, PBMC homologous recall antigen (purified proteins from M. bovis) resulted 3-fold higher IFNγ response IV-inactive. Together these data suggest that while can induce state young pigs, induction training cannot be inferred by T cell protein antigen. continue highlight as valuable multiple factors (i.e. route, dose, viability) may need considered USDA-ARS CRIS project 5030-32000-225-000D