Question

Consider a helminthic infection in which an individual is colonized by a parasitic worm. The worm is too big to be engulfed by a phagocytic cell. How does the immune system respond?

Answer 1

Answer

The worm gets coated with antibodies, which activate other cells in the immune system to secrete chemicals that kill it.

Explanation:

Production of T-helper I cytokines like IFN gamma, IL-2 and IL-18 is highly protective against helminth infection by activating the macrophage intracellular killers. Protection against mucosal eosinophil responses in which antiparasitic chemicals are released. Killing also involves direct cytotoxic mechanisms in which T- cell and NK-cells directly release antiparasitic agents like perforin and granulysin which kill the parasite.