VSIG4 inhibits the anti-inflammatory reaction of immune cells after cardiogenic shock

Abstract Cardiogenic shock (CS) still has a mortality rate of approximately 50%. CS leads to a significant activation of the immune system. The aim of this study was to characterize the immune cell populations and the immune cell-specific changes in CS on admission to the clinic and after revascularization. We developed a web-based platform named 'IRCaS - Immune Cell Regulations in Cardiogenic Shock' to map the temporal course of immune cell-specific processes of CS after acute myocardial infarction (AMI) from admission to 3 days after revascularization. Our tool revealed an endogenous anti-inflammatory response after CS, which is inhibited by the cell-cell receptor VSIG4. The web platform contains newly acquired single-cell sequencing data from patients with CS after AMI on admission and 24, 48, and 72 hours after revascularisation, as well as controls. In total, 171,962 immune cells derived from peripheral blood mononuclear cells (PBMCs) were individually sequenced. Analysis of the immune cell populations revealed, that 24 hours after revascularisation, monocytes increased to 62.4% (vs. 30.4% in controls), while T cells decreased from 46.3% to 25.0%. On the immune cell expression level, we observed an inflammatory response indicated by IL1B which continuously increased from 24 h (1.6+fold), over 48h (3.1+fold) to 72 h (3.5+fold) after revascularization. Interestingly, there was a significant anti-inflammatory response shortly after revascularization, as evidenced by a transient increase in the anti-inflammatory CD16+ monocyte subpopulation from 12.1% to 26.7% at 24 hours and an increase in THBS1 after revascularization, which was only short-lived. We identified a negative feedback in the increasing anti-inflammatory CD16+ cells caused by a subsequent VSIG4 (+5.2-fold) increase. Indeed, overexpression of VSIG4 in monocytes resulted in a significant decrease of anti-inflammatory CD16+ monocytes by 33.9% and a decrease in anti-inflammatory transcripts. Our data show that in addition to the strong inflammatory response in CS, there is also an opposing anti-inflammatory response, which is however only short-lived, as it is attenuated by a negative feedback via an increase in VSIG4. In addition, our webplatform offers time-dynamic gene expression profiles of immune cells, allowing users to select and visualize specific genes during the course of CS after AMI.