Heparin-binding protein, lysozyme, and inflammatory cytokines in bronchoalveolar lavage fluid as diagnostic tools for pulmonary infection in lung transplanted patients

Diagnostic value of plasma heparin-binding protein and the heparin-binding protein-to-albumin ratio in patients with community-acquired Pneumonia: a retrospective study

BACKGROUND

Patients presenting to the emergency department with community-acquired pneumonia (CAP) are characterized by advanced age, comorbidities, critical illness and less-than-typical symptoms, posing a diagnostic challenge. Plasma heparin-binding protein (HBP) and the heparin-binding protein-to-albumin ratio (HBP/Alb) have not been adequately studied in the early diagnosis of CAP. This study assessed the diagnostic value of plasma HBP, HBP/Alb, and conventional inflammatory markers in emergency department patients with CAP.

METHODS

We enrolled 103 patients with CAP, retrospectively analyzed the patients' clinical data, and divided the CAP patients into antibiotic (n = 79) and non-antibiotic (n = 24) groups based on whether antibiotics were administered prior to blood sampling and laboratory tests. The control group was comprised of 52 non-infected patients admitted during the same period. Within 24 h of admission, plasma HBP, serum procalcitonin (PCT), white blood cell count (WBC), neutrophil-to-lymphocyte ratio (NLR) and HBP/Alb levels were collected separately and compared. The receiver operating characteristic (ROC) curve was plotted to assess the diagnostic value of each indicator for CAP patients. Utilizing the Kappa test, the consistency of each indicator used to evaluate CAP and clinical diagnosis was analyzed. Spearman correlation was used to analyze the correlation between plasma HBP and clinical indicators of CAP patients.

RESULTS

Plasma HBP, serum PCT, WBC, NLR and HBP/Alb were all elevated in the CAP group in comparison to the control group (P < 0.001). Plasma HBP, serum PCT, WBC, NLR and HBP/Alb levels did not differ statistically between antibiotic and non-antibiotic groups (P > 0.05). Plasma HBP and HBP/Alb had the highest diagnostic accuracy for CAP, the area under the ROC curve (AUC) were 0.931 and 0.938 (P < 0.0001), and the best cut-off values were 35.40 ng/mL and 0.87, respectively. In evaluating the consistency between CAP and clinical diagnosis, the Kappa values for HBP, PCT, WBC, NLR and HBP/Alb were 0.749, 0.465, 0.439, 0.566 and 0.773, respectively. Spearman correlation analysis showed that plasma HBP was positively correlated with serum PCT, WBC, NLR and HBP/Alb in CAP patients (P < 0.001).

CONCLUSIONS

Plasma HBP and HBP/Alb have a high clinical diagnostic value for CAP and can be used as good and reliable novel inflammatory markers in the emergency department for the early diagnosis of CAP patients.

Differentiation between lung allograft rejection and infection using donor-derived cell-free DNA and pathogen detection by metagenomic next-generation sequencing

Background

In lung transplant recipients (LTRs), the primary causes of mortality are rejection and infection, which often present similar symptoms, making differentiation challenging. This study aimed to explore the diagnostic efficacy of plasma donor-derived cell-free DNA (dd-cfDNA) in conjunction with metagenomic next-generation sequencing (mNGS) for pathogen detection in differentiation between lung allograft rejection and infection in LTRs experiencing new-onset pulmonary complications.

Methods

We conducted a retrospective study on 188 LTRs who underwent lung or heart-lung transplantation at our institution from 2015 to 2021. The LTRs were categorized into three groups: stable, rejection, and infection. We measured plasma dd-cfDNA levels and utilized both mNGS and culture methods to identify pathogens in the bronchoalveolar lavage fluid (BALF).

Results

The rejection group exhibited the highest levels of plasma dd-cfDNA (median 1.34 %, interquartile range [IQR] 1.06-2.19 %) compared to the infection group (median 0.72 %, IQR 0.62-1.07 %) and the stable group (median 0.69 %, IQR 0.58-0.78 %) (both p < 0.001). Within the infection group, a significantly higher level of dd-cfDNA was observed in the cytomegalovirus infection subgroup (p < 0.001), but not in the fungal (p > 0.05) or bacterial infection subgroups (p > 0.05), when compared to the stable group. Elevated dd-cfDNA levels, in combination with negative mNGS results, strongly indicated lung allograft rejection, with a positive predictive value and negative predictive value of 88.7 % and 99.2 %, respectively.

Conclusions

Plasma dd-cfDNA in combination with BALF pathogen detection by mNGS shows satisfactory accuracy in differentiating lung allograft rejection from infectious complications.

Thymosin α1 modulated the immune landscape of COVID-19 patients revealed by single-cell RNA and TCR sequencing

BACKGROUND

The Coronavirus disease-19 (COVID-19) pandemic has posed a serious threat to global health. Thymosin α1 (Tα1) was considered to be applied in COVID-19 therapy. However, the data remains limited.

METHODS

Participants with or without Tα1 treatment were recruited. Single cell RNA-sequencing (scRNA-seq) and T cell receptor-sequencing (TCR-seq) of the peripheral blood mononuclear cell (PBMC) samples were done to analyze immune features. The differential expression analysis and functional enrichment analysis were performed to explore the mechanism of Tα1 therapy.

RESULTS

33 symptomatic SARS-CoV-2-infected individuals (COV) and 11 healthy controls (HC) were enrolled in this study. The proportion of CD3+ KLRD1+ NKT, TBX21+ CD8+ NKT was observed to increase in COVID-19 patients with Tα1 treatment (COVT) than those without Tα1 (COV) (p = 0.024; p = 0.010). These two clusters were also significantly higher in Health controls with Tα1 treatment (HCT) than those without Tα1 (HC) (p = 0.016; p = 0.031). Besides, a series of genes and pathways related to immune responses were significantly higher enriched in Tα1 groups TBX21+ CD8+ NKT, such as KLRB1, PRF1, natural killer cell-mediated cytotoxicity pathway, chemokine signaling pathway, JAK-STAT signaling pathway. The increased TRBV9-TRBJ1-1 pair existed in both HCs and COVID-19 patients after Tα1 treatment. 1389 common complementarity determining region 3 nucleotides (CDR 3 nt) were found in COV and HC, while 0 CDR 3 nt was common in COVT and HCT.

CONCLUSIONS

Tα1 increased CD3+ KLRD1+ NKT, TBX21+ CD8+ NKT cell proportion and stimulated the diversity of TCR clones in COVT and HCT. And Tα1 could regulate the expression of genes associated with NKT activation or cytotoxicity to promote NKT cells. These data support the use of Tα1 in COVID-19 patients.

Etiologic characteristics revealed by mNGS-mediated ultra-early and early microbiological identification in airway secretions from lung transplant recipients

Background

Post-operative etiological studies are critical for infection prevention in lung transplant recipients within the first year. In this study, mNGS combined with microbial culture was applied to reveal the etiological characteristics within one week (ultra-early) and one month (early) in lung transplant recipients, and the epidemiology of infection occurred within one month.

Methods

In 38 lung transplant recipients, deep airway secretions were collected through bronchofiberscope within two hours after the operation and were subjected to microbial identification by mNGS and microbial culture. The etiologic characteristics of lung transplant recipients were explored. Within one month, the infection status of recipients was monitored. The microbial species detected by mNGS were compared with the etiological agents causing infection within one month.

Results

The detection rate of mNGS in the 38 airway secretions specimens was significantly higher than that of the microbial culture (P<0.0001). MNGS identified 143 kinds of pathogenic microorganisms; bacterial pathogens account for more than half (72.73%), with gram-positive and -negative bacteria occupying large proportions. Fungi such as Candida are also frequently detected. 5 (50%) microbial species identified by microbial culture had multiple drug resistance (MDR). Within one month, 26 (68.42%) recipients got infected (with a median time of 9 days), among which 10 (38.46%) cases were infected within one week. In the infected recipients, causative agents were detected in advance by mNGS in 9 (34.62%) cases, and most of them (6, 66.67%) were infected within one week (ultra-early). In the infection that occurred after one week, the consistency between mNGS results and the etiological agents was decreased.

Conclusion

Based on the mNGS-reported pathogens in airway secretions samples collected within two hours, the initial empirical anti-infection regimes covering the bacteria and fungi are reasonable. The existence of bacteria with MDR forecasts the high risk of infection within 48 hours after transplant, reminding us of the necessity to adjust the antimicrobial strategy. The predictive role of mNGS performed within two hours in etiological agents is time-limited, suggesting continuous pathogenic identification is needed after lung transplant.

TLR4-mediated release of heparin-binding protein in human airways: a co-stimulatory role for IL-26

Background

Bacterial infection causes accumulation of neutrophils that release antimicrobial proteins including heparin-binding protein (HBP). In human airways, this neutrophil accumulation can be re-capitulated via intrabronchial exposure to lipopolysaccharide (LPS), a Toll-like receptor 4 (TLR4) agonist, that also causes a local increase in the neutrophil-mobilizing cytokine IL-26. Although LPS is considered a weak stimulus for HBP release ex vivo, its effect on HBP release in human airways in vivo has not been characterized.

Methods

We determined whether intrabronchial exposure to LPS causes concomitant release of HBP and IL-26 in human airways, and whether IL-26 can enhance LPS-induced release of HBP in isolated human neutrophils.

Results

We found that the concentration of HBP was markedly increased in bronchoalveolar lavage (BAL) fluid 12, 24, and 48 hours after LPS exposure, and that it displayed a strong and positive correlation with that of IL-26. Moreover, the concentration of HBP in conditioned media from isolated neutrophils was enhanced only after co-stimulation with LPS and IL-26.

Conclusions

Taken together, our findings indicate that TLR4 stimulation causes concomitant release of HBP and IL-26 in human airways, and that IL-26 may constitute a required co-stimulant for HBP release in neutrophils, thus enabling the concerted action of HBP and IL-26 in local host defense.

Heparin-Binding Protein in Bronchoalveolar Lavage Fluid as a Biomarker for Discriminating Severe Bacterial and Viral Pneumonia in Critically Ill Children

Objective

This study is aimed at exploring the ability to use heparin-binding protein (HBP) in bronchoalveolar lavage fluid (BALF) to differentially diagnose bacterial infection from viral infection for severe community-acquired pneumonia (CAP) in critically ill children.

Methods

A total of 181 children with severe CAP admitted to the intensive care unit (ICU) were included in this study. BALF and blood samples were collected within the first 24 hours of admission. BALF HBP and interleukin-6 (IL-6) concentrations and neutrophil percentage (N%) as well as blood HBP, IL-6, procalcitonin (PCT), C-reactive protein, white blood cell concentrations and N% were measured.

Results

Of the enrolled children, 126 were confirmed to have bacterial pneumonia, and 55 were confirmed to have viral pneumonia. Blood HBP and PCT concentrations and N% and BALF HBP and IL-6 concentrations and N% were significantly higher in bacterial pneumonia than in viral pneumonia (P < 0.05). In the bacterial pneumonia group, HBP and IL-6 concentrations and N% in BALF samples were all significantly higher than those in blood samples (P < 0.001), and BALF HBP and IL-6 concentrations and N% were correlated with blood HBP and IL-6 concentrations and N%, respectively (r = 0.439, 0.250, and 0.235, P < 0.01). BALF N% and blood N% were both correlated with BALF HBP concentrations and blood HBP concentrations, respectively (r = 0.622 and 0.346, P < 0.001). ROC analysis revealed that BALF HBP showed the best ability to predict bacterial pneumonia, with an area under the curve of 0.994, a sensitivity of 95.24%, and a specificity of 100.00% at its optimal cutoff value of 74.05 ng/mL.

Conclusion

BALF HBP might be a promising biomarker for the early discrimination of bacterial infection from viral infection in critically ill children with severe CAP.

Cytokines in Lung Transplantation

Lung transplantation has developed significantly in recent years, but post-transplant care and patients' survival still need to be improved. Moreover, organ shortage urges novel modalities to improve the quality of unsuitable lungs. Cytokines, the chemical mediators of the immune system, might be used for diagnostic and therapeutic purposes in lung transplantation. Cytokine monitoring pre- and post-transplant could be applied to the prevention and early diagnosis of injurious inflammatory events including primary graft dysfunction, acute cellular rejection, bronchiolitis obliterans syndrome, restrictive allograft syndrome, and infections. In addition, preoperative cytokine removal, specific inhibition of proinflammatory cytokines, and enhancement of anti-inflammatory cytokines gene expression could be considered therapeutic options to improve lung allograft survival. Therefore, it is essential to describe the cytokines alteration during inflammatory events to gain a better insight into their role in developing the abovementioned complications. Herein, cytokine fluctuations in lung tissue, bronchoalveolar fluid, peripheral blood, and exhaled breath condensate in different phases of lung transplantation have been reviewed; besides, cytokine gene polymorphisms with clinical significance have been summarized.

Markers of rejection of a lung allograft: state of the art

Chronic lung allograft dysfunction (CLAD) affects approximately 50% of all lung transplant recipients by 5 post-operative years and is the leading cause of death in lung transplant recipients. Early CLAD diagnosis or ideally prediction of CLAD is essential to enable early intervention before significant lung injury occurs. New technologies have emerged to facilitate biomarker discovery, including epigenetic modification and single-cell RNA sequencing. This review examines new and existing technologies for biomarker discovery and the current state of research on biomarkers for identifying lung transplant rejection.

Diagnostic Value of Serum Heparin Binding Protein, Blood Lactic Acid Combined with hs-CRP in Sepsis and Its Relationship with Prognosis

OBJECTIVE

To explore the diagnostic value of serum heparin binding protein (HBP), blood lactic acid (Lac) combined with high-sensitivity C- reactive protein (hs-CRP) in sepsis and its relationship with prognosis.

METHODS

The clinical data of 127 patients with sepsis from March 2019 to March 2021 in our hospital were retrospectively analyzed. 120 outpatients undergoing physical examination in the same period in our hospital were selected as the control group. According to the severity of the disease, 127 sepsis patients were divided into the mild sepsis group (n = 45), severe sepsis group (n = 53), and septic shock group (n = 29). According to the clinical prognosis, the patients were divided into the survival group (n = 96) and death group (n = 31). Serum HBP, Lac, and hs-CRP levels were measured in all subjects. The ROC curves of the subjects were drawn to analyze the predictive value of serum HBP, Lac, and hs-CRP for the prognosis of sepsis patients.

RESULTS

The levels of serum HBP, Lac, and hs-CRP in the sepsis group were higher than those in the control group (P < 0.05). With the increase of the severity of sepsis, serum HBP, Lac, and hs-CRP levels of patients gradually increased (P < 0.05). The levels of serum HBP, Lac, and hs-CRP in the death group were higher than those in the survival group (P < 0.05). The AUC of serum HBP, Lac, and hs-CRP for predicting the prognosis of sepsis patients was 0.858 (95% CI: 0.763-0.953), 0.694 (95% CI: 0.589-0.799), and 0.843 (95% CI: 0.759-0.927). The AUC of serum HBP, Lac combined with hs-CRP for predicting the prognosis of sepsis patients was 0.961 (95% CI: 0.000-1.000).

CONCLUSION

The levels of serum HBP, Lac, and hs-CRP in patients with sepsis were significantly increased and increased with the severity of sepsis. Serum HBP, Lac, and hs-CRP have a good value in predicting the prognosis of patients with sepsis and worthy of clinical application.

Heparin-binding protein in lower airway samples as a biomarker for pneumonia

Objectives

Ventilator-associated pneumonia (VAP) is difficult to diagnose using clinical criteria and no biomarkers have yet been proved to be sufficiently accurate. The use of the neutrophil-derived Heparin-binding protein (HBP) as a biomarker for pneumonia was investigated in this exploratory case–control study in two intensive care units at a tertiary referral hospital.

Methods

Patients with clinical signs of pneumonia were recruited and bronchoalveolar lavage fluid (BALF) or bronchial wash (BW) samples were collected. Mechanically ventilated and lung healthy subjects were recruited as controls. HBP was measured with enzyme-linked immunosorbent assay.

Results

BALF was collected from 14 patients with pneumonia and 14 healthy controls. Median HBP in BALF pneumonia samples was 14,690 ng/ml and controls 16.2 ng/ml (p < 0.0001). BW was collected from 10 pneumonia patients and 10 mechanically ventilated controls. Median HBP in BW pneumonia was 9002 ng/ml and controls 7.6 ng/ml (p < 0.0001).

Conclusions

These data indicate that HBP concentrations is significantly higher in lower airway samples from patients with pneumonia than control subjects and is a potentially useful biomarker for diagnosis of VAP.

Divergent airway microbiomes in lung transplant recipients with or without pulmonary infection

BACKGROUND

Lung transplant (LTx) recipients are at increased risk for airway infections, but the cause of infection is often difficult to establish with traditional culture-based techniques. The objectives of the study was to compare the airway microbiome in LTx patients with and without ongoing airway infection and identify differences in their microbiome composition.

METHODS

LTx recipients were prospectively followed with bronchoalveolar lavage (BAL) during the first year after transplantation. The likelihood of airway infection at the time of sampling was graded based on clinical criteria and BAL cultures, and BAL fluid levels of the inflammatory markers heparin-binding protein (HBP), IL-1β and IL-8 were determined with ELISA. The bacterial microbiome of the samples were analysed with 16S rDNA sequencing and characterized based on richness and evenness. The distance in microbiome composition between samples were determined using Bray-Curtis and weighted and unweighted UniFrac.

RESULTS

A total of 46 samples from 22 patients were included in the study. Samples collected during infection and samples with high levels of inflammation were characterized by loss of bacterial diversity and a significantly different species composition. Burkholderia, Corynebacterium and Staphylococcus were enriched during infection and inflammation, whereas anaerobes and normal oropharyngeal flora were less abundant. The most common findings in BAL cultures, including Pseudomonas aeruginosa, were not enriched during infection.

CONCLUSION

This study gives important insights into the dynamics of the airway microbiome of LTx recipients, and suggests that lung infections are associated with a disruption in the homeostasis of the microbiome.

Increased levels of HE4 (WFDC2) in systemic sclerosis: a novel biomarker reflecting interstitial lung disease severity?

Background:

Human epididymis protein 4 (HE4, also known as WFDC-2) has been implicated in fibrotic disorders pathobiology. We tested the hypothesis that HE4 may be used as a candidate biomarker for systemic sclerosis (SSc)-related interstitial lung disease (SSc-ILD).

Methods:

A total of 169 consecutive SSc patients and 169 age-and sex-matched healthy controls were enrolled and blood samples were collected. Pulmonary function tests (PFTs) and paired lavage was performed on 169 patients and 37 healthy controls. All patients were classified as having SSc-no ILD or SSc-ILD, based on high-resolution computed tomography (CT) scans of the chest, and a semiquantitative grade of ILD extent was evaluated through CT scans (grade 1, 0–25%; grade 2, 26–50%; grade 3, 51–75%; grade 4, 76–100%). Serum and bronchoalveolar lavage fluid (BALF) HE4 levels were measured by enzyme-linked immunosorbent assay.

Results:

Serum HE4 levels were higher in SSc patients [median (interquartile range), 139.4 (85.9–181.8) pmol/l] compared with healthy controls [39.5 (24.3–54.2) pmol/l, p < 0.001] and were higher in patients with SSc-ILD [172.1 (94.8–263.3) pmol/l] than in those with SSc-no ILD [97.4 (85.5–156.5) pmol/l, p < 0.001]. This observation was replicated in the BALF samples. Corresponding values were 510.8 (144.6–1013.8) pmol/l for SSc cohort, 754.4 (299–1060) pmol/l for SSc-ILD, 555.1 (203.7–776.2) pmol/l for SSc-no ILD, and 238.7 (97.7–397.6) pmol/l for controls. The semiquantitative grade of ILD on CT scan was significantly proportional to the HE4 levels and the lung function parameter (i.e., FVC) had a negative correlation with the HE4 levels.

Conclusion:

This is the first study to demonstrate the potential clinical utility of blood and BALF HE4 as a biomarker for SSc-ILD. Future prospective validation studies are warranted.

Heparin-Binding Protein as a Prognostic Biomarker of Sepsis and Disease Severity at the Emergency Department

OBJECTIVE

Rapid and early detection of patients at risk to develop sepsis remains demanding. Heparin-binding protein (HBP) has previously demonstrated good prognostic properties in detecting organ dysfunction among patients with suspected infections. This study aimed to evaluate the plasma levels of HBP as a prognostic biomarker for infection-induced organ dysfunction among patients seeking medical attention at the emergency department.

DESIGN

Prospective, international multicenter, convenience sample study.

SETTING

Four general emergency departments at academic centers in Sweden, Switzerland, and Canada.

PATIENTS

All emergency encounters among adults where one of the following criteria were fulfilled: respiratory rate >25 breaths per minute; heart rate >120 beats per minute; altered mental status; systolic blood pressure <100 mm Hg; oxygen saturation <90% without oxygen; oxygen saturation <93% with oxygen; reported oxygen saturation <90%.

INTERVENTION

None.

MEASUREMENTS AND MAIN RESULTS

A total of 524 emergency department patients were prospectively enrolled, of these 236 (45%) were eventually adjudicated to have a noninfectious disease. Three hundred forty-seven patients (66%) had or developed organ dysfunction within 72 h, 54 patients (10%) were admitted to an intensive care unit, and 23 patients (4%) died within 72 h. For the primary outcome, detection of infected-related organ dysfunction within 72 h, the area under the receiver operating curve (AUC) for HBP was 0.73 (95% CI 0.68-0.78) among all patients and 0.82 (95% CI 0.76-0.87) among patients confidently adjudicated to either infection or no infection. Against the secondary outcome, infection leading to admittance to the ICU, death or a persistent high SOFA-score due to an infection (SOFA-score ≥5 at 12-24 h) HBP had an AUC of 0.87 (95% CI 0.79-0.95) among all patients and 0.88 (95% CI 0.77-0.99) among patients confidently adjudicated to either infection or noninfection.

CONCLUSIONS

Among patients at the emergency department, HBP demonstrated good prognostic and discriminatory properties in detecting the most severely ill patients with infection.

Heparin-Binding Protein: A Novel Biomarker Linking Four Different Cardiovascular Diseases

Cardiovascular diseases are an important group of diseases that seriously affect quality of life. Thus, their treatment warrants further study. Heparin-binding protein (HBP) is a granulocyte protein derived from neutrophils. When an infection occurs, neutrophils release HBP, which can lead to elevated HBP levels in the blood. Therefore, HBP family members are said to be important indicators of infection. However, basic evidence is still lacking to confirm the possible relationship between HBP and cardiovascular diseases. Using bioinformatics methods, we investigated the role of the HBP network in normal hearts and hearts from patients with cardiovascular disease. First, we used the Open Targets database to obtain a list of HBP-encoding mRNAs related to atherosclerosis, myocarditis, myocardial infarction, and myocardial ischemia. Then, we constructed an HBP gene interaction network map using STRING. Clustering coefficients were calculated using Cytoscape, and MCODE was used for subnet analysis. Finally, the proposed interstitial network of HBPs was established and analyzed by Metascape enrichment analysis of the relevant signaling pathways. The aggregation coefficient of the HBP interaction network was higher among hearts with the four cardiovascular diseases, atherosclerosis (0.496), myocarditis (0.631), myocardial infarction (0.532), and myocardial ischemia (0.551), than in normal hearts. Metascape analysis showed that "NABA_MATRISOME_ASSOCIATED" was a typical pathway with the highest p value associated with epithelialization in all four diseases. Moreover, a large number of important HBPs were identified that may be significant for the treatment of these diseases. Therefore, HBPs do have a highly atopic connectivity network in cardiovascular diseases, and specific HBPs or signaling pathways may be used as targets for the development of new treatments for cardiovascular diseases.

Lung allograft donors with excessive alcohol use have increased levels of human antimicrobial peptide LL-37

The relatively low long-term survival rate of lung transplant recipients as compared to other organ recipients serves as an impetus to identify potential lung dysfunction as early as possible. There is an association between donor heavy alcohol use and acute lung injury in the lung allograft after transplant, known as primary graft dysfunction. Excessive alcohol use (EAU) can induce pulmonary immune dysregulation in response to an infection. Antimicrobial peptides (AMPs) are an important component of the innate immune response to pulmonary infections, but the impact of EAU on AMPs in the allograft lung has not been evaluated. Our hypothesis is that specific lung AMPs, LL-37, α-defensin-1,2,3, and β-defensin-2, are dysregulated in the lungs from organ donors who had EAU. In this prospective observational investigation, we measured AMPs via ELISA and inflammatory cytokines via multiplex bead array, in bronchoalveolar lavage (BAL) fluid of lung allograft donors, comparing results based on their alcohol consumption. LL-37 levels in lung donors with EAU were found to be increased compared to nondrinker (ND) donors [median 7.7 ng/mL (IQR 4.1-37.0) vs. 2.3 ng/mL (IQR 1.1-7.9), p = 0.004], whereas α-defensins-1,2,3 were decreased only in the presence of an infection in donors with EAU compared to ND donors [median 2.2 ng/mL (IQR 1.6-2.4) vs. 3.2 ng/mL (IQR 2.3-3.8), p = 0.049]. There was no difference in β-defensin-2 levels. Gene expression levels of these AMPs were not different. Elevated levels of CXCL8 were noted in bronchial washings of donors with EAU compared to ND donors, [median 4372 pg/mL (IQR 3352-13180) vs. 867.3 pg/mL (IQR 163.6-3675), p = 0.04], suggesting a potentially heightened inflammatory response. At 1 month post-transplant, LL-37 and CXCL8 levels are decreased compared to levels at time of transplant. In lung donors with EAU, LL-37 and α-defensins-1,2,3 dysregulated levels in the presence of an infection may be a harbinger of dysfunction of the lungs through the transplant process.

Biomarkers in Stress Related Diseases/Disorders: Diagnostic, Prognostic, and Therapeutic Values

Various internal and external factors negatively affect the homeostatic equilibrium of organisms at the molecular to the whole-body level, inducing the so-called state of stress. Stress affects an organism's welfare status and induces energy-consuming mechanisms to combat the subsequent ill effects; thus, the individual may be immunocompromised, making them vulnerable to pathogens. The information presented here has been extensively reviewed, compiled, and analyzed from authenticated published resources available on Medline, PubMed, PubMed Central, Science Direct, and other scientific databases. Stress levels can be monitored by the quantitative and qualitative measurement of biomarkers. Potential markers of stress include thermal stress markers, such as heat shock proteins (HSPs), innate immune markers, such as Acute Phase Proteins (APPs), oxidative stress markers, and chemical secretions in the saliva and urine. In addition, stress biomarkers also play critical roles in the prognosis of stress-related diseases and disorders, and therapy guidance. Moreover, different components have been identified as potent mediators of cardiovascular, central nervous system, hepatic, and nephrological disorders, which can also be employed to evaluate these conditions precisely, but with stringent validation and specificity. Considerable scientific advances have been made in the detection, quantitation, and application of these biomarkers. The present review describes the current progress of identifying biomarkers, their prognostic, and therapeutic values.

Biomarkers in Stress Related Diseases/Disorders: Diagnostic, Prognostic, and Therapeutic Values

Various internal and external factors negatively affect the homeostatic equilibrium of organisms at the molecular to the whole-body level, inducing the so-called state of stress. Stress affects an organism's welfare status and induces energy-consuming mechanisms to combat the subsequent ill effects; thus, the individual may be immunocompromised, making them vulnerable to pathogens. The information presented here has been extensively reviewed, compiled, and analyzed from authenticated published resources available on Medline, PubMed, PubMed Central, Science Direct, and other scientific databases. Stress levels can be monitored by the quantitative and qualitative measurement of biomarkers. Potential markers of stress include thermal stress markers, such as heat shock proteins (HSPs), innate immune markers, such as Acute Phase Proteins (APPs), oxidative stress markers, and chemical secretions in the saliva and urine. In addition, stress biomarkers also play critical roles in the prognosis of stress-related diseases and disorders, and therapy guidance. Moreover, different components have been identified as potent mediators of cardiovascular, central nervous system, hepatic, and nephrological disorders, which can also be employed to evaluate these conditions precisely, but with stringent validation and specificity. Considerable scientific advances have been made in the detection, quantitation, and application of these biomarkers. The present review describes the current progress of identifying biomarkers, their prognostic, and therapeutic values.

Bronchoalveolar lavage cytokines are of minor value to diagnose complications following lung transplantation

Early diagnosis and treatment of acute cellular rejection (ACR) may improve long-term outcome for lung transplant recipients (LTRs). Cytokines have become valuable diagnostic tools in many medical fields. The role of bronchoalveolar lavage (BAL) cytokines is of unknown value to diagnose ACR and distinguish rejection from infection. We hypothesized that distinct cytokine patterns obtained by surveillance bronchoscopies during the first year after transplantation are associated with ACR and microbiologic findings.

We retrospectively analyzed data from 319 patients undergoing lung transplantation at University Hospital Zurich from 1998 to 2016. We compared levels of IL-6, IL-8, IFN-γ and TNF-α in 747 BAL samples with transbronchial biopsies (TBB) and microbiologic results from surveillance bronchoscopies. We aimed to define reference values that would allow distinction between four specific groups “ACR”, “infection”, “combined ACR and infection” and “no pathologic process”. No definitive pattern was identified. Given the overlap between groups, these four cytokines are not suitable diagnostic markers for ACR or infection after lung transplantation.

Clinical Efficacy and Safety of Mechanical Ventilation Combined with Fiberoptic Bronchoalveolar Lavage in Patients with Severe Pulmonary Infection

Background

The aim of this study was to assess the clinical efficacy and safety of mechanical ventilation combined with fiberoptic bronchoalveolar lavage in patients with severe pulmonary infection.

Material/Methods

We randomly divided 81 patients with severe pulmonary infection into a control group (n=40) and an observation group (n=41). Both groups were treated using mechanical ventilation, and observation group additionally received assistive fiberoptic bronchoalveolar lavage.

Results

The cure rate and effectiveness rate in the observation group were higher than in the control group (P<0.05, χ²=3.2), and the incidence of ventilator-associated pneumonia in the observation group was significantly lower than that in the control group (P<0.05, χ²=9.4). The partial pressure of oxygen (PaO₂) and oxygen saturation (SaO₂) were higher in the observation group than in the control group (P<0.05, t=3.862, t=33.595), whereas the partial pressure of carbon dioxide (PaCO₂) and respiratory rate were lower in the observation group than in the control group (P<0.05, t=3.307, t=5.043). The levels of C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-8 (IL-8) in the 2 groups were lower after treatment than before treatment (all P<0.05), and the levels in the observation group were lower than those in the control group (all P<0.05). Hospital stay, infection control window appearance time, invasive mechanical ventilation time, and total mechanical ventilation time in the observation group were shorter than those in the control group (P<0.05, t=13.990, t=8.643, t=9.717, t=8.980).

Conclusions

Mechanical ventilation combined with fiberoptic bronchoalveolar lavage can effectively improve the curative effects and the blood gas and inflammation indicators in patients.

Cytokine profile in lung transplant recipients with Aspergillus spp colonization

We studied cytokine profiles in BAL of LTRs with Aspergillus spp colonization who did not progress to IPA in the absence of antifungal prophylaxis. This was a retrospective, single center case-control study. BAL samples were analyzed for cytokines. Patients with Aspergillus spp in BAL who did not receive prophylaxis and did not develop IPA were compared to LTRs with Aspergillus spp that received prophylaxis, LTRs with IPA and controls. Twenty-one patients with Aspergillus colonization who did not develop IPA, seven patients with suspected IPA who received prophylaxis, 4 IPA and 19 controls were included. IPA group had significantly higher levels (median [IQR]) of MIP-1 beta compared to the Suspected IPA group (5 vs 5 P: 0.03). The Suspected IPA group had significantly higher levels of IL-12 (11.38 vs 1 P: 0.0001), IL-1 RA (86.11 vs 23.98 P: 0.0118), IP-10 (22.47 vs 0.86 P: 0.0151), HGF (40.92 vs 16.82 P: 0.0055), and MIG (169.62 vs 5 P: 0.0005) than Colonization group. We have identified a unique cytokine signature in patients with Aspergillus colonization that do not develop IPA. Our study forms basis for a larger study to use these cytokines profile to identify patients at a lower risk of developing IPA.

Significance of Heparin-Binding Protein and D-dimers in the Early Diagnosis of Spontaneous Bacterial Peritonitis

Objectives

Ascites and spontaneous bacterial peritonitis (SBP) are among the most important complications of decompensated liver cirrhosis. In clinical practice, new inflammation biomarkers are needed for the early diagnosis of SBP, as well-known biomarkers, such as C-reactive protein (CRP), procalcitonin (PCT), or peripheral blood white blood cell (WBC) count, lack the required specificity and sensitivity. The aim of the study was to evaluate the significance of heparin-binding protein (HBP) in comparison to CRP, PCT, WBC, and D-dimers in the diagnosis of SBP.

Design

Cross-sectional descriptive single-center study.

Setting

Department of Infectious and Tropical Diseases and Hepatology, Medical University of Warsaw, Poland.

Patients

All patients admitted to the aforementioned department with decompensated liver cirrhosis and ascites between February 1, 2016, and June 30, 2017.

Intervention

Several markers (HBP, CRP, PCT, WBC, and D-dimers) were analysed in blood serum in regard to their potential use in the diagnosis of SBP in patients with decompensated liver cirrhosis and ascites. We correlated the levels of the aforementioned markers with an ascitic fluid polymorphonuclear count using simple linear regression and multiple linear regression. Sensitivities, specificities, and positive and negative predictive values for SBP were calculated for the aforementioned makers of inflammation.

Measurements and Main Results

A total of 63 patients with decompensated liver cirrhosis and ascites participated in the study. The etiology of liver cirrhosis was varied (HCV: n = 40, HBV: n = 13, HCV/HBV: n = 4, AIH: n = 3, PBC: n = 2, and haemochromatosis: n = 1). After the peritoneal tap, 31 patients were determined to have SBP (defined as an ascitic fluid polymorphonuclear count > 250 cells/μL) and 32 patients had no evidence of SBP on peritoneal tap. A very weak, but statistically significant, correlation of HBP, WBC, and D-dimer levels with the peritoneal fluid polymorphonuclear (PMN) count was observed in the simple regression model, but multivariable analysis using the multiple regression model showed that only D-dimers correlated with peritoneal fluid PMNs independently from other inflammation biomarkers. A D-dimer cutoff value of 1500 ng/mL was determined optimal for ruling out SBP due to high sensitivity (96.8%) and a high negative predictive value (92.9%), although predictably, this marker was not useful for confirming SBP due to low specificity (40.6%) and a low positive predictive value (61.2%). The usefulness of D-dimers was limited by the fact that only 22.2% of the studied patients had D-dimer levels below 1500 ng/mL. HBP and WBC showed little to no predictive value in this study.

Conclusions

D-dimers < 1500 ng/mL make the diagnosis of SBP unlikely, although the peritoneal tap is still the reference method in such situations. In the studied group, the determination of HBP was of no diagnostic benefit in the diagnosis of SBP.

Heparin-binding protein in sputum as a marker of pulmonary inflammation, lung function, and bacterial load in children with cystic fibrosis

Background

Cystic fibrosis (CF) is associated with bacterial pulmonary infections and neutrophil-dominated inflammation in the airways. The aim of this study was to evaluate the neutrophil-derived protein Heparin-binding protein (HBP) as a potential sputum marker of airway inflammation and bacterial load.

Methods

Nineteen CF patients, aged 6–18 years, were prospectively followed for 6 months with sputum sampling at every visit to the CF clinic. A total of 41 sputum samples were collected. Sputum-HBP was analysed with ELISA, neutrophil elastase activity with a chromogenic assay, and total bacterial load with RT-PCR of the 16 s rDNA gene. Data were compared to lung function parameters and airway symptoms.

Results

HBP and elastase correlated to a decrease in FEV₁%predicted compared to the patients´ individual baseline pulmonary function (∆FEV₁), but not to bacterial load. Area under the receiver operating characteristic curve values for the detection of > 10% decrease in ∆FEV₁ were 0.80 for HBP, 0.78 for elastase, and 0.54 for bacterial load.

Conclusions

Sputum HBP is a promising marker of airway inflammation and pulmonary function in children with CF.

Lung injury caused by paraquat poisoning results in increased interleukin-6 and decreased microRNA-146a levels

The aim of the present study was to investigate the expression of microRNA (miR)-146a in the pulmonary macrophages, peripheral blood mononuclear cells and serum of patients with lung injury caused by paraquat poisoning, as well as the underlying mechanism of its regulation in the disease. A total of 26 patients with lung injury caused by paraquat poisoning were included in the present study. In addition, 33 healthy subjects were included as the control group. The expression levels of interleukin (IL)-6 mRNA and miR-146a was determined by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Western blotting was used to measure IL-6 protein expression, while enzyme-linked immunosorbent assay was also performed to determine the secretion of IL-6 protein. A dual-luciferase reporter assay was conducted to examine whether IL-6 mRNA is a direct target of miR-146a. Patients with lung injury caused by paraquat poisoning exhibited higher IL-6 mRNA and protein levels as compared with those in healthy subjects. In addition, miR-146a expression in patients with paraquat poisoning-induced lung injury was significantly reduced in comparison with that in healthy subjects. Notably, the overexpression of miR-146a by mimic transfection downregulated the expression of IL-6 in pulmonary macrophages. The results of dual-luciferase reporter assay demonstrated that IL-6 mRNA was a direct target of miR-146a. Therefore, the present study demonstrated that increased expression of IL-6 in patients with lung injury caused by paraquat poisoning is associated with decreased expression of miR-146a. Furthermore, miR-146a may regulate the occurrence and immune response of lung injury caused by paraquat poisoning and this process is possibly achieved via IL-6, an important cytokine that mediates inflammation.

Heparin-binding protein, lysozyme, and inflammatory cytokines in bronchoalveolar lavage fluid as diagnostic tools for pulmonary infection in lung transplanted patients

Pulmonary infection is a common complication after lung transplantation, and early detection is crucial for outcome. However, the condition can be clinically difficult to diagnose and to distinguish from rejection. The aim of this prospective study was to evaluate heparin-binding protein (HBP), lysozyme, and the cytokines interleukin (IL)-1β, IL-6, IL-8, IL-10 and tumor necrosis factor (TNF) in bronchoalveolar lavage fluid (BALF) as potential biomarkers for pulmonary infection in lung-transplanted patients. One hundred thirteen BALF samples from 29 lung transplant recipients were collected at routine scheduled bronchoscopies at 3 and 6 months, or on clinical indication. Samples were classified into no, possible, probable, or definite infection at the time of sampling. Rejection was defined by biopsy results. HBP, lysozyme, and cytokines were analyzed in BALF and correlated to likelihood of infection and rejection. All biomarkers were significantly increased in BALF during infection, whereas patients with rejection presented low levels that were comparable to noninfection samples. HBP, IL-1β, and IL-8 were the best diagnostic markers of infection with area under the receiver-operating characteristic curve values of 0.88, 0.91, and 0.90, respectively. In conclusion, HBP, IL-1β, and IL-8 could be useful diagnostic markers of pulmonary infection in lung-transplanted patients.