Protective immunity and subsequent parasite expulsion during N. brasiliensis infection is driven by a Th2 response that is orchestrated by the secretion of cytokines such as IL-4, IL-5 and IL-13 and characterised by eosinophilia, mastocytosis, goblet cell hyperplasia and concurrent mucus and antibody production [19], [20]. This evidence concerns the gene IL5 and mastocytosis.