Research progress in the off-target effects of Bacille Calmette-Guérin vaccine

• Published in: Chinese medical journal Vol. 137; no. 17; pp. 2065 - 2074
• Main Authors: Wu, Yanfei, Zhang, Xiaoyin, Zhou, Li, Lu, Jiayu, Zhu, Fengcai, Li, Jingxin
• Format: Journal Article
• Language: English
• Published: Hagerstown, MD Lippincott Williams & Wilkins 05.09.2024; Lippincott Williams & Wilkins Ovid Technologies; School of Public Health, Southeast University, Nanjing, Jiangsu 210009, China%Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, Jiangsu 210009, China%IB Course Center of High School Affiliated to Shanghai Jiaotong University, Shanghai 200439, China%NHC Key Laboratory of Enteric Pathogenic Microbiology, Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, Jiangsu 210009, China%Institute of Global Public Health and Emergency Pharmacy, China Pharmaceutical University, Nanjing, Jiangsu 210009, China; Wolters Kluwer
• Subjects: Bacterial infections; BCG Vaccine - immunology; BCG Vaccine - therapeutic use; Bladder cancer; Clinical trials; Coronaviruses; COVID-19; Cross-sectional studies; Cytokines; Drug dosages; Epidemiology; Hepatitis B; Herpes viruses; Hospitalization; Human papillomavirus; Humans; Immunotherapy; Infant mortality; Infections; Infectious diseases; Leprosy; Malaria; Older people; Review; Systematic review; Tuberculosis; Tuberculosis - immunology; Tuberculosis - prevention & control; Vaccines; Viral infections; Warts; Greece; Egypt; Indonesia; Spain; Infections; Trained immunity; Off-target effects of vaccines; Autoimmune diseases; BCG vaccine; Non-muscle-invasive bladder cancer
• ISSN: 0366-6999; 2542-5641; 2542-5641
• DOI: 10.1097/CM9.0000000000002890

Abstract Bacille Calmette-Guérin (BCG) vaccine is designed to provide protection against tuberculosis (TB). However, numerous epidemiological, clinical, and immunological studies have shown that BCG vaccination affects neonatal and infant mortality, which may be related to the reduction of TB-unrelated infections and diseases by BCG vaccine. We aimed to discuss the off-target effects of BCG vaccine on un-TB infections and diseases, as well as the potential mechanism and influencing factors. Literature was retrieved mainly from PubMed using medical subject headings "BCG, variations, and non-specific, heterologous or off-target". Studies have showed that BCG vaccination can prevent various heterologous infections, including respiratory tract infections, leprosy, and malaria, treat viral infections including human papillomavirus and herpes simplex virus infection as immunotherapy, and improve the immune responses as vaccine adjuvant. Besides, BCG vaccine can reduce the recurrence rate of non-muscle-invasive bladder cancer, and may provide protection against autoimmune diseases. These off-target effects of BCG vaccine are thought to be achieved by modulating heterologous lymphocyte responses or inducing trained immunity, which were found to be sex-differentiated and affected by the BCG vaccine strains, sequence or time of vaccination.