Open Access Research article

No H- and L-type cases in Belgium in cattle diagnosed with bovine spongiform encephalopathy (1999-2008) aging seven years and older

Alexandre Dobly1*, Jan Langeveld2, Lucien van Keulen2, Caroline Rodeghiero1, Stéphanie Durand1, Riet Geeroms1, Patrick Van Muylem1, Jessica De Sloovere1, Emmanuel Vanopdenbosch1 and Stefan Roels1

Author Affiliations

1 Pathology and Prionology, Veterinary and Agrochemical Research Centre, Brussels, Belgium

2 Central Veterinary Institute of Wageningen UR, Lelystad, The Netherlands

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BMC Veterinary Research 2010, 6:26  doi:10.1186/1746-6148-6-26

Published: 21 May 2010



The bovine spongiform encephalopathy (BSE) epidemic presented homogeneity of the phenotype. This classical BSE (called C-type) was probably due to the contamination of the food chain by a single prion strain. However, due to the active surveillance and better techniques, two rare variants of BSE have been recently reported in different continents without a clear correlation to the BSE epidemic. These emerging types behave as different strains of BSE and were named H-type and L-type according to the high and low molecular mass of the unglycosylated fragment of their proteinase K resistant prion protein (PrPres). In these types, the proportion of the un-, mono- and di-glycosylated fragments of PrP (glycoprofile) is also atypical and represents an effective diagnostic parameter. This study evaluated the presence of such types in bovine of 7 years and older in Belgium.


The Belgian BSE archive contained 41 bovines of at least 7 years of age. The biochemical features of their PrPres were analyzed by Western blot with five antibodies recognising different regions of PrPres, from N- to C-terminus: 12B2, 9A2, Sha31, SAF84 and 94B4. All antibodies clearly detected PrPres except 12B2 antibody, which is specific for N-terminal region 101-105, a PrP region that is only retained in H-types. The glycoprofiles did correspond to that of C-type (with more than 55% of diglycosylated PrPres using antibody 94B4). Therefore, all cases have the features of C-type BSE.


This study supports that, among the BSE cases of 7 years and older identified in Belgium, none was apparently of the H- or L- type. This is consistent with the very rare occurrence of atypical BSE and the restricted dimension of Belgium. These results shed some light on the worldwide prevalence of atypical BSE.