Project description:Trained immunity is the phenomenon whereby innate immune cells such as monocytes or macrophages undergo functional reprogramming after exposure to certain microbial components, altering their responses to future exposures. Intravesical instillation with Bacillus Calmette-Guérin (BCG) is the most effective adjuvant therapy in patients with high-risk non-muscle invasive bladder cancer (HR-NMIBC). HR-NMIBC is associated with a high risk of tumor recurrence and progression to muscle-invasive bladder cancer. The precise immunological mechanisms through which BCG mediates anti-tumor immunity are still unclear. The aim of our study was to investigate the (long-term) induction of trained immunity by repeated BCG instillations in NMIBC patients and elucidate the immunological and epigenetic mechanisms that are involved. Another aim was to assess the relationship between trained immunity response and clinical response of NMIBC patients, in terms of recurrence free survival and progression free survival. To determine whether BCG instillations induce trained immunity in peripheral blood mononuclear cells (PBMCs) we performed a prospective cohort study (‘Tribute’) and isolated PBMCs collected before BCG therapy and at 8 time points during BCG therapy. A total of 17 BCG-naïve HR-NMIBC patients were included. After isolation of PBMCs, monocytes were further purified using an isolation procotol with a percoll gradient. RNA was isolated from these purified monocytes were and used as input for RNA-seq analysis.
Project description:Trained immunity is the phenomenon whereby innate immune cells such as monocytes or macrophages undergo functional reprogramming after exposure to certain microbial components, altering their responses to future exposures. Intravesical instillation with Bacillus Calmette-Guérin (BCG) is the most effective adjuvant therapy in patients with high-risk non-muscle invasive bladder cancer (HR-NMIBC). HR-NMIBC is associated with a high risk of tumor recurrence and progression to muscle-invasive bladder cancer. The precise immunological mechanisms through which BCG mediates anti-tumor immunity are still unclear. The aim of our study was to investigate the (long-term) induction of trained immunity by repeated BCG instillations in NMIBC patients and elucidate the immunological and epigenetic mechanisms that are involved. Another aim was to assess the relationship between trained immunity response and clinical response of NMIBC patients, in terms of recurrence free survival and progression free survival. To determine whether BCG instillations induce trained immunity in peripheral blood mononuclear cells (PBMCs) we performed a prospective cohort study (‘Tribute’) and isolated PBMCs collected before BCG therapy and at 8 time points during BCG therapy. A total of 17 BCG-naïve HR-NMIBC patients were included. After isolation of PBMCs, monocytes were further purified using an isolation procotol with a percoll gradient. RNA was isolated from these purified monocytes were and used as input for RNA-seq analysis.
Project description:The protective effects of the tuberculosis vaccine Bacillus Calmette-Guerin (BCG) on unrelated infections are thought to be mediated by long-term metabolic changes and chromatin remodeling through histone modifications in innate immune cells such as monocytes, a process termed trained immunity. Here, we show that BCG induction of trained immunity in monocytes is accompanied by a strong increase in glycolysis and, to a lesser extent, glutamine metabolism, both in an in-vitro model and after vaccination of mice and humans. Pharmacological and genetic modulation of rate-limiting glycolysis enzymes inhibits trained immunity, changes that are reflected by the effects on the histone marks (H3K4me3 and H3K9me3) underlying BCG-induced trained immunity. These data demonstrate that a shift of the glucose metabolism toward glycolysis is crucial for the induction of the histone modifications and functional changes underlying BCG-induced trained immunity. The identification of these pathways may be a first step toward vaccines that combine immunological and metabolic stimulation.
