Resorption through the intestinal mucosa
Particles with a size of 0.1 until 5 microns (100 nm to 5 microns) are taken up by the cells of the intestinal villi (see figure on the left). At a particle size between 100 and 400 nm, about 85 % of the particles can be resorbed through the intestinal mucosa. This is reduced to approximately 30 % at a particle size of 5 microns. M cells of the Peyer's patches in the small intestine, specialised on the take-up of antigens, can resorb larger particles up to a size of about 10 microns. However, they represent only about 1 % of the absorptive surface of the small intestine.
Particles that are larger than 10 microns are no longer resorbed by the intestine. (For comparison, very fine sand grains have a size of about 60 microns.)
The proportion of APUXAN, which is not resorbed through the oral mucosa, passes into the gastrointestinal tract through swallowing. APUXAN is acid-resistant and indigestible and passes therefore safely through the stomach. In the small intestine, the particles can be easily resorbed through the intestinal epithelium and the M cells because of their small size of less than 400 nm. If taken up by M cells the particles directly reach into the Peyer's patches. These lymphoid organs of the digestive tract contain many immune cells that can be activated efficiently through the APUXAN particles.