In schistosome immunity, the interaction described involves intact worms evading immune responses and eggs being attacked. Which option captures this interaction?

• A. Intact worms evade immune responses; eggs are attacked.
• B. Eggs evade immune responses; worms are attacked.
• C. Larvae evade immune responses; eggs are attacked.
• D. Eggs are unaffected by immune responses.

Answer: (A)

Schistosome immunity shows stage-specific immune interactions: adult worms evade immune detection, while the eggs they lay provoked a strong immune attack. The worm’s surface, or tegument, can cloak parasite antigens and modulate host responses, helping the adult worms circulate in the bloodstream with little disruption. In contrast, eggs are highly antigenic and become coated with host immune components; the body mounts a vigorous response to these eggs, leading to granuloma formation and tissue inflammation. So the scenario that best fits this pattern is intact worms avoiding immune responses while eggs are attacked.