Related Experiment Video
Updated: Aug 8, 2026
Long-Term Catheterization of the Intestinal Lymph Trunk and Collection of Lymph in Neonatal Pigs
Published on: March 5, 2016
Identification and characterization of novel gut-associated lymphoid tissues in rat small intestine
Osamu Hitotsumatsu1, Hiromasa Hamada, Makoto Naganuma
1Department of Microbiology and Immunology, School of Medicine, Keio University, Tokyo, Japan.
Insights
Researchers discovered novel lymphocyte clusters, termed Lymphocyte-Filled Villi (LFVs), in the rat small intestine. These structures, similar to mouse cryptopatches, represent organized gut-associated lymphoid tissues in rats.
Area of Science:
- Immunology
- Gastrointestinal Biology
- Lymphoid Tissue Research
Background:
- Mouse small intestine harbors cryptopatches (CPs), containing c-kit+ and IL-7R+ lympho-hemopoietic cells.
- The presence of similar lymphoid tissues in other animal gastrointestinal tracts remains largely uninvestigated.
Purpose of the Study:
- To investigate the presence of lymphoid tissues analogous to mouse CPs in the rat small intestine.
Main Methods:
- Utilized immunohistochemical and flow cytometric analyses.
- Employed antibodies targeting c-kit and IL-7 receptor (IL-7R) molecules.
Main Results:
- Identified Lymphocyte-Filled Villi (LFVs) throughout the rat small intestine, characterized by c-kit+ and IL-7R+ cells.
- LFVs emerged around 2 weeks post-birth and contained immunoglobulin M-positive B cells, particularly in aged rats where germinal centers were observed.
- These findings represent the first description of isolated lymphoid follicles (ILFs) in the rat small intestine.
Conclusions:
- Provided the first evidence of c-kit+ and IL-7R+ lymphocyte clusters in the rat small intestine.
- LFVs and ILFs may represent novel organized gut-associated lymphoid tissues within the rat lamina propria.
Background:
The crypt lamina propria of the mouse small intestine has been shown to harbor multiple tiny clusters filled with c-kit- and interleukin 7 receptor (IL-7R)-positive lympho-hemopoietic cells (cryptopatches; CPs). However, it has remained an open question whether similar lymphoid tissue are present in the gastrointesitinal tract in other animals. In the present study, we investigated whether the small intestine of rats harbored lymphoid tissues similar to mouse CPs.
Methods:
Immunohistochemical and flow cytometric analyses were carried out using various antibodies, including those to c-kit and IL-7R molecules.
Results:
Lymphocyte-filled villi (LFVs), populated predominantly with c-kit- and IL-7 receptor (IL-7R)-positive cells and less with T cell receptor (TCR)-alphabeta T cells were found throughout the small intestine of young adult rats. Although LFVs were absent from fetal rat intestine, they were first detected at around 2 weeks after birth. Notably, in most LFVs that settled in the antimesenteric wall of the small intestine in young adult rats, immunoglobulin M-positive B cells were also detectable at the bottom of the LFVs. In aged rats, lymphocytes in some LFVs displayed a different phenotype, comprising a large B-cell area that included a germinal center. Thus, these clusters represent the first description of isolated lymphoid follicles (ILFs) in the rat small intestine.
Conclusions:
The present study provides the first evidence for c-kit- and IL-7R-positive lymphocyte clusters in the rat small intestine. Our data also indicating that LFVs and ILFs may constitute novel organized gut-associated lymphoid tissues in lamina propria of the rat small intestine.
Related Concept Videos
01:23Renewal of Intestinal Stem Cells
01:27Histology of the Small Intestine
The intestinal lining features transverse folds called circular folds, each housing fingerlike projections known as intestinal villi. These villi are covered by a layer of simple columnar epithelium, also referred to as...