Lymphatic tissue associated with the intestine is important for the early accumulation of prion protein and its subsequent spread to the central nervous system.
Transmissible prion diseases occur in both animals and man, two well-known ones being mad cow disease of cattle and Creutzfeldt Jacobs disease of man. These diseases produce symptoms in the central nervous system, with classical scrapie being characterised by intense itching with subsequent loss of wool, smacking of the lips, abnormal gait, and eventually collapse.
Protein molecules may show different properties when their structures become altered, for example, proteins in egg white are hardened by heat treatment. The assumed cause of prion diseases is that the structure of the normal prion protein (called PrPC) becomes altered. The abnormal, disease-associated form of the prion protein (called PrPSc) is assumed to be the infectious agent.
Infection most likely occurs across the intestine, and one first sees an accumulation of PrPSc in the lymphatic tissue associated with the intestine, especially in areas of the small intestine called Peyer's patches. The infection then spreads to the central nervous system and the brain, where, in the final stages of the disease, one sees an accumulation of PrPSc and also structural changes such as sponge-like "holes" in the brain mass.
We understand as yet very little of just how the infectious PrP is absorbed from the intestine. It is assumed that infection requires the presence of the normal form of the protein PrP, and it is known that the gene for PrP is active in a series of different types of cells and tissues.
For his doctorate, Lars Austbø investigated the activity of the gene for prion protein (PrP mRNA) by looking at where in the intestinal tissue it is formed and in what quantity. He also identified other genes of possible significance for the early phase of scrapie.
Austbø used advanced gene technology and molecular biology to study both prion gene activity (PrP mRNA) and the presence of the protein PrPC in the Payer's patches of the small intestine and in the spleen - two organs where lymphoreticular tissue is assumed to be important for the absorption of the infective substance (PrPSc) and its spread to the brain.
Austbø and his colleagues have compiled new knowledge of the tissues that the PrPC protein and its mRNA is expressed in and the degree to which the gene is active. In addition, the study has shown that accumulation of the disease-related prion protein (PrPSc) is not necessarily associated with high levels of the normal prion protein. This conflicts with earlier assumptions and may force a re-evaluation of earlier theories on the absorption and distribution of the disease-related prion protein.
In addition, Lars Austbø worked with the identification of other genes that may play a role in the development of scrapie. Many genes contribute to, or are affected by, any disease progression. By mapping such genes, one can gain a better impression of the processes that are initiated and thereby a better understanding of disease development.
Cand. scient. Lars Austbø defended his Ph. D. thesis, entitled "Studies on gene expression during the lymphoreticular phase of scrapie in sheep", on June 26, 2008. The work for the thesis was done at the Department of Basal Sciences and Aquatic Medicine, the Norwegian School of Veterinary Science.
Magnhild Jenssen | alfa
Further reports about: > Absorption > Accumulation > Creutzfeldt Jacobs disease > Intestinal lymphatic tissue > Lymphatic tissue > PrP > PrPSc > Prion > Scrapie > central nervous system > intestine > nervous system > prion protein > scrapie prion > transmissible, degenerative and ultimately fatal disease
Novel mechanisms of action discovered for the skin cancer medication Imiquimod
21.10.2016 | Technische Universität München
Second research flight into zero gravity
21.10.2016 | Universität Zürich
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.
In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...
'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.
Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
21.10.2016 | Health and Medicine
21.10.2016 | Information Technology
21.10.2016 | Materials Sciences