A Scientist Reports the Isolation of a New Blood-Borne Virus

question 60

Multiple Choice

A scientist reports the isolation of a new blood-borne virus that completely shuts down presentation of viral epitopes on MHC molecules in the cells it infects. He produces an internet video describing the virus, claiming it will be indestructible by CD8+ cytotoxic T cells and will kill millions of people. The medical community quickly denounces the warning as irrelevant, and the whole thing is quickly forgotten. Why?

• A) CD8+ T cells are not the cells that are responsible for killing virally infected cells. The scientist has confused the information. The medical community denounces the information so that people are not unnecessarily alarmed by the video.
• B) While CD8+ T cells ARE important for eliminating a viral infection, they are not the ONLY things that can do so. Natural killer cells can kill virally infected cells that have shut down MHC antigen presentation, and interferons can assist in cleaning virally infected cells.
• C) A blood-borne virus would not be capable of rapidly infecting millions of people, due to its difficult mode of transmission AND CD8+ T cells are not the cells that are responsible for killing virally infected cells. The scientist has confused the information. The medical community denounces the information so that people are not unnecessarily alarmed.
• D) B cells would be primed right away to produce complement proteins to destroy the virus. This would prevent cells from being infected with it in the first place. The medical community denounces the scientist's video to prevent people from becoming alarmed.
• E) While CD8+ T cells ARE important for eliminating a viral infection, they are not the ONLY things that are capable of doing so. Natural killer cells can kill virally infected cells that have shut down MHC antigen presentation, and interferons can assist in cleaning virally infected cells AND a blood-borne virus would not be capable of rapidly infecting millions of people, due to its difficult mode of transmission.

---

Definitions:

Categorical Syllogism

A form of reasoning consisting of three statements - two premises followed by a conclusion, each statement categorically linking terms.

Conclusions

Statements or judgments that are arrived at after consideration of the evidence or arguments presented.

Premise

A premise is a statement or proposition from which another is inferred or follows as a conclusion.

Minor Term

In syllogistic logic, the term that appears in the conclusion and the minor premise but not in the major premise.