Intraepithelial lymphocytes in celiac disease

Area of Science:

• Gastroenterology
• Immunology
• Histopathology

Background:

• Celiac disease (CD) diagnosis can be challenging, necessitating refined diagnostic tools.
• Intraepithelial lymphocytes (IELs) play a role in the immune response within the small intestine.
• Understanding IEL subtypes may improve diagnostic accuracy for gastrointestinal disorders.

Purpose of the Study:

• To evaluate the utility of immunohistochemical staining for different IEL subtypes in diagnosing celiac disease.
• To assess the diagnostic performance (sensitivity and specificity) of CD3+, alphabeta+, and gammadelta+ IELs.
• To correlate IEL counts with mucosal morphology and response to a gluten-free diet.

Main Methods:

• A cohort of 928 adult patients suspected of having CD or being monitored for dietary compliance underwent endoscopy.
• A control group of 59 adults with indigestion also underwent endoscopy.
• Small bowel mucosal morphology and IEL populations (CD3+, alphabeta+, gammadelta+) were analyzed.

Main Results:

• CD3+ and gammadelta+ IELs demonstrated high sensitivity (93%) for CD diagnosis.
• gammadelta+ IELs showed superior specificity (88%) compared to CD3+ (73%) and alphabeta+ (66%) IELs.
• Gluten-free diet led to mucosal recovery and decreased IEL densities, though gammadelta+ IELs remained elevated versus controls.

Conclusions:

• Counting IELs, particularly gammadelta+ cells, is valuable in borderline or histologically ambiguous celiac disease cases.
• Increased gammadelta+ IELs significantly strengthen the suspicion of celiac disease.
• While informative, increased IELs are not universally present in all celiac disease patients.