Question

Binding of which of the following antibody’s heavy chain initiates the lysis of bound bacterial cells?

(a) IgM

(b) IgD

(c) IgA

(d) IgE

This question was addressed to me in an interview for job.

This key question is from Molecular Basis of Immunity in chapter Immune Response of Cell Biology

Answer 1

Right choice is (a) IgM

To explain I would say: Binding of heavy chain of IgM leads to the activation of complement system that initiates the lysis of bacterial cells to which the antibody is bound. Similarly, binding of heavy chain of IgE initiates the allergic responses.