Related Experiment Video
Updated: Aug 26, 2026
Intravital Imaging of Intraepithelial Lymphocytes in Murine Small Intestine
Published on: June 24, 2019
Duodenal intraepithelial lymphocyte-count revisited
1Dept. of Pathology, University Hospital MAS, Malmö, Sweden. bela.veress@skane.se
Insights
The upper limit for duodenal intraepithelial lymphocytes (IELs) is redefined using CD3 staining, establishing a normal range of 25 IELs per 100 epithelial cells. This aids in diagnosing conditions like coeliac disease.
Area of Science:
- Gastroenterology
- Histopathology
- Immunology
Background:
- The established upper limit for duodenal intraepithelial lymphocytes (IELs) is over 30 years old.
- Previous normal upper limit for IELs was set at 40 lymphocytes per 100 epithelial cells.
Purpose of the Study:
- To establish a more accurate normal upper limit for duodenal intraepithelial lymphocytes (IELs).
- To differentiate normal IEL counts from those indicative of coeliac disease and other gastrointestinal conditions.
Main Methods:
- Analysis of duodenal biopsies from healthy individuals and patients with gastrointestinal symptoms.
- Staining of tissue sections with haematoxylin and eosin (H&E) and CD3.
- Counting of IELs per 100 epithelial cells and statistical analysis.
Main Results:
- Healthy individuals had a mean of 10.8 (H&E) and 13.2 (CD3) IELs/100 epithelial cells.
- The upper limit of the confidence interval for CD3 staining was 29 IELs/100 epithelial cells.
- No significant difference in IEL counts was observed between normal individuals and most clinical groups, except for active coeliac disease.
Conclusions:
- A two-step approach for IEL determination is proposed: semi-quantitative H&E and quantitative CD3 staining.
- The suggested upper normal limit for CD3+ IELs is 25 per 100 epithelial cells.
- Values between 25-29 are borderline, while 30+ indicate pathologic intraepithelial lymphocytosis.
Background:
The number of intraepithelial lymphocytes in the duodenum was determined 30 years ago, the suggested normal upper limit being 40 lymphocytes per 100 epithelial cells.
Methods:
Duodenal mucosa was analysed from 18 healthy individuals and 56 consecutive patients biopsied because of epigastralgia (17 cases), diarrhoea (10 cases), oesophagitis (10 cases), iron-deficiency (9 cases) and B12-deficiency (10 cases) showing normal histology, along with 10 cases of active coeliac disease. The biopsies were fixed in 4% formalin overnight and embedded in paraffin. Three micrometre thick sections were stained with haematoxylin and eosin and CD3. At least 300 epithelial cells were counted, the number of intraepithelial lymphocytes was given as the mean/100 epithelial cells. Extensive statistical analyses were performed.
Results:
In the healthy individuals the mean number (s) of intraepithelial lymphocytes/100 epithelial cells was 10.8 (2.6) and 13.2 (3.8) in H&E and CD3 stained sections, respectively. The upper limit of the confidence interval for CD3 staining was 29. There was no significant difference between normal individuals and the clinical groups, with the exception of coeliac disease.
Conclusion:
Two-step analysis of intraepithelial lymphocyte-determination is suggested: (a) semi-quantitative estimate on H&E-stained sections (normal ratio of 1:5 between lymphocytes and enterocytes; upper normal limit 20 lymphocytes) and (b) CD3-staining and counting if intraepithelial lymphocytosis is suspected. The upper normal range of intraepithelial lymphocytes is set at 25 CD3+ lymphocytes/100 epithelial cells. Values between 25 and 29 are regarded as 'borderline' and 30 or more represent pathologic intraepithelial lymphocytosis in the duodenum.
Related Concept Videos
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...
01:23Renewal of Intestinal Stem Cells