Extracorporeal immune therapy with immobilized agonistic anti-Fas antibodies leads to transient reduction of circulating neutrophil numbers and limits tissue damage after hemorrhagic shock/resuscitation in a porcine model

Background: Hemorrhagic shock/resuscitation is associated with aberrant neutrophil activation and organ failure. This experimental porcine study was done to evaluate the effects of Fas-directed extracorporeal immune therapy with a leukocyte inhibition module (LIM) on hemodynamics, neutrophil tissue infiltration, and tissue damage after hemorrhagic shock/resuscitation. Methods: In a prospective controlled double-armed animal trial 24 Munich Mini Pigs (30.3 +/- 3.3 kg) were rapidly haemorrhaged to reach a mean arterial pressure (MAP) of 35 +/- 5 mmHg, maintained hypotensive for 45 minutes, and then were resuscitated with Ringer's solution to baseline MAP. With beginning of resuscitation 12 pigs underwent extracorporeal immune therapy for 3 hours (LIM group) and 12 pigs were resuscitated according to standard medical care (SMC). Haemodynamics, haematologic, metabolic, and organ specific damage parameters were monitored. Neutrophil infiltration was analyzed histologically after 48 and 72 hours. Lipid peroxidation, and apoptosis were specifically determined in lung, bowel, and liver. Results: In the LIM group, neutrophil counts were reduced versus SMC during extracorporeal immune therapy. After 72 hours, the haemodynamic parameters MAP and cardiac output (CO) were significantly better in the LIM group. Histological analyses showed reduction of shock-related neutrophil tissue infiltration in the LIM group, especially in the lungs. Lower amounts of apoptotic cells and lipid peroxidation were found in organs after LIM treatment. Conclusions: Transient Fas-directed extracorporeal immune therapy may protect from posthemorrhagic neutrophil tissue infiltration and tissue damage

Selection of proangiogenic ascorbate derivatives and their exploitation in a novel drug-releasing system for wound healing.

The pathophysiology leading to delayed wound healing is complex and efficient therapeutic approaches for accelerated wound healing currently do not exist. We developed a novel drug-eluting platform for the potential use in wound dressings. Here, we report on the potential of eluting ascorbic acid-2-phosphate (ASC-2P), a highly stable variant of ascorbic acid, to induce angiogenesis and to promote collagen synthesis by fibroblasts. The drug-eluting platform device (DEPD) consists of biocompatible polymeric layers comprising polyethylene terephtalate, polyvinyl alcohol (PVA), and polyurethane with PVA as the solvent for ASC-2P. The angiogenic potential of ASC-2P was evaluated in the endothelial cell tube formation assay (TFA) and in the chorion allantoic membrane (CAM) model. Collagen synthesis by ASC-2P-stimulated fibroblasts was determined by Sirius Red staining. ASC-2P significantly induced angiogenesis in five independent TFA and CAM assays and induced collagen synthesis in two different fibroblast cell lines. The eluting kinetics of ASC-2P was determined by the ultraviolet NanoDrop method and the functional 2,2'-Azinobis-(3-ethylbenzthiazolin-6-sulfonic acid) method. Eluting profiles showed a continuous release in the range of biologically effective concentrations >10 days. This is the first report showing the proangiogenic- and collagen-promoting features of ASC-2P. DEPD loaded with ASC-2P ought to be further evaluated as wound dressings or as supplementary pads for topical treatment of delayed wound healing in preclinical studies

Impaired cell viability and functionality of hepatocytes after incubation with septic plasma: Results of a second prospective biosensor study

Liver dysfunction (LD) and liver failure are associated with poor outcome in critically ill patients. In patients with severe sepsis or septic shock, LD occurred in nearly 19% of patients. An early diagnosis of LD at time of initial damage of the liver can lead to a better prognosis of these patients because an early start of therapy is possible. We performed a second prospective study with septic patients to test a new cell-based cytotoxicity device (biosensor) to evaluate clinical relevance for early diagnosis of LD and prognostic capacity. In the clinical study, 99 intensive care unit patients were included in two groups. From the patients of the septic group (n = 51, SG), and the control (non-septic) group [n = 49, control group (CG)] were drawn 20 ml blood at inclusion, after 3, and 7 days for testing with the biosensor. Patients’ data were recorded for hospital survival, organ function, and demographic data, illness severity [acute physiology and chronic health evaluation (APACHE) II-, sepsis-related organ failure assessment (SOFA) scores], cytokines, circulating-free deoxyribonucleic acid/neutrophil-derived extracellular traps (cf-DNA/NETs), microbiological results, and pre-morbidity. For the developed cytotoxicity test, the human liver cell line HepG2/C3A was used. Patients’ plasma was incubated in a microtiter plate assay with the test cells and after 6 days incubation the viability (trypan blue staining, XTT-test) and functionality (synthesis of albumin, cytochrome 1A2 activity) was analyzed. An impairment of viability and functionality of test cells was only seen in the SG compared with the CG. The plasma of non-survivors in the SG led to a more pronounced impairment of test cells than the plasma of survivors at inclusion. In addition, the levels of cf-DNA/NETs were significantly higher in the SG at inclusion, after 3, and after 7 days compared with the CG. The SG showed an in-hospital mortality of 24% and the values of bilirubin, APACHE II-, and SOFA scores were markedly higher at inclusion than in the CG. Hepatotoxicity of septic plasma was already detected with the liver cell-based biosensor at inclusion and also in the course of disease. The biosensor may be a tool for early diagnosis of LD in septic patients and may have prognostic relevance

Effects of bioreactor‐oxygenation during extracorporeal granulocytes treatment in septic patients

A granulocyte bioreactor for the extracorporeal treatment was developed to enhance the immune cell function in patients with severe sepsis. The influence of oxygenation on the used cells was tested in a prospective clinical study. Ten patients with severe sepsis were treated twice with the granulocyte bioreactor. The used cells were screened for functionality; values of blood gases, glucose and lactate were obtained from the recirculating bioreactor circuit. Five patients were treated with an oxygenator setup (Oxy group), five without oxygenator (Non-Oxy group). The overall in-hospital mortality was 50%. Significantly lower values of oxygen saturation, partial oxygen pressure, lactate, oxyburst and phagocytosis were seen in the Non-Oxy group compared with the Oxy group in the bioreactor circuit. Further studies with this approach are encouraged and should focus on the influence of oxygenation on production of reactive oxygen species and cytokines of used cells

Bioartificial Therapy of Sepsis: Changes of Norepinephrine-Dosage in Patients and Influence on Dynamic and Cell Based Liver Tests during Extracorporeal Treatments

Purpose. Granulocyte transfusions have been used to treat immune cell dysfunction in sepsis. A granulocyte bioreactor for the extracorporeal treatment of sepsis was tested in a prospective clinical study focusing on the dosage of norepinephrine in patients and influence on dynamic and cell based liver tests during extracorporeal therapies. Methods and Patients. Ten patients with severe sepsis were treated twice within 72 h with the system containing granulocytes from healthy donors. Survival, physiologic parameters, extended hemodynamic measurement, and the indocyanine green plasma disappearance rate (PDR) were monitored. Plasma of patients before and after extracorporeal treatments were tested with a cell based biosensor for analysis of hepatotoxicity. Results. The observed mortality rate was 50% during stay in hospital. During the treatments, the norepinephrine-dosage could be significantly reduced while mean arterial pressure was stable. In the cell based analysis of hepatotoxicity, the viability and function of sensor-cells increased significantly during extracorporeal treatment in all patients and the PDR-values increased significantly between day 1 and day 7 only in survivors. Conclusion. The extracorporeal treatment with donor granulocytes showed promising effects on dosage of norepinephrine in patients, liver cell function, and viability in a cell based biosensor. Further studies with this approach are encouraged