Topical glucocorticoids inhibit activation by allergen in the upper respiratory tract

Modulation of Allergic Inflammation in the Nasal Mucosa of Allergic Rhinitis Sufferers With Topical Pharmaceutical Agents

Allergic rhinitis (AR) is a chronic upper respiratory disease estimated to affect between 10 and 40% of the worldwide population. The mechanisms underlying AR are highly complex and involve multiple immune cells, mediators, and cytokines. As such, the development of a single drug to treat allergic inflammation and/or symptoms is confounded by the complexity of the disease pathophysiology. Complete avoidance of allergens that trigger AR symptoms is not possible and without a cure, the available therapeutic options are typically focused on achieving symptomatic relief. Topical therapies offer many advantages over oral therapies, such as delivering greater concentrations of drugs to the receptor sites at the source of the allergic inflammation and the reduced risk of systemic side effects. This review describes the complex pathophysiology of AR and identifies the mechanism(s) of action of topical treatments including antihistamines, steroids, anticholinergics, decongestants and chromones in relation to AR pathophysiology. Following the literature review a discussion on the future therapeutic strategies for AR treatment is provided.

Scientific rationale for the use of alpha-adrenergic agonists and glucocorticoids in the therapy of pediatric stridor

Purpose. The most common pharmacological therapies used in the treatment of stridor in children are glucocorticosteroids (GC) and alpha-adrenergic (αAR) agonists. Despite the long-standing reported efficacy of these medications, there is a paucity of data relating to their actual mechanisms of action in the upper airway. Summary. There is compelling scientific evidence supporting the use of αAR-agonists and GCs in pediatric stridor. αAR signaling and GCs regulate the vasomotor tone in the upper airway mucosa. The latter translates into better airflow dynamics, as delineated by human and nonhuman upper airway physiological models. In turn, clinical trials have demonstrated that GCs and the nonselective αAR agonist, epinephrine, improve respiratory distress scores and reduce the need for further medical care in children with stridor. Future research is needed to investigate the role of selective αAR agonists and the potential synergism of GCs and αAR-signaling in the treatment of upper airway obstruction and stridor.

Microbial superantigens induce glucocorticoid receptor beta and steroid resistance in a nasal explant model

OBJECTIVE

To study the role of superantigen (SAg) in inducing glucocorticoid (GC) receptor beta and steroid resistance in an explant model of nasal tissue.

METHODS

Nasal tissue was obtained from inferior turbinates of controls and ragweed (RW)-sensitive patients. Tissue samples were incubated with SAg of staphylococcal enterotoxin B. In addition, tissue samples from RW-sensitive patients were incubated with RW allergen in the presence and absence of both SAg and dexamethasone (DEX). The expression of GC receptor beta was assessed by immunocytochemistry. The expression of interleukin (IL)-2 and IL-4 mRNA was assessed by in situ hybridization.

RESULTS

SAg induced an increase in the expression of GC receptor beta in atopic tissue and to a lesser extent in nonatopic tissue. The most significant induction of GC receptor beta was observed in response to SAg and RW in atopic tissue. Stimulation of atopic tissue with RW alone and SAg alone induced IL-4 and IL-2 mRNA, respectively. Incubation of atopic tissue with both SAg and RW induced both IL-2 and IL-4 mRNA. The increase in IL-4 mRNA expression was blunted by the addition of DEX to atopic tissue stimulated with RW alone but not to tissue stimulated by both RW and SAg.

CONCLUSION

Our results demonstrate that SAgs induce steroid resistance in atopic nasal explant tissue by up-regulating the expression of GC receptor beta. Furthermore, we have shown that the up-regulation of GC receptor beta is a local event that is associated with the coexpression of IL-2 and IL-4 mRNA.

Inflammatory patterns of allergic and nonallergic rhinitis

Rhinitis is a chronic condition of the nasal mucosa that affects a large segment of the population. The symptoms of rhinitis occur in a variety of sinonasal conditions, which may be broadly classified as allergic (seasonal or perennial) or nonallergic (infectious or a number of noninfectious etiologies) based on the presence or absence of atopy. The cytokine profile and inflammatory patterns underlying these two conditions vary because of certain differences in their pathophysiology as discussed in this review.

Fluticasone propionate aqueous nasal spray reduces inflammatory cells in unchallenged allergic nasal mucosa: effects of single allergen challenge

BACKGROUND

Topical corticosteroid therapy reduces symptoms and nasal mucosal inflammatory cells in patients with allergic rhinitis. Usually patients are advised to start their medication (1 week) before the beginning of the pollen season. The effect of pretreatment with a topical corticosteroid on unchallenged nasal mucosa is not well documented.

OBJECTIVES

The purpose of this study was to investigate, in a double-blind, placebo-controlled study, the effect of 6 weeks' pretreatment with 200 microg twice daily fluticasone propionate on nasal symptoms and inflammatory cell numbers after nasal allergen provocation in patients with seasonal allergic rhinitis.

METHODS

Nineteen patients with grass pollen-induced allergic rhinitis were treated for a 6-week period out of the grass pollen season. After completing the treatment period, patients were challenged with grass pollen. Nasal mucosal biopsy specimens were taken 5 times in every patient. In nasal mucosa changes in numbers of T cells, B cells, mast cells, eosinophils, macrophages, and Langerhans' cells were investigated.

RESULTS

After 4 weeks of treatment but before allergen provocation, significantly fewer epithelial Langerhans' cells, macrophages, mast cells, T cells, and eosinophils were found in the fluticasone propionate group compared with those found in the placebo group. In the lamina propria significantly fewer Langerhans' cells and eosinophils were found in the fluticasone propionate group. Cell influx in nasal mucosa after allergen provocation was significantly inhibited in the fluticasone propionate group compared with that in the placebo group for epithelial Langerhans' cells, mast cells, macrophages, and T cells and for lamina propria eosinophils, mast cells, Langerhans' cells, macrophages, and T cells.

CONCLUSIONS

Fluticasone propionate is effective in reducing early- and late-phase nasal symptoms. Topical corticosteroid treatment reduces inflammatory cells in unchallenged nasal mucosa.

Intranasal mometasone furoate reduces late-phase inflammation after allergen challenge

BACKGROUND

Allergen specific nasal challenge (ASNC) is an optimal model to study the pathophysiologic mechanisms sustaining allergic inflammation, particularly the adhesion molecules promoting cellular infiltration of nasal mucosa. Topical corticosteroids have been accepted as a highly effective anti-inflammatory therapy for allergic rhinitis.

OBJECTIVE

The aim of this double-blind, randomized, placebo-controlled study was the evaluation of inflammatory events, during the late-phase, after a 2-week treatment with nasal mometasone furoate (MF), 200 microg daily, or placebo, using the model of ASNC.

METHODS

A total of 42 patients with allergic rhinitis underwent nasal challenge before and after treatment. The following parameters were evaluated at baseline, and 6 hours (late-phase) after ASNC: 1) nasal symptoms (rhinorrhea, itching, sneezing, obstruction); 2) inflammatory cells (eosinophils and neutrophils); 3) eosinophil cationic protein (ECP) and tumor necrosis factor-alpha (TNF-alpha) in nasal lavage; and 4) intercellular adhesion molecule-1 expression on nasal epithelial cells.

RESULTS

MF nasal spray was associated with late-phase reductions of: 1) clinical symptoms (P < 0.03); 2) eosinophil (P < 0.004) and neutrophil (P < 0.003) infiltration; 3) ECP (P < 0.001) and TNF-alpha (P < 0.05); and 4) intercellular adhesion molecule-1 expression on nasal epithelial cells (P < 0.001).

CONCLUSIONS

The present results demonstrate that MF has a significant effect on late-phase events, reducing the cellular influx and activation.

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.

Molecular pathology of allergic disease. II: Upper airway disease

Allergic upper airway diseases such as allergic rhinitis and chronic sinusitis are an increasing problem. Although the pathogenesis remains elusive, an individual's genetic predisposition as well as exposure to the allergen are currently considered factors in their development. Clinical symptoms of sneezing, rhinorrhea, and congestion are primarily a consequence of granulocyte release of chemical mediators such as histamine, prostanoids, and leukotrienes as well as the infiltration of inflammatory cells. Observations subsequent to allergen provocation are comparable to natural exposure and as such much of our understanding of allergic responses is derived from this model. A prominence of CD4(+) T cells and eosinophils, synthesis and release of T(H)2 cytokines, and the coordinate expression of chemokines and adhesion molecules are all characteristic of the allergic response observed in rhinitis and sinusitis. Corticosteroids and immunotherapy target these inflammatory processes and have been observed to successfully reduce and shift the predominantly T(H)2 environment toward T(H)1 cytokine expression. As our understanding of the pathophysiologic features of allergic upper airway disease improves, as well as the relationship between their development and that of lower airway disease, new strategies of diagnosis and treatment will allow for more effective modulation of the allergic process and associated morbidity.

Long-term effects of corticosteroid nasal spray on nasal inflammatory cells in patients with perennial allergic rhinitis

BACKGROUND

The effect of long-term topical nasal corticosteroid therapy on nasal inflammatory cells is unclear.

OBJECTIVES

To investigate the long-term effect of fluticasone propionate aqueous nasal spray (FPANS) on nasal mucosal inflammatory cells and efficacy in a 1-year study in patients with perennial allergic rhinitis.

METHODS

In a 1-year, double-blind, placebo-controlled study of duration we investigated the influence of a topical corticosteroid (FPANS), on Langerhans' cells (CD1a+ cells), T cells, mast cells, eosinophils and macrophages in nasal mucosa in 42 patients with perennial allergic rhinitis. Efficacy was evaluated by nasal symptom score.

RESULTS

The FPANS group experienced significantly less sneezing and nasal itching compared with the placebo group. The total symptom score in the FPANS group declined significantly in comparison with baseline (P = 0.007) and placebo group (P = 0.009). After 1 year of active treatment, a significant decrease was seen in the epithelium in numbers of Langerhans' cells, CD3+, CD4+, CD8+ cells, mast cells and eosinophils. In the lamina propria, there was a significant decrease in eosinophils.

CONCLUSION

These findings show that FPANS treatment results in a decrease of nasal inflammatory cells. Furthermore, the efficacy of FPANS improves after prolonged treatment.

Effect of topical corticosteroids on seasonal increases in epithelial eosinophils and mast cells in allergic rhinitis: a comparison of nasal brush and biopsy methods

BACKGROUND

Nasal brushing and nasal biopsy are well-tolerated sampling techniques. Seasonal grass pollen-induced rhinitis is characterized by epithelial mast cell infiltration and seasonal increases in both epithelial and sub-mucosal eosinophils.

OBJECTIVE

To compare the ability of the nasal brush and nasal biopsy techniques to detect natural seasonal increases in eosinophils and mast cells, and to assess the influence of topical corticosteroid.

METHODS

Nasal brush samples and nasal biopsies were collected from 46 grass pollen-sensitive seasonal rhinitis patients before the grass pollen season and at the peak of the pollen season following 6 weeks' treatment with either fluticasone propionate aqueous nasal spray (200 microg, twice daily) or placebo nasal spray.

RESULTS

Placebo patients showed seasonal increases in epithelial eosinophils both with nasal brushing (P < 0.0001) and biopsy (P < 0.001). Epithelial mast cell numbers also increased during the pollen season as detectable by brushing (P < 0.0001) and biopsy (P < 0.03). Changes in cell numbers measured by nasal brushing correlated with those observed with nasal biopsy, both for eosinophils and mast cells (P < 0.05). Sub-mucosal eosinophils but not mast cells also increased during the pollen season (P < 0.002). Nasal brushing and biopsy revealed that fluticasone treatment inhibited seasonal increases in epithelial eosinophils (P < 0.00001) and epithelial infiltration by mast cells (nasal brushing P < 0.00001 and nasal biopsy P < 0.01). Fluticasone also inhibited seasonal increases in sub-mucosal eosinophils (P < 0.001) and significantly reduced nasal symptoms (P < 0.001).

CONCLUSION

Nasal brushing harvests sufficient inflammatory cells from the surface of the nasal mucosa to be used in lieu of nasal biopsies in observation of the effect of drugs on the nasal epithelium.

Mechanisms of intranasal steroids in the management of upper respiratory allergic diseases

Intranasal steroids have proved to be the most effective class of drugs in reducing the symptoms of allergic rhinitis. This clinical response reflects the broad anti-inflammatory activity that has been demonstrated for corticosteroids. Single doses of topical corticosteroids administered before nasal allergen challenge block the late-phase reaction, whereas repeated dosing with intranasal steroids blocks both the early and the late response, as well as the priming phenomenon. Nasal inflammation is accomplished through a number of effector cells and mechanisms, which in turn are produced by director cells through the release of cytokines and chemokines. The anti-inflammatory action of corticosteroids is largely effected through blocking the synthesis and release of these cytokines/chemokines.

Randomized placebo-controlled study comparing a leukotriene receptor antagonist and a nasal glucocorticoid in seasonal allergic rhinitis

Allergic rhinitis is an inflammatory disorder associated with local leukotriene release during periods of symptoms. Therefore, it has been suggested that antileukotrienes may be beneficial in the treatment of this disease. Leukotriene receptor antagonists have recently become available for asthma treatment, but little is known of their effects on allergic rhinitis. We have evaluated the effects of the leukotriene receptor antagonist zafirlukast versus placebo in patients with allergic rhinitis during the grass pollen season, using the nasal glucocorticoid beclomethasone dipropionate (BDP) as a positive treatment control. Thirty-three patients with seasonal allergic rhinitis were in a double-blind, double-dummy fashion randomized to treatments with oral zafirlukast (20 mg twice a day), intranasal beclomethasone dipropionate (200 microg twice a day), or placebo. The treatment was initiated 3 wk prior to the expected beginning of the grass pollen season. Patients completed a daily symptom-score list for sneezing, rhinorrhea, nasal itch, and nasal blockage during the 50-d treatment period. Nasal biopsies for quantification of local tissue eosinophilia (immunohistochemistry; EG2) were taken 1 mo before initiation of treatment and immediately after the peak of grass pollen season. Patients receiving treatment with zafirlukast had degrees of nasal symptoms similar to those in the placebo group, whereas the BDP group had significantly less symptoms compared with both treatments (p = 0.01 and p = 0.005, respectively). The numbers of activated eosinophils in the nasal tissue increased significantly during the pollen season in both the zafirlukast and the placebo groups, but not in the BDP group. These results obtained with a limited number of patients do not support any clinical efficacy of regular treatment with an oral antileukotriene in seasonal allergic rhinitis but rather favor the use of a nasal glucocorticoid.

Effect of fluticasone propionate aqueous nasal spray on allergen-induced inflammatory changes in the nasal airways of allergic rhinitics following exposure to nitrogen dioxide

BACKGROUND

The authors have recently demonstrated that prior exposure for 6 h to 400 p.p.b. nitrogen dioxide significantly enhances the early phase response of eosinophils in the nasal airways of allergic rhinitics to subsequent allergen provocation.

OBJECTIVE

To investigate whether treatment with fluticasone propionate aqueous nasal spray (FP) can alter the inflammatory response in the nasal airways under these conditions.

METHODS

Sixteen allergic, rhinitic patients were recruited for this double-blind, randomized, cross-over study and received either topical FP 200 microg once daily or matched placebo for 4 weeks. At the end of treatment, all underwent nasal lavage followed by a 6 h exposure to 400 p.p.b. NO2. Following exposure to NO2, nasal allergen challenge was performed and nasal lavage repeated. After a 4 week washout period, patients were given alternate treatment and tested as above.

RESULTS

Analysis of eosinophil cationic protein (ECP) in lavage samples from patients treated with placebo, demonstrated that this was significantly increased from a median value of 2.3 ng/mL (range: 1.0-7.1) to 15.1 ng/mL (range: 1.5-40.0; P = 0.001) following exposure to NO2 and allergen challenge. However, in patients treated with FP, ECP concentrations only increased from 3.3 ng/mL (range: 0.2-9.2) to 5.1 ng/mL (range: 0.3-20.0; P = 0.034) following exposure to NO2 and allergen challenge. The difference of the changes in ECP concentration between the placebo and the FP-treated group was significant (P = 0.003). Similarly, there was a significant increase in the number of eosinophils in nasal lavage after exposure to NO2 and allergen challenge in the placebo group, and this increase was inhibited in FP group (P = 0.002).

CONCLUSION

These results suggest that FP influences NO2- and allergen-induced changes in eosinophil function, as well as eosinophil number in the nasal airway of allergic rhinitics.

Demonstration of mast-cell chemotactic activity in nasal lavage fluid: characterization of one chemotaxin as c-kit ligand, stem cell factor

Mast cells are known to accumulate in tissue during allergic inflammation. However, the chemotaxins responsible are undefined. Using a modified Boyden chamber and the human mast-cell line HMC-1, we first identified mast-cell chemotactic activity in nasal lavage fluid collected before the pollen season after allergen provocation of allergic patients (n=29) (mean migratory response compared to medium control was 121%, range 85-198%). Mast-cell chemotactic activity was also detected in lavage fluid collected after allergen provocation at the end of a Swedish birch-pollen season from three different treatment groups: topical steroid treatment with budesonide; the topical antihistamine, levocabastine; and placebo. There was no significant difference in mast-cell chemotactic activity between nasal lavage fluid collected from the placebo group (mean=102%), the budesonide-treated group (mean=114%), or the levocabastine group (mean=125%). Stem cell factor (SCF), a known mast-cell chemotaxin, was present in the nasal lavage fluids from all three groups, and correlated with the mast-cell chemotactic activity (r=0.67, P<0.01). The mast-cell chemotactic activity was inhibited (range 5-100%) in some, but not all, nasal lavage fluids by a polyclonal antibody directed against SCF. This report describes the presence of mast-cell chemotactic activity in nasal lavage fluid during an allergic reaction. These findings show that SCF may play a pivotal role in the recruitment of mast cells in allergic rhinitis.

Risk-benefit assessment of fluticasone propionate in the treatment of asthma and allergic rhinitis

BENEFITS

Fluticasone propionate (FP) is a new topical corticosteroid spray for the treatment of allergic rhinitis and asthma. FP has been shown to be effective for the treatment of adult and pediatric asthma, even at rather low doses (25 microg twice daily [b.i.d.]); many studies in asthma have shown clinical efficacy of fluticasone at half the dose of the comparison steroid (such as beclomethasone dipropionate [BDP] or budesonide [BUD]). However, exact dose comparisons cannot be made because dose-ranging comparison studies have not been done. Studies in allergic rhinitis in children and adults have shown good efficacy in FP-treated patients at a dose of 200 microg once daily (o.d.), intranasally. In summary, FP is effective in both asthma and allergic rhinitis.

RISKS

FP has minimal systemic activity because the portion of drug that is swallowed is not absorbed from the gut. Thus, the amount available for systemic activity is only that which is absorbed through the nasal mucosa (in the treatment of rhinitis) or through the alveoli of the lungs (in the treatment of asthma). When laboratory assays of adrenal function or bone formation are measured, FP and other inhaled corticosteroids can be shown to cause suppression of these markers, especially at high doses. There have been no consistent reports of clinical adrenal suppression or osteoporosis caused by FP. In summary, the risk-benefit ratio of FP at the usual doses (therapeutic ratio) is very favorable. High doses may show evidence of suppression of the hypothalamic pituitary axis as measured by in vitro tests, but evidence of corresponding clinical adverse effects is lacking.

Subjective and objective assessments in patients with seasonal allergic rhinitis: effects of therapy with mometasone furoate nasal spray

BACKGROUND

Efficacy of topical nasal steroid therapy for allergic rhinitis is usually evaluated by patient and clinician assessments of subjective symptom changes in diaries and at clinical interviews.

OBJECTIVE

We sought to complement the subjective measures with objective measures of nasal cytology, biochemistry, and function.

METHODS

In this double-blind, randomized study patients with seasonal allergic rhinitis (SAR) 12 years of age or older received 200 microg mometasone furoate nasal spray (n = 80) or placebo spray (n = 41) once daily for 2 weeks. Subjective assessments by clinician and patient comprised symptom/sign scores and overall therapeutic response evaluations. Objective measures included nasal cytology, nasal biochemistry, nasal airway resistance (NAR), mucociliary clearance, and olfactory functions.

RESULTS

Mometasone furoate produced a significantly greater decrease than placebo in subjective measures of SAR for total symptom score (-46% vs -30%, p < 0.05), total nasal score (-47% vs -30%, p < 0.024), individual nasal symptom scores, and overall therapeutic response. The objective measures of eosinophil, basophil, and neutrophil counts and mucociliary clearance were significantly better in mometasone furoate- than in placebo-treated patients. Similarly, within-treatment statistically significant improvements were produced by mometasone furoate but not by placebo sprays for levels of eosinophilic cationic protein, tryptase and albumin, NAR, and odor identification. Significant positive correlations were found between NAR and nasal stuffiness and between eosinophils, basophils, and neutrophils and both eosinophilic cationic protein and albumin.

CONCLUSION

Subjective measures of SAR were significantly improved in the mometasone furoate group by comparison with placebo-treated patients. Objective assessments supported the subjective findings because within-treatment measures were frequently significantly improved after mometasone furoate treatment but not after placebo treatment.

Efficacy and onset of action of fluticasone propionate aqueous nasal spray on nasal symptoms, eosinophil count, and mediator release after nasal allergen challenge in patients with seasonal allergic rhinitis

We studied the effect and onset of action of fluticasone propionate aqueous nasal spray (FPANS) on mediator release and eosinophil accumulation in nasal secretions and on nasal symptoms of patients with seasonal allergic rhinitis after nasal allergen challenge (NAC). At the end of the pollen season, 28 patients were randomized in a double-blind and crossover design to receive 7 days' treatment with FPANS (200 microg, once daily) and matching placebo. NACs were performed before and at 6 h and 1, 2, 3, and 7 days during treatment with FPANS or placebo. Nasal secretions were collected for a quantitative determination of mediators and eosinophil count before and 5 min after each challenge. Nasal symptoms were assessed by scales grading the severity of symptoms at the same time. Results showed that for mediator concentrations there was a significant decrease of leukotriene C4 (P<0.001) at 7 days after the first administration of FPANS as compared to placebo. Two days after FPANS, both eosinophil counts and eosinophil cationic protein (ECP) concentrations were lower than those of placebo (eosinophils: P=0.032; ECP: P=0.038). The onset became even more important at day 7 (eosinophils: P=0.001; ECP: P=0.009) during the FPANS treatment period. For the subjective nasal symptoms, a significant reduction of symptom scores for nasal obstruction occurred also at day 3 (P=0.017) and for sneezing at day 7 (P=0.003). There was not yet any significant improvement of the objective nasal airway resistance after the different NACs during the study period. In conclusion, this study demonstrated that topical fluticasone propionate is effective in the treatment of mucosal inflammation induced by NAC. For optimal control of nasal symptoms induced by repeated maximal allergen challenges, a treatment period of more than 1 week is required.

Intranasal fluticasone propionate reduces ICAM-1 on nasal epithelial cells both during early and late phase after allergen challenge

BACKGROUND

Allergen specific nasal challenge (ASNC) is an optimal method to study the pathophysiological mechanisms sustaining the allergic inflammation and in particular the adhesion molecule system, which is involved in cellular infiltration of nasal mucosa. Topical steroids have been accepted as a highly effective anti-inflammatory therapy for allergic rhinitis.

OBJECTIVE

The aim of this double-blind placebo- controlled study was the evaluation of clinical and cytological parameters, including ICAM-1 expression on nasal epithelial cells, after a 4 week treatment with nasal fluticasone propionate (200 microg/daily) or placebo, using the model of ASNC.

METHODS

Twenty allergic rhinitics underwent nasal challenge before and after treatment. The following parameters were evaluated: (i) nasal symptoms (rhinorrhoea, itching, sneezing, obstruction), (ii) inflammatory cells (eosinophils and neutrophils), (iii) ICAM-1 expression on nasal epithelial cells at baseline, 30 min (early phase) and 6 h (late phase) after ASNC.

RESULTS

Fluticasone propionate was capable of reducing: (i) clinical symptoms during both early (P<0.001) and late phase (P<0.04), (ii) eosinophil (P<0.002) and neutrophil (P<0.001) infiltrate during late phase, and (iii) ICAM-1 expression on nasal epithelial cells during both early (P < 0.01) and late phase (P < 0.03).

CONCLUSIONS

The present results demonstrate that fluticasone propionate exerts a significant action on early and late phase clinical events following specific nasal challenge, reducing also the cellular influx during the late phase. This event is likely due to the modulation of ICAM-1 expression on epithelial cells.

Intranasal beclomethasone reduces allergen-induced symptoms and superficial mucosal eosinophilia without affecting submucosal inflammation

Previous investigations have suggested that nasal secretions, obtained by lavage or scraping, and the nasal submucosa, sampled by biopsy, are two distinct compartments. We investigated the effect of intranasal corticosteroids on antigen-induced eosinophil influx into both compartments. We performed a double-blind, placebo-controlled study in 15 patients with seasonal allergic rhinitis. Beclomethasone dipropionate, 84 microg twice a day, was delivered to one nostril while the other nostril received placebo for 1 wk. Subjects were then challenged with grass or ragweed extracts on each inferior turbinate. Nasal scrapings from both inferior turbinates were obtained before and 24 h after challenge, and bilateral inferior turbinate biopsies were obtained 24 h after challenge, with the subjects still receiving treatment. Intranasal steroids led to a significant reduction in sneezes and eosinophil influx in nasal secretions without affecting the number of eosinophils in the submucosa. Furthermore, intranasal steroids had no effect on the numbers of submucosal EG2+ (activated eosinophils) or CD25+ (IL-2-receptor-bearing) cells, nor did they decrease the endothelial expression of vascular cell adhesion molecule-1 (VCAM-1). These data show that pretreatment with intranasal steroids successfully inhibited the clinical response to allergen and reduced eosinophils in the superficial compartment of the nasal mucosa, but it had no effect on inflammation in the deeper compartment. This might be related to a different distribution of the active medication and antigen into the nasal mucosa or to a specific effect of the active medication on the epithelium resulting in inhibited migration of eosinophils across this layer.

Local corticosteroid treatment: the effect on cells and cytokines in nasal allergic inflammation

Regular and prophylactic use of topical corticosteroids is a well tolerated and effective treatment for allergic rhinitis. The symptomatology of allergic rhinitis is considered to be the result of the accumulation and activation of infiltrating inflammatory cells, releasing mediators, and cytokines. Corticosteroids can suppress many stages of the allergic inflammatory process. This may explain their potent effect on allergic symptomatology. The reduction in cell numbers and probably also cytokines by local corticosteroid therapy differs from cell to cell. Some cells, such as antigen presenting (Langerhans) cells and eosinophils, are highly sensitive to corticosteroid treatment. Others, like T cells, are only significantly reduced in exaggerated situations, for instance after provocation with a high allergen dose or after treatment with a high dose of corticosteroids. Some cells, like macrophages, are not influenced at all.

Intranasal fluticasone propionate for chronic eosinophilic rhinitis in patients with aspirin-induced asthma

We performed a double-blind, crossover, placebo-controlled study on the effect of fluticasone propionate (FP) treatment on chronic eosinophilic rhinosinusitis in 15 patients with aspirin-induced asthma (AIA). There were 10 women and five men aged 32-60 years; average: 45 years. After a 10-day run-in period, patients underwent two 4-week treatment courses (FP vs placebo), separated by a 2-week washout interval. Clinical activity of FP was evaluated by daily measurement of peak nasal inspiratory flow (PNIF) and a scoring system of subjective symptoms. Nasal challenges with E-lysine aspirin, using active anterior rhinomanometry, were performed at the entry and on the last day of each treatment period. Weekly mean values of symptom scores were generally lower and PNIF measurements higher during treatment with FP than with placebo. This difference was statistically significant for most recorded parameters for the whole 4-week FP treatment. On average, the reactions evoked by aspirin nasal challenge were significantly shorter and milder after treatment with FP than with placebo. In 8/13 patients, FP completely prevented aspirin-precipitated nasal reaction, whereas protection after placebo was observed in only 2/12 subjects (P = 0.004). We conclude that intranasal FP is an effective therapy for chronic eosinophilic rhinitis in patients with AIA.

Intranasal fluticasone propionate inhibits recovery of chemokines and other cytokines in nasal secretions in allergen-induced rhinitis

BACKGROUND

Allergen-induced nasal responses are associated with the recovery of proinflammatory mediators and cytokines. In recent years, a distinct group of chemotactic cytokines, chemokines, has been the focus of intense investigation as to their possible role in the pathogenesis of allergic diseases. Although corticosteroids have been known to be effective in the treatment of allergic diseases, their mechanism(s) of action has not been fully elucidated.

OBJECTIVES

To study the effect of topical fluticasone on the recovery of chemokines (IL-8, MIP-1 alpha, and RANTES) and other cytokines (IL-1 beta, IL-6, and GM-CSF) from nasal mucosa following allergen challenge. To correlate the improvement of rhinitis symptoms with cytokine levels during early-phase and late-phase allergic responses.

METHODS

A randomized, double-blind, placebo-controlled crossover study of fluticasone propionate, 200 micrograms q d, was performed in ten subjects with allergic rhinitis. Allergen challenge was administered after 1 week of treatment. Nasal secretions were collected immediately after challenge and during the late-phase reactions; symptom scores were recorded simultaneously. Nasal cytokines were assayed by specific ELISA.

RESULTS

The allergen challenge caused early-phase and late-phase allergic reactions and increased recovery of IL-1 beta, IL-6, IL-8, RANTES, MIP-1 alpha, and GM-CSF from the nasal mucosa. Intranasal fluticasone inhibited the allergen-induced increase in nasal symptoms. This was associated with decreases in cytokine recovery. A significant correlation was observed between decreases in cytokine levels and in symptom scores after treatment.

CONCLUSION

Our results suggest that treatment with topical fluticasone propionate inhibits allergen-induced nasal responses and the associated increase in the production/secretion of chemokines and other proinflammatory cytokines.

Effects of inhaled steroid treatment on serum eosinophilic cationic protein (ECP) and low affinity receptor for IgE (Fc epsilon RII/sCD23) in childhood bronchial asthma

Serum eosinophilic cationic protein (ECP) and soluble low affinity receptor for IgE (Fc epsilon RII/sCD23) concentrations were measured in relation to symptom-medication scores, pulmonary function, and total IgE levels in 27 chronic allergic asthmatic children (17 boys, 10 girls), mean age 10.8 years, before and at the end of a three month inhaled corticosteroid (budesonide) treatment period. Serum ECP and sCD23 concentrations were also measured in age matched non-asthmatic controls with allergic rhinitis. All asthma patients had significantly higher serum ECP and sCD23 than the controls, whereas the mean serum IgE was not different. No correlation between total IgE concentrations and serum sCD23 could be detected in either group. At the end of the treatment period, symptom-medication scores and pulmonary function improved. Serum ECP and sCD23 concentrations were reduced; however, total IgE values did not change significantly. A significant relation was found between the improvement of symptom-medication scores and fall in both sCD23 and ECP concentrations. Although there was a significant correlation of pulmonary function values with serum ECP, no such relation was observed for sCD23. It appears that serum sCD23 and ECP concentrations could be good disease markers, particularly in asthma. Monitoring of serum inflammation markers, especially ECP, may be useful in the follow up of asthmatic children on anti-inflammatory treatment.

The rationale for use of topical corticosteroids in allergic rhinitis

The rationale for using topical corticosteroids in the treatment of allergic rhinitis is that high drug concentrations can be achieved at receptor sites in the nasal mucosa, with minimal risk of systemic adverse effects. Topical corticosteroids have been demonstrated to reduce the number of Langerhans' cells (or their markers) in the nasal mucosa, and this is thought to attenuate antigen presentation. T lymphocytes have been identified as being significant in orchestrating the immune-inflammatory response, particularly the TH2 cells, which represent an important target for topical corticosteroids. TH2 cell-evoked mast cells and basophils are the sole producers of histamine, a mediator of major importance for rhinitis symptoms. Several studies have shown that the increased number of mast cells and basophils in the epithelium following antigen challenge/exposure, are markedly reduced by topical corticosteroids. Furthermore, the number of eosinophils, an important morphological marker of allergic rhinitis, can be profoundly reduced by treatment with topical corticosteroids. The rationale for topical treatment is strengthened by evidence of inhibition of cytokine release from surface epithelial cells, resulting in reduced recruitment and activation of mast cells, basophils, and eosinophils, which may be attributed to the high drug concentration achieved in epithelial cells. Ongoing inflammation in the mucous membrane is indicated by entry of plasma into the nasal lumen which subsides with the anti-inflammatory efficacy of topical corticosteroids. In contrast to antihistamine therapy, which has little effect on nasal blockage, pretreatment with topical corticosteroids results in almost complete attenuation of late-phase symptoms including nasal blockage, and moderate efficacy in early phase symptoms. Clearly, the spectrum of anti-inflammatory activity afforded by topical corticosteroid therapy is of clinical significance in reducing the three major symptoms of allergic rhinitis- sneezing, watery rhinorrhoea and nasal blockage.

Topical corticosteroids potentiate mucin secretion in the normal nose

The exact mode of action of topical nasal corticosteroids is still uncertain. The aim of this study was to determine their effects on microvascular permeability and cellular and glandular secretion by measuring the levels of total protein, albumin, lysozyme and mucin recovered in nasal lavage fluid before and after 3 weeks of treatment with a topical nasal corticosteroid in 12 normal non-atopic subjects. Six subjects applied 200 micrograms fluticasone propionate and six applied 200 micrograms beclomethasone dipropionate to one nostril in each 24 h: matched placebo was applied to the other nostril. There was a significant rise in the level of mucin recovered compared with baseline values following fluticasone administration (baseline 76.2 micrograms/ml (mean) +/- 5.5 (SEM), fluticasone 118.3 micrograms/ml +/- 11.6 P = 0.015) and beclomethasone administration (baseline 64.3 micrograms/ml +/- 6.6, beclomethasone 87.2 micrograms/ml +/- 4.8, P = 0.041). There was no significant change in the levels of total protein, albumin or lysozyme following either active medication or placebo treatment. Topical corticosteroids appear to potentiate mucin secretion and do not alter serous secretion or microvascular permeability in the unchallenged non-atopic nose.

Effect of six-hour exposure to nitrogen dioxide on early-phase nasal response to allergen challenge in patients with a history of seasonal allergic rhinitis

BACKGROUND

Recent studies have suggested that exposure to air pollutants may enhance the airway responsiveness of susceptible individuals to inhaled allergen.

METHODS

To investigate the effect of exposure to nitrogen dioxide (NO2) on nasal airways resistance (NAR) and inflammatory mediators in nasal lavage fluid, eight subjects with a history of seasonal allergic rhinitis, who were tested out of season, were exposed in a randomized single-blind, crossover study to either air or 400 ppb NO2 for 6 hours. The changes in NAR and eosinophil cationic protein (ECP), mast cell tryptase (MCT), neutrophil myeloperoxidase (MPO), and interleukin-8 (IL-8) in nasal lavage fluid before and after exposure were evaluated. Another group of eight subjects with a history of seasonal allergic rhinitis were also randomized to exposure to air or 400 ppb NO2 for 6 hours and then challenged with allergen, before evaluation for changes in NAR and changes in ECP, MCT, MPO, and IL-8 in nasal lavage fluid.

RESULTS

Exposure to air or NO2 did not alter either NAR or the levels of ECP, MCT, MPO, or IL-8 in nasal lavage fluid. Allergen challenge after exposure to both air and NO2 significantly (p < 0.05) increased levels of MCT, but not MPO and IL-8 in the nasal lavage fluid. In addition, allergen challenge after exposure to NO2 but not air, significantly increased levels of only ECP in nasal lavage fluid (p < 0.05).

CONCLUSIONS

These results suggest that acute exposure to NO2 at concentrations found at the curbside in heavy traffic during episodes of pollution, may "prime" eosinophils for subsequent activation by allergen in individuals with a history of seasonal allergic rhinitis.

Effect of intranasal fluticasone proprionate on the immediate and late allergic reaction and nasal hyperreactivity in patients with a house dust mite allergy

BACKGROUND

Patients with perennial allergic rhinitis develop nasal symptoms not only after allergen exposure, but generally also after non-specific stimuli.

OBJECTIVE

To evaluate the effect of 2 week's treatment with fluticasone propionate aqueous nasal spray (FPANS) on the nasal clinical response, inflammatory mediators and nasal hyperreactivity.

METHODS

Twenty-four rhinitis patients allergic to house dust mite (HDM), participated in a double-blind, placebo-controlled crossover study. After 2 week's treatment with placebo or 200 micrograms FPANS twice daily, patients were challenged with HDM extract. Symptoms were recorded and nasal lavages were collected for up to 9.5 h after challenge. Nasal hyperreactivity was determined by histamine challenge 24 h later.

RESULTS

Because of a carry-over effect for the immediate symptom score, for this variable only the data from the first treatment period were used. FPANS treatment resulted in a significant decrease of nasal symptoms with 70%, 69% and 63% after 100, 1000 and 10,000 Biological Units (BU)/mL of HDM extract respectively. Active treatment resulted in a 76% decrease of the late-phase symptoms. FPANS treatment significantly reduced albumin influx after HDM 1000 BU/mL with 62% and tended to reduce tryptase release after HDM 1000 BU/mL (P = 0.0629). During the late phase FPANS treatment reduced albumin influx with 67% and eosinophil cationic protein (ECP) release with 83%. No effect of FPANS was seen on histamine levels. FPANS significantly decreased histamine-induced symptom score with 34%, secretion with 32% and sneezes with 41%.

CONCLUSION

FPANS significantly inhibits the immediate and late allergic response, and nasal hyperreactivity, probably by suppressing mast cells and eosinophils in the nasal mucosa.

Contralateral differences among biomarkers determined by a modified nasal lavage technique after unilateral antigen challenge

The concentration of biomarkers from vessels and inflammatory cells in nasal lavage fluid reflects the degree of hyperresponsiveness in patients with allergic rhinitis. The lavage has usually been performed of both nasal cavities together after prewashings and administration of decongestants. To improve the technique, we introduced a modification involving lavage of the nasal cavities separately without any prewashings or decongestants. We challenged 20 rhinitic subjects sensitive to timothy unilaterally with timothy extract. In nasal lavages performed before, immediately after, and 6 h after the challenge, we determined the concentrations of albumin, histamine, bradykinin, TAME (N-alpha-tosyl-L-arginine methyl ester)-esterase, and leukotriene C4 (LTC4). In eight subjects, the procedure was repeated 1 and 2 weeks later. After the challenge, albumin, bradykinin, TAME-esterase, and LTC4 in the nasal lavage fluid increased on the ipsilateral side but not on the contralateral side. Histamine did not increase after antigen challenge. After 6 h, the biomarkers were not increased. The concentrations of biomarkers did not differ between sides before the challenge and not between visits. Thus, the modified nasal lavage technique is reliable and improved compared to previous methods because it involves reproducible determinations of different biomarkers, and it is simple and easy to perform.

The effect of fluticasone propionate aqueous nasal spray on nasal mucosal inflammation in perennial allergic rhinitis

Mast cell degranulation, and the subsequent recruitment of infiltrating inflammatory cells, such as eosinophils, into the nasal mucosa has long been considered the most important model to explain allergic rhinitis. Several studies show a decrease in the number of eosinophils and possibly also mast cells during local corticosteroid treatment. Over the last decade, a new model to explain allergic inflammation has evolved. In this model, Langerhans' cells and T-cells play an important role. Langerhans' cells possess a high affinity receptor for IgE. In patients with allergic rhinitis, allergen provocation results in stimulation of T-cells by the IgE-positive Langerhans' cells. The T-cells produce a number of cytokines which stimulate IgE production as well as the inflammatory reaction. The number of T-cells is not usually influenced by corticosteroid treatment; however, the function of the T-cells, shown by the spectrum of cytokines produced, is clearly influenced. The cells that are most dramatically affected by local corticosteroid treatment are the Langerhans' cells, which completely disappear during treatment. This decrease suggests that there is a reduction in antigen presentation. The subsequent decrease in T-cell stimulation may result in a reduction of the reactions that are dependent on T-cell-derived mediators.

Effect of inhaled beclomethasone dipropionate on expression of proinflammatory cytokines and activated eosinophils in the bronchial epithelium of patients with mild asthma

Increasing evidence suggests that cytokines play a role in airway inflammation by attracting and activating inflammatory cells. This may lead to epithelial cell damage and airway hyperresponsiveness. Bronchial provocative concentration of histamine causing a 20% fall in forced expiratory volume in 1 second was measured in patients with mild asthma, and bronchial biopsy specimens were stained for granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin (IL)-8, and activated eosinophils (EG2) in the bronchial epithelium. The effect of inhaled beclomethasone dipropionate was also assessed in a placebo-controlled double-blind manner. There was a correlation between GM-CSF expression and EG2-staining cells (r = 0.484 p < 0.05) in the epithelium. Provocative concentration of histamine causing a 20% fall in forced expiratory volume in 1 second was correlated with GM-CSF expression (r = -0.462, p < 0.05). Treatment with inhaled beclomethasone dipropionate 500 micrograms twice a day led to a significant decrease in both the expression of GM-CSF (p < 0.01) and IL-8 (p < 0.02) and the number of EG2-staining cells (p < 0.01) in the epithelium. The changes in GM-CSF (r = 0.798, p < 0.01) and IL-8 (r = 0.653, p < 0.02) expression were correlated with the changes in EG2-staining cells after treatment. These results suggest that GM-CSF may influence eosinophil activation in the epithelium in vivo and participate in the etiology of bronchial hyperresponsiveness in mild asthma. Also, beclomethasone dipropionate may inhibit eosinophil activation partly by downregulating the expression of GM-CSF and IL-8 in the bronchial epithelium.

Effect of short-term treatment with fluticasone propionate nasal spray on the response to nasal allergen challenge

The aim of the study was to investigate the effect of short-term treatment with fluticasone propionate on the response to nasal allergen challenge in patients with allergic rhinitis. Responses to nasal allergen challenge were assessed subjectively by recording symptom scores on visual analogue scales, and objectively by measuring histamine, PGD2 and LTC4 in nasal lavage and by measuring nasal inspiratory peak flow following challenge. Nasal allergen challenge resulted in an increase in all symptom scores (P < 0.05); an increase in histamine and PGD2 (P < 0.05), and a decrease in nasal inspiratory peak flow at 1 h, 5 h and 7 h following challenge (P < 0.05). The allergen-induced changes in symptom scores, mediator levels and nasal inspiratory peak flow were attenuated by treatment with fluticasone propionate (P < 0.05 for all parameters measured). Post-challenge nasal obstruction was decreased by 45%; sneezing, itching and rhinorrhoea by 73, 78 and 80% respectively in the group as a whole comparing scores whilst on fluticasone propionate with those on no therapy. Fluticasone propionate, 200 micrograms twice daily for 2 weeks is effective in reducing significantly the early and late response to nasal allergen challenge.

Influence of prolonged treatment with topical corticosteroid (fluticasone propionate) on early and late phase nasal responses and cellular infiltration in the nasal mucosa after allergen challenge

We have examined the effect of prolonged treatment with topical corticosteroid on allergen-induced early and late nasal responses and the associated inflammatory cell infiltrate in grass pollen sensitive allergic rhinitics. Following a randomized double-blind 6 week treatment period with fluticasone propionate 200 micrograms aqueous nasal spray twice daily or matched placebo spray, nasal provocation was performed using Timothy grass pollen extract. Nasal symptoms were recorded at intervals from 0 to 24 h. Nasal biopsies were performed before treatment and at 24 h after allergen and processed for immunohistology. When corticosteroid-treated patients were compared with the placebo group there was an approximately 50% decrease in the size of the early (0-60 min) response and almost complete inhibition of late (1-24 h) nasal symptoms after allergen challenge. After allergen challenge markedly fewer T lymphocytes and CD25+ (interleukin-2 receptor bearing) cells were observed in both the epithelium and submucosa in fluticasone treated patients compared with the placebo group. Significantly less total and activated eosinophils were observed, particularly within the nasal epithelium. Submucosal mast cell counts were decreased, whereas increased numbers of submucosal neutrophils were observed. These results confirm that topical corticosteroid treatment inhibits allergen-induced early and late nasal responses. This may possibly occur following a decrease in T lymphocytes and/or mast cells and their products and a consequent reduction in tissue eosinophilia.

Inhaled fluticasone propionate. A review of its pharmacodynamic and pharmacokinetic properties, and therapeutic use in asthma

Fluticasone propionate is an androstane carbothioate glucocorticosteroid with almost twice the topical anti-inflammatory potency of beclomethasone dipropionate. Importantly, it is not appreciably absorbed from the gastrointestinal tract. However, the fraction of active drug absorbed from the lungs after inhalation, and therefore total systemic availability, has yet to be determined. Inhaled fluticasone propionate administered at dosages of 1500 micrograms/day for 1 year or 2000 micrograms/day for 6 weeks did not cause clinically significant pituitary-adrenal suppression. Preliminary data from 2 published trials also indicate no significant effect on growth in children. However, wider clinical experience is needed to clarify the effects of long term administration on pituitary-adrenal function, bone metabolism and attainment of adult height in children. In clinical studies, inhaled fluticasone propionate was at least as effective as beclomethasone dipropionate or budesonide when administered at half the dosage of the comparators in patients with mild to moderate or severe asthma. Limited data suggest that fluticasone propionate also has considerable potential in the management of childhood asthma. In trials of up to 1 year in duration, fluticasone propionate appeared to be well tolerated by both adults and children. Whether an improved tolerability profile compared with other corticosteroids is a major clinical benefit of the extremely low oral bioavailability of inhaled fluticasone propionate requires confirmation. Nevertheless, on the basis of available data from initial clinical trials of mostly limited duration, inhaled fluticasone propionate offers an effective treatment option for the management of asthma, with the potential of an enhanced safety profile.

Serum eosinophil cationic protein during treatment of asthma in children

BACKGROUND

Serum eosinophil cationic protein (ECP) is suggested to reflect the degree of bronchial inflammation and hyperreactivity in patients with asthma. We measured serum ECP levels before and 1 and 5 months after treatment with inhaled budesonide (n = 10) or sodium cromoglycate (SCG) (n = 7) in children with asthma.

METHODS

The daily dose of budesonide was 800 micrograms/m2 during the first month and 400 micrograms/m2 during the next 4 months. ECP levels were determined by radioimmunoassay.

RESULTS

ECP decreased during the 5 months of treatment (p = 0.020 for treatment groups combined; p = 0.049 for the budesonide group; p = NS for the SCG group). The higher the serum ECP level at entry, the more it decreased during treatment, both in the budesonide group (r = -0.697, p < 0.05) and in the SCG group (r = -0.893, p < 0.05). No correlation was found between the ECP level and the ratio of forced expiratory volume in 1 second to forced vital capacity (FEV1%) or between changes in these. However, basal pulmonary function was reduced in 8 of 16 subjects only, and FEV1% did not change significantly in either group. Thus the absence of a correlation is understandable.

CONCLUSIONS

The clinical value of the sensitive decrease in serum ECP remains to be established.

Mast cells and mediators in the nasal mucosa after allergen challenge. Effects of four weeks' treatment with topical glucocorticoid

The study focuses on the relationship between the tissue density of mast cells, the tissue histamine levels and the levels of markers of mast cell activation after an allergen challenge of the nasal mucosa of allergic patients. The effect of 4 weeks' treatment with a topical glucocorticoid, fluticasone propionate, was studied in a double-blind, placebo-controlled study of 25 hay fever patients. Nasal biopsies were obtained before and after the treatment period for the evaluation of mast cell density and tissue histamine levels. Nasal challenges were performed at 2-week intervals for 8 weeks using a standardized nasal lavage model. TAME-esterase was analysed in the returned lavage fluid from all the challenges (weeks 0-8), while the levels of histamine and tryptase were analysed in lavage fluids from challenges performed before and after the treatment period (weeks 0 and 4). The symptoms of nasal allergy were assessed after each challenge. Treatment with fluticasone propionate did not influence mast cell density, the tissue histamine concentration, the lavage histamine levels or the TAME-esterase activity, while a reduction in nasal symptoms and tryptase in nasal lavage fluid was revealed. Our present study again emphasizes the fact that the mast cell is an important trigger cell in the immediate nasal allergic response. The study also demonstrates the usefulness of the measurements of tryptase as an indicator of both mast cell activation and the efficacy of topical steroid treatment.