A prion is best described as what type of agent?

• A. A nucleic acid based infectious agent
• B. A protein particle that does not trigger an immune response
• C. A type of virus that is heat sensitive
• D. A common bacterial infection

Answer: (B)

A prion is best described as a protein particle that does not trigger an immune response. Unlike other infectious agents such as viruses or bacteria, prions are misfolded proteins that can induce normal proteins in the brain to also misfold, leading to devastating neurodegenerative diseases.

What distinguishes prions from other infectious agents is their unique composition, as they lack nucleic acids (DNA or RNA) and do not provoke the typical immune response seen with pathogens. This is significant because, in prion diseases, the body is unable to mount a defense against the misfolded proteins, which ultimately results in progressive damage to brain tissue. The lack of an immune response is one reason why prion-related diseases can be so difficult to treat and manage, as conventional immune-based therapies do not have the desired effect on these protein-based agents.