IL13 and mastocytosis: Second, intestinal nematodes including Ascaris (80), scabies mites (81), and Trichomonas vaginalis (82, 83) are able to modulate the host immune response with production of classical Th2 cytokines, IL-4, IL-5, and IL-13, mastocytosis, eosinophilia, IgE, and alternatively-activated macrophages known to play a critical role in tissue repair (84).