title: Blood transmission studies of prion infectivity in the squirrel monkey (Saimiri sciureus): the Baxter study.
abstract: BACKGROUND
  Four secondary transmissions of variant Creutzfeldt-Jakob disease (vCJD) infectivity have been associated with the transfusion of nonleukoreduced red blood cells collected from vCJD patients during the asymptomatic phase of the disease. Establishing efficient experimental models for assessing the risk of future transmissions of vCJD infectivity via blood transfusion is of paramount importance in view of a study of archived appendix samples in which the prevalence of asymptomatic vCJD infection in the United Kingdom was estimated at approximately 1 in 2000 of the population. In this study, we investigated transmission of vCJD and sporadic CJD (sCJD) infectivity from blood using the squirrel monkey, which is highly susceptible to experimental challenge with human prion disease.
  
  
  METHODS
  Whole blood collected from vCJD- and sCJD-infected squirrel monkeys was transfused at multiple time points into recipient squirrel monkeys. Blood recipients were euthanized approximately 7 years after their first blood transfusion.
  
  
  RESULTS
  No clinical or pathologic signs of a prion disease were observed in either the sCJD- or the vCJD-transfused monkeys, and immunohistochemistry and biochemical investigations showed no PrP(TSE) in central nervous system or lymphoreticular tissues. Similarly, monkeys inoculated intracerebrally (IC) and intravenously (IV) with either buffy coat or plasma from vCJD and sCJD patients failed to develop disease. However, white blood cells from a chimpanzee-passaged strain of human Gerstmann-Sträussler-Scheinker (GSS) disease transmitted autopsy-proven disease to two IC-inoculated monkeys after incubation periods of 34 and 39 months.
  
  
  CONCLUSIONS
  Blood transmits GSS but not sCJD or vCJD infectivity to IC- or IV-inoculated squirrel monkeys within a 7-year observation period.
authors.affiliation: National CJD Research & Surveillance Unit, Centre for Clinical Brain Sciences, University of Edinburgh, Western General Hospital, Edinburgh, Scotland.
authors.forename: Diane L
authors.initials: DL
authors.lastname: Ritchie
authors.affiliation: College of Medicine, University of South Alabama, Mobile, Alabama.
authors.forename: Susan V
authors.initials: SV
authors.lastname: Gibson
authors.affiliation: University of Texas MD Anderson Cancer Center, Bastrop, Texas.
authors.forename: Christian R
authors.initials: CR
authors.lastname: Abee
authors.affiliation: Global Pathogen Safety, Baxalta, Formerly Baxter BioScience, Vienna, Austria.
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Kreil
authors.affiliation: National CJD Research & Surveillance Unit, Centre for Clinical Brain Sciences, University of Edinburgh, Western General Hospital, Edinburgh, Scotland.
authors.forename: James W
authors.initials: JW
authors.lastname: Ironside
authors.affiliation: National Institute of Neurological Diseases and Stroke, National Institutes of Health, Bethesda, Maryland.
authors.forename: Paul
authors.initials: P
authors.lastname: Brown
mesh_terms: D000818:Animals; D007562:Creutzfeldt-Jakob Syndrome / Q000635:transmission*; D006801:Humans; D066298:In Vitro Techniques; D007962:Leukocytes; D012453:Saimiri; D065227:Transfusion Reaction