Fibroblastic reticular cells and type 3 innate lymphoid cells in Peyer’s patches: Target cell candidates for inulooligosaccharides in hochuekkito formula containing Atractylodis rhizoma

Inulooligosaccharides in a Kampo formula, hochuekkito, have been shown to participate in the regulation of the pulmonary immune system. Difference in chain length distribution of the oligosaccharides strongly affects their immunopharmacological activities. This phenomenon cannot be explained by bifidogenic activity and/or short‐chain fatty acids produced by intestinal microflora from the oligosaccharides. Effects of intermediate‐size inulooligosaccharides, which have a similar chain length distribution as the oligosaccharides obtained from hochuekkito containing Atractylodis rhizoma, were analyzed on immunocompetent cells in Peyer’s patches.