Virus inactivation of plasma-derived proteins by pasteurization in the presence of guanidine hydrochloride.
BACKGROUND
Viruses, among them parvovirus B19 and other small, nonenveloped viruses, may be present in human blood and may contaminate plasma-derived therapeutics. Efficient inactivation or removal of such viruses, especially parvoviruses, represents a current problem and corresponding technologies are under investigation. In this report, such a technology is described.


METHODS
A recently developed pasteurization of human apolipoprotein A-I (apoA-I), which is performed at 60 degrees C for 10 hours in the presence of guanidine hydrochloride (GdnHCl), was validated by using a series of model viruses, including members of the families parvoviridae and picornaviridae. The model viruses were spiked into the apoA-I- and GdnHCl-containing solutions, and virus inactivation was evaluated by infectivity assays in cell cultures. The mechanism of virus inactivation was studied by virus sedimentation analysis using the picornavirus model.


RESULTS
All viruses tested were inactivated to levels below the limit of detection, although different inactivation kinetics were obtained for the different viruses. The mechanism of virus inactivation by this pasteurization was disassembly of the virus particles into single proteins or small noninfectious viral subunits.


CONCLUSIONS
The pasteurization validated in this report has the potential to inactivate a wide range of transfusion-relevant viruses including parvoviruses and picornaviruses.
ZLB Bioplasma AG, Bern, Switzerland.
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A
Schlegel
A
A
Immelmann
C
C
Kempf
D000818:Animals; D016632:Apolipoprotein A-I; D001769:Blood / Q000821:virology*; D001799:Blood Sedimentation; D002460:Cell Line; D002522:Chlorocebus aethiops; D004770:Enterovirus / Q000187:drug effects; D019791:Guanidine / Q000494:pharmacology*; D007700:Kinetics; D008915:Minute Virus of Mice / Q000187:drug effects; D009994:Osmolar Concentration; D012709:Serum Albumin / Q000187:drug effects; D013242:Sterilization / Q000379:methods*; D013696:Temperature; D014709:Vero Cells; D014771:Virion / Q000187:drug effects; D014775:Virus Activation / Q000187:drug effects*; D014780:Viruses / Q000187:drug effects
D016632:Apolipoprotein A-I; D012709:Serum Albumin; D019791:Guanidine