Neutrophil chemokines in cultured nasal fibroblasts

IL-8 and IFN-γ as Preoperative Predictors of the Outcome of Tonsillectomy

OBJECTIVES

Tonsillectomy (TE) and tonsillotomy (TO) due to recurrent episodes of acute tonsillitis (RAT) belong to the most frequent surgical procedures. However, an adequate objective marker predicting the outcome of TE/TO preoperatively is missing.

METHODS

Patients with RAT who underwent TE/TO (n = 31) were included in this pilot study. A panel of cytokines and chemokines in serum and saliva were determined preoperatively. Health-related quality of life was assessed pre- and postoperatively by the Tonsillectomy Outcome Inventory-14.

RESULTS

Health-related quality of life improved significantly after surgery. Increased serum levels of interleukin-8 (IL-8) and interferon gamma (IFN-γ) are associated with a less successful outcome. No correlation between the number of acute tonsillitis episodes and the health-related quality of life after TE or TO could be observed.

CONCLUSIONS

Tonsillectomy and TO improve health-related quality of life independently from the number of past acute tonsillitis episodes. Interleukin-8 and IFN-γ in serum may serve as promising markers, predicting the benefit of TE or TO for patients preoperatively.

Inula helenium and Grindelia squarrosa as a source of compounds with anti-inflammatory activity in human neutrophils and cultured human respiratory epithelium

ETHNOPHARMACOLOGICAL RELEVANCE

During the epidemic season, over 90% of acute wheezing disease is associated with bronchial inflammation. Both neutrophil- and eosinophil-mediated inflammation have been involved in the pathophysiology of acute bronchitis, but neutrophil cell recruitment has been shown to be dominant. The ongoing inflammation increases the chemotaxis of neutrophils to inflamed site providing to their overaccumulation. The pharmacological reduction of neutrophil migration can be limited by suppression of major chemo-attractants and cytokines (IL-8, IL-1β and TNF-α) release and downregulation of adhesive molecules.

AIM OF THE STUDY

During a screening of plants traditionally used in respiratory tracts diseases (e.g. cough, rhinitis, bronchitis, throat infection, fever, influenza) in Europe, we have selected roots of Inula helenium and aerial parts of Grindelia squarrosa as a potential source of compounds limiting neutrophil migration.

MATERIALS AND METHODS

The effect on IL-8, IL-1β and TNF-α release by neutrophils and respiratory epithelium cell line (A549) was measured by enzyme-linked immunosorbent assay (ELISA). The surface expression of adhesive molecules was analyzed with flow cytometry, and the neutrophil attachment to the epithelial cells was assessed fluorimetrically.

RESULTS

We confirmed the ability of selected extracts and compounds to suppress neutrophil binding to the epithelium surface via downregulation of β2 integrin. Alantolactone and grindelic acid have shown significant suppression of IL-8, TNF-α and IL-1β release comparable with budesonide, used as a positive control.

CONCLUSIONS

The present study demonstrated that Inula helenium and Grindelia squarrosa, which have been traditionally used in Europe as medicinal plants, are a valuable source of active compounds with anti-inflammatory activity. Our observations justify the traditional use of I. helenium and G. squarrosa for a treatment of inflammation-based diseases in respiratory tract.

Predictive markers of long-term recurrence in chronic rhinosinusitis with nasal polyps

BACKGROUND

In last years, many attempts were made to recognize chronic rhinosinusitis with nasal polyps (CRSwNP) phenotypes focusing on identifying relevant key pathogenic molecules. Polyps recurrence rate ranges from 4% to 60%, so it's clear that not all clinical and immunologic factors associated with recurrence are known.

OBJECTIVE

We investigate the inflammatory profile in patients with long term recurrent and non-recurrent CRSwNPs and if a specific profile is associated with recurrence, comparing eosinophilic, neutrophilic and lymphocytic infiltration, as well as IL-5 and IL-8 expression to long term recurrence rate.

METHODS

This prospective study included 44 adult patients with CRSwNP treated with endoscopic sinus surgery between 2008 and 2010. Long term follow-up data (8-10 years) indicated that among 44 patients, 18 (40.1%) experienced long term recurrence of nasal polyposis needing maximal medical treatment or revision surgery. We realized two groups: one with patients who didn't present long term recurrence (26 patients) and another with patients who presented long term recurrence (18 patients) and in both groups eosinophilic, neutrophilic and lymphocytic infiltration and IL-5 and IL-8 expression were measured.

RESULTS

The parameters that reached statistical significance (p < 0.05) comparing the two groups were eosinophilic infiltration and IL-5 expression, whereas neutrophilic and lymphocytic infiltration, as IL-8 expression didn't show any significant difference. Asthma and aspirin intolerance seemed significantly more frequent in patients with recurrence, while allergy presented not statistically significant difference between two groups.

CONCLUSIONS

We can conclude that high eosinophilic infiltration and high IL-5 expression in CRSwNP correlate with higher rate of long term recurrence, while neutrophilic and lymphocytic infiltration, and IL-8 expression don't correlate with it. These findings provide the opportunity to improve our ability to predict the prognosis of surgical intervention, although it is still needed to explore the optimal predictor of outcome in CRSwNP.

The Role of the Fibroblast in Inflammatory Upper Airway Conditions

Upper airway inflammation is one of the most frequent health care presentations. This is perhaps not surprising with our exposure to a myriad of environmental microbes, pollutants, and allergens. The precise pathophysiological mechanisms that cause persistent, exaggerated, upper airway inflammation rather than acute resolving illness remain unclear. Analysis of upper airway specimens identifies specific inflammatory cells, cytokine signatures, and fibrotic airway remodeling. Recent research has highlighted the role of stromal cells in the generation and persistence of chronic inflammation. Rather than simply being scaffolding or extracellular matrix-secreting cells on which organ systems are built, stromal cells including fibroblasts and osteocytes have their own independent immunologic functions. Here, we review the emerging inflammatory roles of upper airway fibroblasts, the majority of which appear to influence immune cell chemotaxis and amplify the inflammatory response.

Effects of IL-17 on expression of GRO-α and IL-8 in fibroblasts from nasal polyps

Recent studies indicated that interleukin (IL)-17, growth-related oncogene (GRO)-α and IL-8 play an important role in the pathogenesis of nasal polyps. However, the effects of the increased amount of IL-17 and the production of GRO-α and IL-8 in human nasal polyp fibroblasts are not completely understood. This study aimed to determine the effects of the increased IL-17 on the changes of GRO-α and IL-8 expression in human nasal polyp fibroblasts and further investigate the mechanism of neutrophil infiltration in nasal polyps. Nasal polyp fibroblasts were isolated from six cases of human nasal polyps, and the cells were stimulated with five different concentrations of IL-17. Real-time fluorescence quantitative polymerase chain reaction (RT-PCR) was used to detect the mRNA expression of GRO-α and IL-8. The mRNA of GRO-α and IL-8 was expressed in unstimulated controls and remarkably increased by stimulation with IL-17. Moreover, the levels of GRO-α and IL-8 produced by fibroblasts were increased gradually with the increases in IL-17 concentrations. The present study showed that nasal fibroblasts can produce GRO-α and IL-8, and their production is remarkably enhanced by IL-17 stimulation, thereby clarifying the mechanism of the IL-17 mediated neutrophil infiltration in nasal polyps. These findings might provide a rationale for using IL-17 inhibitors as a treatment for nasal inflammatory diseases such as nasal polyps.

Inhibition of IL-8 production by green tea polyphenols in human nasal fibroblasts and A549 epithelial cells

The attraction of leukocytes to tissues is essential in order for inflammation and the host response to infection to occur. Airway inflammation is a very common cause illness with a substantial impact on health care. Neutrophils play an essential role in the host defense and in inflammation, but the latter may trigger and sustain the pathogenesis of a range of acute and chronic diseases. Infiltration of neutrophils occurs as a response to chemoattractant molecules by resident tissue cells. The recruitment of neutrophils in airway inflammation may account for the generation of IL-8. To evaluate the effectiveness of green tea polyphenols in the modulation of airway inflammation through the blocking of neutrophil chemokine production, nasal mucosal fibroblasts and A549 bronchial epithelial cells were analyzed for the production of IL-8. Both nasal mucosal fibroblasts and bronchial epithelial cells produced significant amounts of IL-8 through stimulation of IL-1beta. Tea polyphenols were very effective in the inhibition of IL-8 production. Among the polyphenols tested, EGCG and ECG showed strong inhibitory activity in dose-dependent manners. EGC and EC showed moderate inhibition at 48 h culture, whereas (-)catechin was not effective. Production of IL-8 after stimulation by proinflammatory cytokines in both nasal fibroblasts and bronchial epithelial cells was significantly blocked by pretreatment with green tea polyphenols.

Granulocyte chemotactic protein 2 (gcp-2/cxcl6) complements interleukin-8 in periodontal disease

BACKGROUND AND OBJECTIVE

Mucosal inflammatory responses are orchestrated largely by pro-inflammatory chemokines. The chemokine granulocyte chemotactic protein 2 (CXCL6) is involved in neutrophil recruitment and migration. Previous studies have shown that granulocyte chemotactic protein 2 is up-regulated during mucosal inflammation (e.g. in inflammatory bowel disease), similarly to the functionally and structurally related chemokine interleukin-8. Nevertheless, unlike interleukin-8, a role of granulocyte chemotactic protein 2 in gingival inflammation has not been yet demonstrated. In this study we aimed to evaluate the expression of the chemokine granulocyte chemotactic protein 2 in clinically healthy vs. diseased gingival tissues and to explore possible correlations with clinical and microbiological markers of periodontitis.

MATERIAL AND METHODS

Gene expression in 184 'diseased' and 63 'healthy' gingival tissue specimens from 90 patients with periodontitis was analyzed using Affymetrix U133Plus2.0 arrays. The expression of granulocyte chemotactic protein 2 was further confirmed by real-time reverse transcription-polymerase chain reaction, western blotting and enzyme-linked immunosorbent assay, while the localization of granulocyte chemotactic protein 2 in gingival tissues was analyzed by immunohistochemistry. Plaque samples from the adjacent periodontal pockets were collected and evaluated for 11 species of periodontal bacteria using checkerboard DNA-DNA hybridizations.

RESULTS

Among all known chemokines, GCP-2 expression was the most up-regulated (3.8-fold, p < 1.1 x 10(-16)), in 'diseased' vs. 'healthy' tissue as compared to a 2.6-fold increased expression of interleukin-8 mRNA (p < 1.2 x 10(-15)). Increased expression of granulocyte chemotactic protein 2 correlated with higher levels of 'red' and 'orange' complex pathogens and with increased probing depth, but not with attachment loss. Immunohistochemistry showed that granulocyte chemotactic protein 2 was expressed in gingival vascular endothelium.

CONCLUSION

The level of expression of granulocyte chemotactic protein 2 correlates with the severity of periodontitis and appears to act as a hitherto unrecognized functional adjunct to interleukin-8 in diseased gingival tissues.

Tissue remodelling in upper airways: where is the link with lower airway remodelling?

Tissue remodelling reported in upper airways include epithelial hyperplasia, increased matrix deposition in the nasal or paranasal lining, matrix degradation and accumulation of plasma proteins. Genetic influences, foetal exposures and early life events may contribute to structural changes such as subepithelial fibrosis from an early age. Other structural alterations are related to duration of the disease and long-term uncontrolled inflammation. Structural changes may increase alteration of the protective functions of the upper airways namely by affecting mucociliary clearance and conditioning of inspired air. The sequences of tissue changes during wound repair of upper airway mucosa after surgery are illustrative of the complexicity of tissue modelling and remodelling and could be considered as an important source of information for a better understanding of the complex relationship between inflammatory reaction, of the subsequent tissue damages and fibroblast metabolism of upper airways.

Primary role of growth-related oncogene-alpha and granulocyte chemotactic protein-2 as neutrophil chemoattractants in chronic rhinosinusitis

BACKGROUND

The aetiology of chronic rhinosinusitis (CRS) remains unclear. The purpose of this study was to investigate neutrophil-attracting chemokine patterns in CRS without nasal polyposis.

METHODS

The biological activity of the chemokines was identified using a two-step high-performance liquid chromatography (HPLC) technique combined with a bioassay in extracts from 55 CRS patients, and in the turbinate mucosa (TM) of patients (N=51) undergoing septumplasty. The biologic activity of each chemokine was assessed using blocking antibodies to chemokines. Immunolocalization of detected neutrophil chemokines was performed by quantitative evaluation of immunohistochemistry. Besides, PCR analysis was performed to quantify neutrophil chemokine mRNA.

RESULTS

In CRS, the chemokines primarily detected by two-step HPLC were growth-related oncogene-alpha (GRO-alpha) and the granulocyte chemotactic protein-2 (GCP-2). Blocking of GCP-2 and GRO-alphad each resulted in chemotaxis inhibition rates of 43.3% and 35.9%, respectively, whereas anti-IL-8 and anti-ENA-78 had no effect. Both GCP-2 and GRO-alphad were generally synthesized by the surface epithelium and mucosal glands while GRO-alpha in particular was synthesized by endothelial cells, as shown by immunohistochemistry. The concentrations of the chemokines IL-8 and epithelial cell-derived neutrophil attractant-78 (ENA-78) were low in CRS and TM.

CONCLUSION

It appears that both GRO-alpha and GCP-2 contribute to neutrophil chemotaxis in CRS, whereas IL-8 and ENA-78 appear to be of secondary importance for the chemotaxis of neutrophils in this condition. The expression of chemokines in mucosal gland cells is the main phenomenon involved in constitutive neutrophil chemotaxis in the TM.

Neutrophil chemokines in epithelial inflammatory processes of human tonsils

CXC chemokines are thought to play an important role at sites of inflammation. Because ELR(+) CXC chemokines are expressed in different types of tonsillitis we investigated the role of the surface/crypt epithelium of human tonsils in producing ELR(+) CXC chemokines: interleukin (IL)-8 (CXCL8), ENA-78 (CXCL5), GRO-alpha (CXCL1) and GCP-2 (CXCL6). Tonsillar tissue was obtained from patients undergoing tonsillectomy and chemokine expression was investigated by means of immunohistochemistry. A549 cells were used as a model to study kinetics of chemokine expression in epithelial cells. Cells were stimulated with tumour necrosis factor (TNF)-alpha, lipopolysaccharide (LPS) and supernatants derived from aerobic/anaerobic Staphylococcus aureus strains. Chemokine expression was measured by quantitative reverse transcription-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA). We observed epithelial expression of IL-8, GRO-alpha and GCP-2 in different types of tonsillitis, whereas ENA-78 was rarely expressed. In A549 cells abundant expression of ENA-78 was detected. IL-8 and GCP-2 are expressed in an acute type of tonsillitis whereas GRO-alpha was frequently detectable both in chronically and acutely inflamed tonsils. ENA-78 does not seem to play a pivotal role in tonsillitis in vivo.

Biologically active neutrophil chemokine pattern in tonsillitis

To gain an insight into the mechanisms of chronic and acute inflammation, the production of neutrophil chemokines in different types of tonsillitis - hyperplastic tonsillitis (HT), recurrent tonsillitis (RT) and peritonsillar abscesses (PA) - was investigated. The chemokines interleukin-8 (IL-8), growth-related oncogene-alpha (GRO-alpha), epithelial cell-derived neutrophil attractant-78 (ENA-78) and granulocyte chemotactic protein-2 (GCP-2) were detected and shown to have different biological activities. With respect to the biological properties of CXC chemokines, the biological activity of the chemokines was identified using a three-step high-performance liquid chromatography (HPLC) technique, a bioassay involving measurement of neutrophil chemotaxis in a single Boyden chamber in tissue of HT, RT and PA. Using reverse transcription-polymerase chain reaction (RT-PCR), the chemokine concentrations were determined in the different tonsillitis entities. The chemokine pattern was dominated in PA by IL-8 and GRO-alpha and in RT by GRO-alpha. Hyperplastic tonsils of patients without a history of infection generated about five times lower IL-8 than PA. A protein concentration of GCP-2 was induced in PA and RT, whereas ENA-78 remained the same in all entities. In conclusion, it would appear that IL-8 was up-regulated in acute inflammation, whereas GRO-alpha dominated in chronic inflammation. ENA-78 seems not to play a pivotal role in inflammatory processes in tonsils. GCP-2 may serve as a substitute chemokine in certain inflammatory conditions as its quantity of mRNA and protein was higher in RT and PA than in HT.

The primary role in biologic activity of the neutrophil chemokines IL-8 and GRO-alpha in cultured nasal epithelial cells

Primary nasal epithelial cells were investigated for their ability to synthesize and deliver neutrophil chemotactic factors (chemokines) following tumor necrosis factor-alpha (TNF-alpha) induction. The chemokines interleukin8 (IL-8), growth-related oncogene-alpha (GRO-alpha), epithelial cell-derived neutrophil attractant-78 (ENA-78), and granulocyte chemotactic protein-2 (GCP-2) have been detected and characterized and shown to have different potencies in the chemotaxis of neutrophils. Cultures of primary nasal epithelial cells were treated with TNF-alpha in concentrations of 20 and 200 ng/ml for 2, 8, 24, and 72 h. The chemokine protein concentrations in the supernatants of the incubations were determined by the ELISA technique. Chemokine mRNA expression in epithelial cells was also measured using the reverse transcriptase-polymerase chain reaction (RT-PCR). The biologic activity of the chemokines was identified using a three-step high-performance liquid chromatography (HPLC) technique, a bioassay involving measurement of neutrophil chemotaxis in a single Boyden chamber. Both the IL-8 and GRO-alpha proteins and their respective mRNA appear to be induced by TNF-alpha in epithelial cells. The chemotactic responsiveness of both GRO-alpha and IL-8 appears to predominate after 24 h incubation with TNF-alpha. The chemokines GCP-2 and ENA-78 were only weakly induced by TNF-alpha. The neutrophil chemokines IL-8 and GRO-alpha were synthesized in nasal epithelial cell culture induced by TNF-alpha in biologically active concentrations of 0.8 ng/ml and 1.42 ng/ml, respectively. It appears that both the IL-8 and GRO-alpha chemokines may contribute to neutrophil tissue migration in sinusitis, whereas GCP-2 and ENA-78 are of secondary importance to the chemotaxis of neutrophils in this condition.