The most common indications for the use of probiotics are
the prevention or therapy of gastrointestinal disorders. The
mechanisms and the efficacy of their effects often depend on
interactions with the specific microflora of the host or immunocompetent
cells of the intestinal mucosa. This is connected
to the fact that the gut (or its associated lymphoid system, GALT)
is the largest immunologically competent organ in the human
body (de Vrese & Marteau, 2007; Eizaguirre et al., 2002).