title: Worms as therapeutic agents for allergy and asthma: understanding why benefits in animal studies have not translated into clinical success.
abstract: Helminth infections are associated with decreased rates of autoimmunity and allergy, and several clinical studies have demonstrated that intentional infection with helminths can reduce symptoms of autoimmune diseases. In contrast, though numerous animal studies have demonstrated that helminth infections ameliorate allergic diseases, clinical trials in humans have not shown benefit. In this article, we review in detail the 2 human studies that have prospectively tested whether helminth infections protect against allergy. We next review the research designs and results obtained from animal studies, and compare these to the human trials. We then postulate possible reasons for the lack of efficacy observed in clinical trials to date and discuss potential future areas of research in this field.
authors.affiliation: Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, Md.
authors.forename: Holly
authors.initials: H
authors.lastname: Evans
authors.affiliation: Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, Md. Electronic address: edward.mitre@usuhs.edu.
authors.forename: Edward
authors.initials: E
authors.lastname: Mitre
mesh_terms: D000818:Animals; D000947:Antigens, Helminth / Q000276:immunology; D001249:Asthma / Q000276:immunology* / Q000628:therapy*; D002986:Clinical Trials as Topic; D006373:Helminthiasis / Q000276:immunology; D006376:Helminths / Q000276:immunology*; D006801:Humans; D006967:Hypersensitivity / Q000276:immunology* / Q000628:therapy*; D007167:Immunotherapy
chemical_list: D000947:Antigens, Helminth
keywords: Allergy; animal models; asthma; atopy; clinical trials; helminths; hygiene hypothesis; therapeutics