Which cytokine is primarily responsible for inducing class switching of B cells to produce IgE antibodies?

- The correct answer is IL-4 because it is the key cytokine that drives class switching to IgE in B cells.
- IL-4 activates the switch recombination mechanism in immunoglobulin genes, specifically promoting production of IgE antibodies, which are crucial in allergic responses.
- Neither IL-5, IFN-γ, nor TNF-α have this primary role in inducing IgE class switching. IL-4’s role is central in allergic immunity and parasite defense through IgE synthesis.

Reference: Janeway’s Immunobiology, 9th Edition, Chapter 6/ Page 245