Ragweed Pollen Extract Research Articles

Inhibition of Aldose Reductase Prevents Experimental Allergic Airway Inflammation in Mice

BackgroundThe bronchial asthma, a clinical complication of persistent inflammation of the airway and subsequent airway hyper-responsiveness, is a leading cause of morbidity and mortality in critically ill patients. Several studies have shown that oxidative stress plays a key role in initiation as well as amplification of inflammation in airways. However, still there are no good anti-oxidant strategies available for therapeutic intervention in asthma pathogenesis. Most recent studies suggest that polyol pathway enzyme, aldose reductase (AR), contributes to the pathogenesis of oxidative stress–induced inflammation by affecting the NF-κB-dependent expression of cytokines and chemokines and therefore inhibitors of AR could be anti-inflammatory. Since inhibitors of AR have already gone through phase-III clinical studies for diabetic complications and found to be safe, our hypothesis is that AR inhibitors could be novel therapeutic drugs for the prevention and treatment of asthma. Hence, we investigated the efficacy of AR inhibition in the prevention of allergic responses to a common natural airborne allergen, ragweed pollen that leads to airway inflammation and hyper-responsiveness in a murine model of asthma.Methods and FindingsPrimary Human Small Airway Epithelial Cells (SAEC) were used to investigate the in vitro effects of AR inhibition on ragweed pollen extract (RWE)-induced cytotoxic and inflammatory signals. Our results indicate that inhibition of AR prevents RWE -induced apoptotic cell death as measured by annexin-v staining, increase in the activation of NF-κB and expression of inflammatory markers such as inducible nitric oxide synthase (iNOS), cycloxygenase (COX)-2, Prostaglandin (PG) E2, IL-6 and IL-8. Further, BALB/c mice were sensitized with endotoxin-free RWE in the absence and presence of AR inhibitor and followed by evaluation of perivascular and peribronchial inflammation, mucin production, eosinophils infiltration and airway hyperresponsiveness. Our results indicate that inhibition of AR prevents airway inflammation and production of inflammatory cytokines, accumulation of eosinophils in airways and sub-epithelial regions, mucin production in the bronchoalveolar lavage fluid and airway hyperresponsiveness in mice.ConclusionsThese results suggest that airway inflammation due to allergic response to RWE, which subsequently activates oxidative stress-induced expression of inflammatory cytokines via NF-κB-dependent mechanism, could be prevented by AR inhibitors. Therefore, inhibition of AR could have clinical implications, especially for the treatment of airway inflammation, a major cause of asthma pathogenesis.

Sensibilisierung gegen Ambrosiapollen – Eine Ursache für allergische Atemwegserkrankungen in Deutschland?

Allergic skin and respiratory diseases show a high prevalence in most industrial countries. In addition, during the last years ragweed colonization has increased in Europe. Ambrosia pollen ( AMBROSIA ARTEMISIIFOLIA L. - common ragweed) are highly allergenic. Due to the late flowering time (august/September) of ragweed this can result in increasing health threats for allergic populations. This is of particular importance for those who already are sensitive to some grass or tree pollen. These individuals can then suffer from allergies during nearly the whole year. The present study examined the prevalence of sensitization to ragweed in German children and possible health implications. Between 2004 and 2007 sera of 1323 10-years old children in Baden Württemberg were tested in-vitro for specific IgE-antibodies against common aeroallergens including ragweed pollen. Specific IgE-antibodies to extracts of common ragweed pollen were present in 10 - 17 % of the tested sera depending on the year of investigation. The determined specific IgE-antibodies may be the result of a direct sensitization to ragweed pollen or correspond to cross-reactivity to other plants of the asteraceae subfamily or some nutritional allergens. The detection of sensitization to ragweed pollen does not prove actual allergic disease. However, a ragweed derived allergy should be considered in the differential diagnosis when allergic symptoms are present in direct connection to the flowering-time of ragweed. Ragweed plants should be removed and the spread of the plant 'restricted', as experiences in other countries with already wide spreading show.

Ragweed pollen-mediated IgE-independent release of biogenic amines from mast cells via induction of mitochondrial dysfunction

Normal functions of mitochondria are required for physiological dynamics of cells, while their dysfunction contributes to development of various disorders including those of immune system. Here we demonstrate that exposure of mast cells to ragweed pollen extract increases production of H 2O 2 via mitochondrial respiratory complex III. These mitochondrial ROS (mtROS) enhance secretion of histamine and serotonin from mast cells, but not enzymes such as β-hexosaminidase, independently from FcɛRI-generated stimuli. The release of biogenic amines is associated with inhibition of secretory granules’ H +-ATPase activity, activation of PKC-δ and microtubule-dependent motility, and it is independent from intracellular free Ca 2+ levels. To asses differences from IgE-mediated mast cell degranulation we show that mtROS decrease antigen-triggered β-hexosaminidase release, while they are synergistic with antigen-induced IL-4 production in sensitized cells. Taken together, these data indicate that mitochondrial dysfunction can act independently from adaptive immunity, as well as augments Th2-type responses. Pharmacological maintenance of physiological mitochondrial function could have clinical benefits in prevention and treatment of allergic diseases.

Hay Fever Symptoms, Blocking Antibody Levels, and Leucocyte Histamine Release in Patients Receiving Very High Dosage Immunotherapy with Ragweed Pollen Extract

Hay Fever Symptoms, Blocking Antibody Levels, and Leucocyte Histamine Release in Patients Receiving Very High Dosage Immunotherapy with Ragweed Pollen Extract

Oxidative Damage to Mitochondrial Respiratory Chain Complexes Increases Allergic Airway Inflammation in Mice

RATIONALE: It has been shown that NAD(P) H oxidase in ragweed pollen extracts (RWE) generates oxidative stress in the airway epithelium and this oxidative insult is essential for the robust antigen-driven airway inflammation. In this study we aimed to determine whether mitochondrial respiratory chain (MRC) proteins were oxidatively damaged by ROS generated by pollen NAD(P) H oxidases and if this damage could exacerbate allergic airway inflammation.

Sublingual-oral administration of standardized allergenic extracts: phase 1 safety and dosing results

European studies provide a preponderance of evidence for sublingual allergen immunotherapy (SLIT) safety and efficacy, but they use allergen products that differ from those expected to be approved in the United States. To determine the safety and tolerability of 4 US-licensed standardized SLIT allergenic extracts. Adults 18 to 50 years old with allergic rhinitis with or without asthma due to timothy grass pollen, short ragweed pollen, house dust mite, or cat hair allergy completed a single-session dose escalation followed by an 8-week, open-label daily course of SLIT. Participants documented the presence and severity of adverse effects and adherence using a daily electronic diary. Ninety-one participants initiated treatment, and 77 completed the phase 1 testing. Maximum tolerable doses ranged from 50 to 2,090 BAU for cat hair and dust mite extract, 31 to 91 Amb a 1 Units for short ragweed pollen extract, and 50 to 21,090 BAU for timothy grass pollen extract. During the 8-week treatment course, 98.9% of participants reported at least 1 mild, 70.4% at least 1 moderate, and 13.6% at least 1 severe adverse effect. Most adverse effects (94.6%) were rated as mild, 5.2% as moderate, and 0.1% as severe; nasal and oral-mucosal adverse effects were most commonly reported. No life-threatening adverse reactions occurred in more than 4,500 administered doses. Daily sublingual-oral dosing of standardized allergenic extracts at maximum tolerable doses was generally well tolerated. These results are a first step toward establishing the safety of US-licensed SLIT extracts when appropriately self-administered and monitored.

Prevalence of IgE-Binding to Art v 1, Art v 4 and Amb a 1 in Mugwort-Allergic Patients

Background: Mugwort (Artemisia vulgaris) represents an important source of weed pollen allergens. The objectives of the present study were (i) to analyze the IgE binding profiles in a group of mugwort-allergic patients, (ii) to identify individual marker allergens crucial for the diagnosis of mugwort allergy and (iii) to identify potential crossreactive allergens present in ragweed (Ambrosia artemisiifolia) pollen extract. Methods: Sera from 100 pediatric mugwort-allergic patients were analyzed for their IgE binding pattern to natural mugwort and ragweed pollen proteins, purified natural and recombinant Art v 1, recombinant Art v 4 and recombinant Amb a 1 using immunoblots and ELISA. Results: 91% of the patients’ sera tested displayed IgE binding to one or more mugwort pollen allergens in ELISA and 88% were positive in immunoblot. Purified natural Art v 1 was recognized by 79%, the recombinant protein by 39% of the patients tested and purified recombinant Art v 4 by 34% of the patients’ sera. 67% of the sera displayed crossreactive IgE to one or more ragweed pollen allergens. Recombinant Amb a 1 was noted in only 14% of the mugwort-allergic sera. Conclusions: Allergen-specific in vitro diagnosis was performed in 100 pediatric mugwort-allergic serum samples. Using two allergens (Art v 1 and Art v 4), 91% of the patients could be identified as mugwort pollen-sensitized patients by IgE in vitro tests. Crossreactivity to ragweed pollen allergens was demonstrated by in vitro experiments, suggesting a new important and potent allergen source expanding across Europe.

Immunologic analysis of monoclonal and immunoglobulin E antibody epitopes on natural and recombinant Amb a 1

Amb a 1 is the major allergen from ragweed pollen and more than 90% of ragweed-allergic patients react with this protein. Although Amb a 1 was cloned and sequenced in 1991, little is known of the specificity of anti-Amb a 1 antibodies or of the immunologic properties of the recombinant allergen. To compare binding of monoclonal antibodies (mAb) and IgE antibodies to purified natural Amb a 1 (nAmb a 1) and recombinant Amb a 1 (rAmb a 1). Binding of a panel of anti-Amb a 1 mAb and IgE antibodies to nAmb a 1 or rAmb a 1 was compared by immunoblotting. Chimeric ELISA was used to measure specific IgE to these allergens using 89 ragweed-allergic sera from Austria, Italy, Canada and the United States. The 8 mAb bound to a 38 kDa Amb a 1 band in ragweed pollen extract and a subset of 5 mAb also bound to the 26 kDa chain of nAmb a 1. A two-site ELISA was developed using a mAb pair, which was approximately 10-fold more sensitive to rAmb a 1. There was a significant correlation between IgE antibody binding to nAmb a 1 and rAmb a 1 (n=89, r=0.79, P<0.001). A subset of approximately 40% of patients showed greater reactivity to nAmb a 1 than to rAmb a 1. The data suggest that there is less reactivity of human IgE to rAmb a 1 compared with nAmb a 1. The development of more sensitive, quantitative ELISA for Amb a 1 will require the production of new mAb especially directed against nAmb a 1.

Immunoreactivity profile of peripheral blood mononuclear cells from patients with ragweed‐induced allergic rhinitis

Seasonal rhinitis is manifested by a series of nasal symptoms in response to exposure to seasonal allergens including ragweed pollen. Understanding its immunological mechanisms may help to better manage the disease. We sought to determine comprehensively ragweed-induced cytokine and chemokine production by peripheral blood mononuclear cells from normal individuals and patients with seasonal rhinitis sensitized to ragweed pollen, and to assess its regulation by exogenous IL-10. Cells were cultured in the presence or absence of a purified ragweed pollen extract with or without exogenous IL-10. Cytokines and chemokines were measured in the supernatant. Gene expression was evaluated using real-time quantitative reverse transcription PCR. Ragweed stimulation significantly increased the production of the Th2-associated cytokines IL-5, IL-9 and IL-13, the chemokines CCL17 and CCL22 and the regulatory cytokine IL-10 in allergic patients, whereas transforming growth factor-beta (TGF-beta) production was increased only in normal individuals. No difference was detected between groups in the production of the Th1 cytokine IFN-gamma or the Th1-affiliated chemokines CXCL10 and CXCL11. Exogenous IL-10 significantly suppressed spontaneous and induced production of both Th1- and Th2-associated cytokines and chemokines. Our work demonstrated that locally manifested allergic rhinitis is underlined by a systemic Th2 immune response specific to allergens. The molecular pathogenesis of allergic rhinitis may be linked to a compromised allergen-specific immune regulation, e.g., reduced spontaneous and allergen-induced TGF-beta production in patients compared with healthy controls. Our data also show that IL-10 inhibits both the effector and directional mechanisms of allergen-specific immune response, further supporting its potential therapeutic benefit in preventing and treating allergic diseases.

Comparision of Compositional Differences and Relative Potency Between Different Manufacturers of Ragweed Pollen Extracts

RATIONALE: Ragweed extract (RWE) manufacturers must meet rigorous FDA standards and any change in producers must not negatively impact relative potency (RP) of the product. We evaluated the compositional differences (CD) and RP of an investigational RWE prepared by Lonza (LZ) [Visp: 198u Amb a 1] for Curalogic (Copenhagen) to the RWE [Hollister-Stier (HST): 259u] used in their prior US studies. METHODS: Serial endpoint titration [parallel-line bioassay method] was utilized to assess RP of the two test products which were also contrasted to a licensed (reference) US RWE [Greer (197u Amb a 1)]. Linear regression modeling calculated the best-fit (least squares) straight line for each assay [4-point ID titration (ΣE=50 mm)]. RESULTS: 8 subjects completed the study [mean age: 40; range: 30-57); mn RW puncture skin test sensitivity (ΣE): 80mm (med: 82.5; range: 45-100). Six subjects had valid assays [correlation of coefficient (R): ≥0.92; slope: ≥13mm]. CD (measured by standard deviation of the mn log3 RP): 0.595 [CDER upper limit: 0.68] demonstrated the LZ RWE was not different from the comparator (HST). The LZ RWE RP was 85% of the comparator [mn log3 RP: -0.4; SD: 0.595], thus the 2 RWE can be considered equal in potency [reference %: 71-141]. The LZ and HST RWE potencies were 127 and 171% of the non-dialyzed reference RWE. CONCLUSIONS: The CD and RP of RWE manufactured by LZ was demonstrated to be compositionally similar and equal in potency to its comparator RWE and highlights the importance of dialyzing the allergen in the manufacture of the product.

Lactoferrin decreases pollen antigen‐induced allergic airway inflammation in a murine model of asthma

Pollen grains contain reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidases and in contact with mucosal surfaces generate superoxide anion (O2*-). In the presence of iron, O2*- may be converted to more reactive oxygen radicals, such as to H2O2 and/or *OH, which may augment antigen-induced airway inflammation. The aim of the study was to examine the impact of lactoferrin (LF), an iron-binding protein, on ragweed (Ambrosia artemisiifolia) pollen extract (RWE)-induced cellular oxidative stress levels in cultured bronchial epithelial cells and accumulation of inflammatory and mucin-producing cells in airways in a mouse model of allergic airway inflammation. Results show that LF lowered RWE-induced increase in cellular reactive oxygen species (ROS) levels in bronchial epithelial cells. Most importantly, LF significantly decreased accumulation of eosinophils into airways and subepithelium of intranasally challenged, sensitized mice. LF also prevented development of mucin-producing cells. Amb a 1, the major allergenic ragweed pollen antigen lacking NADPH oxidase activity, induced low-grade airway inflammation. When administered along with glucose oxidase (G-ox), a superoxide-generating enzyme, Amb a 1 induced robust airway inflammation, which was significantly lowered by LF. Surprisingly, LF decreased also inflammation caused by Amb a 1 alone. Iron-saturated hololactoferrin had only a marginal effect on RWE-induced cellular ROS levels and RWE- or Amb a 1 plus G-ox-induced inflammation. We postulate that free iron in the airways chemically reduces O2*- to more reactive species which augment antigen-induced inflammation in a mouse model of asthma. Our results suggest the utility of LF in human allergic inflammatory disorders.

Artemisia and Ambrosia hypersensitivity: co‐sensitization or co‐recognition?

Ragweed and mugwort have nearly identical flowering periods. Clinical and serological studies showed that ragweed and mugwort sensitization are often associated and this poses relevant clinical problems in patients for whom specific immunotherapy is warranted. To establish whether the concurrent ragweed and mugwort pollen hypersensitivity is the result of co-sensitization or of co-recognition by using purified recombinant allergens. Sensitization to ragweed and mugwort pollen was assessed by skin prick test (SPT) in all patients reporting allergic symptoms in August and September. IgE reactivity of sera from 42 patients (26 Amb+/Art+, 14 Amb+/Art-, and two Amb-/Art+) to ragweed and mugwort pollen extract as well as to several recombinant ragweed (rAmb a 1, rAmb a 5, rAmb a 6, rAmb a 8, rAmb a 9, and Amb a 10) and mugwort (rArt v 1, rArt v 4, rArt v 5, rArt v 6, and three EF-hand calcium-binding protein) allergens was detected by dot-blot and ELISA analyses. IgE reactivity of 372 weed pollen-allergic patients was studied. Mugwort reactivity was strongly associated with ragweed hypersensitivity: only 10/147 (7%) mugwort-hypersensitive patients were not sensitized to ragweed, whereas 225/362 (62%) ragweed-hypersensitive patients were not sensitized to mugwort. In vitro, 90% of ragweed-allergic patients reacted with rAmb a 1. Reactivity to other ragweed allergens ranged between 20% and 35%. Forty-six percent of the mugwort-sensitized patients recognized rArt v 1%, 25% reacted to Art v 4, Art v 5, and Art v 6, and 7% recognized the three-EF hand calcium-binding protein. Immunoblot inhibition experiments showed that pre-incubation with ragweed pollen extract only weakly decreased IgE reactivity to mugwort allergens. Patients showing both ragweed- and mugwort-positive SPT and/or RAST are co-sensitized. Future studies will establish whether IgE reactivity translates into clinical symptoms and, hence, if co-sensitized patients should undergo specific immunotherapy with extracts of both mugwort and ragweed pollen.

Beyond Our Pages

Beyond Our Pages

ROS generated by pollen NADPH oxidase provide a signal that augments antigen-induced allergic airway inflammation

Pollen exposure induces allergic airway inflammation in sensitized subjects. The role of antigenic pollen proteins in the induction of allergic airway inflammation is well characterized, but the contribution of other constituents in pollen grains to this process is unknown. Here we show that pollen grains and their extracts contain intrinsic NADPH oxidases. The pollen NADPH oxidases rapidly increased the levels of ROS in lung epithelium as well as the amount of oxidized glutathione (GSSG) and 4-hydroxynonenal (4-HNE) in airway-lining fluid. These oxidases, as well as products of oxidative stress (such as GSSG and 4-HNE) generated by these enzymes, induced neutrophil recruitment to the airways independent of the adaptive immune response. Removal of pollen NADPH oxidase activity from the challenge material reduced antigen-induced allergic airway inflammation, the number of mucin-containing cells in airway epithelium, and antigen-specific IgE levels in sensitized mice. Furthermore, challenge with Amb a 1, the major antigen in ragweed pollen extract that does not possess NADPH oxidase activity, induced low-grade allergic airway inflammation. Addition of GSSG or 4-HNE to Amb a 1 challenge material boosted allergic airway inflammation. We propose that oxidative stress generated by pollen NADPH oxidases (signal 1) augments allergic airway inflammation induced by pollen antigen (signal 2).

Altered trafficking of cells during acute pulmonary allergic and viral inflammatory stimuli in rats with the chronic postbronchiolitis asthma-like phenotype

and Viral Inflammatory Stimuli in Rats With the Chronic Postbronchiolitis Asthma-Like Phenotype R. L. SORKNESS1, L. A. ROSENTHAL2, T. PIER2, S. P. AMINEVA2, R. J. SZAKALY2, R. F. LEMANSKE, Jr.3; 1Sch of pharmacy, UNIVERSITY OF WISCONSIN, Madison, WI, 2Medicine, UNIVERSITY OF WISCONSIN, Madison, WI, 3Pediatrics, UNIVERSITY OF WISCONSIN, Madison, WI. RATIONALE: Airway inflammation in asthma may be due to enhanced vulnerability of airways to common inflammatory stimuli. We hypothesized that rats with chronic airway dysfunction would differ from normals in their acute pulmonary inflammatory responses. METHODS: Normal BN rats were compared with asthma-like BN rats that were >10wks post early age bronchiolitis. Acute allergic inflammation was induced by a single exposure to aerosolized ragweed pollen extract 2wks after sensitization, and evaluated at 1 or 7 days; viral inflammation was induced with a tracheal insufflation of attenuated mengovirus, and evaluated in 3 days. Airspace infiltrates were quantified with bronchoalveolar lavage (BAL), and airway wall eosinophils (eos) with staining of major basic protein (MBP) in lung sections. RESULTS: Unchallenged normal and asthma-like rats did not differ significantly with regard to BAL eos or airway MBP. However, the asthmalike rats had significantly greater airway wall MBP (p=0.001) and fewer BAL eos (p=0.02) 1 day after allergen challenge, and fewer BAL eos (p=0.04) with similar airway MBP 7 days after allergen. During viral infection a similar pattern occurred, the asthma-like rats having few eos and neutrophils in BAL (p<0.04), but present in lung sections. BAL viral titers were similar in the 2 groups. CONCLUSION: During acute inflammation the asthma-like rats have fewer eos present in the airspace, but equal or greater numbers in airway walls, compared with normals. These data are consistent with the hypothesis that asthmatic airways exhibit different patterns of inflammatory cell trafficking that result in greater vulnerability of the airways to allergic or viral insults. J ALLERGY CLIN IMMUNOL Abstracts S47 VOLUME 115, NUMBER 2

Systemic and pulmonary effects of fluticasone administered through a metered-dose inhaler in rats

Metered-dose inhalers (MDIs) are convenient, simple, inexpensive, and reproducible devices for administering aerosolized drugs through the pulmonary route, but methods have not been available for use of these devices in small animals. We sought to test the efficacy of delivery of fluticasone through an MDI to rats with a rodent-adapted spacer chamber and to compare this treatment with systemic dexamethasone for the acute pulmonary allergic inflammatory response. Changes in body and thymus weights were used as indicators for systemic steroid effects. Rats were sensitized to ragweed pollen extract 2 weeks before the experiment, and pulmonary allergic responses were evaluated 48 hours after a single aerosolized antigen challenge on the basis of bronchoalveolar leukocytes, lung tissue sections, total lung capacity, and forced expiratory volumes. Inhaled fluticasone caused dose-related systemic effects, indicating successful pulmonary drug delivery. Inhaled fluticasone was more effective than placebo but less effective than systemic dexamethasone in attenuating the increase in lung eosinophils and inflammatory infiltrates and the decrease in total lung capacity associated with the allergic inflammatory response. Inhaled fluticasone prevented airway obstruction and proximal inflammation, as did dexamethasone, but it appeared to have less effect in areas of lung served by the most distal airways. This is an effective method for use of MDIs to deliver inhaled drugs to small laboratory animals, and it should be valuable for investigations of treatment effects, as well as for in vivo testing of delivery devices.

Stimulation of innate immune response induces long term allergic sensitization and allergic airway inflammation independent of STAT-6

Rationale According to the current paradigm, the transcription factor STAT6 is required for induction of allergic sensitization and allergic airway inflammation. Recent studies have shown that stimulation of innate immune responses profoundly modulate many immune responses. The conserved MyD88 signaling pathway of innate immune response can be stimulated by the cytokine IL-18. We have reported that intrapulmonary administration of IL-18 with ragweed pollen extract (RWE) induces allergic sensitization and allergic inflammation in wild type mice. Here we examined role of IL-18 on long-term induction of allergic sensitization in mice lacking STAT-6. Methods To examine the long-term effects of intrapulmonary administration of IL-18, wild type and STAT6 knockout mice received intranasally either RWE or RWE+IL-18. 12 weeks later, all mice were challenged with RWE. 72 hours later a BAL was performed. BUXCO plethysmography was used to monitor AHR. Antigen recalls studies were performed using splenocytes. Serum RWE-specific IgE ELISA also quantified. Statistical significance was set at p<0.05. Results Compared to the mice sensitized with RWE, RWE challenge of both wild type and STAT6 deficient mice sensitized with RWE+IL-18 induced 5-fold higher recruitment of eosinophils (p<0.01), 11-fold higher serum IgE levels (p<0.0001), 2-fold higher airway hyperesponsiveness (p<0.05) and 10- to 25-fold higher splenocytes Th2 memory responses (<0.001). Conclusions Stimulation of the innate immune response by intrapulmonary administration of IL-18 induces long lasting (12 weeks) allergic sensitization, AHR, allergic airway inflammation and Th2 memory via a novel STAT-6 independent pathway.

Intrinsic pollen NADPH oxidases induce genes by activating innate immune responses in human bronchial epithelial cells

Rationale We recently identified intrinsic NADPH-oxidase activity (NOA) in ragweed pollen extract (RWE) that induces oxidative stress in cultured bronchial epithelial cells and in vivo in the airway epithelial cells of mice. This NOA plays a key role in allergic inflammation (Boldogh et al). We hypothesized that NOA may directly modulate gene expression in airway epithelial cells via innate immune pathways. Methods A549 cells, a human bronchial epithelial cell line, were exposed to RWE for 1, 3, and 6 hours, and compared to an unexposed control. Cellular mRNA was analyzed for 15,000 genes by Affymetrix® HG-U133A GeneChip® microarray. Probe sets with an absolute fold change ≥2X from control were compared using a Venn analysis. Candidate genes were compared to three model time-course profiles and ranked by their correlation coefficient against the model trajectory: 1) progressively up/down with time, 2) up/down at 1 hour post-exposure, and 3) up/down at 3 hours post-exposure. Results Venn analysis showed that RWE with NOA had up-regulated 155 genes by 1 hour, 213 genes by 3 hours, and 193 genes by 6 hours more than 2 fold relative to the control. Likewise, RWE with NOA had down-regulated 100 genes by 1 hour, 118 genes by 3 hours, and 80 genes by 6 hours. Profile searches identified 68 genes that positively or negatively correlated at the 95% limit with profile 1, 63 with profile 2 and 82 with profile 3. Conclusions NOA modulates many genes in bronchial epithelial cells by activation of innate immune networks in epithelial cells.

Cetirizine, an H1-receptor antagonist, suppresses the expression of macrophage migration inhibitory factor: its potential anti-inflammatory action.

H1-receptor antagonists are often effective in the treatment of allergic disorders such as atopic dermatitis. Cetirizine, a putative H1-receptor antagonist, has recently been shown to have anti-inflammatory properties through the inhibition of leucocyte recruitment and activation, and by the reduction of ICAM-1 expression on keratinocytes. To further elucidate the anti-inflammatory properties of cetirizine, we first examined its effects on antigen-induced eosinophilia and neutrophila in vivo. We then examined the anti-inflammatory effects of cetirizine on a human keratinocyte A431cell line. Mice were sensitized subcutaneously with ragweed pollen and were challenged intraperitoneally with the allergen. Cetirizine diluted in sterile water (0-20 mg/kg) or only sterile water was administered orally. Peritoneal cells were obtained at 8 and 24 h after challenge. The eosinophilia and neutrophilia induced by ragweed pollen extract were quantitated. Macrophage migration inhibitory factor (MIF), macrophage inflammatory protein 2 (MIP-2) and eotaxin contents of peritoneal fluid were also measured by mouse ELISA. The effects of cetirizine on MIF-induced IL-8 production in A431 cells were examined by ELISA. The effects of cetirizine on MIF expression and production in A431 cells were examined by human MIF ELISA and Northern blot analysis. Eosinophilia and neutrophilia induced by ragweed pollen extract were found to be significantly reduced in cetirizine-treated mice (20 mg/kg). MIF, a pleuripotent cytokine, was significantly decreased at 8 and 24 h in the peritoneal fluid by cetirizine treatment. MIP-2 and eotaxin were also decreased 8 and 24 h, respectively, after challenge in the peritoneal fluid with cetirizine treatment. MIF stimulates IL-8 production in A431 cells. We found that MIF production in A431 cells was inhibited by 10 microm cetirizine. Consistent with this, cetirizine significantly inhibited MIF-induced IL-8 production. These results suggest that cetirizine exerts its anti-inflammatory effects by inhibiting MIF as well as IL-8 production, such as those involved in inflammatory allergic skin disease, suggesting a broad spectrum of action beyond its mere H1-receptor-antagonistic function.

Loveless on wasp venom allergy and immunity- part 1

Loveless on wasp venom allergy and immunity- part 1