In the current study, Dr. Rohwer and colleagues looked at the ability of affinity resin chromatography to remove infectious prion particles from the blood of hamsters infected with scrapie.
The technique involves the use of a specific ligand, selected from among millions of possible candidates, that has high binding affinity with both normal and abnormally folded proteins -- in this case, the prion that causes scrapie.
The authors looked at the ability of the affinity resin, labeled L13 and mass-produced version of the same resin, labeled L13A, to remove transmissible spongiform infectivity endogenously present in hamster blood.
They took 500 mL of scrapie-infected hamster whole blood and purged it of white cells using leukoreduction. They then passed the red-cell concentrate through columns of the affinity resins, with each sample getting two pass-throughs. They then tested the samples for infectivity by limiting dilution titration.