Could we use PD-1 and PD-L1 expression on lymphocytes and monocytes as predictive markers for prognosis of acute biliary pancreatitis?

•PD-1 expression on CD4+ cells increase at pancreatitis and can be used as prognostic factors.•PD-L1 expression on CD14+ cells increase at pancreatitis and can be used as prognostic factors.•Intermediate monocyte ratios increase at pancreatitis and can be used as prognostic factors.•CD14+ HLA-DR+ cells and classical monocyte could also be used to predict organ failure. This study aimed to assess the significance of immunophenotyping and serum cytokines in predicting the clinical progression of acute biliary pancreatitis (ABP). Cytokine levels, T-helper, cytotoxic T, natural killer (NK) cells, monocytes, HLA-DR, and PD-1, as well as PDL-1 immune checkpoints, were measured in ABP patients at the time of diagnosis and compared with results from healthy volunteers. The study also compared leukocyte counts, hematocrit, immunophenotyping results, cytokine statuses, and PD-1, PDL-1 expression between healthy volunteers and ABP subgroups categorized by pancreatitis severity. The study included 65 ABP patients and 20 healthy volunteers. Significant differences were observed between groups in hematocrit, leukocyte counts, total monocytes, lymphocytes, CD3+ total T cells, CD4+ Th cells, PD-1 expression on CD4+ and CD8+T lymphocytes, HLA-DR expression on CD14+ monocytes, NK cells, PD-L1 expression on CD14+ monocytes, classical and intermediate monocytes, as well as levels of IL-6, IL-8, IL-10, IL-18, and IL-33 cytokines. Moderate correlations were found with lymphocyte counts, PD-1+CD4+ cells, PD-L1+CD14+ cells, and strong correlations with HLA-DR+CD14+ cells. Hematocrit, CD3+ total T cells, NK cells, CD4+PD-1 + T cells, and CD8+PD-1 + T cells showed independent associations with the severity of ABP. Lymphocyte counts, CD14+HLA-DR+ cells, CD14+PD-L1+ cells, CD4+PD-1 + T cells, classical, and intermediate monocytes exhibited the highest Area Under the Curve rates in determining organ failure. Hematocrit, lymphocyte counts, CD14+HLA-DR+ cells, CD14+PD-L1+ cells, and intermediate monocytes emerged as parameters most closely associated with the severity and these parameters could be useful in predicting the severity of ABP.