Interleukin-8 and markers of neutrophil degranulation in pleural effusions

Influence of Malignant Pleural Fluid from Lung Adenocarcinoma Patients on Neutrophil Response

Simple Summary

This study provides novel information about the role of neutrophils in malignant pleural effusion (MPE) and hallmarks their clinical relevance. Since these cells have emerged as important regulators of cancer, we characterized their phenotype and functions in MPE microenvironment. We found that neutrophil-derived products (degranulation molecules and neutrophil extracellular traps (NETs)) were increased in MPE. In addition, NETs were associated with a worse outcome in lung adenocarcinoma patients with MPE.

Abstract

Malignant pleural effusion (MPE) is a common severe complication of advanced lung adenocarcinoma (LAC). Neutrophils, an essential component of tumor infiltrates, contribute to tumor progression and their counts in MPE have been associated with worse outcome in LAC. This study aimed to evaluate phenotypical and functional changes of neutrophils induced by MPE to determine the influence of MPE immunomodulatory factors in neutrophil response and to find a possible association between neutrophil functions and clinical outcomes. Pleural fluid samples were collected from 47 LAC and 25 heart failure (HF) patients. We measured neutrophil degranulation products by ELISA, oxidative burst capacity and apoptosis by flow cytometry, and NETosis by fluorescence. The concentration of degranulation products was higher in MPE-LAC than in PE-HF. Functionally, neutrophils cultured with MPE-LAC had enhanced survival and neutrophil extracellular trap (NET) formation but had reduced oxidative burst capacity. In MPE, NETosis was positively associated with MMP-9, P-selectin, and sPD-L1 and clinically related to a worse outcome. This is the first study associating NETs with a worse outcome in MPE. Neutrophils likely contribute to tumor progression through the release of NETs, suggesting that they are a potential therapeutic target in LAC.

Pleural Fluid Cytokine Levels at Baseline and Over Time are Associated With Time to IPC Removal: An Exploratory Study

BACKGROUND

The behavior of pleural fluid cytokine (PFCs) levels and their association with pleurodesis after indwelling pleural catheter (IPC) placement is unknown.

OBJECTIVE

A prospective exploratory study was conducted to obtain preliminary data on PFC levels after IPC placement.

METHODS

The PFC panel consisted of 4 cytokines [interleukin -8 (IL-8), vascular endothelial growth factor, total (but not activated) transforming growth factor betas, and basic fibroblast growth factor], measured across 5 time points (T0: insertion; T1: 24 to 48 h; T2: 72 to 96 h; T3: 1 wk; and T4: 2 wk). Profile plots were used to identify patterns of change of PFC levels. Correlation matrices for each PFC over time were computed, and area under the curve (AUC) categories were used to compare the cumulative incidence of IPC removal. Auto pleurodesis was defined as elective catheter removal because of decreased drainage within 90 days of insertion.

RESULTS

A total of 22 patients provided complete data. Except for IL-8, the majority of PFCs demonstrated strong positive correlations across measurement time points. Patients with high AUCs for IL-8, basic fibroblast growth factor, and vascular endothelial growth factor had a higher cumulative incidence of IPC removal by 90 days than did patients with low AUCs.

CONCLUSION

This is the first study to evaluate longitudinal changes of pleural cytokine levels with respect to the likelihood of IPC removal and provide early evidence that the cytokine profile may be associated with the outcome of pleurodesis induced by IPCs. However, this is an exploratory study and further studies are needed to assess if these findings can be validated in further studies.

Predictive Value of Pleural Cytology in the Diagnosis of Complicated Parapneumonic Effusions and Empyema Thoracis

Introduction

Complicated parapneumonic effusions (CPE) are distinguished from uncomplicated parapneumonic effusions (UPE) by the ability to resolve without drainage. Determinants include pleural pH, pleural glucose, and pleural LDH, along with microbiologic cultures. Inflammation mediated by neutrophil chemotactic cytokines leads to fibrinous loculation of an effusion, and the degree of this inflammation may lead to a CPE. One role of the pathologist is to evaluate for the presence of malignancy in a pleural effusion; however, the ability of the pathologist to distinguish a CPE from UPE has not been evaluated.

Materials and Methods

A single-center retrospective study was performed on pleural cytology specimens from 137 patients diagnosed with a parapneumonic effusion or empyema over a five-year interval. Pleural cytology was characterized as either uncomplicated or complicated by two pathologists based on cellular composition and the presence or absence of fibrinous exudate in the fluid. Cohen's kappa was calculated for interobserver agreement. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of cytologic diagnoses were calculated. Determinants of cytologic accuracy were assessed using Wilcoxon rank sum test, unpaired t-test, and logistic regression.

Results

Kappa interobserver agreement between pathologists was 0.753. Pleural fluid cytology sensitivity, specificity, PPV, and NPV for CPE/empyema were 76.0%, 95% CI [65.0, 84.9]; 50%, 95% CI [29.1, 70.9]; 83.3%, 95% CI [76.7, 88.4]; and 38.7%, 95% CI [26.5, 52.5], respectively. The presence of pleural bacteria, elevated pleural LDH, and reduced pleural pH were nonsignificant determinants of cytologic accuracy. Logistic regression was significant for the presence of pleural bacteria (p = 0.03) in determining a successful cytologic diagnosis.

Conclusion

Pleural cytology adds little value to traditional markers of distinguishing a UPE from CPE. Inflammation on pleural fluid cytology is suggestive of empyema or the presence of pleural fluid bacteria.

Frontline Science: Aggregated neutrophil extracellular traps prevent inflammation on the neutrophil-rich ocular surface

Eye rheum is a physiological discharge, which accumulates at the medial angle of the healthy eye soon after opening in the morning. Microscopic evaluation of eye rheum revealed the presence of viable neutrophils, bacteria, epithelial cells, and particles, aggregated by neutrophil extracellular traps. We observed that in the evening, during eye closure, high C5a recruited neutrophils to the tear film and activated them. In this hypoxic area rich in CO₂ , neutrophils fight microbial aggressors by degranulation. Immediately after eye opening, the microenvironment of the ocular surface changes, the milieu gets normoxic, and loss of CO₂ induces subtle alkalinization of tear film. These conditions favored the formation of neutrophil extracellular traps (NETs) that initially covers the ocular surface and tend to aggregate by eyelid blinking. These aggregated neutrophil extracellular traps (aggNETs) are known as eye rheum and contain several viable neutrophils, epithelial cells, dust particles, and crystals packed together by NETs. Similar to aggNETs induced by monosodium urate crystals, the eye rheum shows a robust proteolytic activity that degraded inflammatory mediators before clinically overt inflammation occur. Finally, the eye rheum passively floats with the tear flow to the medial angle of the eye for disposal. We conclude that the aggNETs-based eye rheum promotes cleaning of the ocular surface and ameliorates the inflammation on the neutrophil-rich ocular surfaces.

Heightened Systemic Levels of Neutrophil and Eosinophil Granular Proteins in Pulmonary Tuberculosis and Reversal following Treatment

Granulocytes are activated during Mycobacterium tuberculosis infection and act as immune effector cells, and granulocyte responses are implicated in tuberculosis (TB) pathogenesis. Plasma levels of neutrophil and eosinophil granular proteins provide an indirect measure of degranulation. In this study, we wanted to examine the levels of neutrophil and eosinophil granular proteins in individuals with pulmonary tuberculosis (PTB) and to compare them with the levels in individuals with latent TB (LTB). Hence, we measured the plasma levels of myeloperoxidase (MPO), neutrophil elastase, proteinase 3, major basic protein (MBP), eosinophil-derived neurotoxin (EDN), eosinophil cationic protein (ECP), and eosinophil peroxidase (EPX) in these individuals. Finally, we also measured the levels of all of these proteins in PTB individuals following antituberculosis treatment (ATT). Our data reveal that PTB individuals are characterized by significantly higher plasma levels of MPO, elastase, proteinase 3, as well as MBP and EDN in comparison to those in LTB individuals. Our data also reveal that ATT resulted in the reversal of all of these changes, indicating an association with TB disease. Finally, our data show that the systemic levels of MPO and proteinase 3 can significantly discriminate PTB from LTB individuals. Thus, our data suggest that neutrophil and eosinophil granular proteins could play a potential role in the innate immune response and, therefore, the pathogenesis of pulmonary TB.

Analysis of Cytokine Levers in Pleural Effusions of Tuberculous Pleurisy and Tuberculous Empyema

The aim is to examine whether the interleukin-1β (IL-1β), IL-2, IL-6, tumor necrosis factor-α (TNF-α), plasminogen activator inhibitor type-1 (PAI-1), and tissue plasminogen activator (t-PA) levels were different in pleural effusions of tuberculous pleurisy and tuberculous empyema. IL-1β, IL-2, IL-6, TNF-α, PAI-1, and t-PA levels in pleural fluids of 40 patients with tuberculous pleurisy and 38 patients with tuberculous empyema were measured. The levels of IL-1β, PAI-1, and t-PA in the pleural effusions were different between tuberculous pleurisy and tuberculous empyema; it could be helpful to differentiate the two diseases. The levels of PAI-1, IL-1β were higher and t-PA, IL-6 were lower in pleural effusions of the patients with tuberculous empyema and who must undergo operation than the patients who could be treated with closed drainage and anti-TB chemotheraphy. These indications may be helpful to evaluate whether the patient needs the operation.

Intrapleural Fibrinolysis with Urokinase Versus Alteplase in Complicated Parapneumonic Pleural Effusions and Empyemas: A Prospective Randomized Study

BACKGROUND

Pleurofibrinolysis has been reported to be potentially beneficial in the management of complicated parapneumonic effusions (CPPE) and empyemas in the adult population.

METHODS

Prospective, controlled, randomized, and double-blind study, to evaluate intrapleural alteplase 10 mg (initially 20 mg was considered but bleeding events forced dose reduction) versus 100,000 UI urokinase every 24 h for a maximum of 6 days in patients with CPPE or empyemas. The primary aim was to evaluate the success rate of each fibrinolytic agent at 3 and 6 days. Success of therapy was defined as the presence of both clinical and radiological improvement, making additional fibrinolytic doses unnecessary, and eventually leading to resolution. Secondary outcomes included the safety profile of intrapleural fibrinolytics, referral for surgery, length of hospital stay, and mortality.

RESULTS

A total of 99 patients were included, of whom 51 received alteplase and 48 urokinase. Success rates for urokinase and alteplase at 3 and 6 days were not significantly different, but when only the subgroup of CPPE was considered, urokinase resulted in a high proportion of cures. There were no differences in mortality or surgical need (overall, 3 %). Five (28 %) patients receiving 20 mg of alteplase and 4 (12 %) receiving 10 mg presented serious bleeding events.

CONCLUSIONS

If intrapleural fibrinolytics are intended to be used, urokinase may be more effective than alteplase in patients with non-purulent CPPE and have a lower rate of adverse events.

Prognostic value of pro-inflammatory cytokine and pro-angiogenesis factor in differentiating malignant from benign exudative effusion

BACKGROUND AND AIMS

The precise mechanism of pathogenesis in exudation of effusions is uncertain. Released factors in inflammation and malignancy of pleura are related to incremented permeability of the micro-pleural vessels. Angiopoietins (Ang) take part in development of angiogenesis and pleural inflammation. Interleukin-8 (IL-8) influences proliferation and tumor angiogenesis and it is expressed in cancer. The aims of this study were to investigate the relationship between inflammation, angiogenesis and etiologies of exudative effusions, and to evaluate the diagnostic value in differentiating malignant from benign.

METHODS

The study includes 49 pleural fluid (PF) samples. Ang-2 and IL-8 in PF and serum were estimated.

RESULTS

Ten patients were transudative and 39 patients were exudative fluid, subdivided into 16 benign and 23 malignant effusion. Ang-2 and IL-8 either fluid level or ratio were in significantly high in exudative more than in transudative fluid (P = 0.002). Ang-2 and IL-8 in PF were in high level than in serum of exudative and transudative. Ang-2 fluid level and ratio were significantly high in benign exudative effusion (P = 0.01, P = 0.05, respectively), while IL-8 level was significantly high in malignant exudative effusion (P = 0.04). Cut-off points for PF Ang-2 and IL-8 in differentiating malignant from benign exudative were 15.67 ng/mL, 325.54 pg/mL, respectively.

CONCLUSION

Our results support the evidence that angiogenesis and inflammatory pathways are linked, and that inflammation and vascular permeability of pleura constitutes the pathogenic basis of the majority of exudative effusion.

Utility of measurement of interleukin-1ß and interleukin-8 in the diagnosis of complicated parapneumonic pleural effusions

OBJECTIVES

Thirty percent of patients with pneumonia develop pleural effusion, and of these, 20% have complicated effusion (CPPE), which may require a chest tube or surgery for resolution. The objective of the study is to compare the diagnostic yield of determining interleukin-1β and interleukin-8 in pleural fluid (PF) (PFIL-1β and PFIL-8) with respect to classic criteria (pH <7.2, lactate dehydrogenase [LD] >1,000 IU/mL, and/or glucose <60 mg/dL) in the early diagnosis of CPPE.

METHODS

Of the 559 patients studied, 40 had CPPE. All underwent PF analysis: pH, glucose (PFGLUC), LD (PFLD), PFIL-1β and PFIL-8, and PF/serum ratios (PF/SIL-1β and PF/SIL-8).

RESULTS

The diagnostic criterion that showed the best area under the curve was the combination of PF/SIL-8 and PFIL-1β (0.906), with a statistically significant difference (P < .05) compared with the classic criterion of pH and PFGLUC or PFLD (0.826). The combination of PF/SIL-8 and PFIL-1β (cutoffs >5.73 and >9.14 pg/mL, respectively) was significantly more sensitive (72.7%) and more specific (97.9%) (P < .05) than the rest of the parameters used.

CONCLUSIONS

Measurement of IL-1β and IL-8 in pleural fluid may be useful in the early diagnosis of CPPE, although individually, it may not improve the results obtained with the PFLD. Further studies are needed to more firmly establish what role these new parameters can play in the diagnosis of CPPE.

Umbilical cord serum interleukin-6, C-reactive protein, and myeloperoxidase concentrations at birth and association with neonatal morbidities and long-term neurodevelopmental outcomes

OBJECTIVE

The aim of the study is to determine if umbilical cord serum concentrations of interleukin-6 (IL-6), C-reactive protein (CRP), and myeloperoxidase (MPO), in pregnancies at risk for preterm birth (PTB), are associated with neonatal morbidities and/or altered neurodevelopmental outcomes in the children.

STUDY DESIGN

Umbilical cord serum samples were collected at birth from 400 newborns delivered within a multicenter randomized controlled trial of repeated versus single course of antenatal corticosteroids (ACs), in women at increased risk for PTB. Newborns were followed through discharge and were evaluated between 36 and 42 months corrected age with neurological examination and Bayley Scales of Infant Development. Umbilical cord serum concentrations of IL-6, CRP, and MPO were determined using enzyme-linked immunoassays. Multivariate logistic regression analyses explored the relationship between umbilical cord serum IL-6, CRP, and MPO levels, adverse newborn outcomes, and PTB < 32 weeks of gestational age (GA).

RESULTS

Univariate analysis revealed that umbilical cord IL-6 above the 75th percentile was associated with increased respiratory distress syndrome (RDS) and chronic lung disease (CLD), but not with necrotizing enterocolitis (NEC), intraventricular hemorrhage (IVH), or neonatal sepsis; however, this association was not significant after adjusting for GA at delivery and treatment group. No significant associations between CRP or MPO and RDS, CLD, NEC, sepsis, or IVH were evident. Regression analysis revealed that CRP above the 75th percentile was associated with a decreased risk of CLD (odds ratio, 0.10; 95% confidence interval, 0.02-0.41). No associations between umbilical cord IL-6, CRP, or MPO and MDI < 70 or PDI < 70 were evident. Umbilical cord serum concentrations of IL-6, CRP, and MPO, above the 75th percentile, were associated with more frequent PTB < 32 weeks of GA.

CONCLUSION

Elevated umbilical cord serum concentration of CRP is associated with reduced risk for CLD even after adjusting for GA at delivery. Occurrence of levels > 75th percentile of IL-6, CRP, and MPO in umbilical cord serum was associated with PTB < 32 weeks of GA. Elevated umbilical cord serum concentrations of IL-6, CRP, and MPO at birth were not associated with poor neurodevelopmental outcomes.

Elastase, α1-proteinase inhibitor, and interleukin-8 in children and young adults with end-stage kidney disease undergoing continuous ambulatory peritoneal dialysis

Peritoneal dialysis is one of the main modality of treatment in end-stage kidney diseases (ESKD) in children. In our previous work in chronic kidney disease patients, in pre-dialyzed period and on hemodialysis, the neutrophils were highly activated. The aim of this study was to assess an inflammatory condition and neutrophil activation in ESKD patients undergoing continuous ambulatory peritoneal dialysis (CAPD). Thirteen CAPD patients without infection, both sexes, aged 2.5–24 years, and group of healthy subjects (C) were studied. For comparative purposes the conservatively treated (CT) group of ESKD patients was included. Neutrophil elastase in complex with α₁-proteinase inhibitor (NE-α₁PI; ELISA), α₁-proteinase inhibitor (α₁PI; radial immunodiffusion) and interleukin-8 (IL-8; ELISA) were measured in the blood samples from CAPD, CT, and C group and in the peritoneal dialysate fluid (PDF) samples of patients on CAPD. A significantly increased plasma NE-α₁PI levels (median 176.5 μg/L, range 85.2–373.2 μg/L; p < 0.00005), serum IL-8 (median 18.6 pg/mL, range 15.73–35.28 pg/mL; p < 0.05), and slightly decreased serum α₁PI (median 1,540 mg/L, range 1,270–1,955; p ≤ 0.05) compared to the control groups were found. There were no significant differences of analyzed parameters between CAPD and CT patients. The concentration ratio of NE-α₁PI, α₁PI and IL-8 in blood/PDF was 29.97, 8.24, and 4.48, respectively. There were significantly positive correlations between serum and PDF concentration of α₁PI and IL-8 (r = 0.613, p < 0.05; r = 0.59; p < 0.005, respectively). The results of our study demonstrate that neutrophils are highly activated in non-infected CAPD patients. The pivotal marker of this activation is NE-α₁PI. It may contribute to chronic inflammation and tissues injury.

Gene expression profiling of whole blood in ipilimumab-treated patients for identification of potential biomarkers of immune-related gastrointestinal adverse events

BACKGROUND

Treatment with ipilimumab, a fully human anti-CTLA-4 antibody approved for the treatment of advanced melanoma, is associated with some immune-related adverse events (irAEs) such as colitis (gastrointestinal irAE, or GI irAE) and skin rash, which are managed by treatment guidelines. Nevertheless, predictive biomarkers that can help identify patients more likely to develop these irAEs could enhance the management of these toxicities.

METHODS

To identify candidate predictive biomarkers associated with GI irAEs, gene expression profiling was performed on whole blood samples from 162 advanced melanoma patients at baseline, 3 and 11 weeks after the start of ipilimumab treatment in two phase II clinical trials (CA184004 and CA184007). Overall, 49 patients developed Grade 2 or higher (grade 2+) GI irAEs during the course of treatment. A repeated measures analysis of variance (ANOVA) was used to evaluate the differences in mean expression levels between the GI irAE and No-GI irAE groups of patients at the three time points.

RESULTS

In baseline samples, 27 probe sets showed differential mean expression (≥ 1.5 fold, P ≤ 0.05) between the GI irAE and No-GI irAE groups. Most of these probe sets belonged to three functional categories: immune system, cell cycle, and intracellular trafficking. Changes in gene expression over time were also characterized. In the GI irAE group, 58 and 247 probe sets had a ≥ 1.5 fold change in expression from baseline to 3 and 11 weeks after first ipilimumab dose, respectively. In particular, on-treatment expression increases of CD177 and CEACAM1, two neutrophil-activation markers, were closely associated with GI irAEs, suggesting a possible role of neutrophils in ipilimumab-associated GI irAEs. In addition, the expression of several immunoglobulin genes increased over time, with greater increases in patients with grade 2+ GI irAEs.

CONCLUSIONS

Gene expression profiling of peripheral blood, sampled before or early in the course of treatment with ipilimumab, resulted in the identification of a set of potential biomarkers that were associated with occurrence of GI irAEs. However, because of the low sensitivity of these biomarkers, they cannot be used alone to predict which patients will develop GI irAEs. Further investigation of these biomarkers in a larger patient cohort is warranted.

Elastase, α1-proteinase inhibitor, and interleukin-8 in pre-dialyzed and hemodialyzed patients with chronic kidney disease

BACKGROUND

Neutrophil elastase in complex with α(1) -proteinase inhibitor (NE-α(1) PI) and interleukin (IL)-8 may serve as indicators of neutrophil activation and inflammatory stage. The aim of the study was to evaluate NE-α(1) PI, α(1)-PI, and IL-8 levels in the blood of patients with chronic kidney disease (CKD) undergoing hemodialysis (HD) or conservatively treated (CT). The influence of a single HD session on the investigated parameters was also assessed.

METHODS

Blood samples were obtained from two groups of hemodialyzed patients (children/young adults [group HD1, n = 8] and adults [group HD2, n = 13]), as well as 13 CT patients and a group of healthy subjects. The proteins were measured using enzyme-linked immunosorbent assay or radial immunodiffusion.

RESULTS

There were no significant differences in NE-α(1) PI, α(1)-PI, and IL-8 concentrations between the HD1 and HD2 patients. The levels of NE-α(1) PI were considerably higher than normal in both groups of HD patients (before and after the HD session) and in the CT patients. Higher titers of NE-α(1) PI (P < 0.05) and α(1)-PI (P < 0.01) were obtained in the adults during the course of HD. Increased NE-α(1) PI was positively correlated with α(1)-PI. The serum concentration of IL-8 was significantly higher in the HD2 patients before and after dialysis than in the controls.

CONCLUSIONS

The data indicate that in CKD patients, neutrophils are highly activated both in the pre-dialyzed period and on regular HD. Contact with the dialysis membrane during HD causes a significant increase in blood NE-α(1) PI and α(1)-PI in adults, but not in children/young adults. NE-α(1) PI seems to be a much better indicator of an inflammatory state in CKD patients than free α(1)-PI or IL-8.

Diagnostic value of proinflammatory interleukins in parapneumonic effusions

Pleural effusion appears in approximately 40% of patients with pneumonia. Given that microbiology results are often negative, its diagnosis is frequently based on clinical criteria. Our study consisted of 266 patients, divided into infectious (n = 34), tuberculous (n = 54), paraneoplastic (n = 63), miscellaneous exudates (n = 53), and transudates (n = 62). Interleukin (IL)-6, IL-8, and IL-1beta were measured in the pleural fluid and serum of all patients, as well as the different cell populations in the pleural fluid. Analysis of the receiver operating characteristic curves of the different ILs in pleural fluid for the diagnosis of parapneumonic/empyematous effusion showed IL-6 with a sensitivity of 38.2% and specificity of 97.4%, IL-8 with a sensitivity of 73.5% and specificity of 65.1%, IL-1beta with a sensitivity of 55.6% and specificity of 91.3%, and total neutrophil count in pleural fluid (PNEU) with a sensitivity of 62.9% and specificity of 91.1%. The combination of IL-1beta and PNEU improved the yield, with a sensitivity of 75.7% and a specificity of 83.1%.

Differentiated expression of the lactate dehydrogenase subunit M in pleural fluids of neoplastic aetiology

OBJECTIVE

An anaerobic type of glycolysis exemplified by hyperproduction of the lactate dehydrogenase (LDH) subunit M has been detected in lung tumours, while a similar pattern has been found in concomitant pleural effusions (PE). The aim of this study was to verify the presence of the LDH subunit M in PEs of different aetiology and to compare its expression with markers of inflammation.

MATERIAL AND METHODS

LDH isoenzymes were estimated and the LDH5/LDH1 coefficient was calculated in paraneoplastic PEs (n = 99), including subgroups with a different tumour ultrastructure, origin and pleural involvement. The expression pattern was compared with parainflammatory PEs (n = 21), transudates (n = 16) and with the expression of 13 inflammatory markers in PEs.

RESULTS

The LDH5/LDH1 coefficient was higher in PEs associated with non-small-cell lung cancer (NSCLC) and with pleura-invading tumours, and lower in PEs of small-cell lung cancer and tumours without a confirmed pleural involvement. The LDH5/LDH1 coefficient positively correlated with uPA, IL-8, IL-10, sICAM, sVCAM, MPO and MMP-9.

CONCLUSIONS

In accordance with inflammatory markers, it appears that the expression of LDH and its isoenzymes in PEs reflects the host reaction in pleural space and, in NSCLC, may also feature the anaerobic phenotype of cancer cells.

Biomarkers of leukocyte traffic and activation in the vaginal mucosa

Development of novel vaginal spermicides and anti-human immunodeficiency virus (HIV) microbicides requires careful assessment of their potential to recruit and activate CD4+ HIV-1 host cells in the female genital tract mucosa, two events that facilitate HIV-1 infection. Leukocyte traffic and activation are mediated by proinflammatory cytokines and chemokines, e.g. interleukin (IL)-1, IL-6 and IL-8, which have been detected in vaginal secretions in association with epithelial damage and infections. These proinflammatory mediators, however, have bidirectional, destructive as well as beneficial, effects on the mucosal barrier, and may be counterbalanced by endogenous inhibitors. Here we propose additional biomarkers for the evaluation of compound-induced cervicovaginal mucosal inflammation. Displaying different temporal patterns of detection, the levels of soluble E-selectin, vascular adhesion molecule-1, CD14 and myeloperoxidase in vaginal secretions reflected the mucosal leukocyte reaction to proinflammatory compounds being evaluated for safety in an improved rabbit vaginal irritation model. These biomarkers, which were also detected in human vaginal secretions, may be used to enhance the characterization of mucosal safety of vaginally applied compounds, both in animal as well as clinical studies.

Inflammation and clinical repercussions of pleurodesis induced by intrapleural talc administration

Although reports on pleurodesis date back to the beginning of the 20th century, the search for the ideal sclerosing agent is ongoing. Several agents have been studied and used, but talc continues to be the most popular. However, potentially harmful systemic side effects have been associated with talc pleurodesis. In this article we discuss the likely mechanisms of pleural inflammation and pleurodesis with emphasis on the systemic response due to the instillation of talc into the pleural space.

Pleural injury and pleurisy-induced progelatinase B/proMMP-9 is associated with markers of neutrophil degranulation

OBJECTIVE

Progelatinase B/proMMP-9 has recently been identified as an indicator of pleural inflammation, presumably originating from granulocytes. The aim of this study was to verify the origin of progelatinase B by simultaneous estimation of specific markers of neutrophil recruitment and activation in pleural effusions following induced pleurisy and pleural injury.

MATERIAL AND METHODS

Sixty-three samples of pleural fluid from patients undergoing therapeutic talc pleurodesis (n = 8) and explorative thoracoscopy (n = 3) collected before and at different time intervals after the intervention were analyzed for progelatinase B and neutrophil gelatinase-associated lipocalin (NGAL)-gelatinase complex by substrate electrophoresis, for myeloperoxidase (MPO) and interleukin-8 (IL-8) by immunoadsorbent sandwich assay, as well as for leukocyte count, C-reactive protein (CRP) and total protein (TP).

RESULTS

A significant increase in free and NGAL-complexed progelatinase B, MPO and IL-8 was recorded within 48 h following treatment in all subjects. Progelatinase B was strongly correlated with NGAL-gelatinase complex (r = 0.88, p = 0.001), MPO (r = 0.81, p = 0.001), neutrophil count (r = 0.75, p = 0.01) and IL-8 (r = 0.71, p = 0.001), but not with CRP and TP.

CONCLUSIONS

The results support the neutrophil origin of the proenzyme, which confirms progelatinase B as an indicator of a local inflammatory reaction. Quantifying the inflammatory reaction may be helpful in the evaluation of both the technical variants of therapeutic pleurodesis and finer discrimination of paraneoplastic effusions.

Correlation between interleukin-10 and in situ necrosis and fibrosis suggests a role for interleukin-10 in the resolution of the granulomatous response of tuberculous pleurisy patients

In order to identify mediators involved in immune-mediated disease regression, the pleural cytokine and histopathological profile was evaluated in tuberculous pleurisy patients with varied disease duration and clinical presentation, previous to chemotherapy. Interleukin (IL)-10, interferon (IFN)-gamma and tumor necrosis factor (TNF) levels in pleural fluids were shown to decrease with disease time. IL-10 was positively correlated with IFN-gamma, TNF and necrosis area in pleural sections. To parallel these findings with disease regression, individuals showing fever, anorexia, and progressive exudate in the pleural cavity (active disease) were compared with patients without symptoms and with a decrease in exudate volume (regressive disease). IFN-gamma and TNF levels were lower in regressive disease, as well as reduced necrosis area in pleural sections. Our results indicate that tissue destruction and a prominent Th1 response mark the early phase of tuberculous pleurisy and suggest that down-modulation of this response, with the possible participation of IL-10, is associated with disease resolution.

The differential diagnostic values of cytokine levels in pleural effusions

The aim is to examine whether the changes in pleural fluid interleukin (IL)-1beta, IL-2, IL-6, and IL-8 levels were significant in differential diagnosis of childhood pleural effusions. IL-1beta, IL-2, IL-6, and IL-8 levels in pleural fluids of all 36 patients were measured. The levels of IL-1beta, IL-2, IL-6, and IL-8 in pleural fluids were statistically significantly higher in the transudate group compared with those of the exudate group. The levels of IL-1 beta, IL-6, and IL-8 were also found to be statistically significantly higher in the empyema group compared with both the parapneumonic and the tuberculous pleural effusion groups. The levels of IL-2 and IL-6 were detected to be statistically significantly higher in the tuberculous pleural effusion group in comparison with those of the parapneumonic effusion group. The results showed that pleural fluids IL-1beta, IL-2, IL-6, and IL-8 could be used in pleural fluids exudate and transudate distinction.

Interleukin-8, monocyte chemoattractant protein-1 and IL-10 in the vitreous fluid of patients with proliferative diabetic retinopathy

AIMS

To determine the intra-vitreous levels of two pro-inflammatory cytokines [interleukin-8 (IL-8), monocyte chemoattractant protein-1 (MCP-1)] and the anti-inflammatory cytokine interleukin-10 (IL-10) in patients with proliferative diabetic retinopathy (PDR). In addition, the relationship between the profile of cytokines and PDR activity has also been evaluated.

PATIENTS AND METHODS

The study included 22 consecutive diabetic patients with PDR (4 Type 1 and 18 Type 2) on whom a vitrectomy was performed. Sixteen age-matched non-diabetic patients with other conditions requiring vitrectomy, but in which the retina was not directly affected by neovascularization served as a control group. IL-8, MCP-1 and IL-10 were measured by enzyme-linked immunosorbent assay (ELISA).

RESULTS

The vitreal levels of both IL-8 and MCP-1 were strikingly higher in diabetic patients with PDR in comparison with the control group [173.5 (64-1670) vs. 49 pg/ml (25-145), P < 0.001, and 2171 (388-6155) vs. 438 pg/ml (207-1344), P < 0.001, respectively]. In addition, the vitreous concentrations of IL-8 and MCP-1 were higher in patients with active PDR than in those patients with quiescent PDR [324.5 (80-1670) vs. 173.5 pg/ml (64-487), P = 0.06 and 3596 (1670-6155) vs. 1143 pg/ml (388-2500), P = 0.01, respectively]. However, vitreal levels of IL-10 in diabetic patients were similar to that obtained in the control group [2.89 (1.55-5.50) vs. 2.46 pg/ml (2.2-5.41), P = NS].

CONCLUSIONS

The pro-inflammatory cytokines IL-8 and MCP-1 are increased in the vitreous fluid of PDR patients without an increase in the anti-inflammatory cytokine IL-10. In addition, both IL-8 and MCP-1 intra-vitreous levels correlated with PDR activity, thus suggesting that these cytokines may be pathogenically important in PDR.

Useful clinical biological markers in diagnosis of pleural effusions in children

In a patient with an undiagnosed pleural effusion, the first question to answer is whether the fluid is an exudate or a transudate. This is usually determined by means of Light's criteria, which differentiate transudative effusions from exudative effusions by measuring the levels of total protein and lactate dehydrogenase in the pleural fluid (PF) and serum. In patients under diuretic treatment, Light's criteria misclassify transudates as exudates, but the serum to pleural fluid albumin gradient usually remains above 12 g/L. When tests are done only in PF, protein concentration >30 g/L performs at least as well as the other individual markers. To diagnose tuberculous pleuritis among exudates, PF adenosine deaminase and PF interferon-g exhibit high diagnostic accuracy. When malignancy is suspected the addition of tumour markers to the results of cytologic analysis increases the rate of detection. Other biochemical markers are useful in specific circumstances involving pleural effusion, such as amylase in effusions due to pancreatitis, or oesophageal rupture, and triglycerides in chylothorax. Several PF markers are associated with complicated parapneumonic effusion - e.g. low PF pH and glucose, and high PF LDH activity -- although PF pH appears to be the best biochemical aid in decisions regarding chest tube drainage. Recent reports suggest that neutrophil-derived enzymes (polymorphonuclear elastase and myeloperoxidase) can be useful as early indicators of the need of chest tube insertion; however these findings must be confirmed in large series. This review discusses the clinical usefulness of biochemical markers in the diagnosis and management of pleural effusions. The vast majority of prospective studies in this field have been conducted in adults and, although the mechanisms of pleural effusion production do not differ in children and adults, the prevalence of each etiologic cause does. Therefore it seems advisable to confirm or recalculate the predictive values of each marker in the paediatric population.

Implication of cord blood myeloperoxidase but not of soluble p-selectin levels in preterm deliveries

Although maternal amniotic and vaginocervical cytokines are known to play a role in triggering preterm delivery, the effects of activating fetal phagocytes and platelets are not clear. In an attempt to clarify this issue, we measured levels of myeloperoxidase (MPO), a phagocyte activation marker, and soluble p-selectin (sCD62p), a platelet activation marker, in umbilical cord blood samples from 2200 consecutive cord blood collections, 106 of which were from preterm infants. MPO and sCD62p levels were correlated to gestational age and preterm delivery. It was found that MPO levels were significantly higher in preterm infants and were not significantly correlated to gestational age. In contrast, sCD62p levels were lower in preterm infants and were negatively correlated to gestational age. In summary, we showed that fetal phagocyte activation as demonstrated by higher cord blood MPO levels is associated with preterm delivery, but platelet activation as shown by lower sCD62p levels is not. This suggests that fetal phagocyte activation may be implicated in preterm delivery, and subsequently in prematurity-related inflammatory insults.

LTB4 is present in exudative pleural effusions and contributes actively to neutrophil recruitment in the inflamed pleural space

The pleural space is a virtual compartment between the lung and chest wall that becomes filled with fluid and inflammatory cells during a variety of respiratory diseases. Here, we study the potential role of the eicosanoid metabolite leukotriene B4 (LTB4) in disparate diseases leading to acute (pneumonia) or chronic (tuberculosis, cancer) inflammation of the pleural space. LTB4 concentrations were significantly higher in pleural fluid due to pneumonia, tuberculosis and cancer with respect to congestive heart failure and correlated with neutrophil elastase, which is used as an indication of state of activation of neutrophils in the pleural space. Moreover, pleural LTB4 was biologically active, as an anti-LTB4 antibody partially neutralized the chemotactic activity of parapneumonic, tuberculous and cancer effusions. Macrophages, neutrophils, lymphocytes, mesothelial cells and cancer cells all expressed mRNA for 5-lipoxygenase, the enzyme that initiates leukotriene synthesis leading to the production of LTB4, in exudative pleural effusions. Upon stimulation in transudative pleural effusions, pleural macrophages produced, in a time-dependent fashion, a significantly higher concentration of LTB4 than mesothelial cells. These studies demonstrate that different cell types are capable of producing LTB4 in the inflamed pleural space and that this mediator may play a crucial role in the recruitment of neutrophils into the pleural space.

Accuracy of chest sonography and polymorphonuclear elastase in the assessment of bacterial pleural effusion

Background: The relationship between chest sonography findings and inflammatory markers for assessing bacterial pleural effusion is not well established. We decided to study the accuracy of chest sonography in determining the nature of bacterial pleural effusion and its relationship with polymorphonuclear elastase (PMN-E) results. Methods: Pleural sonography and PMN-E were evaluated in a prospective study of 144 consecutive patients with pleural effusion of various etiologies: 25 complicated parapneumonic, 18 uncomplicated parapneumonic, 33 tuberculous, 17 malignant, 12 transudates, and 39 of unknown etiology. The sonographer distinguished between anechoic and septated pattern. The relationship between sonographic appearance and inflammatory markers was evaluated. Results: All of the complicated parapneumonic, 11 uncomplicated parapneumonic, and 28 tuberculous effusions were septated. Septated pattern and PMN-E value were independent predictors of infectious pleural disease (p <0.05). The simultaneous presence of a septated pattern and a PMN-E higher than 100 microg/l had a sensitivity of 79.1% and a specificity of 91.1% for the diagnosis of bacterial effusions. Conclusions: PMN-E level and the sonographic pattern of pleural fluid may be useful in the diagnosis of bacterial pleural effusions.

Cytokines in pleural liquid for diagnosis of tuberculous pleurisy

An elevated level of adenosine deaminase (ADA) in pleural liquid has been considered as a supplemental diagnostic marker for tuberculous pleurisy. However, this is complicated by false-positives and -negatives. Recently, it has been revealed that various cytokines are intimately involved in the pathognomonic physiology of tuberculosis. In this study, interleukin-8 (IL-8), tumour necrosis factor alpha (TNFalpha) and interferon gamma (IFNgamma) were compared with ADA in pleural liquid of patients with inflammatory (21 cases), malignant (28 cases) and tuberculous (21 cases) disease. The pleural ADA, IL-8, TNFalpha and IFNgamma levels in the tuberculous group were higher than in the other three groups. Analysis of receiver operating characteristic (ROC) curves, to evaluate the utility of the various parameters, demonstrates values for the area under the curve (AUC) of 0.770, 0.875, 0.892 and 0.987, respectively for IL-8, TNFalpha, ADA and IFNgamma. No false-positives were encountered with IFNgamma and only one case with a small volume of pleural liquid was a false-negative. This indicates that IFNgamma is a very reliable marker of tuberculous pleurisy.

[Residual pleural thickening in tuberculous pleuritis. Associated factors]]

BACKGROUND

To study the factors related to the development of residual pleural thickening in pleural tuberculosis.

PATIENTS AND METHODS

We studied 39 patients with tuberculous pleural effusion. A chest X-ray was taken of each patient at the end of treatment. The patients' medical histories, pleural fluid findings and diagnostic chest films were evaluated. Residual pleural thickening was defined as thickening that was visibly greater than 2 mm in the lower side portion of the chest film.

RESULTS

Residual pleural thickening developed in 26% of patients and was found mainly in men (RR = 3.86). In no patients with Löwenstein-Jensen cultures positive for Mycobacterium tuberculosis did pleural complications develop.

CONCLUSION

Residual pleural thickening is a common complication of tuberculous pleural effusion. Residual pleural thickening in tuberculous pleurisy occurs more often in men and older patients, and in cases in which pleural liquid culture is negative for M. tuberculosis.

Plasma cytokines: what we are measuring

Immunoassays, in particular enzyme-linked immunosorbent assays, have become increasingly important tools for the measurement of plasma cytokines. However, many technical factors contribute to the complexity of their quantitation. The study of plasma cytokine levels is also of limited value, and complementary methods are now available to investigate and understand more precisely the involvement of cytokines in pathological processes.