S100 calcium-binding protein B (S100B) has been proposed as a biomarker of brain injury after aneurysmal subarachnoid hemorrhage (aSAH), although the clinical utility of serial measurements remains uncertain. This prospective observational study investigated whether longitudinal serum and cerebrospinal fluid (CSF) S100B concentrations are associated with delayed cerebral ischemia (DCI), inflammatory activation, and neurological outcome. Twenty-six consecutive patients with aSAH underwent serial serum and CSF S100B measurements throughout hospitalization. Associations between S100B concentrations, DCI, disease severity, inflammatory biomarkers, and 3-month neurological outcome were analyzed. Admission serum S100B concentrations were significantly higher in patients who subsequently developed DCI (152.6 vs. 21.0 ng/L, p = 0.012) and correlated with disease severity and inflammatory biomarkers. Admission serum S100B was associated with DCI and showed good discriminative ability for DCI (AUC 0.79) and unfavorable 3-month outcome (AUC 0.86). Longitudinal analyses showed persistently elevated serum S100B concentrations in patients who developed DCI, while serum and CSF S100B exhibited similar temporal profiles throughout the observation period Serial serum S100B measurements appear to reflect the temporal evolution of secondary brain injury after aSAH and may provide complementary biological information alongside established clinical assessment.

Background: Hemolysis during sepsis may be driven by patient-specific factors, including the intensity of the inflammatory response and the etiology of infection, as well as treatment-related factors, such as the use of extracorporeal life-support devices. Methods: We evaluated the incidence of hemolysis—reflected by decreased plasma levels of haptoglobin and hemopexin—in a cohort of septic patients with acute respiratory failure (n = 50) admitted to the intensive care unit (ICU). Results: Hemolysis was observed in 60% of patients. Its incidence was significantly higher among those with septic shock (86%) and those receiving extracorporeal membrane oxygenation (ECMO) therapy (81%). While continuous renal replacement therapy (CRRT) alone did not increase the incidence of hemolysis, its combination with ECMO was associated with hemolysis in 100% of those treated. Logistic regression analysis identified low haptoglobin levels (odds ratio [OR] 27.1), advanced age (OR 1.2), and stage 3 acute kidney injury (OR 22.2) as significant predictors of mortality. Conclusions: These findings highlight the clinical relevance of monitoring hemolysis in septic patients. Given the routine availability of haptoglobin and hemopexin assays in most hospital laboratories, these biomarkers offer practical and accessible tools for the detection and monitoring of hemolysis in critically ill patients.

Coronary artery bypass grafting (CABG) with cardiopulmonary bypass (CPB) is associated with the transient activation of a systemic inflammatory response. Fibronectin (FN), an endogenous inflammatory mediator, is a key component of the extracellular matrix. This study aimed to detect changes in cellular and plasma FN levels, as well as its potential fragmentation or FN-fibrin complex formation, in 40 patients undergoing CABG with CPB. Our results indicate that CPB was associated with changes in the levels of cellular and plasma FN and with intensified FN fragmentation. Moreover, FN-fibrin complexes were detected in all patients, indicating activation of the coagulation process during CPB. In a multivariate regression analysis, a history of arterial hypertension and CPB duration influenced plasma FN levels at 6 h (beta = -0.458, p = 0.001; -0.375, p = 0.008, respectively) and 12 h (beta = -0.293, p = 0.026; -0.554, p = 0.000) after surgery. Alterations in FN concentration, intensified FN degradation, and the presence of FN-fibrin complexes after surgery may suggest that these changes are related to the remodelling of the extracellular matrix resulting from cardiac surgery and the associated repair processes. The results indicate that FN has clinical potential as a marker of repair processes.

Coronary heart disease is one of the most common lifestyle diseases and one of the treatment methods is coronary artery bypass grafting. The use of cardiopulmonary bypass (CPB) during this procedure is associated with the transient activation of a systemic inflammatory response and may lead to several intra-and postoperative complications. Fibronectin (FN), an adhesive glycoprotein that is a key component of the extracellular matrix, is widely distributed in human body fluids. It is one of the endogenous mediators involved in both the inflammatory response and coagulation. We aimed to detect changes in the level of fibronectin and its possible fragmentation or forming of complexes with fibrine during coronary artery bypass grafting with cardiopulmonary bypass. Our results indicate that the CPB procedure is associated with significant changes in levels of fibronectin. Elevated levels after surgery, as well as slight increases in the amount of FN degradation products in relation to the duration of CPB may suggest that these increases are related to extracellular matrix remodeling resulting from cardiac surgery and the initiation of repair processes. The results indicate that fibronectin has clinical potential as a marker of repair processes.

The aim of this prospective, observational study was to assess whether changes in the level of endocan, a marker of endothelial damage, may be an indicator of clinical deterioration and mortality in critically ill COVID-19 patients. Endocan and clinical parameters were evaluated in 40 patients with acute respiratory failure on days 1–5 after admission to the intensive care unit. Endocan levels were not related to the degree of respiratory failure, but to the presence of cardiovascular failure. In patients with cardiovascular failure, the level of endocan increased over the first 5 days (1.63, 2.50, 2.68, 2.77, 3.31 ng/mL, p = 0.016), while in patients without failure it decreased (1.51, 1.50, 1.56, 1.42, 1.13 ng/mL, p = 0.046). In addition, mortality was more than twice as high in patients with acute cardiovascular failure compared to those without failure (68% vs. 32%, p = 0.035). Baseline endocan levels were lower in viral than in bacterial infections (1.57 ng/mL vs. 5.25 ng/mL, p < 0.001), with a good discrimination between infections of different etiologies (AUC of 0.914, p < 0.001). In conclusion, endocan levels are associated with the occurrence of cardiovascular failure in COVID-19 and depend on the etiology of the infection, with higher values for bacterial than for viral sepsis.

Gastrointestinal (GI) failure can be both a cause of sepsis and a consequence of the systemic pro-inflammatory response in sepsis. Changes in biomarkers of enterocyte damage, citrulline and I-FABP (intestinal fatty acid binding protein), may indicate altered intestinal permeability and damage. The study group consisted of patients with sepsis (N = 28) and septic shock (N = 30); the control group included patients without infection (N = 10). Blood samples were collected for citrulline and I-FABP and a 4-point AGI score (acute GI injury score) was calculated to monitor GI function on days 1, 3, 5, 7, and 10. Citrulline concentrations in the study group were lower than in the control. Lower values were also noted in septic patients with shock when compared to the non-shock group throughout the study period. I-FABP was higher in the septic shock group than in the sepsis group only on days 1 and 3. Citrulline was lower in patients with GI failure (AGI III) when compared to AGI I/II, reaching significance on days 7 (p = 0.034) and 10 (p = 0.015); moreover, a higher AGI score was associated with an increased 28 day mortality (p = 0.038). The results indicate that citrulline measurements, along with the AGI assessment, have clinical potential in monitoring GI function and integrity in sepsis.

The SARS-CoV-2 virus alters the expression of genes for extracellular matrix proteins, including fibronectin. The aim of the study was to establish the relationship between different forms of fibronectin, such as plasma (pFN), cellular (EDA-FN), and proteolytic FN-fragments, and disease severity and mortality of critically ill patients treated in the intensive care unit. The levels of pFN, EDA-FN, and FN-fragments were measured in patients with a viral (N = 43, COVID-19) or bacterial (N = 41, sepsis) infection, using immunoblotting and ELISA. The level of EDA-FN, but not pFN, was related to the treatment outcome and was significantly higher in COVID-19 Non-survivors than in Survivors. Furthermore, EDA-FN levels correlated with APACHE II and SOFA scores. FN-fragments were detected in 95% of COVID-19 samples and the amount was significantly higher in Non-survivors than in Survivors. Interestingly, FN-fragments were present in only 56% of samples from patients with bacterial sepsis, with no significant differences between Non-survivors and Survivors. The new knowledge gained from our research will help to understand the differences in immune response depending on the etiology of the infection. Fibronectin is a potential biomarker that can be used in clinical settings to monitor the condition of COVID-19 patients and predict treatment outcomes.

Fibronectin (FN) plays an essential role in the host's response to infection. In previous studies, a significant decrease in the FN level was observed in sepsis; however, it has not been clearly elucidated how this parameter affects the patient's survival. To better understand the relationship between FN and survival, we utilized innovative approaches from the field of explainable machine learning, including local explanations (Break Down, Shapley Additive Values, Ceteris Paribus), to understand the contribution of FN to predicting individual patient survival. The methodology provides new opportunities to personalize informative predictions for patients. The results showed that the most important indicators for predicting survival in sepsis were INR, FN, age, and the APACHE II score. ROC curve analysis showed that the model's successful classification rate was 0.92, its sensitivity was 0.92, its positive predictive value was 0.76, and its accuracy was 0.79. To illustrate these possibilities, we have developed and shared a web-based risk calculator for exploring individual patient risk. The web application can be continuously updated with new data in order to further improve the model.

Gastrointestinal symptoms are common in critically ill COVID-19 patients. There is currently no generally recognized method of assessing gastrointestinal injury in unconscious or sedated intensive care unit (ICU) patients. I-FABP (intestinal fatty acid binding protein) and citrulline have previously been studied as potential biomarkers of enterocyte damage in various gastrointestinal tract diseases, and changes in the levels of these markers may reflect intestinal wall damage in COVID-19. Patients with critical COVID-19, with diagnosed sepsis, or septic shock requiring ICU treatment were included in the study. Blood samples for citrulline and I-FABP were taken daily from day 1 to 5. I-FABP levels were significantly higher in patients who eventually died from COVID-19 than in survivors, and the optimal I-FABP cut-off point for predicting 28-day mortality was 668.57 pg/mL (sensitivity 0.739, specificity 0.765). Plasma levels of I-FABP, but not citrulline, were associated with significantly higher mortality and appeared to be a predictor of poor outcome in multivariate logistic regression analysis. In conclusion, I-FABP seems to be an effective prognostic marker in critically ill COVID-19 patients. Assessing mortality risk based on intestinal markers may be helpful in making clinical decisions regarding the management of intestinal injury, imaging diagnostics, and potential surgical interventions.

Background . There is a pressing need for specific prognostic markers that could be used to monitor the severity of sepsis. The aims of our study were to investigate changes in the expression of different molecular forms of fibronectin in sepsis and to assess their relationship to the clinical severity and mortality of patients. Material and Methods . Forms of fibronectin: plasma (pFN), cellular (EDA-FN), FN-fibrin complexes, and fibronectin fragments were analyzed in 71 sepsis patients (survivors and nonsurvivors) and in the control by ELISA and immunoblotting. Results . The baseline pFN concentration of patients with sepsis was significantly lower than in the control (133.0 mg/L vs. 231.2 mg/L) (P<0.001), and in nonsurvivors, it was lower than in survivors (106.0 mg/L vs. 152.8 mg/L) (P=0.004). The baseline EDA-FN was significantly elevated in both sepsis groups (survivors: 6.7 mg/L; nonsurvivors: 9.4 mg/L) compared to the control (1.4 mg/L) (P<0.001). It should be noted that among patients with more severe sepsis, the EDA-FN level was higher in nonsurvivors than in survivors. Furthermore, molecular FN-fibrin complexes as well as FN fragments occurred much more frequently in nonsurvivors than in survivors. Conclusion . The study showed that in sepsis, changes in plasmatic and cellular form of fibronectin were associated with the severity of sepsis and may be useful predictors of outcome.

Fibronectin (FN) is a widely distributed glycoprotein which is present in different bodily fluids, on the surface of cells and in the extracellular matrix (ECM). It plays roles in various processes, including cell adhesion, migration, growth, proliferation, and tissue repair. Fibronectin exists in 2 forms: a soluble, inactive molecule, called plasma FN (pFN), which is synthesized by hepatocytes in the liver, and an insoluble cellular form (cFN), which is produced locally by different types of cells and is a key component of the ECM. Fibrinogen fibrils ensure structural support for cell adhesion and promote cell migration, proliferation and apoptosis. Additionally, FN controls the availability of growth factors. The plasma form of FN is a crucial component of the fibrin clot in the early wound-healing response, while the cellular form of FN supports efficient platelet adhesion, activation, aggregation, and procoagulant activity. Alternative splicing of the FN gene results in the generation of protein variants which contain the additional isoforms - extra domain A of FN (EDA) and extra domain A of FN (EDB); these are associated with, e.g., tissue remodeling, fibroblast differentiation, inflammation, and tumor progression. Fibronectin also serves as a target for a large number of bacterial proteins, and as part of a 3-component bridge (EN, integrin and FN-binding proteins - FnBPs) it contributes to bacterial colonization of endothelial and epithelial cells. Fibronectin has been identified in sepsis in humans as a negative acute-phase protein, and a low level of FN seems to be a marker of a poor prognosis fora patient. Here, the role of FN in inflammatory processes and sepsis is presented.

BACKGROUND:Bladder cancer diagnosis and surveillance includes cystoscopy and cytology. New methods for the detection of bladder cancer are needed, because cystoscopy is invasive and expensive, and because urine cytology is not sensitive enough.OBJECTIVES:The aim of the study was to select potential plasma protein markers for bladder cancer which could be useful in developing a specific laboratory test to improve diagnosis and to establish treatment strategies in order to prevent the recurrence of the disease.MATERIAL AND METHODS:Plasma proteome maps were prepared based on 2-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), combined with image gel analysis and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry of plasma samples from patients with urothelial bladder cancer, and they were compared to normal samples.RESULTS:The analyses of bladder cancer plasma samples allowed us to distinguish 3 groups of proteins whose relative abundance differed from that in normal samples. The 1st one comprised modified forms of plasma transferrin, fibrinogen gamma and complement C3b, which were absent in normal plasma. The 2nd group comprised haptoglobin, alpha-2-macroglobulin, vitamin D-binding protein, and pigment epithelium-derived factor, which occurred in the cancerous samples in large quantities. The 3rd group consisted of 3 molecular forms of immunoglobulin M (IgM), the relative abundance of which was significantly lower in the cancerous plasma samples.CONCLUSIONS:The data indicated potential plasma biomarkers associated with inflammation, immunity and coagulation processes accompanying bladder cancer. They could be used for the development of a laboratory test(s) useful in clinical practice.

Background: Multimorbidity is the co-occurrence of chronic diseases associated with low-grade chronic inflammation of connective tissue.Aim of study: Frequency of occurrence and relative amounts of fibronectin (FN) complexes with fibrin (FN-fibrin) and FN monomer were analyzed in 130 plasma samples of 18 to 94-year-old multimorbid patients in relation to concentrations of FN and extra domain A (EDA)-FN, and C-reactive protein (CRP) as well as to age, number of coexisting chronic diseases and presence of specified diseases.Results: Immunoblotting revealed, besides FN dimer, the presence of FN monomer, and 750-, 1000-, and 1300-kDa FN-fibrin complexes in the multimorbid plasmas. The FN-fibrin complexes appeared more frequently and in higher relative amounts, but FN monomer less frequently and in a lower relative amount in the groups of elderly multimorbid patients, with a higher number of coexisting diseases and with dominance of cardiovascular diseases and osteoarthrosis, and with CRP concentration of 3-5 mg/l. In contrast, the normal plasma contained only the FN-fibrin complex of 750 kDa in a lower relative amount, but with an increasing amount with normal aging. Moreover, FN concentration increased and EDA-FN decreased with the number of co-existing diseases and aging of patients, although both concentration values were lower than in the age-matched normal groups. FN concentration was the lowest in the exacerbation of a chronic disease and EDA-FN in the stable chronic disease groups.Conclusion: The alterations in plasma FN molecular status were associated with micro-inflammation and micro-coagulation, as well as multimorbidity of subjects and their physiological aging. (C) 2016 Elsevier Inc. All rights reserved.

Atherosclerosis, a chronic vascular disease, leads to molecular events bound with interplaying processes of inflammation and coagulation. In the present study, fibronectin (FN), FN containing extra domain A (EDA-FN), frequency of occurrence, and relative amounts of soluble plasma FN-fibrin complexes were analyzed in 80 plasma samples of patients suspected of coronary artery disease based on clinical evaluation and changes in arteries found by computed tomographic coronary angiography. The study showed that in the plasma of the patients’ group with high risk of coronary artery disease EDA-FN concentration was significantly higher (3.5 ± 2.5 mg/L; P < 0.025) and the molecular FN-fibrin complexes of 1000 kDa and higher occurred more often than in the groups of patients with mild risk of coronary artery disease and the normal age-matched. The increased level of EDA-FN and occurrence of FN-fibrin complexes could have a potential diagnostic value in the diagnosis and management of patients with coronary artery disease.

Objectives Fibronectin (FN) is able to bind fibrin and FN-fibrin complexes and is found in the plasma of some patients suffering from inflammatory disease. The present study was undertaken to determine whether soluble supra-molecular FN-fibrin complexes were present in the plasma of children with recurrent respiratory infections (RRI).Design and methods The frequency of occurrence and relative amounts of the supra-molecular FN-fibrin forms, concentrations of immunoglobulins and numbers of natural killer cells (NK) were determined in the plasma of children with recurrent respiratory infections. The frequencies of these parameters were compared with their frequencies in the plasma of children with acute respiratory infections and plasma from healthy children.Results SDS-agarose immunoblotting of patients' plasma revealed the presence of several additional FN-fibrin bands, with decreasing electrophoretic mobilities and increasing molecular masses of 750kDa, 1000kDa, 1300kDa, 1600kDa and 1900kDa. Such FN-fibrin complexes occurred with higher frequency and in larger amounts in the plasma of children with RRI and acute infection than they did in plasma from normal children. Moreover, bands above 1000kDa were absent in most young healthy individuals. The occurrence of FN-fibrin complexes did not correlate with either immunoglobulin concentrations, or with the number of NK cells.Conclusions The occurrence of plasma supra-molecular FN-fibrin complexes is associated with acute and recurrent respiratory infections of children.

SDS-agarose FN immunoblotting of 257 normal and pathological human plasma samples revealed the ladder pattern of multiple plasma FN bands which corresponded to FN monomer and dimer, and 5 FN-fibrin bands with increasing molecular masses. The FN-fibrin bands of about 750 kDa, 1000 kDa, 1300 kDa, 1600 kDa, and 1900 kDa appeared more frequently and in significantly higher relative amounts in the pathological samples (P < 0.000) than in relatively healthy individuals. The revealing of high-molecular FN-fibrin complexes by SDS-agarose FN immunobloting might have the potential to become a laboratory biomarker of some diseases in which the coagulation system is triggered.

OBJECTIVES:Senescence, progressive deterioration of many bodily functions might be associated with age-dependent alterations of plasma fibronectin (FN) molecular status (i.e., domain, glycotope, and molecular form expressions). DESIGN AND METHODS:FN molecular status was analyzed in 127 plasma samples of healthy individuals in groups of newborns, and subjects aged 3-14, 15-39, 41-59, and 60-82 years by FN-ELISA, lectin-FN-ELISA, and immunoblotting using a set of domain-specific monoclonal antibodies, specific lectins, and monoclonal antibody to FN, respectively. RESULTS:During the first four decades of human life the levels of cell-binding-, carboxyl-terminal-, collagen-, heparin-, and fibrin-domains of plasma FN gradually increased. In subjects aged up to 82 years the cell-binding and carboxyl-terminal FN domain concentrations did not change, while the heparin, fibrin, and collagen domains significantly increased. The relative reactivity of plasma FN with Maackia amurensis lectin, specific to α2,3-linked sialic acid, significantly decreased after birth, reaching a stable level in the subsequent life period, whereas with Sambucus nigra lectin, specific to α2,6-linked sialic acid, it significantly decreased in the 60-82 year old group. Moreover, the appearance of 280-kDa and 320-kDa FN bands, absent in young and mature healthy individuals, was found in the groups of 41-59 and 60-82 year olds. CONCLUSIONS:The alterations of FN molecular status throughout growth, maturation and senescence might be associated not only with disturbances in the balance of FN production rate and degradation, but concomitantly with conformational rearrangements of FN and its engagement in age-related vascular remodeling processes.

Three monoclonal antibodies specific to the central cell-binding and the C- and N-terminal domains of fibronectin (FN) were used to test antigenic epitope accessibility on human plasma and cerebrospinal fibronectins. In the plasma group, the mean N-terminal FN domain immunoreactivity was about one fourth that of the cell-binding and C-terminal domains, whereas in cerebrospinal fluid they were nearly equal. In the presence of 0.5-6 M urea N-terminal domain immunoreactivity in the plasma increased 3-6-fold, but it decreased 0.7-3-fold in the cerebrospinal fluid. Analysis of fibronectin domain immunoreactivities of the cell-binding and N-terminal domains by a panel of specific monoclonal antibodies may reveal N-terminal fibronectin domain accessibility for reaction with biological partner ligand(s) and/or processes in which FN could be implicated. Such determinations may have important clinical implications.

Background:Aberrant angiogenesis and senescence of the cerebrovascular system could initiate neurovascular events leading to neurovascular disorders. Fibronectin (FN) exerts a strong angiogenic influence on endothelial cells in the central nervous system. Methods: In the present study the expression of the plasma fibronectin molecular forms in an Alzheimer patient group, compared with vascular dementia and age-matched control groups was analyzed by immunoblotting. Results: FN in the plasma of the elderly individuals with and without dementia exists as a mixture of heterogeneous molecules with increasing molecular masses. Apart from the wide ∼240-kDa and ∼220-kDa FN bands, normally present in plasma, the high molecular FN forms having ∼280 kDa and ∼320 kDa appeared in the plasma of the Alzheimer dementia group more frequently and at the higher amounts than in the vascular dementia and age-matched nondemented groups. Conclusions: The plasma FN molecular status seems to be a molecular additional biomarker for assessment of dementia risk.

Objectives: Appearance of fibronectin (FN) molecular forms and alterations of domain expositions can be associated with lung cancer.Design and methods: The presence of the FN molecular forms and epitopes in its cell-binding, carboxyl-, and amino-terminal domains was determined in the plasma and pleural effusion of patients suffering from small- and non-small-cell lung cancer, and lung inflammation by immunoblotting and FN-ELISA.Results: The 320-kDa and 280-kDa FN forms as well as FN fragments appeared in the pleural effusion and plasma of patients suffering from lung inflammation or cancer in significantly higher relative amounts in both lung cancer groups than in the inflammation. The domain concentrations were higher in the cancer and inflammatory plasma groups than those in the control group. The higher N-terminal epitope expression in pleural effusion than in plasma indicates different epitope accessibility for the monoclonal antibody.Conclusions: The molecular status of FN probably reflects the dynamic changes which occur in cancer and inflammatory tissue. (C) 2009 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.