The gut finds it a little tough to be immunized to bacterial or
viral infections since if they are, they will mount an attack at
almost any food that we eat which contains antigens. If this
happens, we'd end up starving coz we can't eat anything anymore as
the body is prepared to mount on anything we eat causing
inflammation of the gut and bloody diarrhoea.
That is why the gut only contains a group of antibodies, the IgA,
and not the others like the blood has... IgM, IgA, IgD, IgG and
IgE...
