Dynamics of Cytokine Capture Within Hemoadsorption Beads Used to Treat Sepsis

Sepsis is a serious medical condition characterized by systemic inflammation caused by infection, and affects more than 750,000 individuals per year in the US, with a mortality rate of approximately 30% [1]. The pathophysiology of sepsis is complex and not entirely understood, but is believed to be related to the dysfunction of multiple interdependent humoral mediator pathways, including redundant release of inflammatory cytokines [2]. Removal of both pro- and anti-inflammatory cytokines from the circulating blood is believed to be a promising therapy for severe sepsis [3]. We are developing an extracorporeal hemoadsorption device to remove cytokines from the blood using a novel, biocompatible, sorbent bead technology. A simple model was developed to characterize cytokine adsorption within hemoadsorption beads [4]. Despite rapid clearance of cytokines with hemoadsorption in an ex vivo murine sepsis model [5], our model analysis predicted that only the outer 20μm of each sorbent bead (avg diam = 450μm) adsorbed cytokine. In this work, we used in vitro column capture experiments and confocal laser scanning microscopy (CLSM) to examine cytokine adsorption dynamics within hemoadsorption beads.