We developed an effective method for detecting prion (PrP) antigenic determinants remaining in bovine meat and bone meal (MBM) using pressurized fluid extraction (PSE) equipment and the flow microbead immunoassay (FMI). With the FMI, bovine recombinant PrP could be determined quantitatively in the 7 pmol-7 nmol range using anti-PrP peptide polyclonal antibody-coupled microbeads and anti-PrP monoclonal antibody (SAF61) as detection antibody. PSE extraction at 120ºC for 5 min under high pressure was the most effective way to elute PrP determinants from bovine MBMs. The FMI was capable of detecting PrP determinants in bovine MBM extracts with high specificity and indicated that the MBMs contained high levels of PrP determinants. This assay was also applied to the detection of PrPSc determinants in bovine MBM spiked with scrapie-infected brain at a weight ratio of 50:1. These data indicate that this assay was effective for the specific detection of PrP determinants contained in bovine MBM extracts.
(Prion Research Team, Prion Disease Research Center, TEL +81-29-838-8333)
Reference:
Murayama et al. (2006) J. Appl. Microbiol. 101:369-376.
