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

[T-cell immune responses in chronic inflammatory diseases of the nasal mucosa]

Acute rhinosinusitis and chronic rhinosinusitis are inflammatory diseases of the mucosal membranes due to mislead immunological reactions to aeroallergens. T‑cells are divided into different groups based on their cytokine secretion: T‑helper type 1 (Th1) and type 2 (Th2) cells. The allergic immune response is caused by activation of specific Th2 cells. With specific immunotherapy, the mislead hyperactivated "allergic" immune response is reduced to a reaction within the normal range. The inflammatory forms of chronic rhinosinusitis are called endotypes, and, in the future, could enable a targeted, pathomechanistic therapy. These endotype-based treatment approaches target specific signaling pathways that have already shown good effects for chronic rhinosinusitis with nasal polyps using monoclonal antibodies. However, so far, only selected patients with non-rhinologic indications, off-label treatments, or in clinical trials have benefited from these treatments.

Cytokine expression in allergic inflammation: systematic review of in vivo challenge studies

BACKGROUND

Allergic inflammatory responses are driven by cells of the immune system that rely on cytokines to regulate the activity of other immune and structural cells.

OBJECTIVE

To review published studies to (1) identify cytokines consistently increased after allergen challenge in atopic patients and (2) investigate temporal variation in cytokine expression.

METHODS

A PUBMED systematic search was used to extract data from studies involving analysis of cytokine expression in fluids or biopsies following in vivo allergen challenge in atopic patients.

RESULTS

Data were extracted from 82 studies. There were no consistent reports of cytokine protein increase in fluids of patients at 0-1 h after challenge. At 4-12 h, the chemokines eotaxin, macrophage inflammatory protein-1alpha, RANTES (regulated on activation normal T cell expressed and secreted) and interleukin (IL)-8 have all been consistently reported to be up-regulated. At 18-24 h after challenge, the lymphokines IL-4, IL-5 and IL-13, as well as the pro-inflammatory cytokines granulocyte-macrophage colony-stimulating factor, tumour necrosis factor-alpha and IL-6 are consistently increased when compared with the respective control value. There were no reports of up-regulation in interferon-gamma protein and mRNA and in IL-2 mRNA.

CONCLUSION

The expression of granulocyte-macrophage colony-stimulating factor is consistently increased in tissues at 4-12 h after challenge. The influence of this cytokine on antigen capture and presentation by dendritic cells should be further investigated. Additionally, allergen challenge studies are needed that investigate the expression of macrophage-derived chemokine and thymus-regulated and activation-regulated chemokine in tissues of atopic patients. Blocking the effects of these lymphocyte-specific chemokines might provide new therapeutic approaches for the control of allergic inflammation.

Mode of action of intranasal corticosteroids

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

Cytologic distinctions between clinical groups using curette-probe compared to cytology brush

BACKGROUND

We had previously used curette-probe (Rhinoprobe; Arlington Scientific, Springville, UT) to study nasal cytology in various types of patients. Because of the potential sampling ease of using a brush, we sought to compare cytological results obtained with a curette-probe with those obtained using a cytology brush (Cytobrush Plus; Medscand, Malmö, Sweden).

OBJECTIVE

To compare the ability of samples of nasal leukocytes obtained with a curette-probe versus a cytology brush to distinguish clinical categories of patients attending an allergy clinic.

METHODS

Adult allergy clinic patients were studied by both curette-probe and cytology brush sampling. Quantitation of eosinophils and total leukocytes was performed on samples. Comparisons of cell quantities for each sampling method were made in patients classified into clinical groups. Patients with rhinitis complaints and abnormalities of nasal mucosal appearance with or without aeroallergy were compared with other patients. The adjustment of leukocyte quantities for the numbers of epithelial cells observed was also analyzed. Sampling methods were also compared for receiver operating characteristics.

RESULTS

Curette-probe sample leukocyte quantities distinguished patients with symptoms of rhinitis (SR) with abnormal nasal appearance from other patients. This between-group distinction was more significant for leukocyte numbers normalized for the number of epithelial cells. SR patients with both abnormal nasal appearance and aeroallergy had significantly more eosinophils and less goblet cells than other patients. Greater than five curette-probe eosinophils were only observed in patients with SR. Brush samples did not show differences between patients stratified in these ways, and eosinophils were observed in patients without SR. Receiver operating characteristics favored curette-probe samples in terms of leukocyte or eosinophil increases characterizing their respective symptomatic patient subgroups.

CONCLUSIONS

Curette-probe-obtained nasal samples allow for leukocyte and eosinophil quantitations which characterize rhinitis patients better than brush-obtained samples. Total leukocyte quantitations obtained by curette-probe may represent a marker of inflammatory nasal disease in adults undergoing allergy evaluation and treatment for rhinitis.

Airway mast cells and eosinophils correlate with clinical severity and airway hyperresponsiveness in corticosteroid-treated asthma

BACKGROUND

The relationship between airway inflammation and asthma severity in corticosteroid-treated asthma is unclear.

OBJECTIVES

Our purpose was to characterize the inflammatory cell profile of the airway lumen and epithelium in corticosteroid-treated asthma and to relate these findings to clinical and physiologic markers of asthma severity.

METHODS

Adults (n = 20) with asthma received standardized high-dose inhaled corticosteroid therapy with beclomethasone 2000 microgram per day for 8 weeks. Airway responsiveness to methacholine and hypertonic (4.5%) saline solution was then assessed, followed by sputum induction and, 1 week later, bronchoscopy with bronchoalveolar lavage and bronchial brush biopsy to assess inflammatory cells.

RESULTS

Clinical asthma severity was associated with airway hyperresponsiveness. Metachromatic cells were the main granulocyte present in bronchial brush biopsy specimens and correlated with airway responsiveness to saline solution (r = -0.75), methacholine (r = -0.74), peak flow variability (r = 0.59), and clinical asthma severity (r = 0.57). Eosinophils were the main granulocyte present in sputum and correlated with airway responsiveness to saline solution (r = -0.63) but not with other clinical markers of asthma severity. Bronchoalveolar lavage cell counts were not related to clinical asthma severity.

CONCLUSIONS

In asthmatic patients treated with cortico-steroids, the dominant inflammatory effector cell in the epithelium is the metachromatic cell, and in sputum it is the eosinophil. These cells correlate with the degree of airway hyperresponsiveness. Clinical asthma severity correlates with airway responsiveness and epithelial metachromatic cells. Induced sputum eosinophils and airway responsiveness to hypertonic saline solution may be useful markers of airway inflammation for clinical practice.

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.