Microfold (M) cells are a kind of intestinal epithelial cell in the follicle-associated epithelium (FAE) of Peyer’s patches. They can transport antigens and microorganisms to lymphoid tissues. Bovine spongiform encep...Microfold (M) cells are a kind of intestinal epithelial cell in the follicle-associated epithelium (FAE) of Peyer’s patches. They can transport antigens and microorganisms to lymphoid tissues. Bovine spongiform encephalopathy (BSE) is a fatal neurodegenerative disorder in cattle. It is linked to variant Creutzfeldt-Jakob disease in humans. Although it is thought that M cells transport the BSE agent, the exact mechanism by which it crosses the intestinal barrier is not clear. We have bovine intestinal epithelial cell line (BIE cells), which can differentiate into the M cell type in vitro after stimulation, and which is able to transport the BSE agent. We show here that M cells are able to incorporate large numbers of PrP coated magnetic particles into intracellular vesicles, which we collected. The results of 2-DE show a specific protein associated with the PrP-coated particles, compared with non-coated particles. This protein was identified as aldolase A, a glycolytic pathway enzyme, using LC-MS/MS analysis. Aldolase A was synthesized and secreted by BIE cells, and increased during M cell differentiation. In the villi of the bovine intestine, aldolase A was detected on the surface of the epithelium and in the mucus droplet of goblet cells. In the FAE of bovine jejunal and ileal Peyer’s patches, aldolase A was localized on the surface and the apical part of the M cells. The binding of rbPrP to aldolase A was clearly detected and inhibited by pre-treatment of anti-aldolase A antibody. Aldolase A was co-stained with incorporated PrPSc in M-BIE cells. These results suggest that bovine M cells and goblet cells synthesize aldolase A, and that aldolase A may have the ability to bind PrP and associate with PrP in cellular vesicles. Therefore, aldolase A-positive M cells may play a key role in the invasion of BSE into the body.展开更多
The rapid detection of infectivity of several agents that cause Creutzfeldt-Jakob disease has previously been achieved by assaying for deposits of abnormal prion protein (PrPSc) in follicular dendritic cells in the sp...The rapid detection of infectivity of several agents that cause Creutzfeldt-Jakob disease has previously been achieved by assaying for deposits of abnormal prion protein (PrPSc) in follicular dendritic cells in the spleens of transgenic mice carrying the human prion protein gene. In this study, transgenic mice expressing the bovine prion protein were inoculated intraperitoneally with classical (C-type) or atypical L-type bovine spongiform encephalopathies (BSE). Proteinase-resistant PrPSc were detected in the spleens of all transgenic mice at 75 days after inoculation with both types of BSE. Infectivity in PrPSc-positive spleens of the transgenic mice revealed that prions of C- and L-type BSE replicated. These results suggest that bioassay system by the transgenic mice could be useful for the rapid detection of BSE infectivity with discriminating between C- and L-type BSEs.展开更多
文摘Microfold (M) cells are a kind of intestinal epithelial cell in the follicle-associated epithelium (FAE) of Peyer’s patches. They can transport antigens and microorganisms to lymphoid tissues. Bovine spongiform encephalopathy (BSE) is a fatal neurodegenerative disorder in cattle. It is linked to variant Creutzfeldt-Jakob disease in humans. Although it is thought that M cells transport the BSE agent, the exact mechanism by which it crosses the intestinal barrier is not clear. We have bovine intestinal epithelial cell line (BIE cells), which can differentiate into the M cell type in vitro after stimulation, and which is able to transport the BSE agent. We show here that M cells are able to incorporate large numbers of PrP coated magnetic particles into intracellular vesicles, which we collected. The results of 2-DE show a specific protein associated with the PrP-coated particles, compared with non-coated particles. This protein was identified as aldolase A, a glycolytic pathway enzyme, using LC-MS/MS analysis. Aldolase A was synthesized and secreted by BIE cells, and increased during M cell differentiation. In the villi of the bovine intestine, aldolase A was detected on the surface of the epithelium and in the mucus droplet of goblet cells. In the FAE of bovine jejunal and ileal Peyer’s patches, aldolase A was localized on the surface and the apical part of the M cells. The binding of rbPrP to aldolase A was clearly detected and inhibited by pre-treatment of anti-aldolase A antibody. Aldolase A was co-stained with incorporated PrPSc in M-BIE cells. These results suggest that bovine M cells and goblet cells synthesize aldolase A, and that aldolase A may have the ability to bind PrP and associate with PrP in cellular vesicles. Therefore, aldolase A-positive M cells may play a key role in the invasion of BSE into the body.
文摘The rapid detection of infectivity of several agents that cause Creutzfeldt-Jakob disease has previously been achieved by assaying for deposits of abnormal prion protein (PrPSc) in follicular dendritic cells in the spleens of transgenic mice carrying the human prion protein gene. In this study, transgenic mice expressing the bovine prion protein were inoculated intraperitoneally with classical (C-type) or atypical L-type bovine spongiform encephalopathies (BSE). Proteinase-resistant PrPSc were detected in the spleens of all transgenic mice at 75 days after inoculation with both types of BSE. Infectivity in PrPSc-positive spleens of the transgenic mice revealed that prions of C- and L-type BSE replicated. These results suggest that bioassay system by the transgenic mice could be useful for the rapid detection of BSE infectivity with discriminating between C- and L-type BSEs.
