Research progress on effects of air pollution on pollinosis and its mechanisms

Pollinosis is one of the common allergic diseases, and its morbidity continues to increase. Studies have demonstrated that air pollution is a key environmental factor that leads to the increased prevalence of pollinosis. Air pollutants and pollen allergens exert synergistic effects in stimulating allergic responses in susceptible individuals. In this article, we analyzed the relationship between air pollution and pollinosis based on the latest studies, and elaborated potential mechanisms on how air pollution increases the incidence of pollinosis and aggravates allergic reactions. Air pollutants can increase both pollen production and the levels of allergenic proteins, and enhance allergenicity of pollen allergens through structural alterations or chemical modifications. The potential mechanisms of air pollutants exacerbating pollen allergies are as follows: Air pollutants may disrupt the barrier function of the respiratory epithelium and facilitate the penetration of pollen allergens into deeper tissues. Additionally, they may accelerate the process of the release of pollen allergy-related cytokines, promoting T helper 2 (Th2) cell differentiation and exacerbating inflammatory responses in the airways. Given the limitations of existing research, future prospective studies are needed to explore the effects of mixed pollutants and different types of pollutants on pollen, and the response mechanisms of allergy-related cells and cytokines to different pollutant categories. The findings would provide a comprehensive understanding of the impacts of air pollution on pollen allergies and scientific evidence for effective protection of the heath of pollinosis patients.