|Hall, S Mark|
Submitted to: BMC Research Notes
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/9/2011
Publication Date: 9/29/2011
Citation: Porcario, C., Hall, S.M., Martucci, F., Corona, C., Iulini, B., Perazzini, A.Z., Acutis, P., Hamir, A.N., Loiacono, C.M., Greenlee, J.J., Richt, J.A., Caramelli, M., Casalone, C. 2011. Evaluation of two sets of immunohistochemical and Western blot confirmatory methods in the detection of typical and atypical BSE cases. BMC Research Notes. 4:376. Interpretive Summary: A study was done to compare diagnostic techniques utilized in Italy and the U.S. for the detection of bovine spongiform encephalopathy (BSE.). To allow for optimal comparison of these techniques samples from both countries were tested. These samples came from cattle with confirmed cases of BSE of the classical, H, or L subtypes. The techniques employed were immunohistochemical staining and western blot analysis of brain tissue derived from the obex region. The Italian and U.S. techniques were each able to detect the abnormal prion protein, and the immunohistochemical staining techniques demonstrated similar distribution, patterns, and intensity of staining for all samples examined. The Italian and U.S. western blot procedures both were able to appropriately identify and categorize BSE tissues by subtype. This work demonstrates that despite using techniques based on different reagent systems and antibodies both the Italian and U.S. methods are adequate for use in BSE diagnostics.
Technical Abstract: Aims: To compare the ability of the Italian and the U.S. bovine spongiform encephalopathy (BSE) confirmatory protocols in the detection of classical (C-) and atypical - low (L-) and high (H-) type- BSE forms. Methods and Results: Obex samples from U.S. and Italian C-type BSE cases, a U.S. H-type and an Italian L-type BSE case were tested in parallel by both the Italian and the U.S. immunohistochemical (IHC) and Western blot (WB) methods. The Italian and the U.S. IHC techniques were equivalent to detect PrP**Sc distribution, deposition pattern and intensity of staining on the classical as well as the atypical (L- and H- type) BSE cases examined. Both the Italian and the U.S. WB procedures were consistent in the identification of classical and atypical BSE forms. Conclusions: The Italian and the U.S. BSE confirmatory methods provided comparable results in correctly identifying and discriminating among C-, L- and H-type BSE forms. Significance and impact of the study: The U.S. BSE confirmatory protocols were proven for the first time to be effective in properly identifying the L-type BSE form. This finding helps to validate the suitability of the BSE confirmatory tests currently in place in the U.S. and Italy for BSE surveillance.