IL17A and Allergy: In mice receiving antibiotics and inoculated with S. pneumoniae and K. pneumoniae, the microbiome promotes a widespread innate response to airway infection by pathogens, stimulates clearance, and enhances host survival during infections, most likely due to a signaling axis that involves IL-17 and GM-CSF; last is a key factor for immunological regulation that prevents colonization by pathogens and has great importance in allergy mechanisms [35].