Human CD14+ macrophages in intestinal lamina propria exhibit potent antigen-presenting ability.

Intestinal APCs are considered critical in maintaining the balance between the response against harmful pathogens and the induction of tolerance to commensal bacteria and food Ags. Recently, several studies indicated the presence of gut-specific APC subsets, which possess both macrophage and dendritic cell (DC) markers. These unique APC subsets play important roles in gut immunity, especially for immune regulation against commensal bacteria.