Characterization of oral immune cells in birch pollen-allergic patients: impact of the oral allergy syndrome and sublingual allergen immunotherapy on antigen-presenting cells.

BACKGROUND: A detailed characterization of human oral immune cells is needed to better understand local mechanisms associated with allergen capture following oral exposure. METHODS: Oral immune cells were characterized by immunohistology and immunofluorescence in biopsies obtained from three healthy individuals and 23 birch pollen-allergic patients with/without oral allergy syndrome (OAS), at baseline and after 5 months of sublingual allergen immunotherapy (AIT). RESULTS: Similar cell subsets (i.e., dendritic cells, mast cells, and T lymphocytes) were detected in oral tissues from healthy and birch pollen-allergic individuals. CD207+ Langerhans cells (LCs) and CD11c+ myeloid dendritic cells (DCs) were found in both the epithelium and the papillary layer of the Lamina propria (LP), whereas CD68+ macrophages, CD117+ mast cells, and CD4+ /CD8+ T cells were rather located in both the papillary and reticular layers of the LP. Patterns of oral immune cells were identical in patients with/without OAS, except lower numbers of CD207+ LCs found in oral tissues from patients with OAS, when compared to OAS- patients (P < 0.05). A 5-month sublingual AIT had a limited impact on oral immune cells, with only a significant increase in IgE+ cells in patients from the active group. Colocalization experiments confirmed that such IgE-expressing cells mostly encompass CD68+ macrophages located in the LP, and to a lesser extent CD207+ LCs in the epithelium. CONCLUSION: Two cell subsets contribute to antigen/allergen uptake in human oral tissues, including (i) CD207+ LCs possibly involved in the physiopathology of OAS and (ii) CD68+ macrophages likely critical in allergen capture via IgE-facilitated mechanisms during sublingual AIT.

Development and evaluation of a sublingual tablet based on recombinant Bet v 1 in birch pollen-allergic patients.

BACKGROUND: Sublingual immunotherapy (SLIT) applied to type I respiratory allergies is commonly performed with natural allergen extracts. Herein, we developed a sublingual tablet made of pharmaceutical-grade recombinant Bet v 1.0101 (rBet v 1) and investigated its clinical safety and efficacy in birch pollen (BP)-allergic patients. METHODS: Following expression in Escherichia coli and purification, rBet v 1 was characterized using chromatography, capillary electrophoresis, circular dichroism, mass spectrometry and crystallography. Safety and efficacy of rBet v 1 formulated as a sublingual tablet were assessed in a multicentre, double-blind, placebo-controlled study conducted in 483 patients with BP-induced rhinoconjunctivitis. RESULTS: In-depth characterization confirmed the intact product structure and high purity of GMP-grade rBet v 1. The crystal structure resolved at 1.2 Å documented the natural conformation of the molecule. Native or oxidized forms of rBet v 1 did not induce the production of any proinflammatory cytokine by blood dendritic cells or mononuclear cells. Bet v 1 tablets were well tolerated by patients, consistent with the known safety profile of SLIT. The average adjusted symptom scores were significantly decreased relative to placebo in patients receiving once daily for 5 months rBet v 1 tablets, with a mean difference of 17.0-17.7% relative to the group treated with placebo (P < 0.025), without any influence of the dose in the range (12.5-50 µg) tested. CONCLUSION: Recombinant Bet v 1 has been produced as a well-characterized pharmaceutical-grade biological drug. Sublingual administration of rBet v 1 tablets is safe and efficacious in patients with BP allergic rhinoconjunctivitis.

Recommendations for the standardization of clinical outcomes used in allergen immunotherapy trials for allergic rhinoconjunctivitis: an EAACI Position Paper.

BACKGROUND: Allergen immunotherapy (AIT) has been thoroughly documented in randomized controlled trials (RCTs). It is the only immune-modifying and causal treatment available for patients suffering from IgE-mediated diseases such as allergic rhinoconjunctivitis, allergic asthma and insect sting allergy. However, there is a high degree of clinical and methodological heterogeneity among the endpoints in clinical studies on AIT, for both subcutaneous and sublingual immunotherapy (SCIT and SLIT). At present, there are no commonly accepted standards for defining the optimal outcome parameters to be used for both primary and secondary endpoints. METHODS: As elaborated by a Task Force (TF) of the European Academy of Allergy and Clinical Immunology (EAACI) Immunotherapy Interest Group, this Position Paper evaluates the currently used outcome parameters in different RCTs and also aims to provide recommendations for the optimal endpoints in future AIT trials for allergic rhinoconjunctivitis. RESULTS: Based on a thorough literature review, the TF members have outlined recommendations for nine domains of clinical outcome measures. As the primary outcome, the TF recommends a homogeneous combined symptom and medication score (CSMS) as a simple and standardized method that balances both symptoms and the need for antiallergic medication in an equally weighted manner. All outcomes, grouped into nine domains, are reviewed. CONCLUSION: A standardized and globally harmonized method for analysing the clinical efficacy of AIT products in RCTs is required. The EAACI TF highlights the CSMS as the primary endpoint for future RCTs in AIT for allergic rhinoconjunctivitis.

Efficacy, safety, and immunological effects of a 2-year immunotherapy with Depigoid birch pollen extract: a randomized, double-blind, placebo-controlled study.

BACKGROUND: Rhinoconjunctivitis due to birch pollen sensitization is common in Northern Europe. A depigmented polymerized birch pollen extract - Depigoid has been developed for immunotherapy. OBJECTIVE: To evaluate its clinical efficacy, safety, and effects on immunological parameters. METHODS: Sixty-one patients aged 7-69 years were included in a randomized, double-blind, placebo-controlled trial of subcutaneous immunotherapy (SCIT) using depigmented polymerized birch pollen extract. SCIT consisted of four increasing doses at 7-day intervals, followed by maintenance injections of 500 DPP (corresponding to 30 microg Bet v1 before depigmentation) at 6-week intervals for 18 months. The primary outcome was the combined symptom and medication score during the 2006 birch pollen season. The frequency of peripheral blood mononuclear cells (PBMC)producing IL-4, IL-10, IL-12, and IL-13 was assessed in a subgroup of patients by ELISPOT assay. RESULTS: After 18 months of treatment, the median combined symptom and medication score (upper/lower quartile) of treated patients was significantly lower than those on placebo: 8.0 (5.8-10.3) and 12.6 (8.6-16.2), respectively (P=0.004). Systemic reactions occurred in 29 patients (12 active, 17 placebo), were grades 1 or 2, and none required specific treatment. After 18 months of treatment, mean serum concentrations of specific IgE increased significantly in both groups (P<0.0001) whereas serum concentrations of both specific IgG1 and IgG4 only increased significantly in the SCIT group (P=0.002) and not in the placebo group. The seasonal increase in numbers of IL-4- and IL-13-producing PBMC was blunted by immunotherapy. CONCLUSIONS: SCIT with depigmented polymerized birch pollen extract significantly reduced symptom and medication scores when compared with the placebo, was well tolerated, and resulted in immunological changes comparable with those of native pollen extracts.

A follow-up study of immunotherapy-treated birch-allergic patients: effect on the expression of chemokines in the nasal mucosa.

BACKGROUND: Specific immunotherapy (SIT) is the only treatment producing lasting clinical improvement in patients with allergy. We investigated the long-term effect of SIT treatment on the expression of chemokines: eotaxin, RANTES (regulated upon activation, normal T cell expressed and secreted) and thymus and activation-regulated chemokine (TARC), and their receptors CCR3 and CCR4 in biopsies of nasal mucosa from birch-allergic individuals. METHODS: Sixteen patients who completed a 3-year treatment programme 3-5 years ago, and 12 untreated, matched controls were included in the study. Patients recorded symptoms and use of rescue medication before and during the pollen season. Nasal mucosa samples obtained before and during the season were stained for eosinophil and mast cell markers and for eotaxin, RANTES, TARC, CCR3 and CCR4. RESULTS: During the pollen season, rhinoconjunctivitis symptoms increased in both SIT and control groups (P=0.001 and 0.002, respectively). However, SIT patients had 37% fewer symptoms than controls. Medication use increased in both groups (P=0.002) during the season but the SIT group used 28% less than the controls (P=0.02). The number of eosinophils in the nasal mucosa increased in the control group (P=0.01) and the difference between the groups was significant during the season (P=0.01). No seasonal increase in the numbers of mast cells was seen, but during the pollen season, more (P=0.02) AA(+) cells were found in the controls than in the SIT group. The number of eotaxin(+) and RANTES(+) cells increased in the control group (P=0.01 and 0.03, respectively) and the difference between groups during the season was significant (P=0.01 and 0.01, respectively). The TARC(+) cell numbers were lower in the SIT group during the season (P=0.003). The CCR3(+) cells increased only in the control group during the pollen season and remained unchanged in SIT patients, while CCR4(+) cell numbers increased in both the control (P=0.03) and SIT (P=0.02) groups. CONCLUSION: This study confirmed that decreased numbers of eosinophils in the nasal mucosa is a long-lasting effect of birch SIT. SIT also prevented seasonal rises in the number of cells expressing the chemokines eotaxin and RANTES.

A double-blind placebo-controlled birch allergy vaccination study II: correlation between inhibition of IgE binding, histamine release and facilitated allergen presentation.

BACKGROUND: The pathogenesis of IgE-mediated allergic disease is closely related to the production of T-helper type 2 (Th2) cytokines, which lead to IgE production pivotal for activation of mast cells and basophils. Proliferating T cells along with eosinophils expanded and attracted by Th2 cytokines are major contributors to the late-phase reaction. The activation of these Th2 cells is strongly enhanced by CD23-mediated IgE facilitated allergen presentation (FAP). OBJECTIVE: The present study aims to investigate the effect of specific immunotherapy (SIT)-induced allergen-specific non-IgE antibodies (blocking antibodies) on IgE binding to allergen, histamine release (HR) and CD23-mediated allergen uptake in antigen-presenting cells. METHODS: Competition between IgE and non-IgE for allergen binding was studied by Advia Centaur antibody measurements, passively sensitized basophils were used to study HR and IgE-facilitated binding of allergen to B cells (FAP) was studied by flow cytometry. FAP measurements were performed both with and without the addition of a reference IgE serum, which was included to obtain optimal complex formation. The serum samples were obtained from birch pollen immunotherapy (n=21) or placebo control patients (n=21) before and after 1 and 2 years of treatment. RESULTS: Statistically significant reduction of all parameters investigated was observed after 1 year of treatment and the effect was maintained during the second year of treatment. There was a clear correlation between the two FAP measurements and between each of them and the level of T cell activation reported upon previously. Moreover, strong correlations were found between changes in FAP, IgE binding and HR. CONCLUSION: The present study clearly demonstrates that SIT induces changes in the composition of serum antibodies that inhibit IgE binding, HR and FAP to a similar extent. This suggests that these measurements, individually or in combination, may be used to monitor the immunological effect of SIT, even though direct correlations to changes in clinical parameters could not be demonstrated.

The CREATE project: development of certified reference materials for allergenic products and validation of methods for their quantification.

Allergen extracts have been used for diagnosis and treatment of allergy for around 100 years. During the second half of 20th century, the notion increasingly gained foothold that accurate standardization of such extracts is of great importance for improvement of their quality. As a consequence, manufacturers have implemented extensive protocols for standardization and quality control. These protocols have overall IgE-binding potencies as their focus. Unfortunately, each company is using their own in-house reference materials and their own unique units to express potencies. This does not facilitate comparison of different products. During the last decades, most major allergens of relevant allergen sources have been identified and it has been established that effective immunotherapy requires certain minimum quantities of these allergens to be present in the administered maintenance dose. Therefore, the idea developed to introduce major allergens measurements into standardization protocols. Such protocols based on mass units of major allergen, quantify the active ingredients of the treatment and will at the same time allow comparison of competitor products. In 2001, an EU funded project, the CREATE project, was started to support introduction of major allergen based standardization. The aim of the project was to evaluate the use of recombinant allergens as reference materials and of ELISA assays for major allergen measurements. This paper gives an overview of the achievements of the CREATE project.

[Comparison of in vitro and in vivo methods of evaluation of the efficacy of influenza virus hemagglutinin inhibitors].

One of the problem in the selection of the most effective antiviral preparations with a broad spectrum of antiviral protective activity, is the "continuity" of assays of different level of complexity so, that the most effective antiviral therapeutic, selected by in vitro assays would be the most effective in vivo. Comparative study of the efficacy of the influenza virus inhibitor in the assays of inhibition of virus binding with fetuin, inhibition of infectious focus forming units in MDCK cells, inhibition of virus yield in infected MDCK cells, and inhibition of influenza virus infectivity in mice infected by viral aerosol are presented. The value of 50% inhibiting concentration IC50 for the pare "influenza virus strain A/NIB/23/89-MA-inhibitor tetra-Aca6-6'SLN" corresponded to 6-10 microM and was invariant for three different tests--in vitro assay of inhibition of virus binding with fetuin, inhibition of yield in infected MDCK cell culture, and inhibition of virus infectivity in mice, but not for the assay of inhibition of infectious focus forming units in cell culture.

Chromosomal assignment of 20 candidate genes for canine congenital sensorineural deafness by FISH and RH mapping.

The analysis of inherited diseases in the domestic dog (Canis familiaris) provides a resource for the continued use of this species as a model system for human diseases. Many different dog breeds are affected by congenital sensorineural deafness. Since mutations in various genes have already been found causative for sensorineural hearing impairment in humans or mice, 20 of these genes were considered as candidates for deafness in dogs. For each of the candidate genes a canine BAC clone was isolated by screening with heterologous human or murine cDNA probes. The gene-containing BAC clones were physically assigned to the canine genome by FISH and the BAC-derived STS-markers were positioned with the RHDF5000 panel on the canine RH map. The mapping data, which confirm the established conservation of synteny between canine and human chromosomes, provide a resource for further association studies in segregating canine populations and the basis for new insights into this common canine and human disease.

Allergen induced cytokine profiles in type I allergic individuals before and after immunotherapy.

Allergen immunotherapy (IT) involves subcutaneous injections of increasing doses of specific allergen over a period of time. It is recognised as highly effective in the treatment of patients with allergic rhinitis. However, the specific immunological mechanisms by which IT achieves its effect have not been fully elucidated. Recent studies, have shown that the clinical effects following IT of allergic individuals is concomitant with a reduced production of IL-4 by allergen specific CD4+ T-cells. The aim of the present study was to gain better knowledge about the immunological mechanisms by which IT exerts its beneficial effects. For this purpose, peripheral blood mononuclear cells (PBMC) from ten individuals receiving birch allergen or placebo in an IT-study performed in a double-blind manner, were analysed for IL-4, IFN-gamma, IL-5 and IL-10 mRNA expression at the onset of the study and during the pollen season, during treatment. Both spontaneous and in vitro allergen-induced cytokine mRNA expression was analysed using reverse transcriptase-polymerase chain reaction (RT-PCR). Spontaneous expression of IL-4 mRNA could be detected in most of the allergic patients, but not in healthy donors. The IT-treated patients showed a decrease in the spontaneous expression of IL-4 mRNA during the pollen season as compared to at the onset of the study, while in patients receiving placebo the IL-4 mRNA expression increased or remained unchanged. Similar results were obtained after in vitro stimulation with allergen. This was in contrast to the results for IFN-gamma, which was readily detected in both patient groups with no significant differences between the groups at either timepoint. IL-5 was shown to be increased during the pollen season in both groups and thereby presumably not affected by allergen IT. Taken together, these observations suggest that the cytokine profiles in circulating T lymphocytes change as a consequence of allergen IT.

Comparable effects of inhaled fluticasone propionate and budesonide on the HPA-axis in adult asthmatic patients.

This randomized, double-blind, double-dummy, multicentre cross-over study compared the effects on the hypothalamic-pituitary-adrenal (HPA) axis of fluticasone propionate (750 microg twice daily given via the Diskus) and budesonide (800 microg twice daily given via the Turbuhaler). Two treatment periods of 2 weeks each were preceded by a 2-week run-in period and separated by a 2-week washout period. During run-in and washout, patients received beclomethasone dipropionate (BDP) or budesonide at a constant dose of 1500-1600 microg day(-1). Sixty patients aged 18-75 years with moderate to severe asthma not fully controlled by treatment with 1500-1600 microg day(-1) budesonide or BDP entered run-in and 45 completed the study. HPA axis suppression was assessed by morning serum cortisol (area under the curve from 08.00 to 10.30 hours) and 12-h nocturnal urinary cortisol excretion, measured at the end of run-in (baseline 1), at the end of washout (baseline 2), and at the end of each treatment period. Neither budesonide nor fluticasone produced significant suppression of either parameter compared to baselines. Only a few patients had serum-cortisol and urinary cortisol values below the normal range, before and after treatment. This shows that the patients did not have adrenal suppression before entering the study. The ratio between the AUC serum cortisol measured after fluticasone treatment and after budesonide treatment was 0.99 (95% CI 0.92-1.06), indicating equivalent effects on the HPA axis. This result was achieved after having omitted two patients' results, due to their very sensitive reaction to budesonide, but not to fluticasone. Two exacerbations of acute asthma occurred during budesonide treatment and none during fluticasone treatment. Both treatments were well tolerated. In conclusion, budesonide 1600 microg day(-1) via Turbuhaler and fluticasone propionate 1500 microg day(-1) via Diskus had no clinical effects on the HPA axis in patients with moderate to severe asthma.

Ambient level of NO2 augments the inflammatory response to inhaled allergen in asthmatics.

Air pollution constitutes an important factor for asthma aggravation, and there is increased concern about respiratory health effects of common air pollutants. The purpose of this study was to examine how exposure to a high ambient concentration nitrogen dioxide (NO2) prior to a bronchial allergen challenge modulated the inflammatory response in the bronchi. Thirteen subjects with mild asthma and allergy were exposed at rest to either purified air or 500 microg x m 3 NO2 for 30 min, followed 4 h later by an allergen inhalation challenge. The exposures (NO2 or air) were performed in random order and at least 4 weeks apart. Lung function during NO2/air exposure and allergen challenge was measured by plethysmography, and then hourly by portable spirometry after exposures. Subjective symptoms were recorded during and after exposure. Bronchoscopy with bronchial wash (BW) and bronchoalveolar lavage (BAL) was performed 19 h after allergen challenge. NO2+allergen enhanced the percentage of neutrophils in both BW and BAL compared to air+allergen (BW 19 vs. 11, P=0.05; BAL 3 vs. 1, P=0.02 median values). The levels of eosinophil cationic protein (ECP) in BW was higher after NO2+allergen compared to air+allergen (90 vs. 3.6 microg/l; P=0.02, median values). There was no NO2-associated effect on symptoms or pulmonary function. These data suggest that ambient NO2 can enhance allergic inflammatory reaction in the airways without causing symptoms or pulmonary dysfunction.

Living & learning with allergy: a European perception study on respiratory allergic disorders.

BACKGROUND: Knowledge of allergy patients' perception of own disease is inadequate, and understanding of the impact of local environment, including family and health-care system, on patients' management of disease is insufficient. We examined the potential of telephone-based survey techniques for establishing this knowledge in 10 European countries. METHODS: A two-phased questionnaire developed by use of focus groups in seven countries was translated into 10 languages. To ensure that the true values of the populations were restored in randomly selected populations, 75,343 telephone numbers selected for screening represented balanced national distributions of households. RESULTS: Eight thousand two hundred and sixty-eight respiratory allergy sufferers were identified by the telephone screening process. 85.4% accepted to participate in the survey and 89.6% completed both phases comprising 34 questions and rating of 49 statements. Data for each country were weighted in terms of age, sex and the recorded allergy prevalence within age intervals. CONCLUSIONS: The telephone survey technique allowed for establishment of random representative samples, and application of mathematical weighting procedures assured that the true national values were restored in the data set. As all interviews were performed in a standardised manner we conclude that the telephone-based survey methodology enables national representative data set to be established and compared.

Is the Horaana strain of the Culex pipiens group Culex pipiens pallens?

The validity of the Horaana strain of the Culex pipiens group as Cx. pipiens pallens was studied. Judging from the fourth instar characters and morphology of the adult male genitalia, this laboratory strain is now out of the range of ordinary Cx.p. pallens in Japan, and must be identified as Cx. p. quinquefasciatus.

Early and late phase asthmatic response in lower airways of cat-allergic asthmatic patients--a comparison between experimental and environmental allergen challenge.

BACKGROUND: Standardized experimental allergen challenges are usually adopted to investigate the effect of allergen exposure on the lower airways. Environmental (natural) allergen challenges are used less often, mainly because of difficulties in standardizing the method, safety reasons and costs. The aim of this study was to investigate the relationship between an experimental and an environmental bronchial challenge. For this reason a natural challenge model was developed. METHODS: Sixty-two patients with a history of cat allergen-induced symptoms involving the lower airways, positive skin prick test, positive in vitro specific IgE to cat allergen and bronchial hyper-responsiveness were included. All 62 patients underwent an experimental challenge in the laboratory followed by an environmental allergen challenge. RESULTS: All 62 patients developed an early asthmatic response [>or=20% fall in forced expiratory volume in 1 s (FEV1)] in the experimental challenge and 60% (37/62) during the environmental challenge. A late asthmatic response (>or=15% fall in FEV1 within 3-24 h) was seen in 56% (35/62) of the patients after the experimental challenge. Following the environmental challenge 47% (29/62) of the patients developed a late response. Thirty-four per cent (21/62) of the patients developed a late response in both challenge models and 31% (19/62) did not develop a late response in any model. Thus, there was consistency in 65% (40/62) of the patients in both challenge models. CONCLUSION: We found consistency in the pattern of response to inhaled allergen between the two challenge models and we believe that experimental bronchial challenge is likely to reflect the development of relevant inflammation in the lower airways after low-dose allergen exposure in the environment.

Specific immunotherapy with SQ standardized grass allergen tablets in asthmatics with rhinoconjunctivitis.

BACKGROUND: The best way to prevent allergy symptoms is to treat the allergic condition. Specific immunotherapy with grass allergen tablets 75,000 SQ-T (Grazax, Phleum pratense, ALK-Abelló) is safe and efficacious in rhinoconjunctivitis patients. As rhinoconjunctivitis often co-exists with asthma, we aimed to confirm safety and efficacy in grass allergic subjects with asthma and rhinoconjunctivitis. METHODS: A randomized, double-blind, placebo-controlled, multicentre trial was performed 10-14 weeks prior to and during the grass pollen season 2004. About 114 subjects were randomized 2 : 1 to grass allergen tablets or placebo. The primary end points were average asthma medication and symptom scores during the grass pollen season, and secondary variables were average rhinoconjunctivitis symptom and medication scores during the grass pollen season. Additionally, number of well days was defined post hoc. RESULTS: Differences in asthma medication and symptom scores between the treatment groups were negligible. The mean difference in asthma medication score was below 0.1 and 0.3 for asthma symptom score [a single inhalation of salbutamol (200 microg) was scored 2]. No serious adverse events were reported. A reduction in rhinoconjunctivitis symptom score of 37% (P = 0.004) and a 41% (P = 0.036) reduction in medication score was found in the grass pollen season for subjects treated with the grass allergen tablet compared with placebo. Well days increased by 54% (P = 0.002). CONCLUSIONS: Self-administration of the grass allergen tablet was safe. The treatment did not impair asthma control and confirmed considerable symptom prevention and reduced medication use. It addresses the allergic condition and represents a baseline treatment for grass pollen allergy.

Increased expression of lipoxygenase enzymes during pollen season in nasal biopsies of pollen-allergic patients.

BACKGROUND: Exposure of patients sensitized to pollen triggers development of seasonal allergic rhinitis symptoms (SAR). Eicosanoids are a group of arachidonic acid metabolites contributing to the symptoms of SAR. The aim of this study was to investigate seasonal changes in the expression of enzymes of the eicosanoid pathway in the nasal mucosa of patients with SAR. METHODS: Twenty SAR patients allergic to birch or grass and eight healthy subjects were included in the study. Patients registered rhinoconjunctivitis symptoms and use of rescue medication before and during the pollen season. Nasal biopsies were obtained before and around the peak of the season, sectioned and stained using markers for eosinophils, mast cells, T cells and neutrophils. Antibodies against the following enzymes were also used: cyclo-oxygenase (COX-1, COX-2), 5-lipoxygenase (5-LO), 5-lipoxygenase-activating factor (FLAP), LTA4 hydrolase (LTA4h) and LTC4 synthase (LTC4s). RESULTS: During the pollen season symptoms of rhinoconjunctivitis and medication score increased significantly (P=0.001; P=0.001 respectively). During the pollen season numbers of eosinophils (P=0.02) and cell positive 5-LO (P=0.02), LTC4s (P=0.04) and LTA4h (P=0.02) increased significantly. During season number of mast cells and cells expressing 5-LO and LTA4h were higher in SAR than in healthy controls group (P=0.02; P=0.01; P=0.03 respectively). CONCLUSION: In sensitized patients exposure to pollen allergen results in increased expression of enzymes of the eicosanoid pathway.