Chemokines in seasonal allergic rhinitis

Allergic rhinitis is associated with thromboembolic disease in pregnancy

Finding the risk factors for thromboembolic (TE) disease and preventing its development in pregnant women is important. Allergic rhinitis (AR) is a common chronic disease. We aim to find if AR is a risk factor. From 2004 to 2011, 55,057 pregnant women were recruited from a Taiwan database. They were grouped into AR and non-AR groups. The rate of TE and venous complications during pregnancy and 60 days after childbirth were compared between non-AR and the AR group. Those with AR diagnosed both before and after childbirth, meaning AR was not changed during pregnancy, the rates of TE (OR 2.64) and venous complications (OR 1.35) were higher compared to non-AR subjects. In those who underwent cesarean delivery, the rate was also higher in group 3 (OR 4.14). Those with AR before childbirth, without after, meaning AR was well controlled during pregnancy, the rate of TE was not higher than that of the non-AR subjects. Pregnant women with AR have an increased rate of TE. An increased rate of venous complications in these subjects might explain the increase in TE. If AR is well controlled during pregnancy, the rate of TE does not appear to increase.

Outdoor pollen-related changes in lung function and markers of airway inflammation: A systematic review and meta-analysis

BACKGROUND

Experimental challenge studies have shown that pollen can have early and delayed effects on the lungs and airways. Here, we qualitatively and quantitatively synthesize the evidence of outdoor pollen exposure on various lung function and airway inflammation markers in community-based studies.

METHODS

Four online databases were searched: Medline, Web of Science, CINAHL and Google Scholar. The search strategy included terms relating to both exposure and outcomes. Inclusion criteria were human-based studies published in English that were representative of the community. Additionally, we only considered cross-sectional or short-term longitudinal studies which investigated pollen exposure by levels or season. Study quality assessment was performed using the Newcastle-Ottawa scale. Meta-analysis was conducted using random-effects models.

RESULTS

We included 27 of 6551 studies identified from the search. Qualitative synthesis indicated associations between pollen exposure and predominantly type-2 inflammation in both the upper and lower airways, but little evidence for lung function changes. People with ever asthma and/or seasonal allergic rhinitis (SAR) were at higher risk of such airway inflammation. Meta-analysis confirmed a positive relationship between pollen season, eosinophilia and eosinophil cationic protein (ECP) in people with ever SAR but the results between studies were highly variable. Heterogeneity was reduced after further subgrouping by age, and the forest plots indicated that eosinophilic airway inflammation to outdoor pollen exposure increased with age.

CONCLUSION

Among people with ever asthma and ever SAR, exposure to increased ambient pollen triggers type-2 upper and lower airway inflammation rather than a non-specific or innate inflammation. These findings can lead to the formulation of specific pollen immunotherapy for susceptible individuals. Future research should be directed towards investigating lagged associations and effect modifications using larger and more generalized populations.

SYSTEMATIC REVIEW REGISTRATION

CRD42020146981 (PROSPERO).

Antiviral effects of statins

Introducing statins as possible widely-available drugs for the treatment of viral infections requires an in depth review of their antiviral properties. Despite some inconsistency, a large body of literature data from experimental and clinical studies suggest that statins may have a role in the treatment of viral infections due to their immunomodulatory properties as well as their ability to inhibit viral replication. In the present review, the role that statins may play while interacting with the immune system during viral infections and the possible inhibitory effects of statins on different stages of virus cell cycle (i.e., from fusion with host cell membranes to extracellular release) and subsequent virus transmission are described. Specifically, cholesterol-dependent and cholesterol-independent mechanisms of the antiviral effects of statins are reported.

Allergy Enhances Neurogenesis and Modulates Microglial Activation in the Hippocampus

Allergies and their characteristic T_H2-polarized inflammatory reactions affect a substantial part of the population. Since there is increasing evidence that the immune system modulates plasticity and function of the central nervous system (CNS), we investigated the effects of allergic lung inflammation on the hippocampus—a region of cellular plasticity in the adult brain. The focus of the present study was on microglia, the resident immune cells of the CNS, and on hippocampal neurogenesis, i.e., the generation of new neurons. C57BL/6 mice were sensitized with a clinically relevant allergen derived from timothy grass pollen (Phl p 5). As expected, allergic sensitization induced high serum levels of allergen-specific immunoglobulins (IgG1 and IgE) and of T_H2 cytokines (IL-5 and IL-13). Surprisingly, fewer Iba1⁺ microglia were found in the granular layer (GL) and subgranular zone (SGZ) of the hippocampal dentate gyrus and also the number of Iba1⁺MHCII⁺ cells was lower, indicating a reduced microglial surveillance and activation in the hippocampus of allergic mice. Neurogenesis was analyzed by labeling of proliferating cells with bromodeoxyuridine (BrdU) and determining their fate 4 weeks later, and by quantitative analysis of young immature neurons, i.e., cells expressing doublecortin (DCX). The number of DCX⁺ cells was clearly increased in the allergy animals. Moreover, there were more BrdU⁺ cells present in the hippocampus of allergic mice, and these newly born cells had differentiated into neurons as indicated by a higher number of BrdU⁺NeuN⁺ cells. In summary, allergy led to a reduced microglia presence and activity and to an elevated level of neurogenesis in the hippocampus. This effect was apparently specific to the hippocampus, as we did not observe these alterations in the subventricular zone (SVZ)/olfactory bulb (OB) system, also a region of high cellular plasticity and adult neurogenesis.

Ragweed-allergic subjects have decreased serum levels of chemokines CCL2, CCL3, CCL4 and CCL5 out of the pollen season

CC-chemokines are important mediators of the allergic responses and regulate the cell trafficking. The aim of this study was to examine the serum levels of CCL2/MCP-1, CCL3/MIP-1α, CCL4/MIP-1β and CCL5/RANTES, and to determine whether there are differences between ragweed-allergic subjects and healthy individuals out of the pollen season. Peripheral blood samples were collected from 24 subjects allergic to ragweed pollen and 12 healthy controls. Serum concentrations of chemokines/cytokines were measured by an enzyme-linked immunosorbent assay. We observed significantly decreased concentrations of CCL2/MCP-1, CCL3/MIP-1α, CCL4/MIP-1β and CCL5/RANTES in the sera of ragweed-allergic patients compared to the healthy individuals (32.2 vs. 106.4 pg/ml, 89.5 vs. 135.7 pg/ml, 63.4 vs. 119.2 pg/ml and 11.2 vs. 18.1 ng/ml, respectively, p < 0.01). In contrast to the CC-chemokines, the serum levels of IL-8/CXCL8 showed a significant increase (p < 0.05) in the allergic group compared to the non-allergic subjects. Interleukin 4 levels were similar in both groups. In the sera of allergic patients, we have also detected significantly elevated levels of ragweed-specific IgE and IgG. However, decreased serum concentrations of the four CC-chemokines and elevated levels of IL-8/CXCL8 can be used as biomarkers for more accurate evaluation of the allergic status of patients with pollen allergy out of the season, to study the mechanisms for activation/inhibition of the subclinical allergic responses and for development of therapeutic strategies.

Specific allergen immunotherapy: effect on IgE, IgG4 and chemokines in patients with allergic rhinitis

BACKGROUND

Allergen-specific immunotherapy (SIT) is considered as the most effective treatment for Immunoglobulin E (IgE)-mediated allergies. However, how specific immunotherapy attenuates allergic responses is still not clear, but could potentially involve cytokines as well as IgG4-mediated responses. Based on the role of chemokines in IgE-mediated inflammation, we examined the SIT-induced chemokine response in patients with allergic rhinitis.

METHODS

We included 35 patients with allergic rhinitis; 20 patients received SIT and 15 patients were not treated with specific immunotherapy. The patients were followed for 3 years. Blood samples were collected before SIT and 3, 5, 7 and 21 weeks and 1, 2 and 3 years after the start of therapy. Total IgE, specific IgE, IgG4 and chemokine levels were assessed.

RESULTS

Our main findings were: (i) SIT was associated with an early increase in total and specific IgE during the first 7 weeks, with a subsequent decline, accompanied by a marked increase in specific IgG4 when IgE started to decline; (ii) these SIT-induced responses were accompanied by and in some degree correlated with increased plasma concentrations of the chemokines, monocyte chemoattractant protein (MCP)-1, and eotaxin; and (iii) within the SIT group, these correlations with chemokines were restricted to IgE and IgG4 against birch tree pollen.

CONCLUSION

Our findings further support a role for IgG4-mediated mechanisms in the beneficial effects of SIT in patients with allergic rhinitis (AR) and that increased levels of certain chemokines also could be of importance for the effect of such therapy.

Macrophage Inflammatory Protein-1 Production and Eosinophil Infiltration in Chronic Rhinosinusitis With Nasal Polyps

Objective:

Eosinophil recruitment to the nasal mucosa involves a number of chemokines. The aim of this study was to evaluate nasal secretion levels of macrophage inflammatory protein-1 alpha (MIP-1α) and MIP-1β and to correlate these levels with clinical characteristics and degree of eosinophilia in nonallergic and allergic patients with nasal polyposis (NP).

Methods:

Fourteen nonatopic and 14 atopic patients with NP were recruited for this cross-sectional study. Fourteen healthy subjects were included as controls. The concentrations of MIP-1α and MIP-1β in nasal secretions were measured by flow cytometry. Eosinophil counts were performed by cytological examination of the scraped nasal mucosa. We scored each of the 28 patients according to the nasal symptom score, endoscopic score, and computed tomography (CT) score.

Results:

We found significantly higher concentrations of MIP-1α in nasal fluid of nonallergic and allergic NP patients compared to control subjects. In nonallergic patients, we found positive correlations between MIP-1α levels and endoscopic score, CT score, and the percentage of eosinophils.

Conclusion:

MIP-1α may play a role in eosinophil recruitment in NP. Our results suggest that the measurement of MIP-1α in nasal secretions could be useful in evaluating the degree of eosinophil inflammation and severity of disease in nonallergic patients.

Advances in asthma drug discovery: evaluating the potential of nasal cell sampling and beyond

INTRODUCTION

Inhaled corticosteroid anti-inflammatory therapy is effective at controlling disease symptoms of asthma, but a subset of patients remains symptomatic despite optimal treatment, creating a clear unmet medical need. Moreover, none of the currently available drugs for asthma are really disease-modifying or curative. Although murine models of asthma, based on transgenic and knockout animals, may offer an integrated pathophysiological system for studying the characteristics of airway inflammation and hyperresponsiveness, these alterations are noteworthily different compared with those observed in asthmatic patients. Since a clear functional and inflammatory relationship between the nasal mucosa and bronchial tissue in patients suffering from asthma and allergic rhinitis has been recognized, using preclinical models based on human nasal cells sampling might support a prompt and effective anti-inflammatory drug discovery in asthma.

AREAS COVERED

The authors provide a review, which discusses the potential role of nasal cell sampling and its application in advanced drug discovery for asthma. The contents range from the similarities and differences between asthma and allergic rhinitis up to artificial airway models based on sophisticated human lung-on-a-chip devices.

EXPERT OPINION

Nasal cell sampling and processing have reached a great potential in asthma drug discovery. The authors believe that models of asthma, which are based on human nasal cells, can provide valuable indications of proof of pharmacological and potential therapeutic efficacy in both preclinical and early clinical settings.

A study of elevated interleukin-8 (CXCL8) and detection of leukocyte migration inhibitory activity in patients allergic to beta-lactam antibiotics

BACKGROUND

The leukocyte migration test (LMT) is effective in identifying the causative drug in drug allergies. Both leukocyte migration activating activity (LMAA) and leukocyte migration inhibitory activity (LMIA) are involved in the development of drug allergies. However, no cytokines associated with LMIA have been identified to date. Because CXCL8 played an important role in neutrophil infiltration and activation, we performed the LMT and measured CXCL8 levels in patients with hypersensitivity to beta-lactam antibiotics (beta-lactams) and antipyretic analgesics (APAs) and investigated the pathogenic mechanism of hypersensitivity to these drugs.

METHODS

The LMT was performed according to an improved version of the agarose plate method and CXCL8 levels in the reacted solution that had been stored as described were measured using a solid-phase sandwich enzyme-linked immunosorbent assay.

RESULTS

Migration index (MI) values for the LMT were 77.7 ± 11.7 for patients with hypersensitivity to beta-lactams and 83.6 ± 1.9 for those with hypersensitivity to APAs. The CXCL8 concentrations were significantly higher in patients after beta-lactams administration (175.9 ± 71.2 ng/mL) than those without beta-lactams administration (48.3 ± 34.9 ng/mL). The CXCL8 concentrations were significantly lower in patients after APAs administration (41.7 ± 24.3 ng/mL) than those without APAs administration (63.1 ± 30.2 ng/mL).

CONCLUSIONS

Increased CXCL8 levels produced by beta-lactams administration were accompanied by LMIA. CXCL8 may be involved in LMIA and play a role in beta-lactam allergies. In contrast, the LMIA detected in patients with allergies to APAs may be a cytokine or chemokine other than CXCL8.

Lower airway disease in asthmatics with and without rhinitis

STUDY OBJECTIVES

The purpose of this study was to determine if asthma with rhinitis and asthma without rhinitis represent distinct forms of disease.

DESIGN

We performed a prospective cross-sectional study.

PARTICIPANTS

The study included healthy controls, participants with asthma without rhinitis, and participants with both asthma and rhinitis. Interventions We compared lung function and airway inflammation between the three groups of participants.

RESULTS

We recruited 32 participants: 12 normals, 8 asthmatics without rhinitis, and 12 with rhinitis. Compared to asthmatics with rhinitis, asthmatics without rhinitis had more severe airflow limitation (FEV(1)/FVC = 60.6% [IQR = 22.8] vs. 74.8% [IQR = 7.8] and fewer induced sputum eosinophils (2.8 [IQR = 5.8] and 9.6 [IQR = 23.8], respectively). Sputum interleukin-6 correlated inversely with lung function measured by postbronchodilator FEV(1) in the study cohort (Spearman correlation coefficient = -0.55, p < 0.01).

CONCLUSIONS

Asthmatics without rhinitis tend to have lower lung function and less eosinophilic inflammation in the lung. This small study suggests that asthmatics without rhinitis represent a distinct phenotype of asthma in which low lung function is dissociated from eosinophilic cellular inflammation, and it suggests that larger studies addressing this phenotype are warrented.

The effects of grass pollen allergoid immunotherapy on clinical and immunological parameters in children with allergic rhinitis

Allergoid immunotherapy is a new form of allergen immunotherapy allowing safe administration of high allergen doses. There is limited information on the effects of allergoid immunotherapy in children with allergic rhinitis. To investigate the immunological and clinical effects of allergoid immunotherapy in children with allergic rhinitis due to grass pollen allergy. Children with allergic rhinitis were assigned to allergoid immunotherapy (n = 27) or control (n = 26, no immunotherapy) groups. Children in the immunotherapy group received seven injections of grass pollen allergoid immunotherapy before grass pollen season and continued to receive maintenance immunotherapy for 27 months. All patients were offered a pharmacotherapy regimen to be used on demand during the pollen seasons. Clinical and laboratory parameters were compared between the immunotherapy and control groups. The rhinoconjunctivitis symptom-medication score and asthma symptom score were lower in the immunotherapy group after 1 yr of maintenance immunotherapy (p < 0.01 for both). Skin test reactivity and nasal reactivity as determined by nasal provocation testing for grass pollen were significantly decreased after 1 yr of immunotherapy (p < 0.001 for both). The seasonal increase in bronchial reactivity and nasal lavage eosinophil cationic protein levels were prevented after the first year of immunotherapy (p < 0.05 for both). The seasonal increase in immunoglobulin (Ig)E decreased (p < 0.05) and grass-specific IgG, IgG(1) and IgG(4) increased significantly already at the end of the seven-injection build-up therapy (p < 0.001, for all). Interleukin (IL)-4 levels in the culture supernatants showed a steady decline from baseline at first and second year of immunotherapy (p < 0.001) but remained unchanged in the control group. Allergoid immunotherapy is an effective method in the treatment of grass pollen-induced allergic rhinitis in children and prevents the seasonal increase in bronchial hyper-reactivity. Changes in specific IgE and IgG levels and decreased IL-4 production in peripheral blood mononuclear cell culture supernatants may account for the observed clinical effects.

Salivary levels of CGRP and VIP in rhinosinusitis and migraine patients

BACKGROUND

Secretion of calcitonin gene-related peptide (CGRP) from trigeminal nerves and vasoactive intestinal peptide (VIP) from parasympathetic nerves is involved in the pathophysiology of migraine and rhinosinusitis. Analysis of these neuropeptides in human saliva samples can be used as markers of trigeminal and parasympathetic nerve activity in patients between and during attacks as well as in response to specific treatments.

OBJECTIVE

To compare the amount of trigeminal sensory and parasympathetic nerve activation by measuring CGRP and VIP levels in the saliva of subjects experiencing noninfectious allergic rhinosinusitis, migraine with sinus symptoms, and no symptoms.

METHODS

Subjects were enrolled in three groups. Group A: subjects without a history of migraine, "sinus" headache, or allergic rhinosinusitis within the previous 6 months. Group B: subjects with chronic recurrent noninfectious rhinosinusitis and no history of migraine or "sinus" headache. Group C: subjects with self-described "sinus" headaches whose symptoms met International Headache Society diagnostic criteria (1.1 or 1.2) for migraine. The total amount of CGRP and VIP present in saliva collected under normal, pathological, and therapeutic conditions was determined by radioimmunoassay. Neuropeptide levels were normalized to total volume and amount of protein, and levels were correlated to onset and change in clinical symptoms.

RESULTS

Total volume, total protein, and CGRP and VIP levels did not significantly change in saliva collected on consecutive days in the clinic and at the subject's home, respectively. No appreciable change in baseline salivary levels of CGRP and VIP was detected in control subjects. However, baseline salivary levels of CGRP and VIP were significantly elevated between attacks in allergic rhinosinusitis and migraine subjects compared to control values. For rhinosinusitis subjects, the amount of CGRP and VIP during attacks returned to baseline values following treatment with pseudoephedrine and relief of symptoms. Similarly, CGRP and VIP levels during a migraine headache were significantly reduced within 2 hours after sumatriptan treatment and reported symptom relief.

CONCLUSION

Correlation of CGRP and VIP saliva levels observed in our study supports physiologically coordinated regulation of trigeminal and parasympathetic nerve activation in allergic rhinosinusitis and migraine patients between and during attacks as well as following treatment. Furthermore, our findings demonstrate that analysis of human saliva neuropeptides may provide a semiquantitative index of pathological and therapeutic states and, therefore, function as a clinical model for studying neuronal mechanisms involved in migraine and rhinosinusitis.

Factors contributing to nasal allergic late phase eosinophilia

OBJECTIVE

This study focused on factors contributing to eosinophilia after intranasal allergen challenge.

METHODS

Nasal secretions of 13 allergic individuals were gained over a period of 8 hours after nasal allergen challenge. Early and late phase reactions were determined by acoustic rhinometry and changes of volume and total protein in nasal secretions. Eosinophilia was demonstrated by nasal eosinophilic cationic protein. Interleukin (IL)-5; the chemokines IL-8, monocyte chemotactic protein (MCP)-1 and MCP-3, and eotaxin; soluble vascular cell adhesion molecule 1 (sVCAM-1); and the leukotriene C4 (LTC4) were analyzed by enzyme-linked immunosorbent assay for their suggested impacts on tissue eosinophilia.

RESULTS

By means of rhinometry, we observed in 69% an alternating type of late phase response, followed by a bilateral (15%) or unilateral (8%) type. A biphasic kinetic could be demonstrated by changes in nasal volume and total protein of nasal secretions, reflecting the early and late phase responses. A typical late phase kinetic was observed for IL-5, MCP-1, eotaxin, sVCAM-1, and LTC4. Interleukin 8 was characteristic for early phase reaction but increased in late phase as well. We could not detect any MCP-3 in our samples.

CONCLUSIONS

Our data point to a relevant role of the T(H)2 cytokine IL-5; of the chemokines IL-8, MCP-1, and eotaxin; of the adhesion molecule sVCAM-1; and of the leukotriene LTC4 for the allergic late phase eosinophilia.

A study of the effectiveness of chemosurgery with trichloroacetic acid for Japanese cedar pollenosis in terms of the chemical mediator levels in the nasal discharge and results of nasal provocation testing

OBJECTIVE

The purpose of the present study was to investigate the effectiveness of chemosurgery with 80w/v% trichloroacetic acid (TCA) for the treatment of Japanese cedar pollenosis. The effectiveness of this treatment was evaluated in terms of the levels in the nasal washings of the chemical mediators histamine and eosinophil cationic protein, and the reactivity in the nasal provocation test.

METHODS

Patients of cedar pollenosis were divided into two groups, the TCA-treated group (n=90) and the group that was not treated with TCA (nonTCA-treated group) (n=79), according to whether or not they received TCA treatment. In both the groups, the levels of the two aforementioned mediators in the nasal washings were measured during the pollen dispersal season. In addition, allergen provocation tests were performed using the disk method in volunteers from both the groups during the non-pollen dispersal season. The results of the above two determinations were compared statistically between the two groups.

RESULTS

The results revealed significantly lower levels of the two mediators in the TCA-treated group than in the nonTCA-treated group (p<0.01). There was also a greater tendency for the subjects in the TCA-treated group as compared to those in the nonTCA-treated group to show negative reactivity in the allergen provocation test (p<0.01).

CONCLUSION

Regional suppression of the allergic reaction to Japanese cedar pollen appears to occur as a result of chemosurgery with TCA performed as a day surgery.

Low levels of CC16 in nasal fluid of children with birch pollen-induced rhinitis

BACKGROUND

Clara cell protein 16 (CC16; secretoglobin 1A1) is an anti-inflammatory protein mainly expressed in the epithelial cells in the airways.

OBJECTIVE

To compare the levels of CC16 in nasal lavage (NAL) from children with intermittent allergic rhinitis and healthy controls and to study the effect of a local steroid.

METHODS

Thirty schoolchildren with birch pollen allergy and 30 healthy controls from the same schools were included in the study. The NAL fluid was collected before the season, during the birch pollen season and, for the patients, after 1 week of treatment with a local steroid. Symptom scores were obtained on every occasion. CC16 and eosinophil cationic protein (ECP) were analyzed with enzyme-linked immunosorbent assay.

RESULTS

The nasal fluid levels of CC16 were significantly lower in patients than in controls, before and during pollen season. Before the season, the median CC16 concentrations were 9.1 (range 1.1-117) microg/l in patients and 25.7 (6.1-110.2) microg/l in controls. During the season, the median CC16 concentrations in nasal fluid were 12.9 (2.3-89.7) microg/l in the allergic children and 22.0 (9.5-90.1) microg/l in the healthy controls (P = 0.0005). Symptom scores, nasal fluid eosinophils and ECP were higher in patients during the season. Treatment with a local steroid did not change the CC16 levels.

CONCLUSIONS

Nasal fluid CC16 levels were lower in children with birch pollen-induced allergic rhinitis than in healthy controls both before and during the pollen season. We speculate that reduction in anti-inflammatory activity by CC16 may contribute to the pathogenesis of allergic rhinitis.

Bet v 1-specific IgA increases during the pollen season but not after a single allergen challenge in children with birch pollen-induced intermittent allergic rhinitis

Allergen-specific immunoglobulins of the Immunoglobulin A (IgA) type have been found in the nasal fluid of patients with allergic rhinitis. IgA may play a protective role, but there are also data which show that allergen-specific IgA can induce eosinophil degranulation. The aim of this study was to quantitate Bet v 1-specific IgA in relation to total IgA in the nasal fluid of children with birch pollen-induced intermittent allergic rhinitis and healthy controls, after allergen challenge and during the natural pollen season. Eosinophil cationic protein (ECP), Bet v 1-specific IgA and total IgA were analyzed in nasal fluids from 30 children with birch pollen-induced intermittent allergic rhinitis and 30 healthy controls. Samples were taken before the pollen season, after challenge with birch pollen and during the pollen season, before and after treatment with nasal steroids. During the pollen season, but not after nasal allergen challenge, Bet v 1-specific IgA increased in relation to total IgA in children with allergic rhinitis. No change was found in the healthy controls. The ratio of Bet v 1-specific IgA to total IgA increased from 0.1 x 10(-3) (median) to 0.5 x 10(-3) in the allergic children, p < 0.001. No change was seen after treatment with nasal steroids, although symptoms, ECP and eosinophils were reduced. In conclusion, allergen-specific IgA in relation to total IgA increases in nasal fluids during the pollen season in allergic children but not in healthy controls. These findings are compatible with the hypothesis that allergen-specific IgA plays a role in the allergic inflammation and further studies are needed to clarify the functional role of these allergen-specific antibodies.

Effect of anti-immunoglobulin E on nasal inflammation in patients with seasonal allergic rhinoconjunctivitis

BACKGROUND

Binding of allergens to IgE on mast cells and basophils causes release of inflammatory mediators in nasal secretions.

OBJECTIVE

The combined effect of specific immunotherapy (SIT) and omalizumab, a humanized monoclonal anti-IgE antibody, on release of eosinophilic cationic protein (ECP), tryptase, IL-6, and IL-8 in nasal secretion was evaluated.

METHODS

Two hundred and twenty five children (aged 6-17 years) with a history of seasonal allergic rhinoconjunctivitis induced by birch and grass pollen were randomized into four groups: either birch- or grass-pollen SIT in combination with either anti-IgE or placebo. Complete sets of nasal secretion samples before treatment Visit 1 (V1), during birch- (V2) and grass (V3)-pollen season and after the pollen season (V4) were collected from 53 patients.

RESULTS

A significant reduction in tryptase only was seen in the anti-IgE-treated group at V2 (P<0.05) and V4 (P<0.05) compared with the placebo group. During the pollen season, patients with placebo showed an increase of ECP compared with baseline (V2: +30.3 microg/L; V3: +134.2 microg/L, P< 0.005; V4: +79.0 microg/L, P< 0.05), and stable levels of tryptase, IL-6 and IL-8. Treatment with anti-IgE resulted in stable ECP values and a significant decrease of tryptase compared with V1 (baseline): V2: -80.0 microg/L (P< 0.05); V3: -56.3 microg/L, which persisted after the pollen season with V4: -71.6 microg/L (P< 0.05). After the pollen season, a decrease of IL-6 was observed in both groups (V4 placebo group: -37.5 ng/L; V4 anti-IgE group: -42.9 ng/L, P< 0.01).

CONCLUSION

The combination of SIT and anti-IgE is associated with prevention of nasal ECP increase and decreased tryptase levels in nasal secretions.

Untreated chronic rhinosinusitis: a comparison of symptoms and mediator profiles

OBJECTIVES/HYPOTHESIS

Since the early 1990s, the knowledge of inflammatory mediators involved in chronic rhinosinusitis has increased extensively. However, until the present no data on trends in mediator levels in the natural course of the exacerbation-free interval of chronic rhinosinusitis have been published. The purpose of the study was to examine how levels of inflammatory mediators and clinical findings in chronic rhinosinusitis relate over time in the absence of acute exacerbation.

STUDY DESIGN

Prospective study.

METHODS

The authors investigated 12 untreated patients with chronic rhinosinusitis and repeated clinical examinations and measurements of inflammatory mediators in the nasal mucosa (messenger RNA [mRNA]of interleukin-1beta; interleukins 3, 5, 6, and 8 [IL-3, IL-5, IL-6, and IL-8]; interferon gamma; tumor necrosis factor-alpha [TNF-alpha]; monocyte chemotactic proteins 1, 3, and 4 [MCP-1, MCP-3, and MCP-4]; and granulocyte-macrophage colony-stimulating factor [GM-CSF]), as well as measurements of peptido-leukotriene [PLT] and prostaglandin E2 [PGE2]) in nasal secretion over a period of 4 weeks.

RESULTS

Clinically speaking, the symptom score significantly improved over the period of 4 weeks, whereas other clinical parameters (computed tomography score, endoscopy score, rhinomanometric values, saccharine transport time, ciliary beat frequency, and olfaction) varied insignificantly. Regarding proinflammatory and inflammatory mediators, only mRNA of IL-1beta, IL-6, IL-8, MCP-1, and TNF-alpha were detected in relevant amounts in nasal mucosa, and their levels decreased only insignificantly over the 4-week period. In nasal secretion, a slight decrease of PGE2 and PLT levels was observed over the same time period.

CONCLUSION

Subjective symptoms may show a spontaneous improvement of approximately 25% in patients with so-called "stable" chronic rhinosinusitis over a 4-week period, whereas objective clinical parameters vary insignificantly. Messenger RNA of IL-1beta, IL-6, IL-8, MCP-1, and TNF-alpha, as well as PLT and PGE2 levels, are detectable and appear to play a role in the persistence of inflammation in chronic rhinosinusitis. Their levels decrease only insignificantly over time, even in the absence of acute exacerbation of disease, possibly rendering the mucosa more prone to recurrent acute episodes.

The effect of recombinant interleukin-8 on eosinophils' and neutrophils' migration in vivo and in vitro

BACKGROUND

Interleukin-8 (IL-8) is a chemokine that causes chemotaxis of neutrophils, eosinophils and lymphocytes in vitro; however, its role as a chemoattractant in allergic inflammation is unclear. The objective of this study was to investigate the effect of nasal instillation of IL-8 on the influx of inflammatory cells.

METHODS

Twelve patients suffering from seasonal allergic rhinitis hypersensitive to grass pollens, with average age 30.1 +/- 2.67 years were challenged both with diluent for IL-8 and IL-8 on a subsequent day, in two phases: before the pollen season (unprimed mucosa) and during the season (primed mucosa). The number of neutrophils, eosinophils and myeloperoxydase (MPO) levels in the nasal fluid collected after IL-8 or placebo challenge were determined.

RESULTS

Challenge with IL-8 of primed nasal mucosa induced a significant influx of neutrophils (29 x 10(4) cells/ml at 0.5 h, 251 x 10(4) at 2 h and 334 x 10(4) at 3 h). Number of eosinophils in comparison with diluent challenge was not significant. There was no difference in MPO levels in the nasal lavage between IL-8 and diluent challenge of unprimed and primed mucosa. We did not find the relationship between MPO levels and the neutrophils number in the lavage (rank Spearman factor, RS = 0.258, P = 0.42).

CONCLUSION

We have demonstrated that IL-8 causes influx of neutrophils but not eosinophils into nasal mucosa in vivo. MPO level seems to be of little value as a marker of neutrophil influx into nasal mucosa.

Interleukin-4 and interferon-gamma gene expression in summer pasture-associated obstructive pulmonary disease affected horses

We hypothesised that horses affected with summer pasture-associated obstructive pulmonary disease (SPAOPD) react to an allergen or allergens in their summer environment that is either absent or present at lower levels in their winter environment; and that such allergens stimulate SPAOPD-affected horses to produce a different T helper lymphocyte cytokine profile from that of control horses. The primary objective of this study was to determine the cytokine mRNA profile of T helper lymphocytes obtained from summer pasture-associated obstructive pulmonary disease (SPAOPD) affected horses when 1) the horses were showing signs of disease (summer) and 2) they were in clinical remission (winter). A further objective was to determine the differences between cytokine mRNA T helper lymphocyte profiles of control and affected horses in the summer and winter seasons. Interleukin 4 (IL-4) and interferon-gamma (IFN-gamma) mRNA expression levels were increased in bronchoalveolar lavage fluid (BALF) and peripheral blood mononuclear cell (PBMC) samples of affected horses during disease expression. No significant amounts of IL-5 mRNA were detected in any of the samples. These results suggest that there is an allergic component to SPAOPD of horses and that appropriate manipulation of the immune system could offer hope for treatment and prevention of the disease in the future. Further research studies will be needed to determine the most appropriate treatments to use to alter the antigen-stimulated cytokine profile being expressed by SPAOPD-affected horses or to alter the effects that these cytokines produce.

Eotaxin but not MCP-3 induces eosinophil influx into nasal fluid in allergic patients

BACKGROUND

Eotaxin and MCP-3 (CC chemokines), owing to their preferential action on eosinophils, seem to be the very importance in the patophysiology of allergic rhinitis and asthma. The purpose of this study was to examine the effect of intranasally administered eotaxin and MCP-3 after specific allergen priming on the influx of inflammatory cells and their soluble mediators into the nasal mucosa.

METHODS

Eotaxin and MCP-3 have been applied intranasally at the increasing doses of 1, 5 and 10 microg to allergic patients after allergen priming. The 'nasal pool' technique was used. The cell count and biochemical parameters in nasal lavage were evaluated before 30 min, and 4 and 24 h after the challenge with chemokines.

RESULTS

Both eotaxin and MCP-3 induced the increase in clinical 'score' lasting till 24 h. Eosinophil influx into nasal mucosa after provocation with eotaxin was also observed. The challenge with MCP-3 did not induce any significant changes in nasal lavage fluid.

CONCLUSIONS

Eotaxin is likely to play an important role in the pathogenesis of allergic conditions in humans. MCP-3 did not induce inflammatory cell influx into nasal mucosa. The role of this chemokine in the pathogenesis of allergic inflammation is difficult to assess and requires further studies.

Mode of action of intranasal corticosteroids

The mode of action of intranasal corticosteroids (INCS) is complex. It is not known whether INCS penetrate the nasal mucosa or act on target cells; however, their low systemic activity supports the concept of local action on nasal mucosa. This local effect can nonetheless influence a variety of inflammatory cells and their mediators such as epithelial cells, lymphocytes, basophils, mast cells, and Langerhans cells. Corticosteroid-induced inhibition of immunoglobulin E-dependent release of histamine is a possible but unproven mode of action. Epithelial cells are an important target for corticosteroids, and INCS concentration is high at the epithelial surface. INCS may combine with the corticosteroid receptors in epithelial cells, which are then expelled into the airway lumen together with the dead epithelial cells or migrating inflammatory cells. A reduced influx of mediator cells may explain some of the effects of INCS on rhinitis symptoms, but it cannot explain all of the effects because INCS also reduce the early-phase sneezing and rhinorrhea after an allergen challenge outside the pollen season. In this situation, the number of surface mast cells/basophils is very low, as it is in the absence of allergic rhinitis. The mechanism by which INCS treatment of allergic rhinitis reduces itching, sneezing, and rhinorrhea, the characteristic symptoms of an early-phase response involving mast cell release of histamine, remains to be determined. Studies should be conducted to characterize the broad range of mechanisms by which INCS produce their therapeutic effects in allergic rhinitis.

Allergic rhinitis: not purely a histamine-related disease

Allergic rhinitis is an inflammatory disorder of the nasal mucosa typified by the symptoms of nasal itch, sneeze, anterior nasal secretions, and nasal blockage. These symptoms arise from the interaction between mediators and neural, vascular, and glandular structures within the nose. Nasal itch, sneezes, and rhinorrhoea are predominantly neural in origin, while nasal obstruction is predominantly vascular. Nasal biopsy studies show accumulation of eosinophils within the lamina propria and epithelium and an increase in tissue and cell surface basophils in both seasonal and perennial allergic rhinitis. These cells are in an activated state. Within the epithelium, increased numbers of mast cells, T cells and Langerhans' cells, which induce T-cell activation, are found. The accumulation of these cells can be linked to chemokine and cytokine generation by the epithelial cells themselves. Thus, the tissue cell recruitment is orchestrated by activated mast cells, T cells, and epithelial cells, with the recruited tissue eosinophils also contributing to their persistence at this site through autocrine mechanisms. Mast cells generate an array of mediators including histamine, tryptase, leukotrienes, and prostaglandins. Histamine is also generated by basophils. Eosinophils and basophils contribute to the leukotriene synthesis within the tissue. Histamine nasal insufflation induces nasal itch, sneeze, and rhinorrhoea as well as nasal blockage, thereby reproducing all the symptoms of allergic rhinitis. These effects are primarily mediated by H1-receptors, and H1-receptor antagonists are a prominent treatment. Antagonism of histamine at these receptors reduces symptoms by about 40-50%, with the greatest effect on the neurally mediated responses. Thus, histamine is a major mediator of allergic rhinitis, but not the sole contributor. Nasal insufflation with leukotrienes, prostaglandins, or kinins is associated with the development of nasal blockage. These mediators act primarily on the nasal vasculature and, in this respect, leukotrienes are potent mediators. Leukotrienes also induce plasma protein exudation, which contributes to the anterior nasal secretions. Studies with combination products have suggested that modifying the effects of both leukotrienes and histamine has complementary effects in relieving nasal symptoms, indicating that both these mediators are relevant to disease expression.

Attenuation of interleukin 8-induced nasal inflammation by an inhibitor peptide

Polymorphonuclear neutrophils (PMNs) infiltrate tissue in response to chemoattractants, including interleukin 8 (IL-8). Infiltrating PMNs clear microorganisms but also cause tissue damage. We previously reported the presence in human bronchial lavage of a peptide that inhibits PMN functions. The current project assessed (1) effects of a synthetic analog of this peptide (synthetic neutrophil inhibitor peptide, SNIP) on IL-8-induced nasal inflammation in humans, (2) effects of SNIP on PMN apoptosis and chemotaxis, (3) specific binding of SNIP to PMNs, and (4) evidence of larger molecules with the SNIP sequence. Results show that SNIP attenuates IL-8-induced nasal inflammation, inhibits in vitro PMN chemotaxis to IL-8, and accentuates PMNs apoptosis. PMNs contain specific SNIP-binding sites and the integrin CR3 (CD11b/CD18), or a CR3-associated molecule, is one SNIP-binding molecule. Chemotaxis to IL-8 is most potently inhibited by SNIP in the presence of fibrinogen, a CR3 ligand. Antiserum against the SNIP sequence recognizes a 70-kDa protein in bronchoalveolar lavage and an anti-SNIP immunoaffinity column binds a 70-kDa protein in U937 cell culture supernatant. U937 cell mRNA contains a 1.8-kb transcript detected with degenerate oligonucleotides designed from the SNIP sequence. These studies demonstrate that a synthetic inhibitor peptide can attenuate in vivo nasal inflammation through downregulatory effects on PMNs.

Retrospective study on fluticasone propionate aqueous nasal spray efficacy in patients with allergic rhinitis: evaluation of clinical and laboratory parameters

BACKGROUND

In allergic rhinitis, allergenic stimulation causes the release of various mediators that induce symptoms and the development of chronic inflammation, which, in turn, is caused by cells involved in the late phase of inflammation, such as eosinophils. The eosinophils also cause damage at the mucosal level through the secretion of eosinophil cationic protein and other preformed factors contained in their granules. The objective was to verify the efficacy of fluticasone propionate aqueous nasal spray in patients with allergic rhinitis; in a retrospective study, we have evaluated mediators of inflammation, making correlations with the clinical symptoms score during and outside the pollen season.

METHODS

Forty patients with allergic rhinitis and 15 normal controls were included in our study. Eosinophil cationic protein, eosinophil chemotactic activity, and blood and nasal lavage eosinophil count were evaluated as laboratory parameters.

RESULTS

We found a significant increase in nasal lavage levels of eosinophil cationic protein in allergic patients, and this was strictly correlated with the clinical symptoms score. No differences were found in the eosinophil count of allergic patients and in the serum eosinophil cationic protein of patients sensitized to seasonal allergens in comparison with normal subjects. By contrast, an increase in serum eosinophil cationic protein level was found in patients sensitized to perennial allergens. After topical administration of fluticasone propionate aqueous nasal spray, a reduction in nasal lavage eosinophil cationic protein secretion was obtained with a reduction of eosinophil chemotactic activity at the local level. This reduction correlated with an improvement of clinical symptoms.

CONCLUSIONS

The clinical improvement and reduction in nasal lavage eosinophil cationic protein and eosinophil chemotactic activity after administration of fluticasone propionate aqueous nasal spray further confirms the role of this treatment in allergic rhinitis.

Monocyte chemoattractant peptide-1 expression during cutaneous allergic reactions in mice is mast cell dependent and largely mediates the monocyte recruitment response

BACKGROUND

Macrophages and infiltrating monocytes comprise the largest population of cells within the airways of patients with allergic asthma. Both become activated and thus contribute to the pathologic features of allergic reactions, but the mechanism by which they are recruited has not been well documented.

OBJECTIVE

Our purpose was to assess the role of the CC chemokine monocyte chemotactic peptide-1 (MCP-1) in monocyte recruitment during allergic reactions in mice.

METHOD

We used immunohistochemistry and Northern blotting to assess MCP-1 expression, selective mast cell reconstitution of mast cell-deficient W/W(v) mice to demonstrate the mast cell dependence of MCP-1 expression and monocyte recruitment and neutralizing anti-MCP-1 antibodies to block monocyte recruitment during cutaneous allergic reactions.

RESULTS

MCP-1 was expressed largely by resident dermal cells within the allergic lesions at 4 hours after challenge, followed within several hours by an influx of monocytes; at 10 hours after challenge monocytes comprised a substantial proportion of the infiltrating cells at the nidus of the response. Mast cell-reconstituted, but not mast cell-deficient W/W(v) mice expressed MCP-1 transcripts and developed monocyte infiltrates after allergen challenge. Finally, anti-MCP-1 antibody treatments reduced by approximately 63% the influx of monocytes into the reaction sites.

CONCLUSIONS

These data clearly demonstrate the mast cell dependence of the MCP-1 expression and the monocyte influx and establish a substantial, but not exclusive, causal relationship between these 2 events.

NOVEL THERAPEUTIC APPROACHES FOR ALLERGIC RHINITIS

The last 2 decades have witnessed enormous changes in our understanding of allergic rhinitis. As we have begun to unravel the complex underlying immunologic and inflammatory pathophysiology of the disease, new therapeutic strategies as well as specific molecular and cellular constituents have emerged as potential targets for clinical intervention. These efforts also have shed light on the mechanisms by which current antiallergy medications act—or sometimes fail to be effective.7, 31, 51, 89 The similar pathophysiologic basis for allergic rhinitis and the often comorbid condition, asthma, was underscored in the recently published American Thoracic Society Workshop Summary on the Immunobiology of Asthma and Rhinitis: Pathogenic Factors and Therapeutic Options.¹⁸ In his conclusion, workshop chair, Thomas Casale,¹⁸ counsels readers to consider that “…allergic asthma and rhinitis represent a systemic disease affecting two organs, the lung and the nose. Asthma and allergic rhinitis share many of the same pathogenic factors, but they operate in different parts of the airway. Inflammatory cells and mediators are often the same, and there may be common alterations that occur in the immune system.” Thus, therapeutic strategies and potential therapeutic agents found to be beneficial in the treatment of one airway target may show similar effects in the other. For this reason, and because many of the therapies now being developed are at early stages in their evolution, physicians interested in rhinitis therapy also must examine what is known about these agents in asthma.

One avenue of active research has been the role of leukotrienes and other mediators in the pathophysiology of asthma and rhinitis. Three leukotriene modifiers now have been approved for the treatment of asthma in the United States; their potential use in the treatment of rhinitis has been a focus of considerable speculation and investigation. An early “day in the park” study showed that with antileukotriene therapy, patients with rhinitis had demonstrable improvements in their rhinitic symptoms.²⁹ Roquet et al⁸³ reported that in the treatment of asthma, there was a synergistic effect when an antileukotriene agent and an antihistamine were used, compared with either drug alone. A product combining an antileukotriene with an antihistamine is currently under development.

The most exciting developments, however, may be in the immunology arena. As described by Baraniuk elsewhere in this issue, the pathophysiology of allergic rhinitis is highly complex. Multiple interacting, interdependent, and redundant pathways and molecular and cellular constituents are involved in the pathogenesis of allergic rhinitis.

Briefly, exposure of the nasal mucosa to allergen in a sensitized individual leads to the release and further production of inflammatory mediators and the release of cytokines.⁵ These released cytokines activate endothelial cells, thereby inducing expression of adhesion receptors on the cell surface and initiating a cascade of events that facilitates transendothelial migration of inflammatory cells. T lymphocytes also are activated by these cytokines. Within a given tissue, specific patterns of cytokines are released, dependent on the dominant subset of local T lymphocytes. These, in turn, lead to the preferential activation and recruitment of specific inflammatory cells and the characteristic cellular inflammation observed in allergic rhinitis.

Low levels of interferon-gamma in nasal fluid accompany raised levels of T-helper 2 cytokines in children with ongoing allergic rhinitis

The T-helper 2 (Th2) cytokines interleukin-(IL-) 4, IL-5, IL-6, IL-10 and the Th1 cytokine IFN-gamma and their associations with eosinophil, eosinophil cationic protein (ECP) and immunoglobulin (Ig) E were studied in nasal lavage fluid from 60 school children with allergic seasonal rhinitis and 36 nonatopic healthy controls, before and during the pollen season. Eosinophil differential counts and IgE increased significantly in the patients during the pollen season. The eosinophil differential counts, ECP and IgE were all significantly higher during the season than in specimens simultaneously obtained from the nonatopic controls. Before season, the levels of ECP and IgE, but not eosinophils, were significantly higher in the patients than in the controls. During the season the nasal lavage fluid levels of IFN-gamma were significantly lower and the IL-4/IFN-gamma quotients significantly higher in the allergic than in the control children. In the allergic children, but not in the controls, the nasal fluid levels of the Th2 cytokines IL-4, IL-5 and IL-10 increased during the season, and together with IL-6, were correlated with the differential counts of eosinophils, and with the levels of ECP and IgE. These findings are compatible with the hypothesis that a deficient release of the Th1 cytokine IFN-gamma plays an important role in the pathogenesis of allergic inflammation. Regardless of whether the defective IFN-gamma secretion is primary or a consequence of suppression by other cytokines, it will in the atopic subjects enhance the release of Th2 cytokines, which in turn will facilitate the development of allergic inflammation.

Cetirizine counter-regulates interleukin-8 release from human epithelial cells (A549)

BACKGROUND

Cetirizine, a H1-receptor antagonist, exerts besides its well-known anti-allergic potential an array of anti-inflammatory activities. In particular epithelial cells activated in the presence of cetirizine showed a reduced ICAM-1 cell surface expression and a diminished release of sICAM-1.

OBJECTIVE

We wondered whether cetirizine might influence the release of interleukin-8 (IL-8) from human epithelial cells activated with agonists distinct from histamine.

METHODS

We used the human lung epithelial cell line A549 for our in vitro studies. IL-8 release was determined by IL-8 enzyme immunoassay, the intracellular staining for IL-8 and NF-kB was analysed by FACS analysis and IL-8 mRNA steady state level was studied by Northern blot analysis. Confluent epithelial cell monolayer were pre-incubated with cetirizine (0.01 -1.0 micromol/L) for 30 min and afterwards activated with pro-inflammatory cytokines (TNF-alpha IL-1beta, IL-6, IFN-gamma) or different agonists (PMA, NaF, respiratory syncytial virus [RSV]) for 24 h.

RESULTS

Epithelial cells stimulated with TNF-alpha IL-1beta, PMA and RSV, respectively, showed a significantly increased release of IL-8. Pre-incubation with cetirizine diminished the IL-8 release from cells activated with TNF-alpha or PMA in a significant manner. The reduced IL-8 release coincided with a diminished percentage of cells expressing IL-8. Northern blot analysis revealed a reduced steady state level of IL-8 mRNA in cells pretreated with cetirizine and stimulated with TNF-alpha. Furthermore, a decreased amount of accessible DNA-binding sites of the nuclear factor kappa B (NF-kB) was determined by FACS analysis.

CONCLUSIONS

These results suggest that cetirizine reduced the release of IL-8 from A549 cells stimulated with PMA and TNF-alpha, respectively, by lowering IL-8 gene expression. Therefore, cetirizine might exert anti-inflammatory effects beyond its H1-receptor antagonistic activity in the course of inflammatory respiratory tract disorders such as bronchial asthma and allergic rhinitis.

Allergic inflammation in upper and lower airways

OBJECTIVE

The primary reason for this review is to discuss the relationship between upper and lower airways at various levels with the emphasis on common pathophysiologic mechanisms, and how treatment of the upper airways will benefit the lower airways.

DATA SOURCES

The main source of information is derived from original articles and books, with an extensive bibliography included.

STUDY SELECTION

Studies were derived almost exclusively from articles and reviews in peer-reviewed journals.

RESULTS

The prevalence of rhinitis and asthma are both increasing. Common to both the upper and lower airways are the triggers, many of the inflammatory cells and mediators, and the treatment modalities. By contrast, there are organ-specific differences in the reaction to various stimuli in the nose or lung, with each organ manifesting its own vocabulary of response.

CONCLUSIONS

There are meaningful relationships between upper and lower airways at various levels of our understanding. Differential responses to medications help us better understand pathogenic mechanisms in rhinitis and asthma. Further, treatment of the upper airways provides additional benefit to the lower airways.

Comparison of the effects of fluticasone propionate, aqueous nasal spray and levocabastine on inflammatory cells in nasal lavage and clinical activity during the pollen season in seasonal rhinitics

BACKGROUND

Treatment options for allergic rhinitis include antihistamines, decongestants, anticholinergics, cromolyn sodium and corticosteroids. As the nose is a small organ, comprising less than 1% of total body mass and surface area, it seems logical to confine treatment of rhinitis to the diseased organ.

OBJECTIVE

To evaluate the effects of therapy with intranasal fluticasone propionate (FP), both on subjective symptoms and pathophysiological mechanisms, in rhinitis patients during pollen season when the patients were symptomatic.

METHODS

We used a double-blind, placebo (PLA)-controlled, randomized, double dummy, parallel group study of the effect of 6 weeks treatment. The double-blind comparison was made between the following three treatments: FP aqueous nasal spray, 200 microg taken once daily, levocabastine (LEV) nasal spray, 200 microg taken twice daily and PLA nasal spray. Clinical evaluation and the levels of cells and mediators in nasal washing were performed before and after treatments. Twenty-four patients (11 men and 13 women, aged 17-50 years, mean age 30.1 +/- 8.5) with strictly seasonal allergic rhinitis to Parietaria entered the study. Clinical evaluation and the levels of inflammatory cells (eosinophils and activated eosinophils, i.e. EG2+) and their mediators (tryptase, eosinophil cationic protein, eosinophil protein X and neutrophil myeloperoxidase) in nasal-lavage were performed before and after treatments.

RESULTS

Treatment with FP significantly increased, with respect to placebo, the percentage of days without sneezing (P < 0. 001), nasal blockage (P < 0.001), rhinorrhea (P < 0.001), nasal itching (P < 0.001). Furthermore, treatment with FP showed additional benefits with respect to LEV. The percentage of days without nasal blockage was significantly higher in the FP group that in the placebo group (P = 0.018). The same applied to rhinorrhea (P = 0.009). The percentages of days without sneezing and itching were instead not significantly different between the two groups. As expected, no significant differences were observed in baseline medians of the rhinitis symptom scores as well as in mean values of all mediators and eosinophils in nasal lavages of the various groups under study. After treatment the mean of subjective symptoms as well as all values in nasal lavage level fell significantly only in the FP group, whereas no significant changes were observed either in LEV or PLA groups. Accordingly, significant differences were observed at the end of the treatments between the values of fluticasone group vs LEV and PLA group values. Significant correlations between these values and symptom scores were found, according with literature data suggesting a pathogenetic role for these mediators and eosinophils in rhinitis.

CONCLUSION

FP (200 microg once daily) affords a significant degree of improvement in rhinitis control during pollen season, as measured by subjective and objective parameters, compared with LEV (200 microg twice daily) and PLA. The therapeutic benefits of intranasal FP are reflected in, and may be caused by, the decrease in nasal inflammatory cells.

Expression of monocyte chemotactic protein (MCP)-1, MCP-2, and MCP-3 by human airway smooth-muscle cells. Modulation by corticosteroids and T-helper 2 cytokines

We have demonstrated that, in addition to their contractile function, human airway smooth-muscle cells (HASMC) are able to express and to secrete chemokines of the monocyte chemotactic protein (MCP)/ eotaxin subfamily. This group of chemokines is believed to play a fundamental role in the development of allergic airway diseases such as asthma. The expression levels of MCP (MCP-1, -2, and -3) messenger RNA (mRNA) were compared with those of regulated on activation, normal T cells expressed and secreted (RANTES) mRNA in HASMC in culture. HASMC express MCP and RANTES mRNA after stimulation with interleukin (IL)-1beta, tumor necrosis factor-alpha, and interferon-gamma. MCP mRNA was maximal at 8 h, whereas RANTES mRNA expression was delayed to 24 h after stimulation. Further, significant differences were observed in the induction patterns of MCP and RANTES mRNA expression after stimulation with the individual cytokines. Dexamethasone (DEX) significantly inhibited cytokine-induced accumulation of MCP and RANTES mRNA, in contrast to IL-4, IL-10, and IL-13, which had no inhibitory effect on cytokine-induced chemokine expression. The cytokine-induced MCP mRNA expression in HASMC was associated with MCP release, which was inhibited by DEX and post-translationally by IL-4. HASMC can actively participate in the pathogenesis of asthma by the expression and release of chemokines, which are likely to play a critical role in the generation and regulation of the inflammatory response characteristic of allergic airway diseases.

Pathophysiology of the inflammatory response

Airway allergic reactions enlist diverse cells and a multitude of chemical mediators that are responsible for the clinical symptoms of allergic rhinitis and asthma. Experiments in vitro and in animal models, as well as increasingly numerous studies in atopic human subjects, are revealing that an orchestrated continuum of cellular activities leading to airway allergic inflammation is set in motion in genetically predisposed individuals at the first exposure to a novel antigen. This sensitization step likely depends on differentiation of and cytokine release by T(H)2 lymphocytes. Among T(H)2-derived cytokines, IL-4 potently enhances B-lymphocyte generation of immunoglobulin E antibodies. The attachment of these antibodies to specific receptors on airway mast cells sets the stage for an acute inflammatory response on subsequent antigen exposure because IgE cross-linking by a bound antigen activates mast cells to release numerous inflammatory mediators. These mast cell-derived mediators collectively produce acute-phase clinical symptoms by enhancing vascular leak, bronchospasm, and activation of nociceptive neurons linked to parasympathetic reflexes. Simultaneously, some mast cell mediators up-regulate expression on endothelial cells of adhesion molecules for leukocytes (eosinophils, but also basophils and lymphocytes), which are key elements in the late-phase allergic response. Chemoattractant molecules released during the acute phase draw these leukocytes to airways during a relatively symptom-free recruitment phase, where they later release a plethora of cytokines and tissue-damaging proteases that herald a second wave of airway inflammatory trauma (late-phase response). The repetition of these processes, with the possible establishment in airway mucosa of memory T lymphocytes and eosinophils that are maintained by paracrine and autocrine cytokine stimulation, may account for airway hypersensitivity and chronic airway symptoms.

Nasal reactivity to capsaicin in patients with seasonal allergic rhinitis during and after the pollen season

BACKGROUND

We aimed to study the participation of neurogenic mechanisms in nasal allergic inflammation by assessing the effect of neurogenic stimulation on the secretory and cellular responses of nasal mucosa in patients with allergic rhinitis.

METHODS

A group of patients suffering from seasonal allergic rhinitis was challenged intranasally with incremental doses of capsaicin (0.3, 3, 12 microg) during and after the pollen season. Clinical symptoms after provocations were monitored, and unilateral nasal lavages were obtained. The nasal lavage fluid (NAL) was assayed for concentration of total protein, albumin, lactoferrin, and number of leukocytes, following by differential count.

RESULTS

Capsaicin challenge during the pollen season produced greater congestion (P < 0.01) and rhinorrhea (P < 0.05) than after the season. The intensity of burning sensation (pain) was similar on both occasions. Capsaicin failed to increase albumin content in NAL both during and after the season. Total protein was increased only after the highest dose of capsaicin (P < 0.03) after the season. The number of eosinophils in basal lavages was higher during the season. During the season, the total number of leukocytes at least doubled in 7/12 patients and the percentage of eosinophils increased in 6/12 patients after the capsaicin challenge.

CONCLUSIONS

Our study demonstrated that during the symptomatic period the nasal mucosa of allergic patients is more susceptible to neurogenic stimulation, showing enhanced secretory and inflammatory (cellular) responses.

Interleukin-5 and interleukin-8 in relation to eosinophils and neutrophils in nasal fluids from school children with seasonal allergic rhinitis

The objectives of this study were to measure interleukins 5 and 8 (IL-5 and IL-8) in relation to eosinophils and neutrophils, in nasal lavage fluids from 60 school children with allergic rhinitis, and to determine the influence of treatment with a topical steroid (budesonide) on the levels of the two cytokines. Highly sensitive enzyme immunoassays were used to analyze IL-5 and IL-8. IL-5 levels and relative eosinophil counts in nasal lavage fluid increased significantly in patients with allergic rhinitis during the pollen season, compared with values obtained before the start of the season, and decreased significantly after treatment with budesonide. By contrast, no significant changes in IL-8 or neutrophils were found during the pollen season, nor did they decrease following treatment. In the untreated patients, IL-5 levels correlated significantly with eosinophil counts but not with neutrophil counts, whereas IL-8 levels correlated with neutrophil counts but not with eosinophil counts. After budesonide treatment, the correlation between IL-8 and neutrophils remained, and a correlation between IL-8 and eosinophils emerged. These findings support the concepts that IL-5 has a key role in regulating eosinophils and that IL-8 is important for the regulation of neutrophils. Whereas IL-5 and relative eosinophil counts are profoundly affected by topical steroid treatment, IL-8 and neutrophils are not demonstrably affected by such treatment. It is possible that neutrophils, through the release of IL-8, could be chemotactic for eosinophils in steroid-treated patients.

The MCP/eotaxin subfamily of CC chemokines

Migration of leukocytes from the bone marrow to the circulation, the primary lymphoid organs and inflammatory sites is directed by chemokines and specific receptor interactions. Besides the role of this group of low molecular weight cytokines in leukocyte attraction and activation, anti-HIV and hematopoietic activities were also attributed to chemokines. On the basis of the number and arrangement of the conserved cysteines, chemokines are subdivided in two multi-member families, namely the CXC and CC chemokines, whereas fractalkine (CX3C) and lymphotactin (C) are unique relatives. The CC chemokines possess four cysteines of which the first two are adjacent. Functionally, they form a rather heterogeneous family. Here, the focus is on the monocyte chemotactic proteins and eotaxin which, on a structural basis, can be considered as a CC chemokine subfamily. Not only the protein sequences, but also the gene structures, chromosomal location, biological activities and receptor usage exhibit considerable similarities. The review is complemented with a comparison of the biological functions of the MCP/eotaxin-subfamily in physiology and pathology.

Diagnosis and management of rhinitis

This article reviews the differential diagnoses for rhinitis, medications available for the treatment of rhinitis, and special circumstances (such as pregnancy or medication side-effects) that may influence a clinician's decision. Considering the economic impact of rhinitis, the cost of prescription medications, and quality-of-life issues that are affected by rhinitis, physicians dealing with managed care organizations should make their diagnosis and treatment decisions carefully.

Nasal secretion analysis in allergic rhinitis, cystic fibrosis, and nonallergic fibromyalgia/chronic fatigue syndrome subjects

Rhinitis symptoms are present in approximately 70% of subjects with fibromyalgia and chronic fatigue syndrome (FM/CFS). Because only 35% to 50% have positive allergy skin tests, nonallergic mechanisms may also play a role. To better understand the mechanisms of nonallergic rhinitis in FM/CFS, nasal lavages were performed, and markers of vascular permeability, glandular secretion, and neutrophil and eosinophil infiltration measured in 27 nonallergic FM/CFS, 7 allergic rhinitis, 7 cystic fibrosis, and 9 normal subjects. Allergic rhinitis subjects had significantly increased vascular permeability (IgG) and ECP levels. Cystic fibrosis subjects had significantly higher elastase and total protein levels. There were no significant differences between FM/CFS and normal lavage fluids. Analysis of the constituents of nasal mucus provides information about ongoing secretory processes in rhinitis. There were no differences in the basal secretion of these markers of vascular permeability, submucosal gland serous cell secretion, eosinophil and neutrophil degranulation in nonallergic FM/CFS subjects. This suggests that constitutively active secretory processes that regulate continuous production of nasal secretions are not altered in FM/CFS. Future studies should examine alternative mechanisms such as inducible, irritant-activated, or reflex-mediated effects.

Intranasal salmeterol inhibits allergen-induced vascular permeability but not mast cell activation or cellular infiltration

BACKGROUND

Salmeterol is a long-acting beta2-adrenergic agonist that is widely used in the treatment of asthma. It has been suggested that non-bronchodilator actions of salmeterol may contribute to its efficacy.

OBJECTIVE

To further evaluate the potential non-bronchodilator actions of salmeterol in vivo, using a model of nasal challenge with allergen.

METHODS

Twelve asymptomatic subjects with seasonal allergic rhinitis participated in a randomized, double-blind, placebo-controlled crossover trial of the effects of a single dose of 100 microg of salmeterol on the response to allergen challenge. Sneezing and symptom scores, and levels of histamine and albumin in nasal lavages, were measured throughout the protocol. Concentrations of tryptase, prostaglandin D2 and lysozyme were measured during the acute allergic response, while levels of IL-3, IL-5 and IL-8 were measured at later time points. Numbers of eosinophils and of total white blood cells were also recorded.

RESULTS

Salmeterol did not affect sneezing or symptom scores at any point. During the immediate response to allergen challenge, mast cell activation, reflected by concentrations of histamine, tryptase and prostaglandin D2, and serous glandular secretion, assessed by measurements of lysozyme, were unaffected by salmeterol treatment but vascular permeability, reflected by concentrations of albumin in nasal lavages, was significantly reduced. At later time points, salmeterol had no effect on levels of histamine or albumin and did not affect cellular infiltration. Concentrations of IL-3, IL-5 and IL-8 were not increased by allergen challenge in these subjects, so the effects of salmeterol could not be evaluated.

CONCLUSIONS

Treatment with a single dose of salmeterol had no effect on activation of mast cells or cellular infiltration but inhibited vascular permeability. The ability of salmeterol to inhibit antigen-induced vascular permeability may contribute to its therapeutic efficacy in asthma.

RANTES induces nasal mucosal inflammation rich in eosinophils, basophils, and lymphocytes in vivo

RANTES is a CC chemokine that causes chemotaxis of eosinophils, basophils, and lymphocytes in vitro. The objective of this study was to investigate the effect of RANTES on the influx of inflammatory cells into the nasal mucosa of 12 allergic patients. In the first phase, each patient was challenged with RANTES or diluent on two subsequent days. RANTES caused a significant (p < 0.05) influx of eosinophils as compared with the diluent. The number of eosinophils were 5,548 +/- 1,532/ml and 462 +/- 206/ml after RANTES and diluent challenge, respectively, at the peak of the response at 2 h. There was also a significant influx of metachromatic cells and lymphocytes, but not monocytes, neutrophils, or epithelial cells after RANTES challenge. In the second phase, the patients were first challenged with an allergen and 24 h later, challenged with RANTES or diluent. In the allergen-primed mucosa RANTES induced a significantly higher influx of eosinophils, basophils, and lymphocytes. Further, RANTES caused migration of monocytes and neutrophils, and shedding of epithelial cells. The influx of the inflammatory cells was associated with symptoms of rhinitis. We conclude that RANTES induces a clinically symptomatic inflammatory response in vivo by causing chemotaxis of eosinophils, basophils, and mononuclear cells.