IGHE and escherichia coli infection: E. coli infection before AAD phase, significantly attenuated allergic symptoms of nasal rubbing and sneezing, decreased the pathology of eosinophil infiltration and goblet cell metaplasia in the nasal mucosa and lung, inhibited serum OVA-specific IgE levels, and suppressed levels of Th2 cytokines in NALF and BALF.