title: Ex vivo induction of mRNA in human whole blood as a new platform of drug and dietary supplement development.
abstract: OBJECTIVE
  We introduced a new concept of ex vivo gene expression analysis (Mitsuhashi, Clin Chem 53:148-149, 2007), where drug action was simulated under physiological conditions. This model system was applied to study various fields of drug development.
  
  
  METHODS
  Heparinized human whole blood was incubated with drugs for less than 4h. The changes of specific mRNA were then quantified using the method we developed (Mitsuhashi, Tomozawa, Endo, and Shinagawa, Clin Chem 52:634-642, 2006).
  
  
  RESULTS
  The mRNA quantitation method was used as a model system to study the following areas: (1) identification of respondents and non-respondents, (2) ex vivo compound screening, (3) determination of individually optimized doses, (4) drug-to-drug comparison, (5) assessment of leukocyte toxicity, (6) discovery of molecular targets, (7) assessment of the action of dietary supplements, and (8) characterization of respondents and non-respondents for various dietary supplements.
  
  
  CONCLUSIONS
  Since ex vivo assays are safe, a large number of healthy donors and disease patients can be recruited to identify individual-to-individual variations, which is not available from current preclinical study models. Although each system should be validated using a large number of samples, the ex vivo analysis will be a new tool for the development of drugs and dietary supplements in future.
authors.affiliation: Hitachi Chemical Research Center Inc, Irvine, CA, USA, mmitsuhashi@HCRcenter.com
authors.forename: Masato
authors.initials: M
authors.lastname: Mitsuhashi
authors.forename: Mieko
authors.initials: M
authors.lastname: Ogura
authors.forename: Katsuya
authors.initials: K
authors.lastname: Endo
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Obara
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Izutsu
authors.forename: Stephan R
authors.initials: SR
authors.lastname: Targan
authors.forename: Motoko
authors.initials: M
authors.lastname: Maemura
authors.forename: Daisuke
authors.initials: D
authors.lastname: Tachikawa
authors.forename: Atsushi
authors.initials: A
authors.lastname: Shinagawa
mesh_terms: D017931:DNA Primers; D019587:Dietary Supplements; D004305:Dose-Response Relationship, Drug; D004353:Drug Evaluation, Preclinical / Q000379:methods*; D006801:Humans; D066298:In Vitro Techniques; D020382:Interleukin-18 / Q000096:biosynthesis; D007376:Interleukin-2 / Q000096:biosynthesis; D007962:Leukocytes / Q000187:drug effects; D010835:Phytohemagglutinins / Q000494:pharmacology; D012333:RNA, Messenger / Q000032:analysis / Q000096:biosynthesis* / Q000097:blood* / Q000235:genetics; D011948:Receptors, Antigen, T-Cell / Q000502:physiology; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis / Q000235:genetics
chemical_list: D017931:DNA Primers; D020382:Interleukin-18; D007376:Interleukin-2; D010835:Phytohemagglutinins; D012333:RNA, Messenger; D011948:Receptors, Antigen, T-Cell; D014409:Tumor Necrosis Factor-alpha