Microbiology

Prions

A prion is a strange and sometimes deadly kind of protein. Dr. Stanley B. Prusiner of the University of California discovered it in 1982. He purified the infectious agent and named it “prion”, short for “proteinaceous infectious” particle. The normal prion protein is found throughout the body and brain. Even though it is not considered essential to life, it is believed that prion helps neurons in communicating and transporting minerals in the body.

Prions are natural produced in all mammals. However, they can be distorted in a way that makes them attack the body just like a virus attacks a tissue. The damage can even extend to the surrounding prions where the deformed prion causes the others to mimic its structure and malicious ways. Given that there is no way of stopping them, prions are considered very dangerous. Compared to viruses, they are even more mysterious. Antibiotics and radiation have no effect on them and there is no way of treating a patient who has been infected.

Prions cause a number of diseases in both animals and humans.

In animals, prions are believed to be the cause of the following:

* Scrapie in sheep and goats

* Bovine spongiform encephalopathy (BSE) in cattle ("mad cow disease")

* Transmissible mink encephalopathy (TME) in mink

* Chronic wasting disease (CWD) in North American cervids (mule deer, white-tailed deer, elk and moose)

* Feline spongiform encephalopathy in cats

* Exotic ungulate encephalopathy (EUE) in nyala, oryx and greater kudu

In humans:

* Sporadic forms:

* Sporadic Creutzfeldt-Jakob disease (sCJD)

* Sporadic Fatal Insomnia (sFI)

* Genetic forms:

* Familial Creutzfeldt-Jakob disease (fCJD)

* Gerstmann-Sträussler-Scheinker syndrome (GSS)

* Fatal Familial Insomnia (FFI)

* Acquired forms:

* Iatrogenic Creutzfeldt-Jakob disease (iCJD)

* Variant Creutzfeldt-Jakob disease (vCJD)

* Kuru