Abstract: Methods for producing biological solutions such as immunoglobulins and in particular anti-D immunoglobulin substantially free of abnormal prion protein resulting therefrom. Specifically provided are methods for aggregation of prions and depth filtration of the biological solution to capture and remove abnormal and if desired, normal prion protein. The prion protein may then be eluted from the depth filter and filter washes and concentrated sufficient for detection at limits currently required by available assays.

Abstract: The solvent-detergent (S/D) process is used to inactivate enveloped viruses in plasma products. While concentrations of 1.0% detergent and 0.3% tri-n-butyl phosphate solvent have been considered necessary for robust removal of viral activity, we show the effectiveness of solvent-detergent treatment after fractionation and nanofiltration of an immune gamma globulin preparation, which required significantly reduced concentrations of solvent and detergent. Reduced levels of solvent and detergent lead to greater efficiencies in their removal post-inactivation with the potential for greater yields and decreased processing costs.

Abstract: Methods for producing immunoglobulins and in particular anti-D immunoglobulin substantially free of prion and virus, and product resulting therefrom. Specifically provided are methods for nanofiltration of the anti-D immunoglobulin in high ionic strength buffer and with excipient such as polysorbate 80. Additional steps include diafiltration to concentrate the anti-D protein and reduce the concentration of excipient present.