Most humans mount significant Immunoglobulin E responses only as a defense against parasitic infections .
In technical terms , an allergen is an antigen capable of stimulating a type - I hypersensitivity reaction in atopic individuals through Immunoglobulin E ( IgE ) responses .
Most humans mount significant IgE   responses only as a defense against parasitic infections .
In technical terms , an allergen is an antigen capable of stimulating a type - I hypersensitivity reaction in atopic individuals through Immunoglobulin E ( IgE ) responses .