A.R. Scheirer, K.-G. Rueggeberg, T.D. Golobish, T. Guliashvili, M.C. Gruda, P. O’Sullivan, P.P. Chan
Keywords: sepsis, mycotoxins, fungal infection, extracorporeal hemoadsorption therapy, hemoperfusion, blood purification, porous polymer bead device, cytokines, pathogen-associated molecular pattern molecules, aspergillosis, aflatoxin
Summary:Opportunistic fungal infections account for up to 25% of all hospital-acquired blood infections. Patients at highest risk are those with weakened immune systems, and include elderly patients, patients with cancer or HIV infection, and patients taking immunosuppressive drugs due to chronic autoimmune disease or recent organ transplant. The production of poisonous toxins, such as aflatoxin and T2 toxin, partially explains the pathogenicity of these fungal infections. In addition, these toxins have been weaponized as biowarfare agents in the past. Mycotoxins are part of a broader class of toxins known as pathogen-associated molecular pattern molecules (PAMPs). PAMPs, which also include bacterial endotoxins and exotoxins, can either cause direct damage to tissues, or trigger a systemic inflammatory response syndrome (SIRS) in the host, driven by the production of high levels of cytokines and the release of damage-associated molecular pattern molecules (DAMPs). This milieu of circulating inflammatory mediators can subsequently induce a maladaptive SIRS response that can lead to multiple organ dysfunction syndrome (MODS), organ failure, and patient death. CytoSorb® (CytoSorbents Corporation, USA) is an extracorporeal hemoadsorption therapy that utilizes hemocompatible, highly porous polymer beads to reduce cytokines, toxins, PAMPs, DAMPs, and other inflammatory mediators in blood based on size and surface adsorption. Cytokine reduction has been correlated with improvement in survival and clinical outcomes in experimental studies and clinical reports using CytoSorb. CytoSorb removes aflatoxin from blood and, therefore, we postulate that CytoSorb will be effective against a broad range of mycotoxins. The purpose of this study was to further characterize the ability of CytoSorb to remove a broad range of PAMPs and cytokines in a single compartment, in vitro blood recirculation model, and investigate the potential ability of CytoSorb to remove T2 toxin by first evaluating the removal of a non-toxic surrogate from whole blood that can be safely tested in our laboratory. Purified proteins, or toxins, were added to whole bovine blood to achieve expected clinical concentrations. Blood was recirculated through a hemoperfusion device packed with CytoSorb® polymer beads for five hours. Plasma was analyzed using an enzyme-linked immunosorbent assay as per manufacturer instructions. The nontoxic surrogate molecule selected for T-2 toxin was epoxomicin, based on similarity of the chemical structures. Epoxomicin concentration was quantified from plasma using a kinetic, fluorogenic enzyme-based assay via 20S Proteosome inhibition. CytoSorb® polymer exhibited highly efficient removal of both aflatoxin and epoxomicin, reducing concentrations by more than 95% after 2 hours. Levels of toxic bacterial proteins and inflammatory cytokines in whole blood were also greatly reduced. This study demonstrates CytoSorb® hemoadsorbent polymer beads are capable of reducing clinically significant concentrations of mycotoxins and toxin surrogates from whole blood. The excellent capability of the adsorbent polymer beads to rapidly reduce aflatoxin and dangerous levels of pro-inflammatory cytokines supports the potential future novel clinical use of CytoSorb® to treat deadly fungal infections, such as Aspergillosis, and reduce the risk of SIRS and MODS, when used with standard of care therapy.