CD28 and Sepsis: Following pathogen invasion, the expression of both CD28 + and CD45RA + was significantly upregulated, suggesting that co-expression of these markers on CD8 + T cells may play a role in the inflammatory response.[79,80] Based on this, our study hypothesized that CD8 + CD28 + CD45RA + CD8 + T cells may contribute to the pathogenesis and progression of sepsis through these mechanisms, suggesting that this subset of T cells could be a risk factor for sepsis.