Glial fibrillary acidic protein is a robust biomarker in cerebrospinal fluid and peripheral blood after traumatic spinal cord injury: a prospective pilot study.

PURPOSE: Biochemical biomarkers to determine the injury severity and the potential for functional recovery of traumatic spinal cord injury (TSCI) are highly warranted; however, it remains to be clarified whether cerebrospinal fluid (CSF) or peripheral blood (PB) is the ideal sample media. This study aims to measure and compare biomarker concentrations in CSF and PB and to explore associations between biomarker concentrations and injury severity, i.e., American Spinal Injury Association (ASIA) Impairment Scale (AIS) grade, and biomarker concentrations and clinical outcome, i.e., AIS grade improvement and Spinal Cord Independent Measure version III (SCIM-III) score. METHODS: From 2018 to 2020, we conducted a single-center prospective pilot study of TSCI patients (n=15) and healthy controls (n=15). Sample collection and clinical outcome assessment were performed at median 13 h [IQR: 19], 9 days [IQR: 2], and 148 days [IQR: 49] after TSCI. Concentrations of neuron-specific enolase (NSE); glial fibrillary acid protein (GFAP); neurofilament light chain (NfL); interferon-γ (IFN-γ); interleukin (IL)-1ß, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p70, and IL-13; and tumor necrosis factor α (TNF-α) were measured and associated to clinical outcomes. RESULTS: The biomarker concentrations were higher in CSF than PB. CSF concentrations of GFAP, NSE, IFN-y, TNF-a, IL-2, IL-12p70, IL-4, IL-10, and IL-13 and PB concentrations of GFAP and IFN-y were significantly associated with AIS grade, but not with AIS grade improvement or SCIM-III score. CONCLUSIONS: Our results support GFAP as a potential diagnostic biomarker that may be measured in CSF as well as PB.

Cerebrospinal fluid and peripheral blood proteomics in Traumatic Spinal Cord Injury: A prospective pilot study.

•Proteomics enable profiling of inflammatory responses after spinal cord injury.•Proteins are differentially expressed over time.•Proteins are differentially expressed in cerebrospinal fluid and peripheral blood.•A poor relationship exists between protein expression and neurological outcome.

The inflammatory response and blood-spinal cord barrier integrity in traumatic spinal cord injury: a prospective pilot study.

PURPOSE: Triggering of inflammatory responses and disruption of blood-spinal cord barrier (BSCB) integrity are considered pivotal events in the pathophysiology of traumatic spinal cord injury (TSCI). Yet, these events are poorly understood and described in humans. This study aims to describe inflammatory responses and BSCB integrity in human TSCI. METHODS: Fifteen TSCI patients and fifteen non-TSCI patients were prospectively recruited from Aarhus University Hospital, Denmark. Peripheral blood (PB) and cerebrospinal fluid (CSF) were collected at median day 0 [IQR: 1], median day 9 [IQR: 2], and median day 148 [IQR: 49] after injury. PB and CSF were analyzed for immune cells by flow cytometry, cytokines by multiplex immunoassay, and BSCB integrity by IgG Index. RESULTS: Eleven TSCI patients completed follow-up. Results showed alterations in innate and adaptive immune cell counts over time. TSCI patients had significantly increased cytokine concentrations in CSF at the first and second follow-up, while only concentrations of interleukin (IL)-4, IL-8, and tumor necrosis factor-α remained significantly increased at the third follow-up. In PB, TSCI patients had significantly increased IL-6, IL-8, and IL-10 concentrations and significantly decreased interferon-γ concentrations at the first follow-up. Results further showed increased IgG Index indicative of BSCB disruption in seven TSCI patients at the first follow-up, five TSCI patients at the second follow-up, and two patients at the third follow-up. CONCLUSIONS: Our results suggest that TSCI mainly triggers innate inflammatory responses that resolves over time, although with some degree of non-resolving inflammation, particularly in CSF. Our results cannot confirm BSCB disruption in all TSCI patients.

The effects of preoperative focused cardiac ultrasound in high-risk patients: A randomised controlled trial (PREOPFOCUS).

BACKGROUND: Surgery is the third most common cause of mortality worldwide. Focused cardiac ultrasound (FOCUS) yields information on cardiac status and discloses the presence of unknown pathology. Preoperative FOCUS changes patient treatment, allowing for a patient-tailored anaesthesia. We hypothesised that preoperative FOCUS would reduce the proportion of patients who were either admitted to hospital for more than 10 days or who were dead within 30 days after high-risk, non-cardiac surgery. METHODS: This was a randomised, controlled, multi-center study. Patients ≥65 years of age, admitted for urgent orthopaedic- or abdominal surgery, scheduled for general- or neuraxial anaesthesia and with ASA 3/4 were eligible for inclusion. Patients were randomised in a 1:1 ratio to preoperative FOCUS or no preoperative FOCUS performed in accordance with a predefined protocol. Primary endpoint was the proportion of patients admitted more than 10 days or who were dead within 30 days. Secondary endpoints included major complications, days of admission and changes in anaesthesia handling. RESULTS: During the second COVID-19 wave the study monitoring committee terminated the study prematurely. We included 338 patients of which 327 were included in the final analysis. In the FOCUS group, 41/163 (25%) patients met the criteria for the primary endpoint versus 35/164 (21%) for the control group, adjusted odds ratio 1.37 (95% CI 0.86-2.30), p = .36. The proportions of patients who developed major complications did not differ significantly between groups. Length of hospital stay was 4 (3-8) days in the FOCUS group and 4 (3-7) days on the control group (adjusted p = .24). CONCLUSION: The routine availability of preoperative FOCUS assessment in this cohort does not appear to reduce the risk for hospitalisation exceeding 10 days or 30-day mortality, although study enrolment was prematurely terminated.

Tranexamic Acid and Its Potential Anti-Inflammatory Effect: A Systematic Review.

Tranexamic acid (TXA) is an antifibrinolytic drug primarily used for reducing blood loss in patients with major bleedings. Animal and cell studies have shown that TXA might modulate the inflammatory response by either enhancing or inhibiting cytokine levels. Furthermore, recent human studies have found altered inflammatory biomarkers in patients receiving TXA when compared with patients who did not receive TXA. In this systematic review we investigated the effect of TXA on inflammatory biomarkers in different patient groups. A systematic literature search was conducted on the databases PubMed and Embase to identify all original articles that investigated inflammatory biomarkers in patients receiving TXA and compared them to a relevant control group. The review was performed according to the PRISMA guidelines, and the literature search was performed on November 29, 2021. Thirty-three studies were included, among which 14 studies compared patients receiving TXA with patients getting no medication, another 14 studies investigated different dosing regimens of TXA, and finally five studies examined the administration form of TXA. The present review suggests that TXA has an anti-inflammatory effect in patients undergoing orthopaedic surgery illustrated by decreased levels of C-reactive protein and interleukin-6 in patients receiving TXA compared with patients receiving no or lower doses of TXA. However, the anti-inflammatory effect was not found in patients undergoing cardiac surgery, pediatric craniosynostosis patients, or in rheumatoid arthritis patients. The inflammatory response was not affected by administration form of TXA (oral, intravenous, or topical). In conclusion, an anti-inflammatory effect of TXA was consistently found among orthopaedic patients only.

Effect of tranexamic acid on markers of inflammation in children undergoing craniofacial surgery.

BACKGROUND: Tranexamic acid (TXA) reduces blood loss and transfusion requirements during craniosynostosis surgery in small children. Possible interaction from TXA on the inflammatory system is unknown. OBJECTIVE: To evaluate the effect of TXA on a wide range of inflammatory markers in children receiving TXA in a randomized, blinded, and placebo controlled study design. METHODS: Thirty children undergoing craniosynostosis surgery with significant blood loss received TXA (bolus dose of 10 mg kg-1 followed by 8 hours continuous infusion of 3 mg kg-1  h-1 ) or placebo in a randomized, double-blinded study design. Using a new proximity extension assays employing a panel of inflammatory biomarkers samples was used for analysis of blood samples obtained pre-operatively, 4 and 24 hours after operation. RESULTS: Ninety-two inflammatory parameters were measured. TXA did not affect any of the measured parameters as compared with placebo. Among 34 of the 92 pro- and antiinflammatory parameters investigated changes were observed between pre-operative, 4 or 24 hours, respectively, reflecting immune activation during surgical stress. CONCLUSION: TXA administration in a low-dose regimen including bolus followed by 8 hours infusion during craniosynostosis surgery did not change any of 92 inflammatory markers as compared with placebo.

The effects of preoperative point-of-care focused cardiac ultrasound in high-risk patients: study protocol for a prospective randomised controlled trial.

INTRODUCTION: Perioperative mortality and morbidity remain substantial in acute surgery. Risk factors include known cardiovascular disease, but preoperative screening is insensitive to occult cardiopulmonary conditions. Focused cardiac ultrasound (FOCUS) can disclose both structural and functional cardiac disease and provides insight into the patient's haemodynamic status. This study aims to clarify whether preoperative FOCUS changes clinical outcomes in high-risk patients. METHODS: This is a multi-centre, randomised, controlled, prospective study including patients ≥ 65 years of age scheduled for acute/emergency abdominal- or orthopaedic surgery. A total of 800 patients will be randomised to ± application of preoperative FOCUS. The primary endpoint is the proportion of patients admitted to hospital > 10 days or death within 30 days of surgery. The secondary endpoints include changes in the anaesthesia approach facilitated by FOCUS, biomarkers of organ function and perioperative complications. CONCLUSIONS: The knowledge generated from this study may facilitate changes in the anaesthesia evaluation and decision process and, consequently, in the entire perioperative anaesthesia clinical practice. The study has the potential to reduce the risk of perioperative cardiopulmonary complications which directly implies improved patient outcome and reduced hospital costs. FUNDING: The Research Fund of the Department of Anaesthesiology, Randers Regional Hospital, The Central Denmark Region's Medical Research Fund and the Hospital of Southern Jutland. TRIAL REGISTRATION: NCT03501927.

The use of the soluble adhesion molecules sE-selectin, sICAM-1, sVCAM-1, sPECAM-1 and their ligands CD11a and CD49d as diagnostic and prognostic biomarkers in septic and critically ill non-septic ICU patients.

Endothelial activation is pivotal in the development and escalation of sepsis. Central to endothelial activation is the endothelial up-regulation of cellular adhesion molecules (CAMs) including E-selectin, ICAM-1, VCAM-1, and PECAM-1. Shed CAMs are also found in circulating soluble forms (sCAMs). We investigated whether sCAMs can be used as biomarkers for the differentiation between septic and non-septic patients. Furthermore, we investigated lymphocyte and monocyte expression of LFA-1 (CD11a/CD18) and VLA-4 (CD49d/CD29) ligands for ICAM-1 and VCAM-1, respectively. Twenty-one septic and 15 critically ill non-septic patients were included. All patients had an APACHE II score above 13 at ICU admission. Fifteen healthy volunteers served as controls. Flow cytometry was used to estimate levels of sE-selectin, sICAM-1, sVCAM-1, sPECAM-1, and the cellular expression of CD11a and CD49d. Levels of sE-selectin, sICAM-1 and sPECAM-1 were higher in the septic patients compared with the non-septic patients and controls at admission and during the observation period. Lymphocyte and monocyte expression of CD11a and CD49d was suppressed or unaltered in the septic patients compared with the non-septic patients and controls. Levels of sE-selectin, sICAM-1, and sPECAM-1 were able to discriminate between septic and non-septic patients, indicating that sCAMs may be potential diagnostic biomarkers of sepsis.

Life-threatening necrotizing myometritis, due to Group A streptococcus - still a life-threatening condition.

Puerperal infection with Group A streptococcus (GAS) can present with few symptoms and rapidly progress to a life-threatening condition. Often, the infection can be treated with antibiotics. Delay in diagnosis increases risk of sepsis, multiorgan failure, and death. GAS infection is a differential diagnose for all postpartum women with unexplained symptoms.

Monocyte expression and soluble levels of the haemoglobin receptor (CD163/sCD163) and the mannose receptor (MR/sMR) in septic and critically ill non-septic ICU patients.

BACKGROUND: The diagnosis of sepsis is challenging and there is an unmet need for sensitive and specific diagnostic and prognostic biomarkers. Following activation of macrophages and monocytes, the haptoglobin-haemoglobin receptor (CD163) and the mannose receptor (MR) are shed into the circulation (sCD163 and sMR). OBJECTIVE: We investigated monocyte expression of CD163 and MR, and levels of sCD163 and sMR in septic and non-septic patients, and in healthy controls. We hypothesised that these receptors are elevated during sepsis and can be used diagnostic and prognostic. METHODS: Twenty-one patients with severe sepsis or septic shock and 15 critically ill non-septic patients were included in this prospective observational study at three ICUs at Aarhus University Hospital and Randers Regional Hospital, Denmark. Fifteen age- and gender-matched healthy volunteers served as controls. Levels of sCD163 and sMR were measured using a sandwich ELISA and monocyte expression of CD163 and MR was evaluated by flow cytometry during the first four days of ICU stay. The diagnostic and prognostic values of the receptors were assessed using AUROC curves. RESULTS: At ICU admission and during the observation period, monocyte expression of CD163 and levels of sCD163 and sMR were significantly higher in septic patients compared with non-septic patients and healthy controls (p<0.01 for all comparisons). Monocytes did not express MR. The diagnostic values estimated by AUROC were 1.00 for sMR, 0.95 for sCD163, 0.87 for CRP, and 0.75 for monocyte-bound CD163. Among the septic patients, monocyte expression of CD163 was higher in non-survivors compared with survivors at ICU admission (p = 0.02) and during the observation period (p = 0.006). The prognostic value of monocyte-bound CD163 estimated by AUROC at ICU admission was 0.82. CONCLUSION: The macrophage-specific markers CD163, sCD163, and sMR are increased in septic patients. Particularly sMR is a promising new biomarker of sepsis.

Soluble adhesion molecules correlate with surface expression in an in vitro model of endothelial activation.

Endothelial activation is a pivotal event in the development and progression of inflammation. Central to endothelial activation is the up-regulation of cellular adhesion molecules (CAMs) including E-selectin (CD62E), ICAM-1 (CD54), VCAM-1 (CD106) and PECAM-1 (CD31). These CAMs are also found in soluble forms (sCAMs). In this in vitro study of endothelial activation, we examined whether the levels of sCAMs correlate with the endothelial surface expression of CAMs in a dose-dependent and time-dependent manner. Such a correlation would support the use of sCAMs as surrogate markers for endothelial activation in inflammatory conditions. Human umbilical vein endothelial cells (HUVEC) were cultured with various concentrations of TNF-α for 8 hr and at a fixed concentration of TNF-α for various durations. The levels of soluble and surface-bound E-selectin, ICAM-1, VCAM-1 and PECAM-1 were quantified by flow cytometry. TNF-α stimulation increased CAM and sCAM expression in a dose-dependent and time-dependent manner. There was a significant positive correlation between the levels of ICAM-1 and sICAM-1 and between the levels of VCAM and sVCAM-1 in both the dose-response and time-response experiments. A positive correlation between the levels of E-selectin and sE-selectin was observed in the time-response experiment. This study supports the use of sCAMs as potential biomarkers of endothelial activation. In particular, the use of sICAM-1, sVCAM-1 and sE-selectin seems promising.

Lymphocyte apoptosis is resistant to erythropoietin in porcine endotoxemia.

Sepsis-induced lymphocyte apoptosis plays an important role in the development of immune suppression in septic patients. Erythropoietin (EPO) is a multifunctional cytokine with antiapoptotic properties. We hypothesized that EPO could mitigate mononuclear cell (MNC) apoptosis and modify the dynamic changes of MNCs during endotoxemia. Twenty-six pigs were randomized into three groups: (i) lipopolysaccharides (LPS), (ii) EPO (epoetin-α, 5000 IU/kg) administered 60 min prior to LPS, and (iii) sham. At 120 min of endotoxemia, the animals were fluid resuscitated and the LPS infusion was reduced. MNCs were isolated at 0, 60, 240, and 540 min of endotoxemia, and apoptosis was assessed by flow cytometry. Apoptosis in splenic biopsies was quantified by immunohistochemistry. Endotoxemia increased the number of apoptotic MNCs in the blood (p ≤ 0.01) and the spleen (p = 0.03), and EPO did not modify this increase. The number of T-helper and cytotoxic T cells declined during endotoxemia. The dynamic changes of the MNC subsets were not modified by treatment with EPO. In conclusion, EPO did not modify the LPS-induced changes of MNC subsets or mitigate the levels of apoptosis of MNCs in the blood or in the spleen. This study does not support that EPO confers protection against lymphocyte apoptosis.

Natural killer cells as biomarkers of hyperbaric stress during a dry heliox saturation dive.

INTRODUCTION: Diving, hyperbaric oxygen, and decompression have been described as inducers of alterations in various components of the human immune system, such as the distribution of circulating lymphocytes. Hypothetically, the monitoring of specific lymphocyte subsets during hyperbaric exposure, including T- and NK-cell subsets, can serve as biomarkers of hyperbaric stress. METHODS: Eight experienced saturation divers and eight reference subjects, naive to deep saturation diving, were examined. Peripheral blood mononuclear cells were isolated before and at different points during a 19.3-d dry heliox saturation dive to 2.64 MPa (254 msw). The NK cell cytotoxicity was estimated in a 4-h 51Cr-release assay using the NK cell sensitive tumor cell-line K562 as target cells. The major lymphocyte subpopulations, with special emphasis on the NK cell subsets, were phenotypically delineated by the use of 4-color flow cytometry. RESULTS: Although NK cell cytotoxicity increased significantly in the divers during the compression phase and the reference subjects who remained in normoxic conditions outside the chamber, the NK cell cytotoxicity was significantly higher in the divers. DISCUSSION: This finding, together with augmentation in the absolute number of circulating NK cells in the divers due to a possible activation of specific parts of the innate cellular immune system during hyperbaric exposure, suggests the monitoring of specific immune functions can be useful as biomarkers of hyperbaric-induced inflammatory stress.

Leukocyte, plasma, and organ-associated cytokine profiles in an animal model of acute inflammation.

Systemic administered lipopolysaccharide (LPS) induces a cytokine response in peripheral blood without correlations with cytokine content at the organ level. We hypothesised (1) that cytokine mRNA expression in peripheral blood mononuclear cells (PBMCs) preceded the plasma cytokine increase during endotoxaemia and (2) that statins as anti-inflammatory agents modified the LPS-induced cytokine responses. 30 pigs were randomised into 3 groups: placebo (I) or atorvastatin 80 mg (II) for 21 days, followed by LPS-infusion on day 22, or controls (III). LPS was infused at increasing concentrations (2.5 to 15 microg/kg/h) for 30 min, followed by sustained infusion (2.5 microg/kg/h) for 330 min. We measured plasma IL-6, IL-10, and TNF-alpha, and their mRNA expression in PBMCs during the LPS-infusion, and the cytokine content in kidney and heart biopsies at 360 min. LPS reduced TNF-alpha mRNA in PBMCs at 60 min, whereas IL-6 mRNA increased at 240 min. There were no correlations with plasma cytokines, which peaked at 60 min (IL-10 and TNF-alpha) and 240 min (IL-6). Cytokine content did not increase in organs, and no effects of statins could be demonstrated. In conclusion, LPS-infusion reduced leukocyte TNF-alpha mRNA and increased IL-6 mRNA, whereas plasma TNF-alpha, IL-6, and IL-10 increased markedly.

The effect of activated protein C on plasma cytokine levels in a porcine model of acute endotoxemia.

OBJECTIVE: To assess the anti-inflammatory effects of recombinant human activated protein C (rhAPC) in a porcine model of acute endotoxemia. DESIGN AND SETTING: Animal randomized controlled study at the Laboratory of Clinical Institute, Aarhus University Hospital. SUBJECTS: Eighteen female landrace pigs (30 kg). INTERVENTIONS: By pairwise randomization, pigs were given either LPS or LPS and rhAPC. Both groups received a stepwise increasing LPS infusion for 30[Symbol: see text]min; whereafter the infusion continued at a lower rate (300 min LPS in both groups). The LPS+rhAPC group received rhAPC (100 microg/kg per hour) 15 min before the LPS infusion began and throughout the trial period. RESULTS: While rhAPC showed no modifying effects on peak plasma levels of pro- or anti-inflammatory cytokines (TNF-alpha, IL-6, IL-8, IL-10), TNF-alpha and IL-10 peaked significantly later in the rhAPC-treated animals. The profibrinolytic effects of rhAPC were confirmed by decreased plasminogen activator inhibitor 1 levels, while no differences were found in other coagulation markers, hemodynamic, metabolic, or leukocyte data between the two groups. CONCLUSIONS: We found no significant effect of rhAPC on plasma levels of either pro- or anti-inflammatory cytokines in this porcine model of acute endotoxemia. However, TNF-alpha and IL-10 peaked significantly later in the rhAPC-treated animals.

Infusion of hypertonic saline (7.5%) does not change neutrophil oxidative burst or expression of endothelial adhesion molecules after abdominal hysterectomy.

BACKGROUND: Previous studies found hypertonicity to affect neutrophils in intact laboratory animals and in human blood cell cultures. We investigated whether infusion of hypertonic saline in a clinical relevant dose before hysterectomy affected peripheral blood neutrophils and their response to surgery. METHODS: Fifteen women scheduled for open abdominal hysterectomy were randomized double-blindly to infusion of 4 mL/kg 7.5% NaCl, 4 mL/kg 0.9% NaCl, or 32 mL/kg 0.9% NaCl over 20 minutes. Blood was collected at baseline, after infusion, 1, 4, and 24 hours postoperatively for the determination of leukocyte and differential count, neutrophil membrane expression of endothelial adhesion molecules by flow cytometry, and O2- -generation by superoxide dismutase-inhibitable reduction of cytochrome C. RESULTS: Surgery induced well-known changes in the number and distribution of white blood cells, reduced the expression of adhesion molecules, and halved the superoxide production unrelated to the tonicity or volume of the infused fluids. CONCLUSION: Infusion of a clinically relevant dose of hypertonic saline has no detectable effect on the membrane expression of endothelial adhesion molecules or O2- -generation in circulating neutrophils after elective abdominal hysterectomy.

Phenotypic characterisation of porcine counterparts of human NK cell populations--implications for pre-clinical studies.

The phenotype of cryopreserved crossbred porcine PBMC, with special emphasis on NK cell related surface markers, was characterised. The phenotype expressed prior to stimulation with rHu IL2 and rHu IL12 was related to the in vitro cytotoxic capacity estimated in a 4-h or 21-h 51Cr-release assay. PBMC incubated in growth medium without addition of cytokines were used to investigate the spontaneous cytotoxic capacity. The results of this study suggest that crossbred porcine PBMC comprise a specific subset expressing the phenotype CD2+CD3-CD4-CD8+SWC3-CD16+CD21-. No spontaneous cytotoxicity of the PBMC could be estimated, but the expression of CD16 seems to be a basic marker of the cytokine induced cytotoxic activity. This study suggests that cryopreserved porcine PBMC can be used when possible influences on the porcine NK cell system are investigated in relation to disease models conducted experimentally in crossbred pigs.