Biomarkers and immunomodulatory effect of erythropoietin in postoperative ileus.

Postoperative ileus (POI) is a type of intestinal motility disorder (IMD) that can occur after abdominal surgery. At present, there is no accepted treatment for POI and no reliable biomarkers to assess the status of POI. Erythropoietin (EPO) can promote the recovery of the intestine from various injuries, including POI. This study aimed to investigate the immunomodulatory role of EPO and to identify reliable biomarkers of POI. The computational analysis suggested that immune signaling via EPO/EPOR pathways may vary in POI. Luminex multiplex analysis showed that EPO treatment considerably altered intestinal tissue pro-inflammatory (CRP, IL6, IL12p70, IL12p40, IL2, and IFNγ) and anti-inflammatory (IL4, IL10, and IL13) cytokines. EPO decreased pro-inflammatory intestinal chemokines (CCL12, CXCL2, and CCL4) and serum IL6, CRP, and CCL12 following POI. IL6, CRP, and CCL12 may serve as promising biomarkers for POI in both tissue and serum samples. The gene expression analysis of these markers confirmed their significance with increased levels in intestinal tissue of POI, and EPO treatment caused attenuation. To our knowledge, this is the first study to investigate the immunomodulatory effect of EPO following IM, and suggests CCL12, CRP, and IL6 as reliable biomarkers of POI in both intestinal and serum samples.