title: Skin localization of cow's milk proteins delivered by a new ready-to-use atopy patch test.
abstract: OBJECTIVE
  Atopy patch tests (APTs) allow the detection of delayed allergies at the skin level. The localization of beta-lactoglobulin delivered into the skin by an innovative ready-to-use APT (E-patch was investigated and the efficacy and safety of this device were assessed.
  
  
  METHODS
  The E-patch containing beta-lactoglobulin was placed for 24 h in contact with hairless rat skin mounted in a Franz diffusion cell. Transdermal passage was monitored by measurement of beta-lactoglobulin A-[methyl-(14)C] or by two-site enzyme immunoassay. An iterative skin stripping allowed measurement of the beta-lactoglobulin penetrating the first external skin layers.
  
  
  RESULTS
  After 24 h, 92% of beta-lactoglobulin remained on the skin. The iterative skin strippings showed a 135-fold higher concentration of beta-lactoglobulin in the stratum corneum than that found in the epidermis-dermis. Analysis of the solution in the receiver compartment by radioactivity assays or immunoassays indicates that intact protein did not cross the skin.
  
  
  CONCLUSIONS
  The E-patch system allows native beta-lactoglobulin to concentrate in the stratum corneum, in the vicinity of immunological cells, but does not lead to its systemic delivery. Therefore, it is suggested that this delivery system creates ideal conditions for promoting a positive topical response with reduced risk of systemic anaphylactic reactions caused by the native form of the beta-lactoglobulin A.
authors.affiliation: Laboratoire de Physico-Chimie, Pharmacotechnie et Biopharmacie, UMR CNRS, Châtenay-Malabry Cedex, France. delphine.soury@cep.u-psud.fr
authors.forename: D
authors.initials: D
authors.lastname: Soury
authors.forename: G
authors.initials: G
authors.lastname: Barratt
authors.forename: S
authors.initials: S
authors.lastname: Ah-Leung
authors.forename: P
authors.initials: P
authors.lastname: Legrand
authors.forename: H
authors.initials: H
authors.lastname: Chacun
authors.forename: G
authors.initials: G
authors.lastname: Ponchel
mesh_terms: D000818:Animals; D002417:Cattle; D005260:Female; D007124:Immunoenzyme Techniques; D007782:Lactoglobulins / Q000493:pharmacokinetics; D016269:Milk Hypersensitivity / Q000175:diagnosis*; D008894:Milk Proteins / Q000008:administration & dosage / Q000493:pharmacokinetics*; D010328:Patch Tests; D051381:Rats; D012867:Skin / Q000378:metabolism*; D012869:Skin Absorption
chemical_list: D007782:Lactoglobulins; D008894:Milk Proteins