# T Helper and Cytotoxic T Cells Play an Important Role in Acute Gastric Injury

## TL;DR

This study shows that T helper and cytotoxic T cells contribute to acute stomach injury caused by ethanol, highlighting the role of cellular immunity in this process.

## Contribution

The study is the first to demonstrate the involvement of CD4+ and CD8+ T cells in ethanol-induced gastric injury.

## Key findings

- Ethanol exposure caused severe gastric injury and mucosal disruption in mice.
- CD4+ and CD8+ T cells, along with pro-inflammatory cytokines, were significantly increased in injured gastric tissue.
- Ethanol exposure also increased epithelial cell apoptosis, worsening mucosal damage.

## Abstract

Background: Inflammation plays a central role in the formation of peptic ulcers, yet the contribution of cellular immunity remains poorly defined. This study aimed to clarify the contribution of cellular immunity to acute gastric mucosal injury. Methods: BALB/c mice received 80% ethanol via oral gavage to induce acute gastric injury. Stomachs were examined macroscopically and histologically, and gastric tissues were analyzed by qPCR, ELISA, and flow cytometry for cytokine expression, immune cell infiltration, and apoptosis. Results: Administration of ethanol exacerbated acute gastric injury in mice, as evidenced by extensive macroscopic lesions and severe disruption of mucosal architecture. This damage was accompanied by marked infiltration of CD11c+ dendritic cells, together with an increased frequency of CD86-expressing and IL-12-producing dendritic cells. In addition, there was greater accumulation of both CD4+ and CD8+ T lymphocytes, including elevated numbers of CD4+ and CD8+ cells producing IFN-γ and IL-17, as well as CD8+CD107a+ cytotoxic cells. Alongside these cellular alterations, ethanol exposure was accompanied by elevated levels of pro-inflammatory cytokines (IL-1β, TNF-α, IL-17, and IFN-γ) in gastric tissue. In parallel, ethanol exposure also promoted epithelial cell apoptosis, further contributing to mucosal deterioration. Conclusions: Our findings reveal for the first time that both CD4+ and CD8+ T cells participate in sterile ethanol-induced acute gastric injury, emphasizing cellular immunity as an important yet insufficiently studied contributor to mucosal damage and highlighting the necessity for further mechanistic and translational research.