EVALUATION OF CYFRA 21-1, ANGIOPOETIN-2, PENTRAXIN-3, SRAGE, IL-6, AND IL-10 IN POLYTRAUMATIZED PATIENTS WITH CONCOMITANT THORACIC TRAUMA-HELPFUL MARKERS TO PREDICT PNEUMONIA?

ABSTRACT: Background: Pneumonia is a frequent complication after polytrauma. This study aims to evaluate the ability of different serum markers to identify patients at risk of developing pneumonia after polytrauma. Methods: A retrospective analysis of prospectively collected data in polytraumatized patients with concomitant thoracic trauma (Injury Severity Score ≥16, Abbreviated Injury Scale Thorax ≥ 3) was performed. The study cohort was divided into patients with and without pneumonia during the clinical course. Serum levels of lung epithelial (CYFRA 21-1), endothelial (Ang-2), and inflammatory (PTX-3, sRAGE, IL-6, IL-10) markers were measured upon arrival in the trauma room and on days 2 and 5. Results: A total of 73 patients and 16 healthy controls were included in this study. Of these, 20 patients (27.4%) developed pneumonia. Polytraumatized patients showed significantly increased CYFRA 21-1 levels with a distinct peak after admission compared with healthy controls. Serum PTX-3 significantly increased on day 2 in polytraumatized patients compared with healthy controls. Injury Severity Score and demographic parameters were comparable between both groups (pneumonia vs. no pneumonia). No statistically significant difference could be observed for serum levels of CYFRA 21-1, Ang-2, PTX-3, sRAGE, IL-6, and IL-10 between the groups (pneumonia vs. no pneumonia) on all days. Logistic regression revealed a combination of IL-6, IL-10, sRAGE, and PTX-3 to be eventually helpful to identify patients at risk of developing pneumonia and our newly developed score was significantly higher on day 0 in patients developing pneumonia ( P < 0.05). Conclusion: The investigated serum markers alone are not helpful to identify polytraumatized patients at risk of developing pneumonia, while a combination of IL-6, IL-10, PTX-3, and sRAGE might be.

[Costs-revenue deficit of outpatient treatment of minor injuries in the emergency department]. / Kosten-Erlös-Defizit der ambulanten Versorgung von Bagatellverletzungen in der Notaufnahme.

BACKGROUND: Many patients with minor injuries hastily present in the emergency department and tie up resources and personnel there. OBJECTIVE: To establish the cost-revenue relationship of outpatient care of minor injuries in the traumatology emergency department. MATERIAL AND METHODS: The calculation was based on the uniformly billed emergency flat rates of the uniform assessment standard (EBM). Using the current collective bargaining agreements for physicians and nurses, per minute costs were calculated. The time required for treatment was determined on the basis of 100 reference patients with minor injuries. The case cost calculation with the respective resources was carried out with the operational controlling of the University Hospital Frankfurt. RESULTS: A total of 4088 patients with minor injuries who presented in 2019 were included. Most common reasons for presentation were contusions of the lower (31.9%; n = 1303) and upper extremities (16.6%; n = 677). A time expenditure of 166.7 min per day for the medical staff and 213.8 min per day for nursing staff was calculated. A total revenue of 29,384.31 € and total costs of 69,591.22 € were calculated. Thus, a revenue deficit of -40,206.91 € can be calculated for the year 2019. This corresponds to a monetary deficit of 9.84 € per patient. CONCLUSION: There is a shortage of the medical resource "personnel" to satisfactorily and economically manage the nowadays high volume of self-presenting pedestrian patients with minor injuries. The current remuneration of the treatment of minor injuries by the uniform assessment scale is insufficient for the hospital sector.

I-FABP as a Potential Marker for Intestinal Barrier Loss in Porcine Polytrauma.

Polytrauma and concomitant hemorrhagic shock can lead to intestinal damage and subsequent multiple organ dysfunction syndrome. The intestinal fatty acid-binding protein (I-FABP) is expressed in the intestine and appears quickly in the circulation after intestinal epithelial cell damage. This porcine animal study investigates the I-FABP dynamics in plasma and urine after polytrauma. Furthermore, it evaluates to what extent I-FABP can also act as a marker of intestinal damage in a porcine polytrauma model. Eight pigs (Sus scrofa) were subjected to polytrauma which consisted of lung contusion, tibial fracture, liver laceration, and hemorrhagic shock followed by blood and fluid resuscitation and fracture fixation with an external fixator. Eight sham animals were identically instrumented but not injured. Afterwards, intensive care treatment including mechanical ventilation for 72 h followed. I-FABP levels in blood and urine were determined by ELISA. In addition, immunohistological staining for I-FABP, active caspase-3 and myeloperoxidase were performed after 72 h. Plasma and urine I-FABP levels were significantly increased shortly after trauma. I-FABP expression in intestinal tissue showed significantly lower expression in polytraumatized animals vs. sham. Caspase-3 and myeloperoxidase expression in the immunohistological examination were significantly higher in the jejunum and ileum of polytraumatized animals compared to sham animals. This study confirms a loss of intestinal barrier after polytrauma which is indicated by increased I-FABP levels in plasma and urine as well as decreased I-FABP levels in immunohistological staining of the intestine.

Club cell protein (CC)16 as potential lung injury marker in a porcine 72 h polytrauma model.

BACKGROUND: Polytrauma and respiratory tract damage after thoracic trauma cause about 25% of mortality among severely injured patients. Thoracic trauma can lead to the development of severe lung complications such as acute respiratory distress syndrome, and is, therefore, of great interest for monitoring in intensive care units (ICU). In recent years, club cell protein (CC)16 with its antioxidant properties has proven to be a potential outcome-related marker. In this study, we evaluated whether CC16 constitutes as a marker of lung damage in a porcine polytrauma model. METHODS: In a 72 h ICU polytrauma pig model (thoracic trauma, tibial fracture, hemorrhagic shock, liver laceration), blood plasma samples (0, 3, 9, 24, 48, 72 h), BAL samples (72 h) and lung tissue (72 h) were collected. The trauma group (PT) was compared to a sham group. CC16 as a possible biomarker for lung injury in this model, and IL-8 concentrations as known indicator for ongoing inflammation during trauma were determined by ELISA. Histological analysis of ZO-1 and determination of total protein content were used to show barrier disruption and edema formation in lung tissue from the trauma group. RESULTS: Systemic CC16 levels were significantly increased early after polytrauma compared vs. sham. After 72 h, CC16 concentration was significantly increased in lung tissue as well as in BAL in PT vs. sham. Similarly, IL-8 and total protein content in BAL were significantly increased in PT vs. sham. Evaluation of ZO-1 staining showed significantly lower signal intensity for polytrauma. CONCLUSION: The data confirm for the first time in a larger animal polytrauma model that lung damage was indicated by systemic and/or local CC16 response. Thus, early plasma and late BAL CC16 levels might be suitable to be used as markers of lung injury in this polytrauma model.

Acetabular fractures treatment needs in the elderly and nonagenarians.

Different treatment options for acetabular fractures in the elderly and nonagenarians exist; a consistent guideline has not been established, yet. The purpose of this study is to give an overview of how those fractures can be handled and compares two different surgical treatment methods. A total of 89 patients ≥ 18 years between 2016 and 2021 with acetabular fractures in our department received a surgical intervention with plate fixation via the Stoppa approach or a total hip arthroplasty with a Burch-Schneider ring and integrated cup. 60 patients ≥ 65 were compared in two groups, 29 patients between 65 and 79 and 31 patients ≥ 80. For comparison, data on operation times, hospitalization, complications during operation and hospital stay, blood loss and postoperative mobilization were collected. Characteristics could be found for indications for operative osteosynthesis or endoprosthetics based on the X-ray analysis. There was a tendency to treat simple fractures with osteosynthesis. Patients between 65 and 79 with an osteosynthesis had benefits in almost every comparison. Patients ≥ 80 with a plate fixation had advantages in the categories of postoperative complications, blood loss and transfusion of erythrocyte concentrates. Statistical significant differences were noticed in both groups regarding the operation time. Patients between 65 and 79 with osteosynthesis had significant benefits for postoperative complications, hospitalization, number of blood transfusions and postoperative mobilization. Finding the best supportive treatment option is difficult, and decision-making must respect fracture patterns and individual risk factors. This study shows that plate fixation via the Stoppa approach has some benefits.

Lung failure after polytrauma with concomitant thoracic trauma in the elderly: an analysis from the TraumaRegister DGU®.

BACKGROUND: In developed countries worldwide, the number of older patients is increasing. Pulmonary complications are common in multiple injured patients with chest injuries. We assessed whether geriatric patients develop lung failure following multiple trauma with concomitant thoracic trauma more often than younger patients. METHODS: A retrospective analysis of severely injured patients with concomitant blunt thoracic trauma registered in the TraumaRegister DGU® (TR-DGU) between 2009 and 2018 was performed. Patients were categorized into four age groups: 55-64 y, 65-74 y, 75-84 y, and ≥ 85 y. Adult patients aged 18-54 years served as a reference group. Lung failure was defined as PaO2/FIO2 ≤ 200 mm Hg, if mechanical ventilation was performed. RESULTS: A total of 43,289 patients were included, of whom 9238 (21.3%) developed lung failure during their clinical stay. The rate of posttraumatic lung failure was seen to increase with age. While lung failure markedly increased the length of hospital stay, duration of mechanical ventilation, and length of ICU stay independent of the patient's age, differences between younger and older patients with lung failure in regard to these parameters were clinically comparable. In addition, the development of respiratory failure showed a distinct increase in mortality with higher age, from 16.9% (18-54 y) to 67.2% (≥ 85 y). CONCLUSION: Development of lung failure in severely injured patients with thoracic trauma markedly increases hospital length of stay, length of ICU stay, and duration of mechanical ventilation in patients, regardless of age. The development of respiratory failure appears to be related to the severity of the chest trauma rather than to increasing patient age. However, the greatest effects of lung failure, particularly in terms of mortality, were observed in the oldest patients.

Acute alcohol consumption increases systemic endotoxin bioactivity for days in healthy volunteers-with reduced intestinal barrier loss in female.

OBJECTIVE: Trauma is the most common cause of death among young adults. Alcohol intoxication plays a significant role as a cause of accidents and as a potent immunomodulator of the post-traumatic response to tissue injury. Polytraumatized patients are frequently at risk to developing infectious complications, which may be aggravated by alcohol-induced immunosuppression. Systemic levels of integral proteins of the gastrointestinal tract such as syndecan-1 or intestinal fatty acid binding proteins (FABP-I) reflect the intestinal barrier function. The exact impact of acute alcohol intoxication on the barrier function and endotoxin bioactivity have not been clarified yet. METHODS: 22 healthy volunteers received a precisely defined amount of alcohol (whiskey-cola) every 20 min over a period of 4 h to reach the calculated blood alcohol concentration (BAC) of 1‰. Blood samples were taken before alcohol drinking as a control, and after 2, 4, 6, 24 and 48 h after beginning with alcohol consumption. In addition, urine samples were collected. Intestinal permeability was determined by serum and urine values of FABP-I, syndecan-1, and soluble (s)CD14 as a marker for the endotoxin translocation via the intestinal barrier by ELISA. BAC was determined. RESULTS: Systemic FABP-I was significantly reduced 2 h after the onset of alcohol drinking, and remained decreased after 4 h. However, at 6 h, FABP-I significantly elevated compared to previous measurements as well as to controls (p < 0.05). Systemic sCD14 was significantly elevated after 6, 24 and 48 h after the onset of alcohol consumption (p < 0.05). Systemic FABP-I at 2 h after drinking significantly correlated with the sCD14 concentration after 24 h indicating an enhanced systemic LPS bioactivity. Women showed significantly lower levels of syndecan-1 in serum and urine and urine for all time points until 6 h and lower FABP-I in the serum after 2 h. CONCLUSIONS: Even relative low amounts of alcohol affect the immune system of healthy volunteers, although these changes appear minor in women. A potential damage to the intestinal barrier and presumed enhanced systemic endotoxin bioactivity after acute alcohol consumption is proposed, which represents a continuous immunological challenge for the organism and should be considered for the following days after drinking.

Alterations of Phagocytic Activity and Capacity in Granulocytes and Monocytes Depend on the Pathogen Strain in Porcine Polytrauma.

Background: Polytraumatized patients undergo a strong immunological stress upon insult. Phagocytes (granulocytes and monocytes) play a substantial role in immunological defense against bacteria, fungi and yeast, and in the clearance of cellular debris after tissue injury. We have reported a reduced monocytes phagocytic activity early after porcine polytrauma before. However, it is unknown if both phagocyte types undergo those functional alterations, and if there is a pathogen-specific phagocytic behavior. We characterized the phagocytic activity and capacity of granulocytes and monocytes after polytrauma. Methods: Eight pigs (Sus scrofa) underwent polytrauma consisting of lung contusion, liver laceration, tibial fracture and hemorrhagic shock with fluid resuscitation and fracture fixation with external fixator. Intensive care treatment including mechanical ventilation for 72 h followed. Phagocytic activity and capacity were investigated using an in vitro ex vivo whole blood stimulation phagocytosis assays before trauma, after surgery, 24, 48, and 72 h after trauma. Blood samples were stimulated with Phorbol-12-myristate-13-acetate and incubated with FITC-labeled E. coli, S. aureus or S. cerevisiae for phagocytosis assessment by flow cytometry. Results: Early polytrauma-induced significant increase of granulocytes and monocytes declined to baseline values within 24 h. Percentage of E. coli-phagocytizing granulocytes significantly decreased after polytrauma and during further intensive care treatment, while their capacity significantly increased. Interestingly, both granulocytic phagocytic activity and capacity of S. aureus significantly decreased after trauma, although a recovery was observed after 24 h and yet was followed by another decrease. The percentage of S. cerevisiae-phagocytizing granulocytes significantly increased after 24 h, while their impaired capacity after surgery and 72 h later was detected. Monocytic E. coli-phagocytizing percentage did not change, while their capacity increased after 24-72 h. After a significant decrease in S. aureus-phagocytizing monocytes after surgery, a significant increase after 24 and 48 h was observed without capacity alterations. No significant changes in S. cerevisiae-phagocytizing monocytes occurred, but their capacity dropped 48 and 72 h. Conclusion: Phagocytic activity and capacity of granulocytes and monocytes follow a different pattern and significantly change within 72 h after polytrauma. Both phagocytic activity and capacity show significantly different alterations depending on the pathogen strain, thus potentially indicating at certain and possibly more relevant infection causes after polytrauma.

Club Cell Protein 16 Attenuates CD16brightCD62dim Immunosuppressive Neutrophils in Damaged Tissue upon Posttraumatic Sepsis-Induced Lung Injury.

BACKGROUND: Recently, identification of immunosuppressive polymorphonuclear leukocytes (PMNL) that were traditionally described as proinflammatory cells emerged in the field of posttraumatic immunity. To understand their local and remote distribution after trauma, PMNL-subsets and the impact of immunomodulatory Club Cell protein (CC)16 that correlates with pulmonary complications were assessed. METHODS: C57BL/6N mice were divided into three groups, receiving isolated blunt chest trauma (TxT), undergoing TxT followed by cecal ligation and puncture (CLP, TxT + CLP) after 24 h, or sham undergoing analgosedation (n = 18/group). Further, each group was subdivided into three groups receiving either no treatment (ctrl) or intratracheal neutralization of CC16 by application of anti-CC16-antibody or application of an unspecific IgG control antibody (n = 6/group). Treatment was set at the time point after TxT. Analyses followed 6 h post-CLP. PMNL were characterized via expression of CD11b, CD16, CD45, CD62L, and Ly6G by flow cytometry in bone marrow (BM), blood, spleen, lung, liver, and bronchoalveolar and peritoneal lavage fluid (BALF and PL). Apoptosis was assessed by activated (cleaved) caspase-3. Results from untreated ctrl and IgG-treated mice were statistically comparable between all corresponding sham, TxT, and TxT + CLP groups. RESULTS: Immature (CD16dimCD62Lbright) PMNL increased significantly in BM, circulation, and spleen after TxT vs. sham and were significantly attenuated in the lungs, BALF, PL, and liver. Classical-shaped (CD16brightCD62Lbright) PMNL increased after TxT vs. sham in peripheral tissue and were significantly attenuated in circulation, proposing a trauma-induced migration of mature or peripheral differentiation of circulating immature PMNL. Immunosuppressive (CD16brightCD62Ldim) PMNL decreased significantly in the lungs and spleen, while they systemically increased after TxT vs. sham. CLP in the TxT + CLP group reduced immunosuppressive PMNL in PL and increased their circulatory rate vs. isolated TxT, showing local reduction in affected tissue and their increase in nonaffected tissue. CC16 neutralization enhanced the fraction of immunosuppressive PMNL following TxT vs. sham and decreased caspase-3 in the lungs post-CLP in the TxT + CLP group, while apoptotic cells in the liver diminished post-TxT. Posttraumatic CC16 neutralization promotes the subset of immunosuppressive PMNL and antagonizes their posttraumatic distribution. CONCLUSION: Since CC16 affects both the distribution of PMNL subsets and apoptosis in tissues after trauma, it may constitute as a novel target to beneficially shape the posttraumatic tissue microenvironment and homeostasis to improving outcomes.

Enhanced pro-inflammatory response and higher mortality rates in geriatric trauma patients.

BACKGROUND: Age has been associated with increased morbidity and mortality after traumatic injury. Disregarding trauma-related factors, this may be caused by the diminished ability to cope with stressors due to limited reserve, the so-called frailty. Inflammation is assumed to promote frailty, and thus, pro-inflammatory markers may constitute as being predictive factors in geriatric trauma patients (TP). Here, we analyzed the influence of age on systemic inflammatory markers and outcome parameters in TP. PATIENTS AND METHODS: 204 TP with injury severity score (ISS) ≥ 16 were included and grouped to younger vs. geriatric, defining an age of 65 as cut-off. ISS, vital signs, physiological parameters, stay at the intensive-care unit (ICU) or in-hospital, and outcome parameters were analyzed. Systemic fibrinogen, interleukin (IL)-6, and IL-10 levels were determined upon admission. A p value < 0.05 was considered statistically significant. RESULTS: 43 geriatric and 161 younger TP were included. ISS (24.19 ± 9.59 vs. 26.93 ± 9.68) was comparable between both groups. Abbreviated Injury Scale (AIS) ≥ 3 of head trauma was more prevalent in geriatric TP (74.42 vs. 64.59%). In both groups, there were significantly more male than female patients; however, this disparity was significantly more distinct in younger TP. Geriatric group showed significantly lower shock indices, higher fibrinogen, and lower IL-10 levels (all p < 0.05). A significant spearman´s rank correlation with age was found for fibrinogen (positive correlation, r = 0.364, p < 0.05), and for IL-10 (negative correlation, r = - 0.168, p < 0.05). In-hospital mortality was significantly increased in geriatric TP. CONCLUSIONS: An enhanced inflammatory response is associated with higher mortality rates in geriatric trauma patients.

Early local neutralization of CC16 in sepsis­induced ALI following blunt chest trauma leads to delayed mortality without benefitting overall survival.

Blunt thoracic trauma (TxT) is a common injury pattern in polytraumatized patients. When combined with a secondary trigger, TxT often results in acute lung injury (ALI), which negatively affects outcomes. Recent findings suggest that ALI is caused by both local and systemic inflammatory reactions. Club cell protein (CC)16 is an anti­inflammatory peptide associated with lung injury following TxT. Recently, the anti­inflammatory properties of endogenous CC16 in a murine model of TxT with subsequent cecal­ligation and puncture (CLP) as the secondary hit were demonstrated by our group. The present study aimed to determine whether CC16 neutralization improves survival following 'double­hit'­induced ALI. For this purpose, a total of 120 C57BL/6N mice were subjected to TxT, followed by CLP after 24 h. Sham­operated animals underwent anesthesia without the induction of TxT + CLP. CC16 neutralization was performed by providing a CC16 antibody intratracheally following TxT (early) or following CLP (late). Survival was assessed in 48 animals for 6 days after CLP. Sacrifice was performed 6 or 24 h post­CLP to evaluate the anti­inflammatory effect of CC16. The results revealed that CC16 neutralization enhanced pro­inflammatory CXCL1 levels, thereby confirming the anti­inflammatory characteristics of CC16 in this model. Early CC16 neutralization immediately following TxT significantly prolonged survival within 60 h; however, the survival rate did not change until 6 days post­trauma. Late CC16 neutralization did not provide any survival benefits. On the whole, the present study demonstrated that neutralizing CC16 confirmed its anti­inflammatory potential in this double­hit ALI model. Early CC16 neutralization prolonged survival within 60 h; however, no survival benefits were observed after 6 days post­CLP in any group.

miR-142-3p Expression Is Predictive for Severe Traumatic Brain Injury (TBI) in Trauma Patients.

BACKGROUND: Predictive biomarkers in biofluids are the most commonly used diagnostic method, but established markers in trauma diagnostics lack accuracy. This study investigates promising microRNAs (miRNA) released from affected tissue after severe trauma that have predictive values for the effects of the injury. METHODS: A retrospective analysis of prospectively collected data and blood samples of n = 33 trauma patients (ISS ≥ 16) is provided. Levels of miR-9-5p, -124-3p, -142-3p, -219a-5p, -338-3p and -423-3p in severely injured patients (PT) without traumatic brain injury (TBI) or with severe TBI (PT + TBI) and patients with isolated TBI (isTBI) were measured within 6 h after trauma. RESULTS: The highest miR-423-3p expression was detected in patients with severe isTBI, followed by patients with PT + TBI, and lowest levels were found in PT patients without TBI (2-∆∆Ct, p = 0.009). A positive correlation between miR-423-3p level and increasing AIShead (p = 0.001) and risk of mortality (RISC II, p = 0.062) in trauma patients (n = 33) was found. ROC analysis of miR-423-3p levels revealed them as statistically significant to predict the severity of brain injury in trauma patients (p = 0.006). miR-124-3p was only found in patients with severe TBI, miR-338-3p was shown in all trauma groups. miR-9-5p, miR-142-3p and miR-219a-5p could not be detected in any of the four groups. CONCLUSION: miR-423-3p expression is significantly elevated after isolated traumatic brain injury and predictable for severe TBI in the first hours after trauma. miR-423-3p could represent a promising new biomarker to identify severe isolated TBI.

Post-Traumatic Sepsis Is Associated with Increased C5a and Decreased TAFI Levels.

BACKGROUND: Sepsis frequently occurs after major trauma and is closely associated with dysregulations in the inflammatory/complement and coagulation system. Thrombin-activatable fibrinolysis inhibitor (TAFI) plays a dual role as an anti-fibrinolytic and anti-inflammatory factor by downregulating complement anaphylatoxin C5a. The purpose of this study was to investigate the association between TAFI and C5a levels and the development of post-traumatic sepsis. Furthermore, the predictive potential of both TAFI and C5a to indicate sepsis occurrence in polytraumatized patients was assessed. METHODS: Upon admission to the emergency department (ED) and daily for the subsequent ten days, circulating levels of TAFI and C5a were determined in 48 severely injured trauma patients (injury severity score (ISS) ≥ 16). Frequency matching according to the ISS in septic vs. non-septic patients was performed. Trauma and physiologic characteristics, as well as outcomes, were assessed. Statistical correlation analyses and cut-off values for predicting sepsis were calculated. RESULTS: Fourteen patients developed sepsis, while 34 patients did not show any signs of sepsis (no sepsis). Overall injury severity, as well as demographic parameters, were comparable between both groups (ISS: 25.78 ± 2.36 no sepsis vs. 23.46 ± 2.79 sepsis). Septic patients had significantly increased C5a levels (21.62 ± 3.14 vs. 13.40 ± 1.29 ng/mL; p < 0.05) and reduced TAFI levels upon admission to the ED (40,951 ± 5637 vs. 61,865 ± 4370 ng/mL; p < 0.05) compared to the no sepsis group. Negative correlations between TAFI and C5a (p = 0.0104) and TAFI and lactate (p = 0.0423) and positive correlations between C5a and lactate (p = 0.0173), as well as C5a and the respiratory rate (p = 0.0266), were found. In addition, correlation analyses of both TAFI and C5a with the sequential (sepsis-related) organ failure assessment (SOFA) score have confirmed their potential as early sepsis biomarkers. Cut-off values for predicting sepsis were 54,857 ng/mL for TAFI with an area under the curve (AUC) of 0.7550 (p = 0.032) and 17 ng/mL for C5a with an AUC of 0.7286 (p = 0.034). CONCLUSION: The development of sepsis is associated with early decreased TAFI and increased C5a levels after major trauma. Both elevated C5a and decreased TAFI may serve as promising predictive factors for the development of sepsis after polytrauma.

Contributing factors in the development of acute lung injury in a murine double hit model.

OBJECTIVES: Blunt chest (thoracic) trauma (TxT) is known to contribute to the development of secondary pulmonary complications. Of these, acute lung injury (ALI) is common especially in multiply injured patients and might not only be due to the direct trauma itself, but seems to be caused by ongoing and multifactorial inflammatory changes. Nevertheless, the exact mechanisms and contributing factors of the development of ALI following blunt chest trauma are still elusive. METHODS: 60 CL57BL/6N mice sustained either blunt chest trauma combined with laparotomy without further interventions or a double hit (DH) including TxT and cecal ligation puncture (CLP) after 24 h to induce ALI. Animals were killed either 6 or 24 h after the second procedure. Pulmonary expression of inflammatory mediators cxcl1, cxcl5, IL-1ß and IL-6, neutrophil infiltration and lung tissue damage using the Lung Injury Score (LIS) were determined. RESULTS: Next to a moderate increase in other inflammatory mediators, a significant increase in CXCL1, neutrophil infiltration and lung injury was observed early after TxT, which returned to baseline levels after 24 h. DH induced significantly increased gene expression of cxcl1, cxcl5, IL-1ß and IL-6 after 6 h, which was followed by the postponed significant increase in the protein expression after 24 h compared to controls. Neutrophil infiltration was significantly enhanced 24 h after DH compared to all other groups, and exerted a slight decline after 24 h. LIS has shown a significant increase after both 6 and 24 h compared to both control groups as well the late TxT group. CONCLUSION: Early observed lung injury with moderate inflammatory changes after blunt chest trauma recovered quickly, and therefore, may be caused by mechanical lung injury. In contrast, lung injury in the ALI group did not undergo recovery and is closely associated with significant changes of inflammatory mediators. This model may be used for further examinations of contributing factors and therapeutic strategies to prevent ALI.

Cytokines in Inflammatory Disease.

This review aims to briefly discuss a short list of a broad variety of inflammatory cytokines. Numerous studies have implicated that inflammatory cytokines exert important effects with regard to various inflammatory diseases, yet the reports on their specific roles are not always consistent. They can be used as biomarkers to indicate or monitor disease or its progress, and also may serve as clinically applicable parameters for therapies. Yet, their precise role is not always clearly defined. Thus, in this review, we focus on the existing literature dealing with the biology of cytokines interleukin (IL)-6, IL-1, IL-33, tumor necrosis factor-alpha (TNF-α), IL-10, and IL-8. We will briefly focus on the correlations and role of these inflammatory mediators in the genesis of inflammatory impacts (e.g., shock, trauma, immune dysregulation, osteoporosis, and/or critical illness).

Club cell protein 16 in sera from trauma patients modulates neutrophil migration and functionality via CXCR1 and CXCR2.

BACKGROUND: Club Cell protein (CC)16 correlates with lung injury and respiratory complications, which are in part triggered by polymorphonuclear leukocytes (PMNL) in severely traumatized patients (TP). CC16 exerts anti-inflammatory and immunosuppressive effects, however, its influence on PMNL functions after trauma is unknown. Here, we evaluated whether CC16 present in sera from TP could modify the biological functions of PMNL. METHODS: Sera from 16 severely injured TP without pneumonia (no P, n = 8) or with pneumonia (P, n = 8) were collected at admission to emergency department (ED) and 1 day prior pneumonia and pre-incubated with or without anti-CC16 antibody for CC16 neutralization. Samples from the equal post-injury days in the corresponding no P group were used. Neutrophils were isolated from healthy volunteers (HV, n = 5) and incubated with 20% of the serum medium from TP, respectively. In PMNL, CD62L, CD11b/CD18 and CD31 expression, migratory capacity, phagocytosis rate, oxidative burst and apoptosis were investigated. In isolated PMNL, CXCR1 and CXCR2 were neutralized before stimulation with CC16, and oxidative burst, phagocytosis and apoptosis were analyzed in neutrophils and their subsets. RESULTS: Serum from the P group enhanced significantly PMNL migration compared to no P group, while CC16-neutralization further increased the migratory rate of PMNL in both groups. CC16-neutralization increased significantly the expression of CD62L in the P group at ED. Oxidative burst was significantly increased in the P group vs. no P during the study period. CC16 seemed to have no influence on oxidative burst and phagocytosis in TP. However, in a more controlled study design, CC16 induced a significant increase of oxidative burst and a decrease of apoptosis of CD16+ granulocytes. These effects were markedly observed in mature CD16brightCD62Lbright and immune suppressive CD16brightCD62Ldim neutrophils. In mature subset, CXCR1 and CXCR2 neutralization diminished CC16-induced effects. CONCLUSIONS: CC16 in sera from multiply traumatized patients, notably of those with pneumonia, has significant effects on PMNL. The results suggest an association of CC16 with CXCR1 and CXCR2. Our data suggest that CC16 reduces the migratory capacity of PMNL and thus modulates their function in patients with respiratory complications after trauma.

Endogenous Uteroglobin as Intrinsic Anti-inflammatory Signal Modulates Monocyte and Macrophage Subsets Distribution Upon Sepsis Induced Lung Injury.

Sepsis is a serious clinical condition which can cause life-threatening organ dysfunction, and has limited therapeutic options. The paradigm of limiting excessive inflammation and promoting anti-inflammatory responses is a simplified concept. Yet, the absence of intrinsic anti-inflammatory signaling at the early stage of an infection can lead to an exaggerated activation of immune cells, including monocytes and macrophages. There is emerging evidence that endogenous molecules control those mechanisms. Here we aimed to identify and describe the dynamic changes in monocyte and macrophage subsets and lung damage in CL57BL/6N mice undergoing blunt chest trauma with subsequent cecal ligation and puncture. We showed that early an increase in systemic and activated Ly6C+CD11b+CD45+Ly6G- monocytes was paralleled by their increased emigration into lungs. The ratio of pro-inflammatory Ly6ChighCD11b+CD45+Ly6G- to patrolling Ly6ClowCD11b+CD45+Ly6G- monocytes significantly increased in blood, lungs and bronchoalveolar lavage fluid (BALF) suggesting an early transition to inflammatory phenotypes during early sepsis development. Similar to monocytes, the level of pro-inflammatory Ly6ChighCD45+F4/80+ macrophages increased in lungs and BALF, while tissue repairing Ly6ClowCD45+F4/80+ macrophages declined in BALF. Levels of inflammatory mediators TNF-α and MCP-1 in blood and RAGE in lungs and BALF were elevated, and besides their boosting of inflammation via the recruitment of cells, they may promote monocyte and macrophage polarization, respectively, toward the pro-inflammatory phenotype. Neutralization of uteroglobin increased pro-inflammatory cytokine levels, activation of inflammatory phenotypes and their recruitment to lungs; concurrent with increased pulmonary damage in septic mice. In in vitro experiments, the influence of uteroglobin on monocyte functions including migratory behavior, TGF-ß1 expression, cytotoxicity and viability were proven. These results highlight an important role of endogenous uteroglobin as intrinsic anti-inflammatory signal upon sepsis-induced early lung injury, which modules the early monocyte/macrophages driven inflammation. Short Summary: Blunt chest injury is the third largest cause of death following major trauma, and ongoing excessive pro-inflammatory immune response entails high risk for the development of secondary complications, such as sepsis, with limited therapeutic options. In murine double hit trauma consisting of thoracic trauma and subsequent cecal ligation and puncture, we investigated the cytokine profile, pulmonary epithelial integrity and phenotypic shift of patrolling Ly6ClowCD11b+CD45+Ly6G- monocytes and Ly6ClowCD45+F4/80+ macrophages to pro-inflammatory Ly6ChighCD11b+CD45+Ly6G- monocytes and Ly6ChighCD45+F4/80+ cells in blood, lungs and bronchoalveolar lavage fluid (BALF). Pro-inflammatory mediators and phenotypes were elevated and uteroglobin neutralization led to further increase. Enhanced total protein levels in BALF suggests leakage of respiratory epithelium. In vitro, uteroglobin inhibited the migratory capacity of monocytes and the TGF-ß1 expression without affecting the viability. These results highlight an important role of endogenous uteroglobin as an intrinsic anti-inflammatory signal upon sepsis-induced early lung injury, which modulates the early monocyte/macrophages driven inflammation.

Early Local Inhibition of Club Cell Protein 16 Following Chest Trauma Reduces Late Sepsis-Induced Acute Lung Injury.

Blunt thoracic trauma (TxT) deteriorates clinical post-injury outcomes. Ongoing inflammatory changes promote the development of post-traumatic complications, frequently causing Acute Lung Injury (ALI). Club Cell Protein (CC)16, a pulmonary anti-inflammatory protein, correlates with lung damage following TxT. Whether CC16-neutralization influences the inflammatory course during ALI is elusive. Ninety-six male CL57BL/6N mice underwent a double hit model of TxT and cecal ligation puncture (CLP, 24 h post-TxT). Shams underwent surgical procedures. CC16 was neutralized by the intratracheal application of an anti-CC16-antibody, either after TxT (early) or following CLP (late). Euthanasia was performed at 6 or 24 h post-CLP. Systemic and pulmonary levels of IL-6, IL-1ß, and CXCL5 were determined, the neutrophils were quantified in the bronchoalveolar lavage fluid, and histomorphological lung damage was assessed. ALI induced a significant systemic IL-6 increase among all groups, while the local inflammatory response was most prominent after 24 h in the double-hit groups as compared to the shams. Significantly increased neutrophilic infiltration upon double hit was paralleled with the enhanced lung damage in all groups as compared to the sham, after 6 and 24 h. Neutralization of CC16 did not change the systemic inflammation. However, early CC16-neutralization increased the neutrophilic infiltration and lung injury at 6 h post-CLP, while 24 h later, the lung injury was reduced. Late CC16-neutralization increased neutrophilic infiltration, 24 h post-CLP, and was concurrent with an enhanced lung injury. The data confirmed the anti-inflammatory potential of endogenous CC16 in the murine double-hit model of ALI.

The ALS-linked E102Q mutation in Sigma receptor-1 leads to ER stress-mediated defects in protein homeostasis and dysregulation of RNA-binding proteins.

Amyotrophic lateral sclerosis (ALS) is characterized by the selective degeneration of motor neurons (MNs) and their target muscles. Misfolded proteins which often form intracellular aggregates are a pathological hallmark of ALS. Disruption of the functional interplay between protein degradation (ubiquitin proteasome system and autophagy) and RNA-binding protein homeostasis has recently been suggested as an integrated model that merges several ALS-associated proteins into a common pathophysiological pathway. The E102Q mutation in one such candidate gene, the endoplasmic reticulum (ER) chaperone Sigma receptor-1 (SigR1), has been reported to cause juvenile ALS. Although loss of SigR1 protein contributes to neurodegeneration in several ways, the molecular mechanisms underlying E102Q-SigR1-mediated neurodegeneration are still unclear. In the present study, we showed that the E102Q-SigR1 protein rapidly aggregates and accumulates in the ER and associated compartments in transfected cells, leading to structural alterations of the ER, nuclear envelope and mitochondria and to subsequent defects in proteasomal degradation and calcium homeostasis. ER defects and proteotoxic stress generated by E102Q-SigR1 aggregates further induce autophagy impairment, accumulation of stress granules and cytoplasmic aggregation of the ALS-linked RNA-binding proteins (RBPs) matrin-3, FUS, and TDP-43. Similar ultrastructural abnormalities as well as altered protein degradation and misregulated RBP homeostasis were observed in primary lymphoblastoid cells (PLCs) derived from E102Q-SigR1 fALS patients. Consistent with these findings, lumbar α-MNs of both sALS as well as fALS patients showed cytoplasmic matrin-3 aggregates which were not co-localized with pTDP-43 aggregates. Taken together, our results support the notion that E102Q-SigR1-mediated ALS pathogenesis comprises a synergistic mechanism of both toxic gain and loss of function involving a vicious circle of altered ER function, impaired protein homeostasis and defective RBPs.

Accumulation of STIM1 is associated with the degenerative muscle fibre phenotype in ALS and other neurogenic atrophies.

AIM: Upon denervation, skeletal muscle fibres initiate complex changes in gene expression. Many of these genes are involved in muscle fibre remodelling and atrophy. Amyotrophic lateral sclerosis (ALS) leads to progressive neurodegeneration and neurogenic muscular atrophy (NMA). Disturbed calcium homeostasis and misfolded protein aggregation both in motor neurones and muscle fibres are key elements of ALS pathogenesis that are mutually interdependent. Therefore, we hypothesized that the calcium sensor STIM1 might be abnormally modified and involved in muscle fibre degeneration in ALS and other types of NMA. METHODS: We examined ALS and NMA patient biopsy and autopsy tissue and tissue from G93A SOD1 mice by immunohistochemistry and immunoblotting. RESULTS: In normal human and mouse muscle STIM1 was found to be differentially expressed in muscle fibres of different types and to concentrate at neuromuscular junctions, compatible with its known role in calcium sensing. Denervated muscle fibres of sALS and NMA cases and SOD1 mice showed diffusely increased STIM1 immunoreactivity along with ubiquitinated material. In addition, distinct focal accumulations of STIM1 were observed in target structures within denervated fibres of sALS and other NMA as well as SOD1 mouse muscles. Large STIM1-immunoreactive structures were found in ALS-8 patient muscle harbouring the P56S mutation in the ER protein VAPB. CONCLUSION: These findings suggest that STIM1 is involved in several ways in the reaction of muscle fibres to denervation, probably reflecting alterations in calcium homeostasis in denervated muscle fibres.