Th9 and Th17 Cells in Human Ulcerative Colitis-Associated Dysplastic Lesions

Area of Science:

• Gastroenterology
• Immunology
• Oncology

Background:

• Inflammation drives colitis-associated colorectal cancer (CAC) development via a specific sequence.
• T helper (Th) subsets Th9 and Th17 cells are implicated in ulcerative colitis (UC) inflammation.
• Th9 and Th17 cells may promote colitis-associated dysplasia (CAD).

Purpose of the Study:

• To evaluate the presence and density of T lymphocytes, Th9, and Th17 cells in human UC and CAD tissues.
• To understand the role of Th9 and Th17 cells in the progression of UC to CAD and potentially CAC.

Main Methods:

• Immunohistochemistry (IHC) was used to analyze tissue samples.
• Quantified densities of CD3-positive T lymphocytes, P.U.1-positive Th9 cells, and IL-17A-positive Th17 cells.
• Compared cell densities across normal, UC, and CAD tissues, including dysplasia subgroups.

Main Results:

• T lymphocyte, Th9, and Th17 cell numbers generally increased from normal to UC to CAD tissues.
• These cells were prominent in the lamina propria and sometimes in the epithelium of CAD tissues.
• Th9 and Th17 cell densities were higher in CAD tissues compared to UC and control tissues, with slight differences between non-adenoma-like and adenoma-like dysplasia.

Conclusions:

• Accumulated Th9 and Th17 cells are part of the immune cellular makeup in CAD tissues.
• These cells may signify early changes facilitating the transition from dysplasia to CAC.
• Further research into Th9 and Th17 cell roles in CAC development is warranted.