The ileum is the section of the small intestine that extends from the jejunum portion of the small intestine to the beginning of the large intestine (colon). It is about 12 feet (3.6m) long. The jejunum is a part of the small bowel, located between the end of duodenum and the proximal part of ileum. The duodenum is the first part of the small intestine. The adult small intestine is about 20 feet (6.0m) long, and the jejunum forms a little less than half of the small intestine. The transition from jejunum to ileum is not marked by any specific anatomic structure.
Antigen uptake of Beta Glucan occurs primarily in the ileum area through specialized cells called M cells (M = microfold). Overlying follicles that help grab key particles surround the dome shaped center of the M cells. M cells take up particulate through a mechanical process called pinocytosis (the uptake by a cell by invagination). This is a physical grabbing of the particles and pulling them through the lining of the intestinal wall. A large number of T cells, B cells, macrophages, and dendritic cells hover here and as the phagocytes engulf and digest antigen, they then present antigen markers to the T cells. It is remarkable that M cells will take soluble as well as particulate materials.
M cells also have the ability to take up entire bacterial pathogens such as salmonella, viruses,
Also found in this area are large amounts of antibodies (immunoglobulins - IgA & IgG). These antibodies are very important to helping deactivate bacterial toxins that interfere with phagocytosis (engulfing), chemotaxis (movement of immune cells), and other very important immune response activities.
To have a clear understanding of this area of the gut associated lymphoid tissue (GALT) is to appreciate one of the major ways that our immune system is kept aware of those things that are confronting us. This also leads us to understand why we advise that immune supplements such as beta glucan and aloe MPS be taken on an empty stomach. The M cells have the ability to identify, grab, and deliver into the lining of the intestinal wall solid particles as well as living pathogens. The size of these materials may be several microns in diameter and length.
Beta Glucan is best taken on an empty stomach if you wish to facilitate the highest levels of uptake per dose. Beta Glucan is primarily comprised on long chain polysaccharides and uptake for both would be similar.