Foxp3 expression patterns in microscopic colitides: a clinicopathologic study of 69 patients

Area of Science:

• Gastroenterology
• Immunology
• Pathology

Background:

• Microscopic colitides, including lymphocytic colitis (LC) and collagenous colitis (CC), involve immune dysregulation.
• CD8+ T lymphocytes (CTLs) and regulatory T cells (Tregs) play a role in immune responses, with Foxp3 being a key regulator in Tregs.

Purpose of the Study:

• To investigate and compare the distribution patterns of Foxp3+ Tregs and CTLs in colonic biopsy specimens from patients with LC and CC.
• To explore the correlation between immune cell distribution and the distinct morphologic features of these microscopic colitides.

Main Methods:

• Analysis of 71 colonic biopsy specimens from 69 patients diagnosed with no significant histopathologic abnormality (NSHPA), LC, or CC.
• Immunohistochemical evaluation using markers for CD8 (CTLs) and Foxp3 (Tregs).

Main Results:

• Significant differences were observed in the distribution patterns of CTLs between LC and CC.
• Distinct immunologic recruitment patterns of Foxp3+ Tregs in the colonic mucosa were identified for LC and CC.
• These immune cell distribution differences correlate with the spectrum of morphologic changes in each condition.

Conclusions:

• The study highlights specific differences in immune cell infiltration in LC and CC.
• Foxp3+ Treg distribution patterns are associated with the distinct histopathologic features of lymphocytic colitis and collagenous colitis.
• Understanding these immune differences may offer insights into the pathogenesis and potential therapeutic targets for microscopic colitides.