title: Standardization of the methods and reference materials used to assess virus content in varicella vaccines.
abstract: BACKGROUND
  In Korea, every vaccine lot is tested by the National Center for Lot Release (NCLR) in accordance with the national lot release procedures to ensure the safety and efficacy of vaccines. These quality tests examine the virus content in varicella vaccines via plaque assays (either the agar overlay method [AOM] or plaque staining method [PSM]), according to the procedures suggested by the Korean Reference Material for the Varicella Vaccine (KRMVV) or the manufacturer's standard in-house protocol.
  
  
  OBJECTIVE
  To standardize the virus content tests, viral titers in the KRMVV were measured using the PSM at four participating laboratories in a collaborative study. With the aim of developing a standardized method using the KRMVV as a positive control, we compared the ability of the two test methods, AOM and PSM, to accurately and reproducibly determine the virus content of two commercial varicella vaccines.
  
  
  RESULTS
  The results showed that the standardized method (PSM) was more suitable for quality control analysis of the varicella vaccine.
  
  
  CONCLUSIONS
  Use of a standardized method (PSM) according to the Korean reference material will improve the reliability and objectivity of lot release testing.
authors.affiliation: Vaccines division, National Institute of Food & Drug Safety Evaluation, Ministry of Food and Drug Safety, Cheongju-si, 363-700, Republic of Korea. eca_dee@hanmail.net.|Department of Laboratory Animal Medicine, College of Veterinary Medicine, Seoul National University, Seoul, 151-742, Republic of Korea. eca_dee@hanmail.net.
authors.forename: JiYoung
authors.initials: J
authors.lastname: Hong
authors.affiliation: Vaccines division, National Institute of Food & Drug Safety Evaluation, Ministry of Food and Drug Safety, Cheongju-si, 363-700, Republic of Korea. ohojung@korea.kr.
authors.forename: Ho Jung
authors.initials: HJ
authors.lastname: Oh
authors.affiliation: Vaccines division, National Institute of Food & Drug Safety Evaluation, Ministry of Food and Drug Safety, Cheongju-si, 363-700, Republic of Korea. cosmos0925@korea.kr.
authors.forename: Naery
authors.initials: N
authors.lastname: Lee
authors.affiliation: Vaccines division, National Institute of Food & Drug Safety Evaluation, Ministry of Food and Drug Safety, Cheongju-si, 363-700, Republic of Korea. dickykim@korea.kr.
authors.forename: Do-Keun
authors.initials: DK
authors.lastname: Kim
authors.affiliation: Vaccines division, National Institute of Food & Drug Safety Evaluation, Ministry of Food and Drug Safety, Cheongju-si, 363-700, Republic of Korea. h3035@korea.kr.
authors.forename: Heui-Seong
authors.initials: HS
authors.lastname: Yoon
authors.affiliation: Vaccines division, National Institute of Food & Drug Safety Evaluation, Ministry of Food and Drug Safety, Cheongju-si, 363-700, Republic of Korea. potpol1770@naver.com.
authors.forename: Yeon-Tae
authors.initials: YT
authors.lastname: Kim
authors.affiliation: Vaccines division, National Institute of Food & Drug Safety Evaluation, Ministry of Food and Drug Safety, Cheongju-si, 363-700, Republic of Korea. skchang@korea.kr.
authors.forename: Seokkee
authors.initials: S
authors.lastname: Chang
authors.affiliation: Department of Laboratory Animal Medicine, College of Veterinary Medicine, Seoul National University, Seoul, 151-742, Republic of Korea. pjhak@snu.ac.kr.
authors.forename: Jae-Hak
authors.initials: JH
authors.lastname: Park
authors.affiliation: Vaccines division, National Institute of Food & Drug Safety Evaluation, Ministry of Food and Drug Safety, Cheongju-si, 363-700, Republic of Korea. hjchung58@korea.kr.
authors.forename: Hyejoo
authors.initials: H
authors.lastname: Chung
mesh_terms: D019433:Chickenpox Vaccine / Q000276:immunology*; D006801:Humans; D015203:Reproducibility of Results; D056910:Republic of Korea; D013678:Technology, Pharmaceutical / Q000379:methods* / Q000592:standards*; D019562:Viral Load / Q000379:methods* / Q000592:standards*; D010948:Viral Plaque Assay / Q000379:methods / Q000592:standards
chemical_list: D019433:Chickenpox Vaccine