Complex sentence: However, these parasites can become coated with IgE and recognized by FcεRI on the surface of eosinophils that releases preformed mediators, such as major basic protein, against which helminths are not resistant.
Split into simpler sentences: However, these parasites can become coated with IgE and recognized by FcεRI on the surface of eosinophils. Activated eosinophils release preformed mediators, such as major basic protein, against which helminths are not resistant.