In vitro infectivity assay for prion titration for application to the evaluation of the prion removal capacity of biological products manufacturing processes

A Simple, Versatile and Sensitive Cell-Based Assay for Prions from Various Species

“…In sharp contrast to the other cell lines previously used to titrate mouse [18] and sheep prions [50], no subcultivation of inoculated RK13 epithelial cultures is required before analysis. This unique feature is a crucial operational advantage as serial passaging of inoculated cultures is very time-consuming and costly, especially when assaying large numbers of samples.…”

“…This unique feature is a crucial operational advantage as serial passaging of inoculated cultures is very time-consuming and costly, especially when assaying large numbers of samples. For example, inoculated MovS cultures [51] have to be passaged 8 times for optimal PG127 detection [50]. In addition, the slow down of cell division may participate in high sensitivity of the assay as cell division was reported to decrease steady state levels of PrP res [52].…”

Biopotency Assays: an Integrated Application to Quality Control of Chinese Materia Medica

“…In Chinese Pharmacopoeia (Pharmacopoeia Committee of P. R. China, 2010) and United States Pharmacopoeia (United States Pharmacopeial Convention, 2012), the potency of recombinant human glucagon and somatropin must be determined in the manufacture process. Biopotency assay in vitro can be used to evaluate the bioactivity of drugs on organs, tissues, microorganisms, enzymes, and cells with a series of detection methods (You et al, 2010;Pauly et al, 2009;Coombes et al, 2009). Each of the two assays has its own characteristics.…”

Decontamination of prions in a plasma product manufacturing environment

“…The risk of vCJD transmission through plasma‐derived medicinal products (PDMPs) remains theoretical, since prion infectivity might be present in human plasma, as is the case in animal models . Therefore, the manufacturing processes have been optimized to provide a significant safety margin for PDMP: numerous studies conducted by multiple investigators using experimental models of prion infectivity (using either bioassays or cells infectivity assays—for example, the tissue culture infectivity assay [TCIA]) or the surrogate Western blot [WB] assay and scaled‐down manufacturing processes have shown that many of these process steps possess considerable prion removal capacity and would remove large quantities of the theoretical prion contaminant in human plasma (for review, see Burnouf et al . and Flan et al.…”

“…The current report describes an extensive series of investigational studies on the evaluation of sodium hydroxide (NaOH), currently the most widely used and considered the most effective chemical agent for prion decontamination, at various concentrations, temperatures, and exposure times. Its effect was evaluated on several matrices contaminated with model prion strains (263K and 127S) and the relevant vCJD strain, using the classical WB, an infectivity bioassay on relevant animal models and an innovative cell‐based infectivity assay called TCIA . This report is intended to present effective procedures compatible with routine application in an industrial plasma fractionation setting.…”