title: Ethosome formulations of known contact allergens can increase their sensitizing capacity.
abstract: Vesicular systems, such as liposomes and ethosomes, are used in cosmetic and pharmaceutical products to encapsulate ingredients, to protect ingredients from degradation, to increase bioavailability, and to improve cosmetic performance. Some reports have suggested that formulation of cosmetic ingredients in vesicular carrier systems may increase their contact allergy elicitation potential in humans. However, no sensitization studies have been published. We formulated two model contact allergens (isoeugenol and dinitrochlorobenzene) in ethosomes and investigated the sensitization response using a modified local lymph node assay (LLNA). The results were compared with those for the same allergens in similar concentrations and vehicles without ethosomes. Both allergens encapsulated in 200-300 nm ethosomes showed increased sensitizing potency in the murine assay compared with the allergens in solution without ethosomes. Empty ethosomes were non-sensitizing according to LLNA. The clinical implications are so far uncertain, but increased allergenicity from ethosome-encapsulated topical product ingredients cannot be excluded.
authors.affiliation: National Allergy Research Centre, Department of Dermatology and Allergy Centre, Odense University Hospital, Odense, Denmark. jakobtorp@dadlnet.dk
authors.forename: Jacob Torp
authors.initials: JT
authors.lastname: Madsen
authors.forename: Stefan
authors.initials: S
authors.lastname: Vogel
authors.forename: Ann-Therese
authors.initials: AT
authors.lastname: Karlberg
authors.forename: Carl
authors.initials: C
authors.lastname: Simonsson
authors.forename: Jeanne D
authors.initials: JD
authors.lastname: Johansen
authors.forename: Klaus E
authors.initials: KE
authors.lastname: Andersen
mesh_terms: D000485:Allergens / Q000008:administration & dosage* / Q000276:immunology; D000818:Animals; D049109:Cell Proliferation / Q000187:drug effects*; D002626:Chemistry, Pharmaceutical; D017449:Dermatitis, Allergic Contact / Q000209:etiology* / Q000276:immunology; D004137:Dinitrochlorobenzene / Q000008:administration & dosage* / Q000276:immunology; D004305:Dose-Response Relationship, Drug; D004339:Drug Compounding; D005054:Eugenol / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000276:immunology; D005260:Female; D007114:Immunization; D008081:Liposomes; D023441:Local Lymph Node Assay; D008198:Lymph Nodes / Q000187:drug effects* / Q000276:immunology / Q000473:pathology; D051379:Mice; D008808:Mice, Inbred CBA; D010316:Particle Size
chemical_list: D000485:Allergens; D004137:Dinitrochlorobenzene; D008081:Liposomes; D005054:Eugenol; C036643:isoeugenol