How air pollution with PM25 affect the pulmonary immune system to favor infections ? 9233

Abstract Description Air pollution represents a major risk to public health, affecting millions of people around the world. Among its many harmful impacts, the increased susceptibility to respiratory infections is particularly concerning. Fine particles and other atmospheric pollutants can weaken the immune system, thereby facilitating the invasion and spread of pathogens. This study explores the mechanisms by which air pollution exacerbates vulnerability to infections, highlighting the complex interactions between pollutants and the immune response. The aim of this project is to demonstrate the impact of PM2.5 particles on the pulmonary immune system. Therefore, a murine model of exposure to PM2.5 and infection by Streptococcus pneumoniae (Sp) was established. Our results show a deficiency in the immune system, increased inflammation characterized by significant recruitment of immune cells and production of pro-inflammatory cytokines, as well as a defect in bacterial clearance in the lungs of mice exposed to PM2.5. Furthermore, exposure to PM2.5 particles appears to alter the major functions of human macrophages, including endocytosis and bactericidal activity. This would explain the increased susceptibility to infections described in epidemiological studies. The results of this study suggest that air pollution, and more specifically PM2.5 particles, compromise the immune system’s ability to effectively combat respiratory infections Topic Categories Innate Immune Responses and Host Defense: Cellular Mechanisms (INC)