Proximity between 5-HT secreting enteroendocrine cells and lymphocytes in the gut mucosa of rhesus macaques (Macaca mulatta) is suggestive of a role for enterochromaffin cell 5-HT in mucosal immunity

J Neuroimmunol. 2004 Jan;146(1-2):46-9. doi: 10.1016/j.jneuroim.2003.10.044.


The involvement of serotonin (5-hydroxytryptamine; 5-HT) in immunoregulation has been well documented. Gut mucosa is a large reservoir of 5-HT most of which is attributed to gut endocrine cells. In this study, we examined the anatomical relationship among 5-HT immunoreactive cells and T and B lymphocytes in the gut mucosa of rhesus monkeys (Macaca mulatta). 5-HT, CD3 and CD20 immunoreactive cells were immunofluorescently labeled and visualized by confocal microscopy. 5-HT immunoreactive cells were primarily found within the epithelium of the intestine and were present at all levels of the gastrointestinal tract. Many 5-HT immunoreactive cells were in contact with, or very close proximity to CD3(+) and CD20(+) lymphocytes. These results provide morphological evidence to suggest interactions between 5-HT secreting enteroendocrine cells and lymphocytes in the gut mucosa. This further supports a possible role of 5-HT in mucosal immune responses.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Enterochromaffin Cells / chemistry
  • Enterochromaffin Cells / immunology
  • Enterochromaffin Cells / metabolism
  • Enteroendocrine Cells / chemistry
  • Enteroendocrine Cells / immunology*
  • Enteroendocrine Cells / metabolism*
  • Gastric Mucosa / chemistry
  • Gastric Mucosa / immunology*
  • Gastric Mucosa / metabolism
  • Immunity, Mucosal
  • Intestinal Mucosa / chemistry
  • Intestinal Mucosa / immunology*
  • Intestinal Mucosa / metabolism
  • Lymphocytes / chemistry
  • Lymphocytes / immunology*
  • Lymphocytes / metabolism
  • Macaca mulatta
  • Serotonin / metabolism*


  • Serotonin