The time course of the bilateral release of cytokines and mediators after unilateral nasal allergen challenge

The Impact of Cytokines on Health-Related Quality of Life in Adolescents with Allergic Rhinitis

BACKGROUND

Frequent episodes of nasal symptoms are the usual clinical manifestations (CM) of allergic rhinitis (AR) and have a significant negative impact on health-related quality of life (HRQoL) in adolescents. The purpose of this cross-sectional study was to test the hypothesis that cytokines in nasal mucus may be associated with HRQoL in adolescents with AR.

METHODS

European Quality of Life 5 Dimensions 3 Level Version (EQ-5D-3L), "The Adolescent Rhinoconjunctivitis Quality of Life Questionnaire" (AdolRQLQ) and the Total 4 Symptom Score (T4SS) scoring system were administered to 113 adolescents with AR, nonallergic rhinitis (NAR) and to healthy control subjects. Nasal secretions were sampled and tested for 13 cytokines using a multiplex flow cytometric bead assay.

RESULTS

The AR group had significantly lower EQ-5D-3L (0.661 ± 0.267 vs. 0.943 ± 0.088; p < 0.001) and higher AdolRQLQ total scores (2.76 ± 1.01 vs. 1.02 ± 0.10; p < 0.001) compared to the control group. The AR group had higher concentrations of IL-1β (p = 0.002), IL-6 (p = 0.031), IL-8 (p < 0.001), IL17-A (p = 0.013) and IL-18 (p = 0.014) compared to the control group, and IL-1β, IL-6, IL17-A and IL-18 were significantly (p < 0.050) increased with disease progression. Cytokines IL-1β, IL-6, as well as severe CM, were identified as significant predictors of lower HRQoL in adolescents with AR.

CONCLUSIONS

This study identified IL-1β, IL-6, as well as severe CM, as predictors of lower HRQoL in adolescents with AR. However, these results should only serve as a starting point for additional confirmation research.

A Novel Bionebulizer Approach to Study the Effects of Natural Mineral Water on a 3D In Vitro Nasal Model from Allergic Rhinitis Patients

Sulfurous thermal waters (STWs) are used as a complementary treatment for allergic rhinitis. However, there is scant data on the effects of STW on nasal epithelial cells, and in vitro models are warranted. The main aim of this study was to evaluate the dose and time effects of exposure to 3D nasal inserts (MucilAirTM-HF allergic rhinitis model) with STW or isotonic sodium chloride solution (ISCS) aerosols. Transepithelial electrical resistance (TEER) and histology were assessed before and after nebulizations. Chemokine/cytokine levels in the basal supernatants were assessed by enzyme-linked immunosorbent assay. The results showed that more than four daily nebulizations of four or more minutes compromised the normal epithelial integrity. In contrast, 1 or 2 min of STW or ISCS nebulizations had no toxic effect up to 3 days. No statistically significant changes in release of inflammatory chemokines MCP-1/CCL2 > IL-8/CXCL8 > MIP-1α/CCL3, no meaningful release of "alarmins" (IL-1α, IL-33), nor of anti-inflammatory IL-10 cytokine were observed. We have characterized safe time and dose conditions for aerosol nebulizations using a novel in vitro 3D nasal epithelium model of allergic rhinitis patients. This may be a suitable in vitro setup to mimic in vivo treatments of chronic rhinitis with STW upon triggering an inflammatory stimulus in the future.

IL-1β and Allergy: Focusing on Its Role in Allergic Rhinitis

Allergic rhinitis (AR) is a chronic upper airway immune-inflammation response mediated by immunoglobulin E (IgE) to allergens and can seriously affect the quality of life and work efficiency. Previous studies have shown that interleukin-1β (IL-1β) acts as a key cytokine to participate in and promote the occurrence and development of allergic diseases. It has been proposed that IL-1β may be a potential biomarker of AR. However, its definitive role and potential mechanism in AR have not been fully elucidated, and the clinical sample collection and detection methods were inconsistent among different studies, which have limited the use of IL-1β as a clinical diagnosis and treatment marker for AR. This article systematically summarizes the research advances in the roles of IL-1β in allergic diseases, focusing on the changes of IL-1β in AR and the possible interventions. In addition, based on the findings by our team, we provided new insights into the use of IL-1β in AR diagnosis and treatment, in an attempt to further promote the clinical application of IL-1β in AR and other allergic diseases.

An integrated cytokine and kynurenine network as the basis of neuroimmune communication

Two of the molecular families closely associated with mediating communication between the brain and immune system are cytokines and the kynurenine metabolites of tryptophan. Both groups regulate neuron and glial activity in the central nervous system (CNS) and leukocyte function in the immune system, although neither group alone completely explains neuroimmune function, disease occurrence or severity. This essay suggests that the two families perform complementary functions generating an integrated network. The kynurenine pathway determines overall neuronal excitability and plasticity by modulating glutamate receptors and GPR35 activity across the CNS, and regulates general features of immune cell status, surveillance and tolerance which often involves the Aryl Hydrocarbon Receptor (AHR). Equally, cytokines and chemokines define and regulate specific populations of neurons, glia or immune system leukocytes, generating more specific responses within restricted CNS regions or leukocyte populations. In addition, as there is a much larger variety of these compounds, their homing properties enable the superimposition of dynamic variations of cell activity upon local, spatially limited, cell populations. This would in principle allow the targeting of potential treatments to restricted regions of the CNS. The proposed synergistic interface of 'tonic' kynurenine pathway affecting baseline activity and the superimposed 'phasic' cytokine system would constitute an integrated network explaining some features of neuroimmune communication. The concept would broaden the scope for the development of new treatments for disorders involving both the CNS and immune systems, with safer and more effective agents targeted to specific CNS regions.

IL-1β promotes immunoregulatory responses in human blood basophils

Human basophils are essential effector cells of chronic allergic inflammation. IL-1 family cytokines such as interleukin (IL)-33 and IL-1β are elevated in serum and bronchoalveolar lavage fluid of allergic asthmatics. IL-33 is known to be a critical regulator of basophil's T2 immune responses. However, the effect of IL-1β on the function of basophils has not been well investigated. Here, we elucidate whether IL-1β regulates the function of human basophils and compared the effects of IL-1β and IL-33 on basophils of healthy and allergic subjects. We found that IL-1β activates the p38 MAPK signaling pathway and promotes IL-8 release in basophils of healthy donors, while FcεRI-mediated LCT₄ and histamine secretion is not affected. Strikingly, in the presence of IL-3, IL-1β shows more potency than IL-33, as evidenced by the enhanced p38 phosphorylation and NF-κB activation, as well as the release of both IL-13 and IL-8. We found that the enhanced basophil responsiveness is achieved through IL-3-induced IL-1RI surface expression. Importantly, basophils of allergic donors release significantly higher amounts of IL-8 compared to those from healthy donors upon IL-33 and IL-1β stimulation. Consistently, we detected increased IL-1RI and decreased IL-3 receptor alpha-chain (CD123) and CCR3 expression on basophils of allergic subjects compared to healthy controls, suggesting an in vivo IL-3 priming in allergic donors. In summary, our results suggest enhanced sensitivity of basophils toward IL-33 and IL-1β in allergic subjects compared to those from healthy controls.

Precision medicine reaching out to the patients in allergology - a German-Japanese workshop report

An expert workshop in collaboration of the German Society of Allergy and Clinical Immunology (DGAKI) and the Japanese Society of Allergy (JSA) provided a platform for key opinion leaders of both countries aimed to join expertise and to highlight current developments and achievements in allergy research. Key domains of the meeting included the following seven main sections and related subchapters: 1) basic immunology, 2) bronchial asthma, 3) prevention of allergic diseases, 4) food allergy and anaphylaxis, 5) atopic dermatitis, 6) venom allergy, and 7) upper airway diseases. This report provides a summary of panel discussions of all seven domains and highlights unmet needs and project possibilities of enhanced collaborations of scientific projects.

Quartz Dust Exposure Affects NLRP3 Inflammasome Activation and Plasma Levels of IL-18 and IL-1Ra in Iron Foundry Workers

Purpose

To study the association between inhalation of particulate matter or quartz in Swedish iron foundries and the effects on NLRP3 inflammasome activation.

Methods

Particle exposure measurements were performed during an eight-hour work day for 85 foundry workers at three Swedish iron foundries. Personal sampling was used for measurement of respirable quartz and dust and stationary measurements to obtain exposure measurements for inhalable dust and PM₁₀. The NLRP3 inflammasome markers, interleukin- (IL-) 1β and IL-18, and inhibitors IL-1 receptor antagonist (IL-1Ra) and IL-18 binding protein (IL-18BP) were measured in plasma. Inflammasome activation was measured by caspase-1 enzymatic activity in monocytes in whole blood by flow cytometry, and expression of inflammasome-related genes was quantified using real-time PCR. Multiple linear regression analysis was used to investigate associations between PM exposures and inflammatory markers. Sex, age, smoking, current infection, BMI, and single nucleotide polymorphism in the inflammasome regulating genes CARD8 (C10X) and NLRP3 (Q705K) were included as covariates.

Results

The average exposure levels of respirable dust and quartz were 0.85 and 0.052 mg/m³, respectively. A significant exposure-response was found for respirable dust and IL-18 and for inhalable dust and IL-1Ra. Whole blood, drawn from study participants, was stimulated ex vivo with inflammasome priming stimuli LPS or Pam3CSK4, resulting in a 47% and 49% increase in caspase-1 enzymatic activity in monocytes. This increase in caspase-1 activity was significantly attenuated in the higher exposure groups for most PM exposure measures.

Conclusions

The results indicate that exposure levels of PM in the iron foundry environment can affect the NLRP3 inflammasome and systemic inflammation.

[Nasal provocation with increased ASA dose: improved "non-steroidal anti-inflammatory drugs (NSAIDs)-exacerbated disease" (N‑ERD) detection rate in chronic rhinosinusitis patients]

BACKGROUND

Analgesic intolerance (AI) is an important diagnostic feature of disease progression in patients with chronic rhinosinusitis (CRS) accompanied by nasal polyps (CRSwNP) and asthma.

OBJECTIVE

The aim of the present study was to determine whether increasing the concentration of acetylsalicylic acid (ASA) used in the diagnostic nasal challenge would improve detection of ASA intolerance (NSAIDs-exacerbated respiratory disease, N‑ERD).

METHODS

Patients with CRSwNP, asthma, and with (CRSwNP-AAI, n = 20) or without (CRSwNP-A, n = 15) anamnestically reported AI, as well as control subjects with CRS but no nasal polyps, asthma, or AI (n = 15), were challenged nasally with 16 mg ASA and, in case of a negative result, with 25 mg of ASA.

RESULTS

In CRSwNP-AAI subjects, the challenge with 16 mg ASA resulted in detection of AI in 80% of cases; increasing the challenge of ASA to 25 mg improved the AI detection to 95%. In CRSwNP-A subjects, the detection of AI increased from 40% (16 mg ASA) to 53% (25 mg ASA). In the control group, no reaction to nasal ASA challenge was detected. No difference in the diagnosis of positive reactions after provocation was found when using the German vs. the European recommended evaluation criteria. Mild pulmonary symptoms occurred in 2 (10%) CRSwNP-AAI patients following the 16 mg ASA challenge.

CONCLUSION

In patients with CRSwNP, asthma, and anamnestic AI, nasal provocation can effectively confirm the diagnosis of N‑ERD and can also be recommended for patients with recurrent CRSwNP and asthma but without reported AI. Increasing the ASA challenge to 25 mg increases the overall detection rate.

Association between allergic and nonallergic rhinitis and obstructive sleep apnea

PURPOSE OF REVIEW

Allergic rhinitis and nonallergic rhinitis (NAR) are common disorders, which have been considered as potential risk factors for obstructive sleep apnea (OSA). This review summarizes the proposed underlying pathophysiological mechanisms to provide a better understanding of the relationship between these conditions.

RECENT FINDINGS

In adults, allergic rhinitis and NAR may be considered as symptoms potentiating, rather than risk potentiating factors in the pathophysiology of OSA, whereas in children, these are considered to be independent predictors for sleep-disordered breathing (SDB) and failure of adeno-tonsillectomy, the recommended first-line therapy for children with OSA. Current advances suggest IL-6 may be important in regulating the sleep-wake cycle, and serum soluble IL-6 receptor (sIL-6R) levels may reflect the severity of OSA. Elevated Th17/Treg ratio correlates positively with apnea-hypopnea index of OSA patients, and Th17 and Treg imbalances caused by allergic rhinitis and OSA, respectively, may possibly promote each other, leading to further imbalance. Moreover, obesity is a strong risk factor for OSA, and leptin plays an important role in ventilatory function and upper airway obstruction. The variant trigeminocardiac reflex and nasotrigeminal reflex may also be involved in the association between rhinitis and OSA.

SUMMARY

Allergic rhinitis/NAR and OSA are closely associated, and each condition can be detrimental to the other. Thus, clinicians should pay attention to the potential presence of allergic rhinitis/NAR in OSA patients and vice versa.

A novel nasal almotriptan loaded solid lipid nanoparticles in mucoadhesive in situ gel formulation for brain targeting: Preparation, characterization and in vivo evaluation

This work aimed at designing efficient safe delivery system for intranasal (IN) brain targeting of the water soluble anti- migraine drug Almotriptan malate (ALM). Solid lipid nanoparticles (SLNs) were prepared by w/o/w double emulsion-solvent evaporation method. Selection of the optimized SLNs formula was based on evaluating particle size (PS), poly dispersity index (PDI) and entrapment efficiency (%EE). Optimized formula exhibited acceptable ranges; PS of 207.9 nm, PDI of 0.41 and %EE of 50.81%. Poloxamer 407 (Plx) at different concentrations (16%, 18%, 20% w/v), with different mucoadhesive polymers (Carbopol-974P, Na alginate, Na-CMC) were evaluated for gelling time and temperature, pH and mucoadhesion. The chosen mucoadhesive in-situ gel formula; 18% Plx 407 based-0.75%w/v Na-CMC, showed acceptable results, so that the optimized SLNs formula was further dispersed in it and evaluated for in vitro release, stability, in vivo and pharmacokinetics studies. Biomarkers' evaluation and histopathological examination were also investigated. Results revealed rapid ALM brain delivery of the optimized formula; Brain/blood ratios at 10 min. for NF (SLNs based IN in-situ gel), ND (Free ALM IN in situ gel) and ALM i.v. (ALM IV solution) were 0.89, 0.19 and 0.31, respectively. Toxicological results confirmed the safety of NF for nasal administration. The achieved out comings are encouraging for further clinical trials of the developed system in humans in future research.

Absorption of Nasal and Bronchial Fluids: Precision Sampling of the Human Respiratory Mucosa and Laboratory Processing of Samples

The methods of nasal absorption (NA) and bronchial absorption (BA) use synthetic absorptive matrices (SAM) to absorb the mucosal lining fluid (MLF) of the human respiratory tract. NA is a non-invasive technique which absorbs fluid from the inferior turbinate, and causes minimal discomfort. NA has yielded reproducible results with the ability to frequently repeat sampling of the upper airway.

By comparison, alternative methods of sampling the respiratory mucosa, such as nasopharyngeal aspiration (NPA) and conventional swabbing, are more invasive and may result in greater data variability. Other methods have limitations, for instance, biopsies and bronchial procedures are invasive, sputum contains many dead and dying cells and requires liquefaction, exhaled breath condensate (EBC) contains water and saliva, and lavage samples are dilute and variable.

BA can be performed through the working channel of a bronchoscope in clinic. Sampling is well tolerated and can be conducted at multiple sites in the airway. BA results in MLF samples being less dilute than bronchoalveolar lavage (BAL) samples.

This article demonstrates the techniques of NA and BA, as well as the laboratory processing of the resulting samples, which can be tailored to the desired downstream biomarker being measured. These absorption techniques are useful alternatives to the conventional sampling techniques used in clinical respiratory research.

[Local allergic rhinitis to Alternaria alternata : Evidence for local IgE production exclusively in the nasal mucosa]

In a subgroup of patients with symptoms of allergic rhinitis (AR), no systemic sensitization can be detected in skin tests or serum. These patients are considered to be afflicted with so-called "local allergic rhinitis" (LAR) with IgE-production exclusively at the site of the nasal mucosa. Patients without any positive allergy test results but seasonal (intermittent) or perennial (persistent) allergic symptoms were often misdiagnosed as having "non-allergic rhinitis" (NAR) in the past.However, there is evidence for a specific IgE-production in the nasal mucosa in these patients without systemic sensitization. The diagnosis of LAR is confirmed by clinical symptoms, the detection of specific IgE production in the nasal mucosa and/or nasal provocation tests.We report on two cases of LAR to Alternaria alternata with symptoms of persistent allergic rhinitis that have been diagnosed by positive allergenspecific nasal challenge tests and specific IgE determinations in nasal secretions.According to an actual literature research, this is the second report published on LAR caused by Alternaria alternata.

Establishment of a new animal model of allergic rhinitis with biphasic sneezing by intranasal sensitization with Staphylococcal enterotoxin B

Allergic rhinitis (AR) is a global health problem. The effectiveness of currently available medications is limited and therefore investigation for more effective drugs is essential. The aim of the present study was to establish a model of AR in guinea pigs that can be utilized for the further investigation of new drugs. Guinea pigs were intranasally sensitized with 1 µg Staphylococcal enterotoxin B (SEB) dissolved in 40 µl saline once daily for 14 days. One week after the last sensitization, the same treatment was applied intranasally once every four days for a total of 30 times. In the treatment group, terfenadine was administered orally 70 min before the 4th, 14th and 24th challenge. Sneezing and nasal scratching were evaluated following each of the 30 challenges. The quantity of antigen-specific antibodies in the serum was measured. Between the 19th and 30th challenges, the guinea pigs in the model group produced significant biphasic elevations in sneezing number, with peaks 10 min-2 h and 4-8 h after the SEB challenges. In addition, the guinea pigs produced significantly more sneezing in the first peak during the 19th to 30th challenges than during the first to 18th challenges (P<0.01). Terfenadine significantly inhibited the early- and late-phase sneezing at all challenge times. The serum levels of SEB-specific immunoglobulin (Ig) E and IgG₁ were higher in the model group in comparison with those in the control group (P<0.01). This experiment demonstrated that SEB can induce typical AR with biphasic sneezing in guinea pigs. Histamine may play an important role in the early- and the late-phase sneezing in the model of AR. This model can be potentially used for the investigation of new drugs.

In Vivo Anti-Inflammatory Effect of H1 Antihistamines in Allergic Rhinitis: A Randomized Clinical Trial

BACKGROUND

Allergic rhinitis is characterized by a chronic inflammation of nasal mucosa and represents a risk factor for asthma occurrence. H1 antihistamines reduce the symptoms of rhinitis, but some compounds may have anti-inflammatory properties.

AIMS

We evaluated the plasma level of some cytokines in patients with persistent allergic rhinitis (PAR) and their evolution after a 4-week treatment with H1 anti-histamines, as well as the risk of asthma after 1.5 years.

STUDY DESIGN

Randomized clinical trial.

METHODS

Eighty-five patients with PAR and 30 healthy volunteers were included in the study. The patients with PAR were randomly divided into 2 groups: 41 patients treated with 5 mg/day desloratadine and 44 patients under 5 mg/day levocetirizine for 4 weeks. The clinical and biological evaluations were performed before and after treatment and included rhinitis symptoms and total symptoms score, type of sensitization, and plasmatic levels of total IgE, IL-1β, IL-6, IL-8 and TNF-α.

RESULTS

IL-8 and TNF-α were significantly increased in patients with PAR compared to healthy volunteers (5.85 vs 3.12, p<0.001 and 2.32 vs 1.06, p<0.001, respectively). Both H1 antihistamines reduce all symptoms of allergic rhinitis, including nasal congestion and the plasmatic level of IL-1β, IL-6, IL-8 and TNF-α, after 4 weeks of treatment. The reduction of cytokine levels was not influenced by patients' age, sex, duration or severity of rhinitis, or type of sensitization. Levocetirizine has a superior effect compared to desloratadine in reducing the rhinitis symptoms and cytokines' level. Twenty eight (32.9%) of the patients presented asthma symptoms after 1.5 years. The occurrence of asthma was influenced by house dust sensitization (OR-14.6; CI 95% 1.8-116.3; p=0.01), but baseline values of cytokines were not predictive factors for its appearance.

CONCLUSION

Levocetirizine and desloratadine as a prolonged therapy reduce plasmatic levels of some pro-inflammatory cytokines in patients with PAR. Levocetirizine has a better effect on decreasing the symptoms and plasmatic levels of IL-1β and IL-8. (ClinicalTrials. gov Identifier: NCT02507635).

FOUNDING

POSDRU and University of Medicine and Pharmacy, Iuliu Haţieganu, Cluj Napoca.

Effect of grass pollen immunotherapy on clinical and local immune response to nasal allergen challenge

Rationale

Nasal allergen provocations may be useful in investigating the pathophysiology of allergic rhinitis and effects of treatments.

Objective

To use grass pollen nasal allergen challenge (NAC) to investigate the effects of allergen immunotherapy in a cross‐sectional study.

Methods

We studied nasal and cutaneous responses in untreated subjects with seasonal grass‐pollen allergic rhinitis (n = 14) compared with immunotherapy‐treated allergics (n = 14), plus a nonatopic control group (n = 14). Volunteers underwent a standardized NAC with 2000 biological units of timothy grass allergen (equivalent to 1.3 μg major allergen, Phl p5). Nasal fluid was collected and analysed by ImmunoCAP and multiplex assays. Clinical response was assessed by symptom scores and peak nasal inspiratory flow (PNIF). Cutaneous response was measured by intradermal allergen injection. Retrospective seasonal symptom questionnaires were also completed.

Results

Immunotherapy‐treated patients had lower symptom scores (P = 0.04) and higher PNIF (P = 0.02) after challenge than untreated allergics. They had reduced early (P = 0.0007) and late (P < 0.0001) skin responses, and lower retrospective seasonal symptom scores (P < 0.0001). Compared to untreated allergics, immunotherapy‐treated patients had reduced nasal fluid concentrations of IL‐4, IL‐9 and eotaxin (all P < 0.05, 8 h level and/or area under the curve comparison), and trends for reduced IL‐13 (P = 0.07, area under the curve) and early‐phase tryptase levels (P = 0.06).

Conclusions

Nasal allergen challenge is sensitive in the detection of clinical and biological effects of allergen immunotherapy and may be a useful surrogate marker of treatment efficacy in future studies.

The Allergic Rhinitis - Clinical Investigator Collaborative (AR-CIC): nasal allergen challenge protocol optimization for studying AR pathophysiology and evaluating novel therapies

Background

The Nasal Allergen Challenge (NAC) model allows the study of Allergic Rhinitis (AR) pathophysiology and the proof of concept of novel therapies. The Allergic Rhinitis – Clinical Investigator Collaborative (AR-CIC) aims to optimize the protocol, ensuring reliability and repeatability of symptoms to better evaluate the therapies under investigation.

Methods

20 AR participants were challenged, with 4-fold increments of their respective allergens every 15 minutes, to determine the qualifying allergen concentration (QAC) at which the Total Nasal Symptom Score (TNSS) of ≥10/12 OR a Peak Nasal Inspiratory Flow (PNIF) reduction of ≥50% from baseline was achieved. At the NAC visit, the QAC was used in a single challenge and TNSS and PNIF were recorded at baseline, 15 minutes, 30 minutes, 1 hour, and hourly up to 12 hours. 10 additional ragweed allergic participants were qualified at TNSS of ≥8/12 AND ≥50% PNIF reduction; the Cumulative Allergen Challenge (CAC) of all incremental doses was used during the NAC visit. 4 non-allergic participants were challenged with the highest allergen concentration.

Results

In the QAC study, a group qualified by only meeting PNIF criteria achieved lower TNSS than those achieving either TNSS criteria or PNIIF+TNSS (p<0.01). During the NAC visit, participants in both studies reached their peak symptoms at 15minutes followed by a gradual decline, significantly different from non-allergic participants. The “PNIF only” group experienced significantly lower TNSS than the other groups during NAC visit. QAC and CAC participants did not reach the same peak TNSS during NAC that was achieved at screening. QAC participants qualifying based on TNSS or TNSS+PNIF managed to maintain PNIF scores.

Conclusions

Participants experienced reliable symptoms of AR in both studies, using both TNSS and PNIF reduction as part of the qualifying criteria proved better for qualifying participants at screening. Phenotyping based on pattern of symptoms experienced is possible and allows the study of AR pathophysiology and can be applied in evaluation of efficacy of a novel medication. The AR-CIC aims to continue to improve the model and employ it in phase 2 and 3 clinical trials.

Effector cell signature in peripheral blood following nasal allergen challenge in grass pollen allergic individuals

BACKGROUND

Several studies have demonstrated the time course of inflammatory mediators in nasal fluids following nasal allergen challenge (NAC), whereas the effects of NAC on cells in the periphery are unknown. We examined the time course of effector cell markers (for basophils, dendritic cells and T cells) in peripheral blood after nasal grass pollen allergen challenge.

METHODS

Twelve participants with seasonal allergic rhinitis underwent a control (diluent) challenge followed by NAC after an interval of 14 days. Nasal symptoms and peak nasal inspiratory flow (PNIF) were recorded along with peripheral basophil, T-cell and dendritic cell responses (flow cytometry), T-cell proliferative responses (thymidine incorporation), and cytokine expression (FluoroSpot assay).

RESULTS

Robust increases in nasal symptoms and decreases in PNIF were observed during the early (0-1 h) response and modest significant changes during the late (1-24 h) response. Sequential peaks in peripheral blood basophil activation markers were observed (CD107a at 3 h, CD63 at 6 h, and CD203c(bright) at 24 h). T effector/memory cells (CD4(+) CD25(lo) ) were increased at 6 h and accompanied by increases in CD80(+) and CD86(+) plasmacytoid dendritic cells (pDCs). Ex vivo grass antigen-driven T-cell proliferative responses and the frequency of IL-4(+) CD4(+) T cells were significantly increased at 6 h after NAC when compared to the control day.

CONCLUSION

Basophil, T-cell, and dendritic cell activation increased the frequency of allergen-driven IL-4(+) CD4(+) T cells, and T-cell proliferative responses are detectable in the periphery after NAC. These data confirm systemic cellular activation following a local nasal provocation.

Cytokine profiles in allergic rhinitis

Allergic rhinitis, particularly seasonal allergic rhinitis, is considered a classic Th2-mediated disease, with important contributions to pathology by interleukins 4, 5 and 13. As such, allergic rhinitis is an excellent model for studying allergic inflammation, with findings potentially relevant to the mechanism of lower airways inflammation seen in allergic asthma. However, recent evidence has revealed roles for additional non-Th2 cytokines in asthma, including IL-17 family cytokines and epithelial-derived cytokines. Additionally, putative roles for epithelial-derived cytokines and innate lymphoid cells have been described in chronic rhinosinusitis with nasal polyps. Here, evidence for the involvement of different cytokines and cytokine groups in allergic rhinitis is considered.

Fluticasone furoate inhibits cytokine secretion from nasal epithelial cells and reduces eosinophil survival in an in vitro model of eosinophilic inflammation

BACKGROUND

Fluticasone furoate (FF) is an intranasal corticosteroid indicated for the treatment of allergic rhinitis (AR). However, the anti-inflammatory effects of FF in the nasal mucosa have yet to be investigated thoroughly. The aim of this study was to investigate the effect of FF on eosinophil survival and cytokine secretion from nasal mucosa epithelial cells.

METHODS

Epithelial cells obtained from nasal mucosa were stimulated with 10% fetal bovine serum (FBS) in the presence of FF (from 10(-12) to 10(-7)M) for 6-24 h. Cytokine [granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin (IL)-6 and IL-8] concentrations in supernatants were measured by ELISA. Peripheral blood eosinophils were incubated for 4 days with epithelial cell secretions in the presence or absence of FF (from 10(-12) to 10(-7)M) and survival was assessed by Trypan blue dye exclusion. Results are expressed as medians of the minimum effective concentration and IC values.

RESULTS

FBS stimulated the secretion of GM-CSF, IL-6 and IL-8. FF significantly inhibited GM-CSF (up to 10(-10)M, IC25 = 12.6 pM), IL-6 (up to 10(-10)M, IC25 = 65.8 pM) and IL-8 (up to 10(-11)M, IC25 = 8.6 pM) secretion induced by FBS (n = 8). Epithelial cell secretions induced eosinophil survival from day 1 to day 4 (n = 6). This effect was significantly inhibited by FF (up to 10(-12)M) at day 3 (IC50 = 3.22 nM) and day 4 (IC50 = 1.29 nM).

CONCLUSIONS

The results obtained in this in vitro model suggest that FF may reduce upper airway eosinophilic inflammation through decreasing cytokine secretion from epithelial cells and reducing eosinophil survival.

Comparison of the nasal release of IL-4, IL-10, IL-17, CCL13/MCP-4, and CCL26/eotaxin-3 in allergic rhinitis during season and after allergen challenge

BACKGROUND

Allergic rhinitis is an inflammatory disease characterized by local overproduction of type 2 cytokines and tissue eosinophilia. Recent research suggests the involvement of additional cytokines such as IL-17, chemokine (C-C motif) ligand (CCL) 26/eotaxin-3, and CCL13/monocyte chemoattractant protein-4 (MCP-4) in its pathophysiology. Furthermore, bronchial epithelial cells treated with IL-17 and type 2 cytokines distinctively up-regulated eotaxin-3 gene expression. In this study we investigated the kinetics of IL-4, IL-10, IL-17, eotaxin-3, and MCP-4 in seasonal allergic rhinitis volunteers after nasal allergen challenge (NAC) and their release during natural pollen exposure.

METHODS

The nasal lavages of 15 symptomatic allergic and 14 nonallergic subjects were collected during the pollination season. Additionally, six allergic subjects underwent a single unilateral nasal allergen and control challenge out of season, and nasal secretions were collected. Levels of IL-4, IL-10, IL-17, eotaxin-3, and MCP-4 in nasal lavages and secretions were measured using an electrochemiluminescent assay.

RESULTS

After NAC, allergic subjects had a significant immediate response of nasal symptoms as well as a significant increase at 5 hours of IL-4, IL-10, and IL-17 and at 2, 5, and 24 hours significantly raising levels of eotaxin-3. IL-17 and eotaxin-3 concentrations at 5 hours were correlated (r = 0.94; p = 0.005). During natural pollen exposure, barely detectable levels of IL-17 in allergic subjects were also correlated with eotaxin-3 (r = 0.62; p = 0.01). Eotaxin-3 and MCP-4 levels were significantly elevated 9- or 3.7-fold, respectively, and IL-10 and, unexpectedly, IL-4 were significantly lower in allergic subjects compared with nonallergic subjects.

CONCLUSION

Nasal IL-17, MCP-4, and, possibly, eotaxin-3 may aggravate and IL-10 may alleviate nasal mucosal allergy.

[Local (exclusive) IgE production in the nasal mucosa. Evidence for local allergic rhinitis]

BACKGROUND

IgE production at the site of the nasal mucosa without systemic allergic sensitization in skin tests or in serum represents so-called "local allergic rhinitis (LAR)" as a subgroup of patients with symptoms of allergic rhinitis (AR). Formerly, in case of negative allergological test results, seasonal (intermittent) or perennial (persistent) allergic symptoms have been diagnosed as "non-allergic rhinitis" (NAR). However, there is evidence for specific Th2 cytokine, tryptase, and ECP (eosinophil catonic protein) production in the nasal secretion after allergen exposure in these patients without systemic sensitization.

DIAGNOSIS

Taking this into account, we recommend performing an allergen-specific nasal challenge and measuring the (local) nasal IgE-levels in addition to standard allergy tests in clinical routine in this subgroup of patients. These tests should be perfomed while or shortly after allergen exposure. In addition, an update of the allergy testing should be performed after a time interval since it has been demonstrated that patients formerly diagnosed with NAR may develop LAR or AR, or patients with LAR may develop AR in the future.

TREATMENT

The pharmacological therapeutic options in LAR are in line with the treatment of AR. If and to what extent this subgroup of AR patients benefit from allergen-specific immunotherapy (SIT) is currently being evaluated in clinical trials.

Evaluation of clinical and immunological responses: a 2-year follow-up study in children with allergic rhinitis due to house dust mite

Background. Allergic rhinitis is a disease with polarization towards Th₂ and a defect of regulatory T cells. Immunological changes have been reported after immunotherapy treatment. However, there is not much known about the natural course of allergic rhinitis with respect to clinical manifestation and the relation with immunological responses. Objective. To evaluate clinical symptoms of allergic rhinitis, in relation to in vivo allergen-specific skin responses and in vitro allergen-specific effector and regulatory T cells determined at baseline and after two years. Methods. From a large trial, 59 children were randomly selected. The following variables were compared: clinical symptoms, allergen skin tests, specific IgE, T-cell proliferation, IL-5, IL-13, IFN-gamma, IL-10, TGF-beta, CD4⁺CD25^hi cells, and Foxp3 expression. Results. Allergic symptoms had decreased after two years. Whereas skin test reactions correlated between years 0 and 2, there was no change in the size of the reaction. Also, proinflammatory reactions did not change after two years, with a positive correlation between years 0 and 2. No relevant changes were observed with respect to regulatory cells. Conclusion. Whereas, comparable to immunotherapy, allergic complaints decrease, the immunological changes of specific T-cell activity (both effector cells and regulator cells) which are observed after immunotherapy, do not change.

The release of IL-31 and IL-13 after nasal allergen challenge and their relation to nasal symptoms

Background

IL-31, a recently discovered member of the gp130/IL-6 cytokine family, is mainly expressed by human mast cells and T helper type 2 cells. IL-31 is a key trigger of atopic dermatitis. Recent studies also suggest a role of IL-31 in the pathogenesis of other allergic diseases including allergic rhinitis. In the present study we studied the release of IL-31 and IL-13 in allergen-challenged allergic rhinitis patients.

Methods

Seven seasonal allergic volunteers underwent unilateral nasal provocation with allergen (and a control challenge) with the disc method out of the allergy season. Nasal symptom scores (rhinorrhea, itching, sneezing, obstruction) and bilateral nasal secretions were quantified before and after allergen provocation. IL-13 and IL-31 in nasal secretions and serum were measured by electrochemiluminescent immunoassay or ELISA, respectively.

Results

Nasal allergen challenge induced the typical clinical symptoms and physiological changes. IL-31 and IL-13 in nasal secretions increased in four and five, respectively, volunteers at 5 h after allergen but not after control challenge. We observed correlation trends between nasal IL-31 concentrations and IL-13 concentrations (r = 0.9, p = 0.002), and IL-31 contents and symptom scores (r = 0.9, p = 0.013) 5 h after allergen provocation. No IL-31 could be detected contralaterally or systemically in the sera.

Conclusions

The observed local upregulation of IL-31 mainly during the late phase reaction after nasal allergen challenge suggests a role of IL-31 in allergic rhinitis. In which way IL-31 modulates the inflammatory reaction and type 2 responses in allergic rhinitis remains to be investigated.

Immediate and dual response to nasal challenge with Dermatophagoides pteronyssinus in local allergic rhinitis

BACKGROUND

Local allergic rhinitis (LAR) is characterized by in situ production of specific IgE (sIgE) antibodies and a positive response to a nasal allergen provocation test (NAPT) in the absence of atopy.

OBJECTIVE

The aim of this study was to investigate the immunological mechanisms involved in the immediate and late responses after nasal exposure to Dermatophagoides pteronyssinus (DP) in patients with LAR.

METHODS

A total of 40 subjects with LAR to DP were studied and compared with 50 healthy controls. Immediate and late responses to NAPT-DP were assessed using a visual analogue scale of nasal symptoms and acoustic rhinometry. Tryptase, ECP, total and sIgE-DP were measured in the nasal lavage by immunoassay at baseline, 15 min, 1, 6 and 24 h after nasal challenge.

RESULTS

NAPT-DP was positive in all patients, with significant increases in tryptase (45%), ECP (65%) and sIgE-DP (25%) (P<0.05). Sixty percent of the LAR patients presented an immediate response to NAPT-DP and 40% a dual response. Immediate responders showed a fast release of tryptase with a peak at 15 min after NAPT-DP, and a progressive increase in nasal ECP and sIgE-DP from 1 to 24 h after challenge, with a peak at 24 h. Dual responders presented persistently higher levels of tryptase from 15 min to 6 h after challenge, and a similar pattern of nasal release of ECP and sIgE-DP to immediate responders. There were no isolated late responders. NAPT-DP was negative in all healthy controls, with no increases in tryptase, ECP, or total and sIgE-DP in nasal secretions.

CONCLUSIONS

The results demonstrated the existence of immediate and dual responses to a NAPT with DP in LAR patients, with the local presence of sIgE and mast cell/eosinophil activation.

Nasal inflammatory mediators and specific IgE production after nasal challenge with grass pollen in local allergic rhinitis

BACKGROUND

Evidence exists of a new form of local allergic rhinitis (LAR) with local production of specific IgE (sIgE) and a positive response to nasal allergen provocation test (NAPT) in patients previously diagnosed with idiopathic rhinitis. However, the immunologic mechanisms involved are still poorly understood.

OBJECTIVE

We explored the involvement of nasal sIgE, eosinophil, and mast cell activation in the response to NAPT with grass pollen (NAPT-grass) in a group of patients already classified with LAR.

METHODS

Out-of-spring NAPT-grass was performed in 30 patients with LAR and 30 healthy controls. Nasal symptoms, acoustic rhinometry, and nasal lavage were performed at baseline and 15 minutes and 1, 6, and 24 hours post-NAPT. Tryptase, eosinophilic cationic protein (ECP), and total and sIgE to grass pollen were measured in nasal lavage by immunoassays.

RESULTS

NAPT-grass was positive in all patients with LAR. We detected significant increases of tryptase and ECP in 40% and 43%, respectively, at 15 minutes and 1, 6, and 24 hours post-NAPT compared with baseline (P < .05). sIgE was increased in 30%, with significant increases at 1 and 6 hours (P < .05) and 24 hours (P = .002) post-NAPT. The maximum release of tryptase was detected 15 minutes after NAPT, whereas the maximum release of ECP and sIgE was detected 24 hours after challenge. NAPT-grass was negative in all healthy controls, with no increase in tryptase, ECP, total IgE, or sIgE.

CONCLUSION

These results demonstrate that patients with LAR had local production of sIgE and mast cell/eosinophil activation induced by nasal exposure to grass pollen.

Dissolution in nasal fluid, retention and anti-inflammatory activity of fluticasone furoate in human nasal tissue ex vivo

BACKGROUND

Intranasal glucocorticoids represent the most effective pharmacologic treatment of allergic rhinitis. So far, no clinical data are available that compare fluticasone furoate (FF) with other intranasally applied glucocorticoids.

OBJECTIVE

Because the pharmacokinetic behaviour of drugs governs their presence at the therapeutic target site we analysed selected in vitro properties of FF in comparison with triamcinolone acetonide (TCA), budesonide (Bud), fluticasone propionate (FP) and mometasone furoate (MF). Additionally, we determined the anti-inflammatory activity of the glucocorticoid fraction residing in human nasal tissue samples after washing.

METHODS

We analysed the solubility of the compounds in artificial human nasal fluid and the retention in human nasal tissue as well as typical spray volumes of commercially available drug preparations. As an anti-inflammatory measure, we evaluated the inhibition of IL-8 release from epithelial cells.

RESULTS

FF is delivered in the smallest application volume per spray. Despite the low aqueous solubility of glucocorticoids, a fraction of the compounds is already dissolved in the aqueous supernatants of drug preparations (Bud>TCA>FP>MF>FF). The dissolution of FP, MF and FF was significantly enhanced in artificial nasal fluid and FF displayed the most pronounced enhancement of solubility in the presence of proteins. Consistent with this result, the highest retention in nasal tissue was observed for FF, followed by FP>MF>Bud>TCA. After washing of the nasal tissue samples, all compounds inhibited IL-8 release, with FF displaying the highest activity.

CONCLUSION

FF displayed beneficial properties for nasal application. Its low application volume per spray is a prerequisite for effective drug utilization by avoiding immediate loss by nose runoff or drip down the throat. Sustained dissolution and high tissue binding of FF should contribute towards an extended presence of compounds in nasal tissue as a basis for a prolonged pharmacologic activity.

Rat nasal lavage biomarkers to assess preclinical irritation potential of nasal drug formulations and excipients

The goal of this study was to evaluate biomarkers of nasal mucosal damage for rapid assessment of irritancy potential of formulations in the rat nasal lavage model, a tool to facilitate nasal formulation development prior to histopathology studies. The nasal cavity of anesthetized rats was lavaged with normal saline 20 min pos-tdose. The collected fluid was analyzed for secreted total protein and biomarkers. Solutions tested include: normal saline, buffers, benzalkonium chloride (BAC), lysophosphatidylcholine (LPC), and four marketed nasal products. Total protein, lactate dehydrogenase and interleukin-1alpha biomarkers were secreted to varying degrees. BAC (0.2%) and LPC (0.5%) exhibiting the strongest response with a signal window ranging from 3.4- to 87-fold greater levels than normal saline. Buffer treatments, excipients, and most marketed nasal products yielded levels similar to normal saline. There was a weak correlation between formulation osmolarity and surface tension with any of the biomarkers. Each nasal formulation elicited a unique protein and biomarker profile with total protein secretion correlated with IL-1alpha secretion suggesting the potential for an inflammatory response. Taken together, rapid and potentially mechanistic information on the preclinical acute irritancy potential of formulations was assessed in the rat nasal lavage model by benchmarking treatments relative to controls and marketed nasal products.

Skin tests, T cell responses and self-reported symptoms in children with allergic rhinitis and asthma due to house dust mite allergy

BACKGROUND

In allergic responses, a distinction is made between an early-phase response, several minutes after allergen exposure, and a late-phase response after several hours. During the late phase, eosinophils and T cells infiltrate the mucosa and play an important role in inflammation.

OBJECTIVE

The aim of this study was to examine the relationship between allergen-induced late-phase skin responses and in vitro T cell reactivity. In addition, the relationship between allergen-induced skin or T cell responses and the severity of self-reported symptoms was studied in children with house dust mite allergy.

METHODS

A total of 59 house dust mite-allergic children (6-18 years) were recruited in general practice. These children or their parents rated their nasal and asthma symptoms on diary cards during 1 month. Allergen skin tests were performed and read after 15 min (early phase) and 6 h (late phase). Allergen-specific T cell proliferation was determined, and Th2 cytokine (IL-5 and IL-13) secretion was analysed.

RESULTS

The size of the late-phase skin response correlated with in vitro T cell proliferation (r(s)=0.38, P=0.003) but not with Th2 cytokine secretion (r(s)=0.16, P=0.2 for both IL-5 and IL-13). Moreover, the late-phase skin response and T cell proliferation correlated with asthma symptoms (r(s)=0.30, P=0.02 for skin response and r(s)=0.28, P=0.03 for T cell proliferation) but not with nasal symptoms (r(s)=0.19, P=0.15 for skin response and r(s)=0.09, P=0.52 for T cell proliferation). The early-phase skin response correlated with the nasal symptom score (r(s)=0.34, P=0.01) but not with asthma symptom scores (r(s)<0.005, P=0.97).

CONCLUSION

In this study, the late-phase skin test response correlated with in vitro T cell proliferation but not with Th2 cytokine secretion. We found weak or no correlations between late-phase skin responses and symptoms of asthma or rhinitis in children with house dust mite allergy. This suggests that late-phase skin responses reflect certain T cell properties but are of limited value for the evaluation of airway symptoms in atopic children.

Comparative proteomics of nasal fluid in seasonal allergic rhinitis

A comparative proteomic approach was applied to examine nasal lavage fluid (NLF) from patients with seasonal allergic rhinitis (SAR, n = 6) and healthy subjects (controls, n = 5). NLF samples were taken both before allergy (pollen) season and during season, and proteins were analyzed by two-dimensional gel electrophoresis (2-DE) and matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) after tryptic cleavage. Twenty proteins were selected and quantified. During allergy season, the levels of six sialylated isoforms of PLUNC (palate lung nasal epithelial clone) were lower in SAR patients than controls, as were the levels of six isoforms of von Ebner's gland protein (VEGP), including a previously undescribed form with N-linked glycosylation, and of cystatin S. PLUNC is a new innate immunity protein and VEGP and cystatin S are two endogenous proteinase inhibitors. By contrast, the levels of an acidic form of alpha-1-antitrypsin were higher in SAR patients than controls. One previously unidentified NLF protein was found in all samples from the SAR patients during allergy season but not in any sample before allergy season: this protein was identified as eosinophil lysophospholipase (Charcot-Leyden crystal protein/galactin 10). MS/MS analysis of the N-terminus of the protein showed removal of Met and acetylation of Ser. Altogether, these findings illustrate the potential use of proteomics for identifying protein changes associated with allergic rhinitis and for revealing post-translational modifications of such new potential markers of allergic inflammation.