Problem: If a commensal microorganism breaches the epithelial barrier of the gut, which of the following does NOT occur?
a) The mucosal immune system ignores the beneficial microorganism, resulting in tolerance.
b) The mucosal immune system treats the invading microbe as a pathogen.
c) Dendritic cells present peptides from the commensal microbe and activate naive CD4 T cells.
d) B cells are activated and differentiate into plasma cells secreting antibodies specific for the commensal microbe.