IL33 and allergic asthma: Furthermore, H. polygyrus exosomes suppressed expression of IL1RL1/ST2 (the IL-33-specific receptor subunit) following treatment in vitro in intestinal epithelial cells and in vivo during the allergic asthma response to Alternaria. As the IL-33 ligand–receptor interaction is known to be important in antihelminthic responses 63, 64, these data suggest the ability of H. polygyrus exosomes to modulate aspects of the host cell response to prevent pathogen clearance.