Which vector is most likely to cause an immune response?

• A. Adeno-associated virus
• B. Retrovirus
• C. Adenovirus
• D. Naked DNA

Answer: (C)

The correct choice indicating that adenovirus is most likely to cause an immune response is due to its nature and the body's recognition of viral components. Adenoviruses are known to be relatively immunogenic because they are recognized by the immune system as foreign invaders. These viruses possess a robust structural protein composition that includes various antigens that can be detected by immune cells.

Upon introduction into the body, the immune system activates both the innate and adaptive immune responses. This activation includes the production of antibodies and the activation of cytotoxic T cells, which work to eliminate the virus. The pre-existing immunity that many individuals have against adenoviruses can also enhance this response, as many people have been exposed to adenoviruses in childhood, which leads to an enhanced immune reaction upon subsequent exposures.

In contrast, adeno-associated viruses tend to have a lower immunogenic profile, retroviruses can be either immunogenic or not depending on their specific variants, and naked DNA typically elicits a weaker immune response because it lacks the viral proteins that are recognized by immune cells. Thus, adenoviruses stand out as the most likely to provoke a significant immune response due to their effective evasion of immune detection and proliferation within host cells.