What is the mechanism and a major adverse effect concern for monoclonal antibody therapies used in cancer or autoimmune diseases?

• A. Targeted immune modulation; adverse effects include infusion reactions and increased infection risk.
• B. Non-specific cytotoxicity; primary concern is liver toxicity.
• C. Broad immunosuppression with risk of severe infections.
• D. Inhibits bacterial cell wall synthesis.

Answer: (A)

Monoclonal antibodies work by selectively binding a specific target antigen to modulate immune responses or directly affect cancer cells, rather than delivering broad, non-specific cell killing. This targeted immune modulation is the mechanism highlighted here. The major safety concerns to watch are infusion reactions during administration and an increased risk of infections, stemming from altered or dampened immune function as these therapies exert their effects. Infusion reactions can occur due to cytokine release or hypersensitivity during the first exposures, while infection risk rises because some antibodies deplete certain immune cells or blunt inflammatory pathways, leaving patients more vulnerable. The other descriptions don’t fit how monoclonal antibodies act: non-specific cytotoxicity implies broad killing, broad immunosuppression resembles traditional immunosuppressants, and inhibiting bacterial cell wall synthesis is an antibiotic mechanism, not how these antibodies work.