Nasal mucosal mast cells and histamine in hay fever. Effect of topical glucocorticoid treatment

Non-Invasive Nasal Discharge Fluid and Other Body Fluid Biomarkers in Alzheimer’s Disease

The key to current Alzheimer’s disease (AD) therapy is the early diagnosis for prompt intervention, since available treatments only slow the disease progression. Therefore, this lack of promising therapies has called for diagnostic screening tests to identify those likely to develop full-blown AD. Recent AD diagnosis guidelines incorporated core biomarker analyses into criteria, including amyloid-β (Aβ), total-tau (T-tau), and phosphorylated tau (P-tau). Though effective, the accessibility of screening tests involving conventional cerebrospinal fluid (CSF)- and blood-based analyses is often hindered by the invasiveness and high cost. In an attempt to overcome these shortcomings, biomarker profiling research using non-invasive body fluid has shown the potential to capture the pathological changes in the patients’ bodies. These novel non-invasive body fluid biomarkers for AD have emerged as diagnostic and pathological targets. Here, we review the potential peripheral biomarkers, including non-invasive peripheral body fluids of nasal discharge, tear, saliva, and urine for AD.

Spectrum of Seasonal Allergic Rhinitis Symptom Relief with Topical Corticoid and Oral Antihistamine Given Singly or in Combination

Sixty ragweed-sensitive volunteers participated in a 2-week study that compared symptom profiles during treatment with antihistamine (loratadine, LOR) alone, topical corticoid (beclomethasone, BEC) alone, or the two drugs combined. For 5 days commencing shortly after the beginning of the ragweed bloom, patients took no treatment while we collected baseline data. They were then randomized to one of the three treatments, receiving that treatment for the balance of the 2-week study term. Twice each day they recorded the severity of congestion, eye symptoms, running and blowing, itching, and sneezing. At the end of the study they provided an estimate of overall symptom relief, which favored combined treatment (vs LOR P = 0.001, vs BEC P = 0.042). To gain an estimate of disease severity and treatment effectiveness over time, and to smooth out day-to-day variation, we divided symptom diary reports into three segments (days 2–4, 5–7, and 8–10) for analysis. Combined treatment controlled symptoms better than antihistamine alone in nearly all study segments. Corticoid alone or combined with antihistamine provided similar control of congestion, running and blowing, and eye complaints. Combination therapy controlled itching and sneezing better, especially through the study segments 1 and 2. Patient preference for combined treatment seems to relate to control of itching and sneezing and rapid onset of effect.

Risk multipliers for severe food anaphylaxis

Anaphylaxis is a severe, life threatening allergic reaction. In most fatal cases of food anaphylaxis, the fatality is not due merely to a simple, linear relationship between the allergen and exposure in a sensitized individual. Compounding factors such as the allergic disease burden—particularly the presence of asthma; comprehension of the potential severity of an event, training in the appropriate use of epinephrine, and emerging metabolic factors should be considered when assessing risk and establishing management strategies. This paper reviews the factors that contribute to the risk of severe anaphylactic events and provides a framework for the ongoing management of patients at risk of severe food allergy.

Clinical benefits of combination treatment with mometasone furoate nasal spray and loratadine vs monotherapy with mometasone furoate in the treatment of seasonal allergic rhinitis

BACKGROUND

Intranasal corticosteroids and nonsedating antihistamines are the drug classes most often prescribed to treat allergic rhinitis (AR). Treatment guidelines recommend a combination of these agents for moderate-to-severe AR. However, clinical studies have found that combining an antihistamine with an intranasal corticosteroid provides few or no advantages over monotherapy with an intranasal corticosteroid.

OBJECTIVE

To compare the efficacy of mometasone furoate nasal spray (NS) plus loratadine with that of monotherapy with the individual agents in patients 12 years and older with at least a 2-year history of seasonal AR.

METHODS

In a multicenter, randomized, double-blind, parallel-group, placebo-controlled clinical study, 702 patients were randomized to receive mometasone furoate NS, 200 microg, plus loratadine, 10 mg (n = 169); mometasone furoate NS, 200 microg (n = 176); loratadine, 10 mg (n = 181); or placebo (n = 176) once daily for 15 days. Primary efficacy variables were total nasal symptom score (TNSS) and total symptom score (TSS) as recorded on diary cards.

RESULTS

No statistically significant differences were observed between mometasone furoate NS plus loratadine and mometasone furoate NS monotherapy for the primary efficacy variables. For TNSS and TSS, all 3 active drug therapies were more effective than placebo (P < or = .02). Both mometasone furoate NS treatment regimens were more effective than loratadine or placebo for TNSS (P < .01 for both) and TSS (P < or = .03 for both), whereas loratadine was more effective than placebo for TNSS only (P = .02).

CONCLUSIONS

Combination therapy with mometasone furoate NS and loratadine provided benefits similar to monotherapy with mometasone furoate NS for the symptoms of seasonal AR. Therefore, mometasone furoate NS monotherapy was shown to be an effective treatment for seasonal AR.

Topical glucocorticosteroids in rhinitis: mode of action

The introduction of nasal glucocorticosteroids, more than 30 years ago, represents the most important therapeutic progress in rhinitis management since the introduction of the first generation of antihistamines. Our knowledge of the mode of action of glucocorticosteroids in the nose has improved as the airway mucous membrane of the nose is easily accessible for investigation. However, the exact mechanism behind the marked clinical effect remains unclear. The present article presents some of the important effects of topical glucocorticosteroids on pathophysiological events in the nasal mucosa.

Comparison of intranasal corticosteroids and antihistamines in allergic rhinitis: a review of randomized, controlled trials

For several years there has been discussion of whether first-line pharmacological treatment of allergic rhinitis should be antihistamines or intranasal corticosteroids. No well documented, clinically relevant differences seem to exist for individual nonsedating antihistamines in the treatment of allergic rhinitis. Likewise, the current body of literature does not seem to favor any specific intranasal corticosteroid. When comparing efficacy of antihistamines and intranasal corticosteroids in allergic rhinitis, present data favor intranasal corticosteroids. Interestingly, data do not support antihistamines as superior in treating conjunctivitis associated with allergic rhinitis. Safety data from comparative studies in allergic rhinitis do not indicate differences between antihistamines and intranasal corticosteroids. Combining antihistamines and intranasal corticosteroids in the treatment of allergic rhinitis does not provide additional beneficial effects to intranasal corticosteroids alone. Considering present data, intranasal corticosteroids seem to offer superior relief in allergic rhinitis, when compared with antihistamines.

Intranasal corticosteroids for allergic rhinitis: superior relief?

Whether first-line pharmacological treatment of allergic rhinitis should be antihistamines or intranasal corticosteroids has been discussed for several years. First-generation antihistamines are rarely used in the treatment of allergic rhinitis, mainly because of sedative and anticholinergic adverse effects. On the basis of clinical evidence of efficacy, no second-generation antihistamine seems preferable to another. Similarly, comparisons of topical and oral antihistamines have been unable to demonstrate superior efficacy for one method of administration over the other. Current data documents no striking differences in efficacy and safety parameters between intranasal corticosteroids. When the efficacy of antihistamines and intranasal corticosteroids are compared in patients with allergic rhinitis, present data favours intranasal corticosteroids. Interestingly, data do not show antihistamines as superior for the treatment of conjunctivitis. Safety data from comparative studies in patients with allergic rhinitis do not indicate differences between antihistamines and intranasal corticosteroids. Combining antihistamines and intranasal corticosteroids in the treatment of allergic rhinitis does not provide any additional effect to intranasal corticosteroids alone. On the basis of current data, intranasal corticosteroids seem to offer superior relief in allergic rhinitis than antihistamines.

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.

Increase in epithelial mast cell numbers in the nasal mucosa of patients with perennial allergic rhinitis

The aim of the study was to compare the numbers and distribution of mast cells in the nasal mucosa of perennial allergic rhinitis (PAR) patients and controls, as demonstrated by different staining methods for light microscopy. Biopsies of inferior turbinate mucosa were taken from 10 patients with PAR and 10 patients undergoing septoplasty or septorhinoplasty (control group). Sections for light microscopy were stained with azure A. chloroacetate esterase and an ABC immunohistochemical technique using antibody to tryptase. Three times more mast cells were found in the epithelium of PAR patients compared to controls using the immunohistochemical technique (p = 0.0074). This method demonstrated considerably more mast cells than the other stains. The increase in epithelial mast cells is consistent with the migration of mast cells seen in seasonal allergic rhinitis, and this may be important in the phenomenon of nasal priming seen after repeated antigen exposure.

Effect of intranasal azelastine and beclomethasone dipropionate on nasal symptoms, nasal cytology, and bronchial responsiveness to methacholine in allergic rhinitis in response to grass pollens

BACKGROUND

We compared the effect of nasal azelastine (0.56 mg/day), nasal beclomethasone dipropionate (BDP, 200 micrograms/day) and matched placebo on seasonal symptoms, nasal cytology, and the increase in bronchial responsiveness occurring during pollen season in a group of subjects with history of allergic rhinitis to grass pollens only.

METHODS

The study was completed by nine subjects in the azelastine group, 13 subjects in the BDP group, and 13 subjects in the placebo group. Treatments were randomly administered for 6 weeks. Each subject recorded daily nasal, eye and chest symptoms and additional treatment requirement for the entire pollen season. Each subject performed nasal lavage 4 weeks into the pollen season. Bronchial responsiveness to methacholine was measured before and 4 weeks into the pollen season. Response was expressed as provocative dose causing a 20% fall in forced expiratory volume in 1 second in micromoles.

RESULTS

Azelastine-treated subjects had significantly fewer nasal symptoms during week 4 (p < 0.05), and BDP-treated subjects had fewer nasal symptoms during week 4 (p < 0.05) and week 5 (p < 0.05) compared with subjects given placebo. Both treatments significantly reduced the need for additional medications. BDP, but not azelastine, treatment significantly reduced the percent of eosinophils recovered in nasal lavage (p < 0.05). Neither azelastine nor BDP protected against the increase in bronchial responsiveness to methacholine occurring during the pollen season.

CONCLUSION

We demonstrated that both azelastine and BDP are effective treatments for nasal symptoms of seasonal allergic rhinitis after 4 weeks of therapy. However, we were not able to demonstrate an antiinflammatory activity of nasally administered azelastine. Nasal therapy with azelastine and BDP did not block the increase in bronchial responsiveness to methacholine caused by seasonal allergen exposure.

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.

Histamine metabolism in nasal polyps

We attempted to determine the relationship of nasal polyps to histamine (HA) metabolism. Compared to that in allergy-related nasal polyps and infection-related nasal polyps, the level of HA in aspirin-induced asthma-related polyps was significantly lower. Large differences between the groups were not observed in HA-synthesizing enzyme activity, but degradative enzyme activity was much higher in aspirin-induced asthma-related polyps than in other types of nasal polyps tested. These findings suggest the possibility that the amount of HA in polyps associated with aspirin-induced asthma was less because of greatly enhanced degradation. We found, in addition, that in nasal tissues such as polyps, histamine-N-methyl transferase, rather than histaminase, was the principal degradative enzyme.

A gap in surface therapy: topical antihistamines

Allergic and non-allergic rhinitis have been treated by many drugs with different modes of action such as topical disodium cromoglycate and ipratropium bromide, systemic antihistamines and corticosteroid drugs and topical corticosteroids. Yet, these therapies are not entirely satisfactory for all symptoms. The rationale for the topical, intranasal use of antihistamines in patients is discussed. Topical antihistamine agents are administered in order to avoid the side effects of systematically applied medications, and to reach higher local drug concentrations. H1 receptors of the nasal mucosa play an important role in the physiopathology of allergic and non-allergic rhinitis and even of infectious rhinitis. Most studies using topical antihistamines in rhinitis, had an experimental physiopathological aim and did not explore clinical efficacy. Recently, topical application of levocabastine--a potent H1 antagonist--yielded good clinical results in allergic conjunctivitis, seasonal allergic rhinoconjunctivitis, and non allergic perennial rhinitis.

Corticosteroid treatment reduces mast cell numbers in inflammatory bowel disease

Mast cell degranulation in the gut causes mucus secretion, mucosal edema, and increased gut permeability and may be responsible for some of the symptoms and signs of inflammatory bowel disease. We have used a novel monoclonal antibody (AAI) against tryptase expressed exclusively in the granules of mast cells to enumerate mast cells in rectal biopsies in order to study the effect of inflammatory bowel disease and drug treatment upon rectal mast cell numbers. Rectal mast cell numbers are significantly reduced in inflammatory bowel disease patients taking corticosteroids (mean 4.95 cells/mm2) when compared with control patients (10.1, P less than 0.001) and inflammatory bowel disease patients not taking corticosteroids (9.7, P less than 0.001 Wilcoxon rank sum test). The reduction in mast cell counts was independent of the degree of inflammation or architectural distortion. There was a negative correlation between the dose of corticosteroids and mast cell count (r = 0.53, P less than 0.05 Spearman rank correlation), and the mast cell count was reduced within a few days of treatment and remained low throughout steroid therapy. Mucosal mast cell depletion may be an important mechanism of action of corticosteroids in inflammatory bowel disease.

Prolonged treatment with topical glucocorticoids results in an inhibition of the allergen-induced weal-and-flare response and a reduction in skin mast cell numbers and histamine content

The inhibitory effects of topical glucocorticosteroid treatment on the immediate dermal allergic reaction were studied in 10 patients in a double, randomized, placebo-controlled fashion. The aim was to study whether a prolongation of the treatment time would enhance the inhibitory effect beyond the 30-40% reduction previously reported after 1 week of treatment, and whether any changes in skin reactivity were accompanied by changes in the level of mast cells or histamine at the challenge site. Allergen and histamine skin-prick tests were performed on both forearms before the start of the study and after 2 and 4 weeks of treatment with placebo cream on one forearm and with 0.05% clobetasol-17-propionate cream on the other. Punch biopsies from the skin treated actively and with placebo were taken after 4 weeks in eight of the patients. The specimens were used for the light-microscopic evaluation of mast cell density and for the measurement of histamine and protein content. After 4 weeks of treatment we found a reduction in the allergen-induced weal (72%; P less than 0.001) and flare (62%; P less than 0.05) response. There was also a minor reduction in the histamine-induced weal (38%; P less than 0.05) but not the flare response, suggesting that the glucocorticoid treatment induced a reduced mediator release at allergen challenge. This could be partially explained by the finding of a reduction in the number of detectable skin mast cells (85%; from 0.78 to 0.11 mast cells per unit area) and in the histamine content of the skin as related to the tissue wet weight (36%; P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

The cellular response of the human allergic mucosa to natural allergen exposure

It has been suggested that the IgE-dependent late-phase reaction to allergen exposure, with the features of an inflammatory cellular infiltration and airway hyperreactivity, is a link between anaphylaxis and continuous allergic airway disease. Our main knowledge of the cellular response to allergen in sensitized individuals has been derived from allergen-challenge models. To explore the dynamics of the cellular response during the actual disease, patients with a strictly seasonal allergic rhinitis were studied during natural allergen exposure. Ten patients suffering from an isolated birch-pollen allergy were followed from a symptom-free state before, during, and to the height of the birch-pollen season. Repeated parallel cell samplings from the nasal mucosa were performed with cytologic imprints on plastic strips, nasal lavages with the recovery of the cells in the lavage fluid with cytocentrifugation on object slides for cytologic study, and scrapings from the nasal surface with a curette for histologic and ultrastructural evaluation. The histamine content was determined in lavage fluid and cell pellets. The tosyl-alpha-tosyl-L-arginine methyl esterase activity of the nasal lavage fluid was also determined as a biochemical marker of the allergic inflammatory reaction. The birch-pollen season was moderate in terms of pollen counts, and this resulted in mild to moderate nasal symptoms that ran parallel to the birch-pollen counts. The total number of cells recovered in the lavage fluid was 1.2 +/- 0.4 (SEM) x 10(6) before and 3.2 +/- 2.0 per 10(6) cells (not significant) during pollen exposure. Most cells were neutrophils and mononuclear cells.(ABSTRACT TRUNCATED AT 250 WORDS)