IL4 and parasitic infectious disease: The traditional view of basophils as pro-inflammatory effector cells providing mediators (histamine) and cytokines (IL-4/IL-13) to induce and/or amplify a Th2 response in parasite infection and allergy has been further questioned recently by studies showing that after binding to the H2 receptor, histamine enhanced anti-inflammatory IL-10 production by dendritic cells (48).