Rutgers School of Public Health associate professor, Dr. Stephan Schwander, along with his colleagues found seasonal changes in the chemical composition of particulate matter (PM) from rainy and dry seasons may account for observed differences in biological responses. The new study examines the impact seasons have on urban air pollution and tuberculosis (TB) diagnoses.
The study took place in Iztapalapa, a highly populated TB-endemic municipality of Mexico City with elevated outdoor air pollution levels. The researchers examine whether in vitro exposure to urban air pollution PM alters human immune responses to Mycobacterium tuberculosis (M.tb). The team collected PM monthly from rainy, cold-dry and warm-dry seasons. Researchers evaluated the effects of seasonality and size of PM on cytotoxicity and antimycobacterial host immunity in human peripheral blood mononuclear cells (PBMC) from interferon gamma (IFN-γ) release assay (IGRA)+ and IGRA- healthy study subjects.
Researchers found seasonal and size variations in PM-induced cytotoxicity. Urban PM-induced cytotoxicity predominantly relates to PM dose, size and season. Analysis of PM composition showed significant differences in organic and inorganic components between different seasonal PM. Evidence suggests seasonal changes in the chemical composition of PM from rainy and dry seasons may account for observed differences in biological responses to M.tb.Tags: Friday Letter Submission, Publish on July 26