title: Standardization of house dust mite extracts in Korea.
abstract: OBJECTIVE
  House dust mites are the most important cause of respiratory allergy in Korea. Standardization of allergen extracts is essential for improving diagnostics and immunotherapeutics. This study was undertaken to evaluate the allergenicity of standardized house dust mite allergen extracts from Korean house dust mite isolates.
  
  
  METHODS
  Allergen extracts were prepared from cultured Korean house dust mites (Dermatophagoides farinae and D. pteronyssinus). Allergenic activities of Korean house dust mite extracts were compared to standardized extracts from a company in the United States whose allergen concentrations were expressed as Allergy Units (AUs). Specifically, we compared group 1 and 2 major allergens using two-site enzyme-linked immunosorbent assay (ELISA) kits and an in vivo intradermal test.
  
  
  RESULTS
  Major allergen concentrations were 17.0 µg/mg (5.0 µg/mg of Der f 1 and 12.0 µg/mg of Der f 2) for a D. farinae extract and 24.0 µg/mg (11.6 µg/mg of Der p 1 and 12.4 µg/mg of Der p 2) for a D. pteronyssinus extract. Using chloramphenicol (CAP) inhibition assays, AUs were 12.5 AU/µg for a D. farinae extract and 12.8 AU/µg for a D. pteronyssinus extract. Allergenic activities were 3- to 4-fold stronger when assessed by intradermal skin tests for in vivo standardization.
  
  
  CONCLUSIONS
  Allergen extracts were prepared from Korean house dust mites and the allergenicities of the extracts were estimated using AU measurements. House dust mite extracts prepared in this study could be utilized as a reference material, which will be useful for the development of diagnostic and immunotherapeutic reagents in Korea.
authors.affiliation: Department of Internal Medicine and Institute of Allergy, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Kyoung Yong
authors.initials: KY
authors.lastname: Jeong
authors.forename: Soo-Young
authors.initials: SY
authors.lastname: Choi
authors.forename: Jae-Hyun
authors.initials: JH
authors.lastname: Lee
authors.forename: In-Yong
authors.initials: IY
authors.lastname: Lee
authors.forename: Tai-Soon
authors.initials: TS
authors.lastname: Yong
authors.forename: Joo-Shil
authors.initials: JS
authors.lastname: Lee
authors.forename: Chein-Soo
authors.initials: CS
authors.lastname: Hong
authors.forename: Jung-Won
authors.initials: JW
authors.lastname: Park
keywords: Allergen; house dust mite; standardization