Decrease of Membrane B7-H5 on CD14+ Cells in Severe Acute Pancreatitis Is Related to RANSON Scores and APACHE II Scores

Background B7-H5 is an important ligand which is deeply involved in the immune response in various diseases. However, its clinical usefulness as an early indicator in acute pancreatitis (AP) remains unclear. Aims To determine the role of B7-H5 in severe acute pancreatitis (SAP). Methods Whole blood samples from patients with SAP (n = 20) and healthy donors (n = 20) were collected. Expression of soluble B7-H5 (sB7-H5) in plasma was determined by ELISA and membrane B7-H5 (mB7-H5) on the peripheral CD14+ cells was determined by flow cytometry. Peripheral blood mononuclear cells (PBMCs) were isolated from healthy donors and stimulated with serum from SAP patients, lipopolysaccharide (LPS), TNF-α, or IFN-γ, then, sB7-H5 and mB7-H5 were measured. The relationship between expression levels of mB7-H5 and clinical features of SAP patients were analyzed. Results The expression levels of sB7-H5 in plasma were increased and the expression levels of mB7-H5 on the peripheral CD14+ cells were decreased in SAP patients. These changes of B7-H5 expression pattern in cultured PBMCs could be induced by stimulation with serum from SAP patients, LPS, TNF-α, or IFN-γ. Expression levels of mB7-H5 were negatively related to levels of hematocrit, urea nitrogen, creatinine, lactic acid, RANSON scores, and APACHE II scores. Conclusion Changes of B7-H5 expression pattern were involved in immune response of SAP. Innate immunity activation-induced decrease of mB7-H5 might be related to poor prognosis of SAP patients.