Examination of the Offspring of a Japanese Cow Affected with L-Type Bovine Spongiform Encephalopathy
Takashi YOKOYAMA1), Hiroyuki OKADA1), Yuichi MURAYAMA1), Kentaro MASUJIN1), Yoshifumi IWAMARU1) and Shirou MOHRI1)
1) Prion Disease Research Center, National Institute of Animal Health
(Received 2-Jun-2010) (Accepted 11-Aug-2010)
ABSTRACT. The offspring of a beef cow affected with L-type bovine spongiform encephalopathy (L-BSE) was kept in a pen at a BSE-dedicated animal facility till the offspring was 48 months of age. The steer was then euthanized and subjected to a test for BSE. The abnormal isoform of the prion protein was not detected in the brain and spinal cord of the steer. Transmission of L-BSE was not observed during 4 years of observation, though the steer was born when the dam was in the terminal stages of the disease.
KEY WORDS: atypical BSE, L-BSE, offspring, prion
Bovine spongiform encephalopathy (BSE), a neurodegenerative 29 disorder, is caused by prions . Use of prion-contaminated meat and bone meal is known to cause a BSE pandemic. Horizontal transmission of BSE between cattle has not been observed, and there is little data to support the existence of maternal transmission . The incidence of BSE has declined owing to disease-control programs such as feed bans. These programs are based on epidemiological and/or experimental data obtained for classical BSE (C-BSE). However, different phenotypes of BSE—designated as atypical BSEs—have been detected in aged cattle. Atypical BSEs are classified into 2 forms on the basis of the molecular weight of the proteinase K-resistant core fragment of the abnormal prion protein PrPSc: L-type BSE (L-BSE) or bovine amyloidotic spongiform encephalopathy and H-type BSE (H-BSE) [3, 5]. Several studies have indicated that L-BSE and H-BSE are caused by different prions with varying biological characteristics [4, 11, 12]. A limited number of atypical BSE cases have been reported, and sporadic occurrence may be supposed as their origin . Therefore, greater attention should be paid to BSE control programs.
The second Japanese case of atypical BSE was reported in a 14-year-old beef cow (BSE/JP24) in 2006. The PrPSc glycoprofile and existence of prion protein (PrP) plaques were different from those observed in C-BSE . Although this case was firstly reported as L-type-like BSE , further study showed it was similar to European L-BSE. Thereafter, this case was referred as L-BSE . Cattle  and mice overexpressing bovine PrP  that had been experimentally challenged with L-BSE had a shorter incubation period and exhibited more severe spongiform changes in the brain than the mice and cattle that had been experimentally challenged with C-BSE. These results suggest that the L-BSE prion exhibits greater virulence in cattle than the C-BSE prion.
In this study, the dam (BSE/JP24) developed astasia because of dislocation of the hip and a fracture in the hindlimb. The cow delivered after 7 days, that is, 17 days before the due date; therefore, artificial delivery was performed. The owner reared the calf, but the mother cow was slaughtered 4 days after delivery and found to be affected with BSE by a routine BSE test at the abattoir. The time course of this case is shown in Table 1.
The offspring was placed in a BSE cohort and transported to the National Institute of Animal Health, where it was kept in an isolated pen at the animal facility dedicated for experimental cattle with BSE; the offspring was used in a cohort study to determine whether maternal transmission occurs in L-BSE. The study was approved by the Animal Ethics Committee and the Animal Care and Use Committee of the National Institute of Animal Health. The calf had an injured forelimb and a weak constitution. When the animal was 48 months old, its health deteriorated because of chronic rumen impaction, leading to a bad prognosis; subsequently, the animal was euthanized from the ethical viewpoint and dissected.
The necropsy was performed in a dissection room located in a biosafety level 3 facility and was conducted according to the regulations laid down for handling cattle affected with BSE. The rest of the carcass was completely destroyed by incineration. The pattern of PrPSc deposition in L-BSE-affected cattle is different from that observed in C-BSE-affected cattle, and most of the PrPSc in the L-BSE-affected cattle is detected in the frontal cortex and olfactory bulb [5, 6]. Therefore, we examined tissue samples from the medulla oblongata at the obex level, pons, cerebellum, cerebral cortex, olfactory bulb, and 2 regions of the spinal cord. These samples were subjected to confirmatory BSE testing (western blotting and immunohistochemistry). PrPSc was not detected in the brain and spinal cord (Fig. 1). Pathological analysis did not show any PrPSc accumulation and spongiform changes in the brain (data not shown). Although PrPSc may have been detected if the offspring was observed for a longer time, we thought that the offspring was not affected with L-BSE; this supported the result of absence of maternal transmission in this case.
Maternal transmission is thought to be the cause of increased incidence of scrapie in the offspring of scrapie-affected sheep . In contrast, modeling studies indicated that the cumulative risk of maternal transmission of BSE is approximately 2%, but with a confidence interval including zero . Further, the data of a cohort study suggested that the risk of development of BSE in the offspring increases for calves born closer to the onset of disease in the dam . In BSE or scrapie, maternal transmission implies both horizontal (peri- and postnatal) and vertical (prenatal) transmission of prions from mother to offspring, and the precise mechanism remains to be elucidated. In this case, the offspring was born when the dam was considered in a terminal stage of the disease. The steer was kept in a pen but developed astasia because of health deterioration at the age of 48 months. Although this observation period was insufficient, it was thought that maternal transmission did not occur in this case.
The PrPSc distribution pattern in cattle infected with BSE is completely different from that in sheep with scrapie in whom PrPSc was detected in the lymphoid tissues and placenta (13). Scrapie transmission from ewe to lamb probably occurs via the postnatal route. Detection of scrapie infectivity in the placenta  and milk  has supported this hypothesis. Further, PrPSc distribution in cattle experimentally affected with L-BSE was limited to the central nervous system, and little PrPSc accumulation was observed in the peripheral nerve tissue and adrenal gland at the clinical stage . This result was similar to that observed in cattle experimentally affected with C-BSE.
Epidemiological and transmission studies have not revealed any risk of BSE transmission through semen, milk, or embryos . The limited PrPSc accumulation in the BSE-affected dam may be responsible for the absence of maternal transmission in this case.
This is the first case report on an offspring that was delivered when the dam was in the terminal stages of atypical BSE. Studies such as this one—even though labor-intensive—are essential for obtaining scientific data that are important for risk analysis of rare diseases.
We would like to acknowledge the considerable help extended by officers of the Ministry of Agriculture, Forestry and Fisheries and from the Livestock Industry Division and the Livestock Hygiene Service Center at Nagasaki Prefecture; we would also like to acknowledge the cow owner who helped us in obtaining data on the offspring. The authors also thank the animal-care staff at the National Institute of Animal Health, who took care of the cattle, and the members of the Prion Disease Research Center, National Institute of Animal Health, for their help. This study was supported by grants 1rom the BSE control project of the Ministry of Agriculture, Forestry and Fisheries of Japan.
snip...see full text references ;
14th ICID International Scientific Exchange Brochure -
Final Abstract Number: ISE.114
Session: International Scientific Exchange
Transmissible Spongiform encephalopathy (TSE) animal and human TSE in North America
update October 2009
Bacliff, TX, USA
An update on atypical BSE and other TSE in North America. Please remember, the typical U.K. c-BSE, the atypical l-BSE (BASE), and h-BSE have all been documented in North America, along with the typical scrapie's, and atypical Nor-98 Scrapie, and to date, 2 different strains of CWD, and also TME. All these TSE in different species have been rendered and fed to food producing animals for humans and animals in North America (TSE in cats and dogs ?), and that the trading of these TSEs via animals and products via the USA and Canada has been immense over the years, decades.
12 years independent research of available data
I propose that the current diagnostic criteria for human TSEs only enhances and helps the spreading of human TSE from the continued belief of the UKBSEnvCJD only theory in 2009. With all the science to date refuting it, to continue to validate this old myth, will only spread this TSE agent through a multitude of potential routes and sources i.e. consumption, medical i.e., surgical, blood, dental, endoscopy, optical, nutritional supplements, cosmetics etc.
I would like to submit a review of past CJD surveillance in the USA, and the urgent need to make all human TSE in the USA a reportable disease, in every state, of every age group, and to make this mandatory immediately without further delay. The ramifications of not doing so will only allow this agent to spread further in the medical, dental, surgical arena's. Restricting the reporting of CJD and or any human TSE is NOT scientific. Iatrogenic CJD knows NO age group, TSE knows no boundaries. I propose as with Aguzzi, Asante, Collinge, Caughey, Deslys, Dormont, Gibbs, Gajdusek, Ironside, Manuelidis, Marsh, et al and many more, that the world of TSE Transmissible Spongiform Encephalopathy is far from an exact science, but there is enough proven science to date that this myth should be put to rest once and for all, and that we move forward with a new classification for human and animal TSE that would properly identify the infected species, the source species, and then the route.
Wednesday, March 31, 2010
Atypical BSE in Cattle
ALABAMA MAD COW g-h-BSEalabama
In this study, we identified a novel mutation in the bovine prion protein gene (Prnp), called E211K, of a confirmed BSE positive cow from Alabama, United States of America. This mutation is identical to the E200K pathogenic mutation found in humans with a genetic form of CJD. This finding represents the first report of a confirmed case of BSE with a potential pathogenic mutation within the bovine Prnp gene. We hypothesize that the bovine Prnp E211K mutation most likely has caused BSE in "the approximately 10-year-old cow" carrying the E221K mutation.
Saturday, August 14, 2010
BSE Case Associated with Prion Protein Gene Mutation (g-h-BSEalabama) and VPSPr PRIONPATHY (see mad cow feed in COMMERCE IN ALABAMA...TSS)
Monday, August 9, 2010
Variably protease-sensitive prionopathy: A new sporadic disease of the prion protein or just more PRIONBALONEY ?
International Society for Infectious Diseases Web: http://www.isid.org
I ask Professor Kong ;
Thursday, December 04, 2008 3:37 PM Subject: RE: re--Chronic Wating Disease (CWD) and Bovine Spongiform Encephalopathies (BSE): Public Health Risk Assessment
''IS the h-BSE more virulent than typical BSE as well, or the same as cBSE, or less virulent than cBSE? just curious.....''
Professor Kong reply ;
''As to the H-BSE, we do not have sufficient data to say one way or another, but we have found that H-BSE can infect humans. I hope we could publish these data once the study is complete.
Thanks for your interest.''
Qingzhong Kong, PhD Associate Professor Department of Pathology Case Western Reserve University Cleveland, OH 44106 USA
Transmission of atypical BSE in humanized mouse models
Liuting Qing1, Wenquan Zou1, Cristina Casalone2, Martin Groschup3, Miroslaw Polak4, Maria Caramelli2, Pierluigi Gambetti1, Juergen Richt5, Qingzhong Kong1 1Case Western Reserve University, USA; 2Instituto Zooprofilattico Sperimentale, Italy; 3Friedrich-Loeffler-Institut, Germany; 4National Veterinary Research Institute, Poland; 5Kansas State University (Previously at USDA National Animal Disease Center), USA
Background: Classical BSE is a world-wide prion disease in cattle, and the classical BSE strain (BSE-C) has led to over 200 cases of clinical human infection (variant CJD). Atypical BSE cases have been discovered in three continents since 2004; they include the L-type (also named BASE), the H-type, and the first reported case of naturally occurring BSE with mutated bovine PRNP (termed BSE-M). The public health risks posed by atypical BSE were largely undefined.
Objectives: To investigate these atypical BSE types in terms of their transmissibility and phenotypes in humanized mice. Methods: Transgenic mice expressing human PrP were inoculated with several classical (C-type) and atypical (L-, H-, or Mtype) BSE isolates, and the transmission rate, incubation time, characteristics and distribution of PrPSc, symptoms, and histopathology were or will be examined and compared.
Results: Sixty percent of BASE-inoculated humanized mice became infected with minimal spongiosis and an average incubation time of 20-22 months, whereas only one of the C-type BSE-inoculated mice developed prion disease after more than 2 years. Protease-resistant PrPSc in BASE-infected humanized Tg mouse brains was biochemically different from bovine BASE or sCJD. PrPSc was also detected in the spleen of 22% of BASE-infected humanized mice, but not in those infected with sCJD. Secondary transmission of BASE in the humanized mice led to a small reduction in incubation time.
The atypical BSE-H strain is also transmissible with distinct phenotypes in the humanized mice, but no BSE-M transmission has been observed so far.
Discussion: Our results demonstrate that BASE is more virulent than classical BSE, has a lymphotropic phenotype, and displays a modest transmission barrier in our humanized mice.
BSE-H is also transmissible in our humanized Tg mice.
The possibility of more than two atypical BSE strains will be discussed.
Supported by NINDS NS052319, NIA AG14359, and NIH AI 77774.
Molecular Features of the Protease-resistant Prion Protein (PrPres) in H-type BSE
Biacabe, A-G1; Jacobs, JG2; Gavier-Widén, D3; Vulin, J1; Langeveld, JPM2; Baron, TGM1 1AFSSA, France; 2CIDC-Lelystad, Netherlands; 3SVA, Sweden
Western blot analyses of PrPres accumulating in the brain of BSE-infected cattle have demonstrated 3 different molecular phenotypes regarding to the apparent molecular masses and glycoform ratios of PrPres bands. We initially described isolates (H-type BSE) essentially characterized by higher PrPres molecular mass and decreased levels of the diglycosylated PrPres band, in contrast to the classical type of BSE. This type is also distinct from another BSE phenotype named L-type BSE, or also BASE (for Bovine Amyloid Spongiform Encephalopathy), mainly characterized by a low representation of the diglycosylated PrPres band as well as a lower PrPres molecular mass. Retrospective molecular studies in France of all available BSE cases older than 8 years old and of part of the other cases identified since the beginning of the exhaustive surveillance of the disease in 20001 allowed to identify 7 H-type BSE cases, among 594 BSE cases that could be classified as classical, L- or H-type BSE. By Western blot analysis of H-type PrPres, we described a remarkable specific feature with antibodies raised against the C-terminal region of PrP that demonstrated the existence of a more C-terminal cleaved form of PrPres (named PrPres#2 ), in addition to the usual PrPres form (PrPres #1). In the unglycosylated form, PrPres #2 migrates at about 14 kDa, compared to 20 kDa for PrPres #1. The proportion of the PrPres#2 in cattle seems to by higher compared to the PrPres#1. Furthermore another PK-resistant fragment at about 7 kDa was detected by some more N-terminal antibodies and presumed to be the result of cleavages of both N- and C-terminal parts of PrP. These singular features were maintained after transmission of the disease to C57Bl/6 mice. The identification of these two additional PrPres fragments (PrPres #2 and 7kDa band) reminds features reported respectively in sporadic Creutzfeldt-Jakob disease and in Gerstmann-Sträussler-Scheinker (GSS) syndrome in humans.
Saturday, December 01, 2007
Phenotypic Similarity of Transmissible Mink Encephalopathy in Cattle and L-type Bovine Spongiform Encephalopathy in a Mouse Model
Volume 13, Number 12–December 2007 Research
Friday, August 27, 2010
NEW ATYPICAL NOR-98 SCRAPIE CASE DETECTED IDAHO NOW 5 CASES DOCUMENTED 2010
Molecular characterization of BSE in Canada
Jianmin Yang1, Sandor Dudas2, Catherine Graham2, Markus Czub3, Tim McAllister1, Stefanie Czub1 1Agriculture and Agri-Food Canada Research Centre, Canada; 2National and OIE BSE Reference Laboratory, Canada; 3University of Calgary, Canada
Background: Three BSE types (classical and two atypical) have been identified on the basis of molecular characteristics of the misfolded protein associated with the disease. To date, each of these three types have been detected in Canadian cattle.
Objectives: This study was conducted to further characterize the 16 Canadian BSE cases based on the biochemical properties of there associated PrPres. Methods: Immuno-reactivity, molecular weight, glycoform profiles and relative proteinase K sensitivity of the PrPres from each of the 16 confirmed Canadian BSE cases was determined using modified Western blot analysis.
Results: Fourteen of the 16 Canadian BSE cases were C type, 1 was H type and 1 was L type. The Canadian H and L-type BSE cases exhibited size shifts and changes in glycosylation similar to other atypical BSE cases. PK digestion under mild and stringent conditions revealed a reduced protease resistance of the atypical cases compared to the C-type cases. N terminal- specific antibodies bound to PrPres from H type but not from C or L type. The C-terminal-specific antibodies resulted in a shift in the glycoform profile and detected a fourth band in the Canadian H-type BSE.
Discussion: The C, L and H type BSE cases in Canada exhibit molecular characteristics similar to those described for classical and atypical BSE cases from Europe and Japan. This supports the theory that the importation of BSE contaminated feedstuff is the source of C-type BSE in Canada. It also suggests a similar cause or source for atypical BSE in these countries.
Wednesday, August 11, 2010
REPORT ON THE INVESTIGATION OF THE SIXTEENTH CASE OF BOVINE SPONGIFORM ENCEPHALOPATHY (BSE) IN CANADA
Thursday, August 19, 2010
REPORT ON THE INVESTIGATION OF THE SEVENTEENTH CASE OF BOVINE SPONGIFORM ENCEPHALOPATHY (BSE) IN CANADA
Thursday, August 19, 2010
SCRAPIE CANADA UPDATE Current as of 2010-07-31 The following table lists sheep flocks and/or goat herds confirmed to be infected with scrapie in Canada in 2010.
Current as of: 2010-07-31