Atmospheric pressure plasma promotes T lymphocytes activation.

T lymphocytes play a central role in the adaptive immune system, and the regulation of their activity is of critical importance. As an emerging therapeutic approach, accumulating evidence supports that atmospheric pressure plasma (APP) exerts anti-tumor effects by activating the immune function and inducing immunogenic cell death, thereby inhibiting tumor growth. However, it remains unclear whether APP has any effect on the activation of T cells. This study investigates the effect of APP on T cell activation and subset. We demonstrate that APP pretreatment increases both intracellular and extracellular reactive oxygen and nitrogen species (RONS) level in anti-CD3/28-stimulated Jurkat T cells, promoting proliferation, upregulating the activation markers CD69 and CD25, and enhancing the secretion of IL-2 and IFN-γ. Proteomic analysis revealed an activation of T cell receptor signaling pathway in the peripheral blood of rats after APP inhalation. Furthermore, flow cytometry demonstrated that APP inhalation increased the proportion of regulatory T cells in the peripheral blood of both normal rats and rats with cerebral ischemia, and ameliorated ischemic cerebral infarction. These findings suggest that APP can further activate T cells based on co-stimulatory signals, supporting its further investigation in immunomodulation.