Published by Australian Academy of Science
Activity 6 | Prions – morphing agents of disease

Describing hypothetical experiments to determine infectiousness

1. Describe experiments that you would carry out to establish that nervous tissue taken from an animal with a spongiform encephalopathy was infectious to other individuals of the same species.

2. How could you assess if the nervous tissue would be infectious to humans?

Teachers notes

1. In discussing the transfer of nervous tissue from an infected animal to an uninfected one, students might consider how and when to look for symptoms in the recipient and any indication of susceptibility or resistance in the recipient. Scientific procedures should be described including the control of variables and replication.

2. The ethical constraints of experimentation on humans present a dilemma to all researchers. Human tissue culture cells can be used for research into human disease if the cell type and the agent can be grown in culture. Another avenue is for the research to be done on very closely related mammal species, such as chimpanzees. This is very expensive and has ethical constraints of its own. Mice are often used because of their size and relatively short life cycle. Recent genetic manipulation has produced mice that are more suitable for research into human diseases. For example, there are genetically engineered mice that have the human gene for the normal prion protein but not the mouse gene for it.