title: Preparation and characterization of an extract of german cockroach from a korean source.
abstract: OBJECTIVE
  The cockroach (CR) is an important cause of respiratory allergic disorders. We prepared a German CR extract in a standardized way and analyzed its allergenic properties.
  
  
  METHODS
  The extract was prepared from German CR (Blattella germanica) obtained from a Korean colony, and its allergenic activity was compared with that of the commercial Hollister-Stier (HS) extract. The concentrations of Bla g 1 and Bla g 2 were measured, and an in vitro specific IgE binding inhibition assay was performed to assess IgE reactivity. Proteolytic activity was examined by gelatin zymography.
  
  
  RESULTS
  Bla g 1 and Bla g 2 were detected at 405 U/mg and 273 ng/mg, respectively, in the Korean extract, and at 187 U/mg and 56 ng/mg, respectively, in the HS extract. The Korean extract showed 94.2% inhibition of IgE reactivity, as compared with the HS extract. A similar pattern of IgE-reactive bands was detected for the two extracts, indicating that their allergenic components are similar. The proteolytic activities of the Korean and HS extracts were found to be similar in gelatin zymography. The endotoxin levels in the Korean and HS extracts were 3,440 EU/mL and 6,580 EU/mL, respectively.
  
  
  CONCLUSIONS
  The German CR extract was prepared in a standardized way. The extract produced in this study will be useful for the development of allergy diagnostics and immunotherapeutic agents.
authors: Department of Internal Medicine and Institute of Allergy, Yonsei University College of Medicine, Seoul, Korea.
authors: Kyoung Yong
authors: KY
authors: Jeong
authors: Soo-Young
authors: SY
authors: Choi
authors: Jae-Hyun
authors: JH
authors: Lee
authors: Joo-Shil
authors: JS
authors: Lee
authors: Tai-Soon
authors: TS
authors: Yong
authors: Chein-Soo
authors: CS
authors: Hong
authors: Jung-Won
authors: JW
authors: Park
keywords: Allergen; German cockroach; Korea; standardization