Targeting neutrophils in inflammatory bowel disease: revisiting the role of adsorptive granulocyte and monocyte apheresis

Introduction Inflammatory bowel disease (IBD) is a chronic immune-mediated disease of the gastrointestinal tract comprising Crohn's disease (CD) and ulcerative colitis (UC). While any part of the digestive tract can be affected in CD, mucosal inflammation in UC is limited to the colon. Differences and similarities between the two conditions are reflected by their pathophysiology. Areas covered An overview of immunological aspects, pharmacological management, and biomarkers of IBD is provided. The role of adsorptive granulocyte and monocyte apheresis (GMA) is reviewed including its primary and secondary effects on the immune system, as well as clinical studies in IBD (mainly UC), and potential biomarkers for adsorptive GMA. Expert opinion In UC, adsorptive GMA with Adacolumn (Adacolumn (R), JIMRO Co., Ltd. Takasaki, Gunma, Japan) selectively depletes elevated myeloid lineage leukocytes and has a range of beneficial secondary immune effects. Adsorptive GMA is a safe and effective non-pharmacological treatment option for UC. Pilot studies have reported promising results for adsorptive GMA in combination with biological agents, although larger studies are required. Fecal calprotectin concentrations, neutrophil counts in histological samples and/or the neutrophil/lymphocyte ratio in peripheral blood may prove to be useful biomarkers for predicting GMA effectiveness in the future.

Automated summary

Inflammatory bowel disease (IBD) is a chronic immune-mediated disease that includes Crohn's disease (CD) and ulcerative colitis (UC). This article provides an overview of the immunological aspects, pharmacological management, and biomarkers of IBD. Adsorptive granulocyte and monocyte apheresis (GMA) with Adacolumn can effectively treat UC and has secondary immune effects. Fecal calprotectin concentrations, neutrophil counts in histological samples, and the neutrophil/lymphocyte ratio in peripheral blood may serve as useful biomarkers for predicting GMA effectiveness in the future.