In vitro model for priocidal activity

Abstract

A proteinaceous material has been found to show similar activity and treatment response to that of disease causing prions, such as CJD. A prion model which incorporates the proteinaceous material has a variety of applications. The model has an ability to be cultured either in vivo or in vitro, allowing rapid screening of potential drugs for treating animals or humans, or methods of treating food products or items which may come into contact with prions, such as medical or dental devices. Several treatment methods and materials have been developed using the model.

Description

[0001] This Application claims the Priority of U.S. Provisional Application Ser. No. 60 / 327,460, filed Oct. 5, 2001.BACKGROUND OF THE INVENTION [0002] The present invention relates to the field of infectious diseases. It finds particular application as a method of evaluating the response of Prions (Proteinaceous Infectious Agents) to various treatments, and will be described with particular reference thereto. It should be appreciated, however, that the invention is also applicable to other studies of prion activity. [0003] The term “Prion” is used to describe proteinaceous-infectious agents that cause relatively similar brain diseases in humans and / or in animals, which are invariably fatal. These diseases are generally referred to as transmissible spongiform encephalopathies (TSEs). TSEs include Creutzfeldt-Jakob disease (CJD) and variant CJD (vCJD) in humans, Bovine Spongiform Encephalopathy (BSE) in cattle, also know as “Mad Cow Disease,” Scrapie in sheep, and Wasting Disease in e...

AI Technical Summary

Benefits of technology

[0019] One advantage of the present invention is that proposed prion disease treatments, pharmaceuticals, and priocidal agents can be screened in vitro, without the need for extensive in vivo study.

[0020] Another advantage of the present invention is that proposed prion disease treatments and priocidal agents can be evaluated rapidly.

[0021] Another advantage of the present invention is that prion-contaminated instruments, hard surfaces, and food products are rendered safer for use.

[0022] Still further advantages of the present invention will become apparent to those of ordinary skill in the art upon reading and understanding the following detailed description of the preferred embodiments.

Problems solved by technology

The abnormal form of the protein is not broken down effectively in the body and its accumulation in certain tissues (in particular neural tissue) eventually causes tissue damage, such as cell death.

There are currently no known effective treatments for prion diseases in animals or humans, and death thus follows the onset of neurological symptoms.

Progress in the identification of target treatment drugs has been slow, due to the inability to perform testing in vitro.

To date, no methods for culturing prions in media in the laboratory have been developed.

Because progress of the disease is slow, these in vivo studies are inevitably lengthy and are thus not readily amenable to the screening of large numbers of potential drugs.

In addition, because these diseases tend to be animal specific, it is not known whether tests done on animals can be readily applied to humans.

However, there have been no studies which have established correlations between the behavior of these proposed models and prion activity.

Prions are notoriously very hardy and demonstrate resistance to routine methods of decontamination and sterilization.

These aggressive treatments are often incompatible with medical devices, particularly flexible endoscopes and other devices with plastic, brass, or aluminum parts.

Many devices are damaged by exposure to high temperatures.

Chemical treatments, such as strong alkali, are damaging to medical device materials or surfaces in general.

However, there is currently no ready means of evaluating anti-prion (“priocidal”) treatments.

This is a lengthy process and prone to errors, since the numbers of prions remaining on the devices may be relatively small.

Additionally, there is a risk that prions which are not destroyed by the priocidal treatment may pose hazards to workers.

There are also concerns that the diseases may be transmitted, through reuse of instruments and the like, due to a failure to detect the disease state prior to death of the infected patient.

Additionally, the risks associated with high, medium, and low risk tissues have not yet been established.

However, recent evidence suggests the risks may higher, due to the finding that prion infected tissues are being found outside the brain.

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