Myocardial dysfunction in sepsis has been linked to inflammation caused by pathogen-associated molecular patterns (PAMPs) as well as by host danger-associated molecular patterns (DAMPs). These ...include soluble heparan sulfate (HS), which triggers the devastating consequences of the pro-inflammatory cascades in severe sepsis and septic shock. Thus, there is increasing interest in the development of anti-infective agents, with effectiveness against both PAMPs and DAMPs. We hypothesized that a synthetic antimicrobial peptide (peptide 19-2.5) inhibits inflammatory response in murine cardiomyocytes (HL-1 cells) stimulated with PAMPs, DAMPs or serum from patients with septic shock by reduction and/or neutralization of soluble HS. In the current study, our data indicate that the treatment with peptide 19-2.5 decreases the inflammatory response in HL-1 cells stimulated with either PAMPs or DAMPs. Furthermore, our work shows that soluble HS in serum from patients with Gram-negative or Gram-positive septic shock induces a strong pro-inflammatory response in HL-1 cells, which can be effectively blocked by peptide 19-2.5. Based on these findings, peptide 19-2.5 is a novel anti-inflammatory agent interacting with both PAMPs and DAMPs, suggesting peptide 19-2.5 may have the potential for further development as a broad-spectrum anti-inflammatory agent in sepsis-induced myocardial inflammation and dysfunction.
Transpulmonary thermodilution is used to measure cardiac output (CO), global end-diastolic volume (GEDV) and extravascular lung water (EVLW). A system has been introduced (VolumeView/EV1000™ system, ...Edwards Lifesciences, Irvine CA, USA) that employs a novel algorithm for the mathematical analysis of the thermodilution curve. Our aim was to evaluate the agreement of this method with the established PiCCO™ method (Pulsion Medical Systems SE, Munich, Germany, clinicaltrials.gov identifier: NCT01405040) METHODS: Seventy-two critically ill patients with clinical indication for advanced hemodynamic monitoring were included in this prospective, multicenter, observational study. During a 72-hour observation period, 443 sets of thermodilution measurements were performed with the new system. These measurements were electronically recorded, converted into an analog resistance signal and then re-analyzed by a PiCCO2™ device (Pulsion Medical Systems SE).
For CO, GEDV, and EVLW, the systems showed a high correlation (r(2) = 0.981, 0.926 and 0.971, respectively), minimal bias (0.2 L/minute, 29.4 ml and 36.8 ml), and a low percentage error (9.7%, 11.5% and 12.2%). Changes in CO, GEDV and EVLW were tracked with a high concordance between the two systems, with a traditional concordance for CO, GEDV, and EVLW of 98.5%, 95.1%, and 97.7% and a polar plot concordance of 100%, 99.8% and 99.8% for CO, GEDV, and EVLW, respectively. Radial limits of agreement for CO, GEDV and EVLW were 0.31 ml/minute, 81 ml and 40 ml, respectively. The precision of GEDV measurements was significantly better using the VolumeView™ algorithm compared to the PiCCO™ algorithm (0.033 (0.03) versus 0.040 (0.03; median (interquartile range), P = 0.000049).
For CO, GEDV, and EVLW, the agreement of both the individual measurements as well as measurements of change showed the interchangeability of the two methods. For the VolumeView method, the higher precision may indicate a more robust GEDV algorithm.
clinicaltrials.gov NCT01405040.
SARS-CoV-2 infection results in varying disease severity, ranging from asymptomatic infection to severe illness. A detailed understanding of the immune response to SARS-CoV-2 is critical to unravel ...the causative factors underlying differences in disease severity and to develop optimal vaccines against new SARS-CoV-2 variants.
We combined single-cell RNA and T cell receptor sequencing with CITE-seq antibodies to characterize the CD8
T cell response to SARS-CoV-2 infection at high resolution and compared responses between mild and severe COVID-19.
We observed increased CD8
T cell exhaustion in severe SARS-CoV-2 infection and identified a population of NK-like, terminally differentiated CD8
effector T cells characterized by expression of
(encoding CD16). Further characterization of NK-like CD8
T cells revealed heterogeneity among CD16
NK-like CD8
T cells and profound differences in cytotoxicity, exhaustion, and NK-like differentiation between mild and severe disease conditions.
We propose a model in which differences in the surrounding inflammatory milieu lead to crucial differences in NK-like differentiation of CD8
effector T cells, ultimately resulting in the appearance of NK-like CD8
T cell populations of different functionality and pathogenicity. Our in-depth characterization of the CD8
T cell-mediated response to SARS-CoV-2 infection provides a basis for further investigation of the importance of NK-like CD8
T cells in COVID-19 severity.
In contrast to several smaller studies, which demonstrate that remote ischemic preconditioning (RIPC) reduces myocardial injury in patients that undergo cardiovascular surgery, the RIPHeart study ...failed to demonstrate beneficial effects of troponin release and clinical outcome in propofol-anesthetized cardiac surgery patients. Therefore, we addressed the potential biochemical mechanisms triggered by RIPC. This is a predefined prospective sub-analysis of the randomized and controlled RIPHeart study in cardiac surgery patients (
= 40) that was recently published. Blood samples were drawn from patients prior to surgery, after RIPC of four cycles of 5 min arm ischemia/5 min reperfusion (
= 19) and the sham (
= 21) procedure, after connection to cardiopulmonary bypass (CPB), at the end of surgery, 24 h postoperatively, and 48 h postoperatively for the measurement of troponin T, macrophage migration inhibitory factor (MIF), stromal cell-derived factor 1 (CXCL12), IL-6, CXCL8, and IL-10. After RIPC, right atrial tissue samples were taken for the measurement of extracellular-signal regulated kinase (ERK1/2), protein kinase B (AKT), Glycogen synthase kinase 3 (GSK-3β), protein kinase C (PKCε), and MIF content. RIPC did not significantly reduce the troponin release when compared with the sham procedure. MIF serum levels intraoperatively increased, peaking at intensive care unit (ICU) admission (with an increase of 48.04%,
= 0.164 in RIPC; and 69.64%,
= 0.023 over the baseline in the sham procedure), and decreased back to the baseline 24 h after surgery, with no differences between the groups. In the right atrial tissue, MIF content decreased after RIPC (1.040 ± 1.032 Arbitrary units au in RIPC vs. 2.028 ± 1.631 au in the sham procedure,
< 0.05). CXCL12 serum levels increased significantly over the baseline at the end of surgery, with no differences between the groups. ERK1/2, AKT, GSK-3β, and PKC
phosphorylation in the right atrial samples were no different between the groups. No difference was found in IL-6, CXCL8, and IL10 serum levels between the groups. In this cohort of cardiac surgery patients that received propofol anesthesia, we could not show a release of potential mediators of signaling, nor an effect on the inflammatory response, nor an activation of well-established protein kinases after RIPC. Based on these data, we cannot exclude that confounding factors, such as propofol, may have interfered with RIPC.
Sepsis is the most common cause of death in intensive care units and associated with widespread activation of host innate immunity responses. Ribonucleases (RNases) are important components of the ...innate immune system, however the role of RNases in sepsis has not been investigated. We evaluated serum levels of RNase 1, 3 and 7 in 20 surgical sepsis patients (Sepsis), nine surgical patients (Surgery) and 10 healthy controls (Healthy). RNase 1 and 3 were elevated in Sepsis compared to Surgery (2.2- and 3.1-fold, respectively; both p < 0.0001) or compared to Healthy (3.0- and 15.5-fold, respectively; both p < 0.0001). RNase 1 showed a high predictive value for the development of more than two organ failures (AUC 0.82, p = 0.01). Patients with renal dysfunction revealed higher RNase 1 levels than without renal dysfunction (p = 0.03). RNase 1 and 3 were higher in respiratory failure than without respiratory failure (p < 0.0001 and p = 0.02, respectively). RNase 7 was not detected in Healthy patients and only in two patients of Surgery, however RNase 7 was detected in 10 of 20 Sepsis patients. RNase 7 was higher in renal or metabolic failure than without failure (p = 0.04 and p = 0.02, respectively). In conclusion, RNase 1, 3 and 7 are secreted into serum under conditions with tissue injury, such as major surgery or sepsis. Thus, RNases might serve as laboratory parameters to diagnose and monitor organ failure in sepsis.
OBJECTIVE:To compare the effectiveness and safety of the hemoglobin-based nitric oxide scavenger, pyridoxalated hemoglobin polyoxyethylene, against placebo in patients with vasopressor-dependent ...distributive shock.
DESIGN:Multicenter, randomized, placebo-controlled, open-label study.
SETTING:Sixty-one participating ICUs in six European countries (Austria, Belgium, Germany, the Netherlands, Spain, and United Kingdom).
PATIENTS:All patients admitted with distributive shock, defined as the presence of at least two systemic inflammatory response syndrome criteria, persisting norepinephrine dependence and evidence of organ dysfunction/hypoperfusion despite adequate fluid resuscitation.
INTERVENTIONS:Patients were randomized to receive 0.25 mL/kg/hr pyridoxalated hemoglobin polyoxyethylene (20 mg Hb/kg/hr) or an equal volume of placebo, infused for up to 150 hours, in addition to conventional vasopressor therapy.
MEASUREMENTS AND MAIN RESULTS:The study was stopped after interim analysis showed higher mortality in the pyridoxalated hemoglobin polyoxyethylene group and an increased prevalence of adverse events. At this time, 377 patients had been randomized to pyridoxalated hemoglobin polyoxyethylene (n = 183) or placebo (n = 194). Age, gender, type of patient (medical/surgical), and Acute Physiology and Chronic Health Evaluation II scores were similar between groups. Twenty-eight–day mortality rate was 44.3% in the pyridoxalated hemoglobin polyoxyethylene group versus 37.6% in the placebo group (OR, 1.29; 95% CI, 0.85–1.95; p = 0.227). In patients with higher organ dysfunction scores (Sepsis-related Organ Failure Assessment > 13), mortality rates were significantly higher in the pyridoxalated hemoglobin polyoxyethylene group when compared with those in placebo-treated patients (60.9% vs 39.2%; p = 0.014). Survivors who received pyridoxalated hemoglobin polyoxyethylene had a longer vasopressor-free time (21.3 vs 19.7 d; p = 0.035).
CONCLUSIONS:In this randomized, controlled phase III trial in patients with vasopressor-dependent distributive shock, administration of a pyridoxalated hemoglobin solution decreased the need for vasopressors but was associated with a trend to increased mortality.
ABSTRACTThe heart is one of the most frequently affected organs in sepsis. Recent studies focused on lipopolysaccharide-induced mitochondrial dysfunction; however myocardial dysfunction is not ...restricted to gram-negative bacterial sepsis. The purpose of this study was to investigate circulating heparan sulfate (HS) as an endogenous danger associated molecule causing cardiac mitochondrial dysfunction in sepsis. We used an in vitro model with native sera (SsP) and sera eliminated from HS (HS-free), both of septic shock patients, to stimulate murine cardiomyocytes. As determined by extracellular flux analyzing, SsP increased basal mitochondrial respiration, but reduced maximum mitochondrial respiration, compared with unstimulated cells (P < 0.0001 and P < 0.0001, respectively). Cells stimulated with HS-free serum revealed unaltered basal and maximum mitochondrial respiration, compared with unstimulated cells (P = 0.1174 and P = 0.8992, respectively). Cellular ATP-level were decreased in SsP-stimulated cells but unaltered in cells stimulated with HS-free serum compared with unstimulated cells (P < 0.0001 and P = 0.1593, respectively). Live-cell imaging revealed an increased production of mitochondrial reactive oxygen species in cells stimulated with SsP compared with cells stimulated with HS-free serum (P < 0.0001). Expression of peroxisome proliferator-activated receptors (PPARα and PPARγ) and their co-activators PGC-1α, which regulate mitochondrial function, were studied using PCR. Cells stimulated with SsP showed downregulated PPARs and PGC-1α mRNA-levels compared with HS-free serum (P = 0.0082, P = 0.0128, and P = 0.0185, respectively). Blocking Toll-like receptor 4 revealed an inhibition of HS-dependent downregulation of PPARs and PGC-1α (all P < 0.0001). In conclusion, circulating HS in serum of septic shock patients cause cardiac mitochondrial dysfunction, suggesting that HS may be targets of therapeutics in septic cardiomyopathy.
Increasing rates of multi-resistant bacteria are a major problem in the treatment of critically ill patients. Furthermore, conventional antibiotics lead to the release of bacterial derived membrane ...parts initiating pro-inflammatory cascades with potential harm to the patient. Antimicrobial peptides (AMP) may kill bacteria without releasing pro-inflammatory factors. Thus, we compared three newly developed synthetic anti-lipopolysaccharide peptides (SALPs) with a broader range of efficacy to suppress cytokine release in plasma and CD14 mRNA expression in organ tissue in a murine, polymicrobial sepsis model.
A randomized, experimental trial was conducted in an animal research facility. Male NMRI mice (n = 90; 8- to 12-weeks old) were randomized to the following six groups: (i) sham operation and parenteral vehicle (NaCl 0.9%) administration (sham); (ii) cecal ligation and puncture (CLP) and vehicle infusion (sepsis-control), (iii) CLP and polymyxin B infusion (polyB), or (iv to vi) CLP and infusion of three different synthetic antimicrobial peptides Peptide 19-2.5 (Pep2.5), Peptide 19-4 (Pep4) or Peptide 19-8 (Pep8). All animals underwent arterial and venous catheterization for hemodynamic monitoring 48 hours prior to CLP or sham-operation. Physical appearance and behavior (activity), plasma cytokine levels, and CD14 mRNA expression in heart, lung, liver, spleen and kidney tissue were determined 24 hours after CLP or sham operation.
Only Pep2.5 significantly enhanced the activity after CLP, whereas none of the therapeutic regimens elevated the mean arterial pressure or heart rate. The strongly elevated IL-6, IL-10 and monocyte chemoattractant protein serum levels in septic animals were significantly reduced after Pep2.5 administration (P < 0.001, P < 0.001, and P < 0.001, respectively). Similarly, Pep2.5 significantly reduced the sepsis-induced CD14 mRNA expression in heart (P = 0.003), lung (P = 0.008), and spleen tissue (P = 0.009) but not in kidney and liver.
Structurally variable SALPs exhibit major differences in their anti-inflammatory effect in vivo. Continuous parenteral administration of Pep2.5 is able to reduce sepsis-induced cytokine release and tissue inflammation.
The aim of this study was to investigate (a) macrophage migration inhibitory factor (MIF) levels in polytrauma patients and rats after haemorrhagic shock (HS), (b) the potential of the MIF inhibitor ...ISO-1 to reduce multiple organ dysfunction syndrome (MODS) in acute (short-term and long-term follow-up) HS rat models and (c) whether treatment with ISO-1 attenuates NF-κB and NLRP3 activation in HS.
The MODS caused by an excessive systemic inflammatory response following trauma is associated with a high morbidity and mortality. MIF is a pleiotropic cytokine which can modulate the inflammatory response, however, its role in trauma is unknown.
The MIF levels in plasma of polytrauma patients and serum of rats with HS were measured by ELISA. Acute HS rat models were performed to determine the influence of ISO-1 on MODS. The activation of NF-κB and NLRP3 pathways were analysed by western blot in the kidney and liver.
We demonstrated that (a) MIF levels are increased in polytrauma patients on arrival to the emergency room and in rats after HS, (b) HS caused organ injury and/or dysfunction and hypotension (post-resuscitation) in rats, while (c) treatment of HS-rats with ISO-1 attenuated the organ injury and dysfunction in acute HS models and (d) reduced the activation of NF-κB and NLRP3 pathways in the kidney and liver.
Our results point to a role of MIF in the pathophysiology of trauma-induced organ injury and dysfunction and indicate that MIF inhibitors may be used as a potential therapeutic approach for MODS after trauma and/or haemorrhage.
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