Protocol for TRAUMADORNASE: a prospective, randomized, multicentre, double-blinded, placebo-controlled clinical trial of aerosolized dornase alfa to reduce the incidence of moderate-to-severe hypoxaemia in ventilated trauma patients

Identifying biomarkers deciphering sepsis from trauma-induced sterile inflammation and trauma-induced sepsis

Objective

The purpose of this study was to identify a panel of biomarkers for distinguishing early stage sepsis patients from non-infected trauma patients.

Background

Accurate differentiation between trauma-induced sterile inflammation and real infective sepsis poses a complex life-threatening medical challenge because of their common symptoms albeit diverging clinical implications, namely different therapies. The timely and accurate identification of sepsis in trauma patients is therefore vital to ensure prompt and tailored medical interventions (provision of adequate antimicrobial agents and if possible eradication of infective foci) that can ultimately lead to improved therapeutic management and patient outcome. The adequate withholding of antimicrobials in trauma patients without sepsis is also important in aspects of both patient and environmental perspective.

Methods

In this proof-of-concept study, we employed advanced technologies, including Matrix-Assisted Laser Desorption/Ionization (MALDI) and multiplex antibody arrays (MAA) to identify a panel of biomarkers distinguishing actual sepsis from trauma-induced sterile inflammation.

Results

By comparing patient groups (controls, infected and non-infected trauma and septic shock patients under mechanical ventilation) at different time points, we uncovered distinct protein patterns associated with early trauma-induced sterile inflammation on the one hand and sepsis on the other hand. SYT13 and IL1F10 emerged as potential early sepsis biomarkers, while reduced levels of A2M were indicative of both trauma-induced inflammation and sepsis conditions. Additionally, higher levels of TREM1 were associated at a later stage in trauma patients. Furthermore, enrichment analyses revealed differences in the inflammatory response between trauma-induced inflammation and sepsis, with proteins related to complement and coagulation cascades being elevated whereas proteins relevant to focal adhesion were diminished in sepsis.

Conclusions

Our findings, therefore, suggest that a combination of biomarkers is needed for the development of novel diagnostic approaches deciphering trauma-induced sterile inflammation from actual infective sepsis.

Neutrophil extracellular traps mediate deep vein thrombosis: from mechanism to therapy

Deep venous thrombosis (DVT) is a part of venous thromboembolism (VTE) that clinically manifests as swelling and pain in the lower limbs. The most serious clinical complication of DVT is pulmonary embolism (PE), which has a high mortality rate. To date, its underlying mechanisms are not fully understood, and patients usually present with clinical symptoms only after the formation of the thrombus. Thus, it is essential to understand the underlying mechanisms of deep vein thrombosis for an early diagnosis and treatment of DVT. In recent years, many studies have concluded that Neutrophil Extracellular Traps (NETs) are closely associated with DVT. These are released by neutrophils and, in addition to trapping pathogens, can mediate the formation of deep vein thrombi, thereby blocking blood vessels and leading to the development of disease. Therefore, this paper describes the occurrence and development of NETs and discusses the mechanism of action of NETs on deep vein thrombosis. It aims to provide a direction for improved diagnosis and treatment of deep vein thrombosis in the near future.

Early DNase-I therapy delays secondary brain damage after traumatic brain injury in adult mice

Traumatic brain injury (TBI) causes the release of danger-associated molecular patterns (DAMP) from damaged or dead cells, which contribute to secondary brain damage after TBI. Cell-free DNA (cfDNA) is a DAMP known to cause disruption of the blood-brain barrier (BBB), promote procoagulant processes, brain edema, and neuroinflammation. This study tested the hypothesis that administration of deoxyribonuclease-I (DNase-I) has a beneficial effect after TBI. Mice (n = 84) were subjected to controlled cortical impact (CCI) and posttraumatic intraperitoneal injections of low dose (LD) or high dose (HD) of DNase-I or vehicle solution at 30 min and 12 h after CCI. LD was most effective to reduce lesion volume (p = 0.003), brain water content (p < 0.0001) and to stabilize BBB integrity (p = 0.019) 1 day post-injury (dpi). At 6 h post injury LD-treated animals showed less cleavage of fibrin (p = 0.0014), and enhanced perfusion as assessed by micro-computer-tomography (p = 0.027). At 5 dpi the number of Iba1-positive cells (p = 0.037) were reduced, but the number of CD45-positive cells, motoric function and brain lesion volume was not different. Posttraumatic-treatment with DNase-I therefore stabilizes the BBB, reduces the formation of brain edema, immune response, and delays secondary brain damage. DNase-I might be a new approach to extend the treatment window after TBI.

Deciphering the role of damage-associated molecular patterns and inflammatory responses in acute lung injury

Acute lung injury (ALI) is characterized by diffuse pulmonary infiltrates and causes great mortality. ALI presents with overproduction of proinflammatory cytokines, cell death, destruction of alveoli-endothelial barriers, and neutrophil infiltration in lung tissues. Damage-associated molecular patterns (DAMPs) are molecules released from damaged cells due to infection, trauma, etc. DAMPs activate innate and adaptive immunity, trigger inflammatory responses, and are important in the initiation and development of ALI. We reviewed the literatures on DAMPs in ALI. Alveolar macrophages (AMs), neutrophils, and epithelial cells (AECs) are important in the pathogenesis of ALI. We comprehensively analyzed the interaction between DAMPs and AMs, alveolar neutrophils, and AECs. During the initial stage of ALI, ruptured cell membranes or destroyed mitochondria release DAMPs. DAMPs activate the inflammasome in nearby sentinel immune cells, such as AMs. AMs produce IL-1β and other cytokines. These mediators upregulate adhesion molecules of the capillary endothelium that facilitate neutrophil recruitment. The recruited neutrophils detect DAMPs using formyl peptide receptors on the membrane, guiding their migration to the injured site. The accumulation of immune cells, cytokines, chemokines, proteases, etc., results in diffuse alveolar damage and pulmonary hyperpermeability with protein-rich fluid retention. Some clinical studies have shown that patients with ALI with higher circulating DAMPs have higher mortality rates. In conclusion, DAMPs are important in the initiation and progression of ALI. The interactions between DAMPs and AMs, neutrophils, and AECs are important in ALI. This review comprehensively addresses the mechanisms of DAMPs and their interactions in ALI.

Multicenter analysis of neutrophil extracellular trap dysregulation in adult and pediatric COVID-19

Dysregulation in neutrophil extracellular trap (NET) formation and degradation may play a role in the pathogenesis and severity of COVID-19; however, its role in the pediatric manifestations of this disease, including multisystem inflammatory syndrome in children (MIS-C) and chilblain-like lesions (CLLs), otherwise known as “COVID toes,” remains unclear. Studying multinational cohorts, we found that, in CLLs, NETs were significantly increased in serum and skin. There was geographic variability in the prevalence of increased NETs in MIS-C, in association with disease severity. MIS-C and CLL serum samples displayed decreased NET degradation ability, in association with C1q and G-actin or anti-NET antibodies, respectively, but not with genetic variants of DNases. In adult COVID-19, persistent elevations in NETs after disease diagnosis were detected but did not occur in asymptomatic infection. COVID-19–affected adults displayed significant prevalence of impaired NET degradation, in association with anti-DNase1L3, G-actin, and specific disease manifestations, but not with genetic variants of DNases. NETs were detected in many organs of adult patients who died from COVID-19 complications. Infection with the Omicron variant was associated with decreased NET levels when compared with other SARS-CoV-2 strains. These data support a role for NETs in the pathogenesis and severity of COVID-19 in pediatric and adult patients.

Mucus Clearance Strategies in Mechanically Ventilated Patients

The use of airway clearance strategies as supplementary treatment in respiratory disease has been best investigated in patients with cystic fibrosis (CF) and non-cystic fibrosis bronchiectasis (NCFBE), conditions which are traditionally characterized by excessive mucus stasis and mucociliary dysfunction. A variety of airway clearance therapies both pharmacological and non-pharmacological have been shown to ameliorate disease progression in this population and have hence been assimilated into routine respiratory care. This self-propagating cycle of mucus retention and airway damage leading to chronic inflammation and infections can also be applied to patients with respiratory failure requiring mechanical ventilation. Furthermore, excessive trachea-bronchial secretions have been associated with extubation failure presenting an opportunity for intervention. Evidence for the use of adjunctive mucoactive agents and other therapies to facilitate secretion clearance in these patients are not well defined, and this subgroup still remains largely underrepresented in clinical trials. In this review, we discuss the role of mucus clearance techniques with a proven benefit in patients with CF and NCFBE, and their potential role in patients requiring mechanical ventilation while highlighting the need for standardization and adoption of mucus clearance strategies in these patient populations.

Elastase and exacerbation of neutrophil innate immunity are involved in multi-visceral manifestations of COVID-19

Background

Many arguments suggest that neutrophils could play a prominent role in COVID‐19. However, the role of key components of neutrophil innate immunity in severe forms of COVID‐19 has deserved insufficient attention. We aimed to evaluate the involvement of neutrophil elastase, histone‐DNA, and DNases in systemic and multi‐organ manifestations of COVID‐19.

Methods

We performed a multicenter study of markers of neutrophil innate immunity in 155 cases consecutively recruited in a screening center, local hospitals, and two regional university hospitals. The cases were evaluated according to clinical and biological markers of severity and multi‐organ manifestations and compared to 35 healthy controls.

Results

Blood neutrophil elastase, histone‐DNA, myeloperoxidase‐DNA, and free dsDNA were dramatically increased, and DNase activity was decreased by 10‐fold, compared with controls. Neutrophil elastase and histone‐DNA were associated with intensive care admission, body temperature, lung damage, and markers of cardiovascular outcomes, renal failure, and increased interleukin‐6 (IL‐6), IL‐8, and CXCR2. Neutrophil elastase was an independent predictor of the computed tomography score of COVID‐19 lung damage and the number of affected organs, in multivariate analyses. The increased blood concentrations of NE and neutrophil extracellular traps were related to exacerbation of neutrophil stimulation through IL‐8 and CXCR2 increased concentrations and increased serum DAMPs, and to impaired degradation of NETs as a consequence of the dramatic decrease in blood DNase activity.

Conclusion

Our results point out the key role of neutrophil innate immunity exacerbation in COVID‐19. Neutrophil elastase and DNase could be potential biomarkers and therapeutic targets of severe systemic manifestations of COVID‐19.

Ventilated Patients With COVID-19 Show Airflow Obstruction

Objective:

Many patients with coronavirus disease 2019 (COVID-19) need mechanical ventilation secondary to acute respiratory distress syndrome. Information on the respiratory system mechanical characteristics of this disease is limited. The aim of this study is to describe the respiratory system mechanical properties of ventilated COVID-19 patients.

Design, Setting, and Patients:

Patients consecutively admitted to the medical intensive care unit at the University of Iowa Hospitals and Clinics in Iowa City, USA, from April 19 to May 1, 2020, were prospectively studied; final date of follow-up was May 1, 2020.

Measurements:

At the time of first patient contact, ventilator information was collected including mode, settings, peak airway pressure, plateau pressure, and total positive end expiratory pressure. Indices of airflow resistance and respiratory system compliance were calculated and analyzed.

Main Results:

The mean age of the patients was 58 years. 6 out of 12 (50%) patients were female. Of the 21 laboratory-confirmed COVID-19 patients on invasive mechanical ventilation, 9 patients who were actively breathing on the ventilator were excluded. All the patients included were on volume-control mode. Mean [±standard deviation] ventilator indices were: resistive pressure 19 [±4] cmH₂O, airway resistance 20 [±4] cmH₂O/L/s, and respiratory system static compliance 39 [±16] ml/cmH₂O. These values are consistent with abnormally elevated resistance to airflow and reduced respiratory system compliance. Analysis of flow waveform graphics revealed a pattern consistent with airflow obstruction in all patients.

Conclusions:

Severe respiratory failure due to COVID-19 is regularly associated with airflow obstruction.

Use of dornase alfa in the paediatric intensive care unit: current literature and a national cross-sectional survey

Objectives

Airway mucus obstruction is a major challenge in children admitted to the paediatric intensive care unit (PICU). We aimed to evaluate the evidence and contemporary use of the mucolytic medication dornase alfa for non-cystic fibrosis conditions in the PICU.

Methods

(1) We performed a systematic review with searches in PubMed, EMBASE, and the Cochrane Library. Study selection: for quality assessment and data synthesis, we included only randomised controlled trials (RCTs) that compared dornase alfa to standard care or placebo in critically-ill paediatric patients (<18 years of age) in the PICU. However, non-randomised controlled studies and case series are also discussed. Data extraction: data were extracted independently by multiple reviewers using data extraction forms. The primary outcome was duration of mechanical ventilation. Data synthesis: The GRADE approach was used for quality assessment. No meta-analysis could be performed. (2) A national cross-sectional survey among all seven PICUs in the Netherlands was also performed.

Results

The systematic review yielded only one RCT, comparing dornase alfa with normal saline in children after cardiac surgery. In this study, dornase alfa led to a reduction in duration of mechanical ventilation by approximately 1 day (36% reduction). In addition, we found nine retrospective observational and case studies. The survey revealed high current use of dornase alfa in Dutch PICUs: 42% of the respondents reported prescribing dornase alfa at least once every week. Only 4% of the respondents reported having access to a local PICU dornase alfa protocol.

Conclusions

The off-label use of dornase alfa in the PICU is frequent without strong evidence or local protocols, highlighting the need for further research on the effectiveness of this mucolytic agent.

Current Status of COVID-19 Therapies and Drug Repositioning Applications

The rapid and global spread of a new human coronavirus (SARS-CoV-2) has produced an immediate urgency to discover promising targets for the treatment of COVID-19. Drug repositioning is an attractive approach that can facilitate the drug discovery process by repurposing existing pharmaceuticals to treat illnesses other than their primary indications. Here, we review current information concerning the global health issue of COVID-19 including promising approved drugs and ongoing clinical trials for prospective treatment options. In addition, we describe computational approaches to be used in drug repurposing and highlight examples of in silico studies of drug development efforts against SARS-CoV-2.

Consideration of dornase alfa for the treatment of severe COVID-19 acute respiratory distress syndrome

We propose a likely contribution to severe COVID-19 morbidity by extracellular DNA in neutrophil extracellular traps (NETs). Dornase alfa degrades extracellular DNA to reduce mucus rigidity and accumulation, and was associated with respiratory improvement in a first patient. Dornase alfa should be considered for clinical trials in treatment of severe COVID-19.