Nasal mucosa and blood cell transcriptome profiles do not reflect respiratory symptoms associated with moisture damage.

Upper and lower respiratory symptoms and asthma are adverse health effects associated with moisture-damaged buildings. Quantitative measures to detect adverse health effects related to exposure to dampness and mold are needed. Here, we investigate differences in gene expression between occupants of moisture-damaged and reference buildings. Moisture-damaged (N = 11) and control (N = 5) buildings were evaluated for dampness and mold by trained inspectors. The transcriptomics cohort consisted of nasal brushings and peripheral blood mononuclear cells (PBMCs) from 86 teachers, with/without self-perceived respiratory symptoms. Subject categories comprised reference (R) and damaged (D) buildings with (S) or without (NS) symptoms, that is, R-S, R-NS, DS, and D-NS. Component analyses and k-means clustering of transcriptome profiles did not distinguish building status (R/D) or presence of respiratory symptoms (S/NS). Only one nasal mucosa gene (YBX3P1) exhibited a significant change in expression between D-S and D-NS. Nine other nasal mucosa genes were differentially expressed between R-S and D-S teachers. No differentially expressed genes were identified in PBMCs. We conclude that the observed mRNA differences provide very weak biological evidence for adverse health effects associated with subject occupancy of the specified moisture-damaged buildings. This emphasizes the need to evaluate all potential factors (including those not related to toxicity) influencing perceived/self-reported ill health in moisture-damaged buildings.

A novel glycocluster molecule prevents timothy-induced allergic airway inflammation in mice.

BACKGROUND: Allergen-specific immunotherapy (SIT) effectively alleviates type I allergic diseases characterized by T helper (Th)2-type immunity. Our recent studies have shown that a synthetic trivalent glycocluster, triacedimannose (TADM), suppresses the Th2-type allergic inflammation. The aim of this study was to compare TADM with two well-known adjuvants, unmethylated cytosine-phosphate-guanine oligodeoxynucleotide (CpG) and monophosphoryl lipid A (MPLA) in a grass allergen-induced chronic allergic inflammation model in mice. METHODS: Female BALB/c mice were intranasally sensitized with 50 µL of timothy grass pollen extract (TE) twice a week for a period of 15 weeks. Therapeutic intranasal treatments were then performed once a week after the tenth intranasal TE instillation using TADM (10 or 25 µg/50 µL), CpG-ODN (20 µg/50 µL) or MPLA (2 µg/50 µL). Groups of 9-10 animals per treatment were killed 24 hours after the last timothy dosage. Blood, bronchoalveolar lavage (BAL) fluids and lung biopsies were taken for subsequent analysis. RESULTS: When mice were repeatedly exposed to TE for 15 weeks, the number of eosinophils and lymphocytes increased in the BAL fluids. The eosinophil and lymphocyte counts decreased dose-dependently and were practically abolished in the mice treated with TADM. Treatments with MPLA or CpG significantly increased the numbers of neutrophils, while CpG nonsignificantly decreased eosinophilia compared to timothy exposure. CONCLUSIONS: A novel synthetic glycocluster molecule inhibited the development of grass-induced eosinophilic pulmonary inflammation in mice when administrated in the airways. This compound could be a candidate to be used either as an adjuvant in SIT or as a topical anti-inflammatory treatment.

Significant disparities in allergy prevalence and microbiota between the young people in Finnish and Russian Karelia.

BACKGROUND: Atopic allergy has been more common among schoolchildren in Finland, as compared to Russian Karelia. These adjacent regions show one of the most contrasting socio-economical differences in the world. OBJECTIVE: We explored changes in allergy from school age to young adulthood from 2003 to 2010/2012 in these two areas. The skin and nasal microbiota were also compared. METHODS: Randomly selected children from Finnish (n = 98) and Russian Karelia (n = 82) were examined in 2003, when the children were 7-11 years of age, and again in 2010 (Finnish Karelia) and 2012 (Russian Karelia). We analysed self-reported allergy symptoms and sensitization to common allergens by serum sIgE values. The skin (volar forearm) and nasal mucosa microbiota, collected in 2012 (aged 15-20 years), identified from DNA samples, were compared with multivariate methods. RESULTS: Asthma, hay fever, atopic eczema, self-reported rhinitis, as well as atopic sensitization, were threefold to 10-fold more common in Finland, as compared to Russian Karelia. Hay fever and peanut sensitization were almost non-existent in Russia. These patterns remained throughout the 10-year follow-up. Skin microbiota, as well as bacterial and fungal communities in nasal mucosa, was contrastingly different between the populations, best characterized by the diversity and abundance of genus Acinetobacter; more abundant and diverse in Russia. Overall, diversity was significantly higher among Russian subjects (Pskin < 0.0001, Pnasal-bacteria < 0.0001 and Pnasal-fungi < 0.01). Allergic diseases were not associated with microbial diversity in Finnish subjects. CONCLUSIONS AND CLINICAL RELEVANCE: Differences in allergic phenotype, developed in early life, remain between populations. A parallel difference in the composition of skin and nasal microbiota suggests a potential underlying mechanism. Our results also suggest that high abundance and diversity of Acinetobacter might contribute to the low allergy prevalence in Russia. Implications of early-life exposure to Acinetobacter should be further investigated.

A novel mannoside-glycocluster adjuvant: Compared in vitro to CpG ODN and MPL and tested in vivo in mouse asthma model

BACKGROUND: Allergen-specific immunotherapy balances the Th2-biased immunity towards Th1 and Treg responses. Adjuvants are used in allergen preparations to intensify the immune responses. The increased prevalence of allergies in developed societies has been associated with decreased microbial load during childhood. This has initiated a search for microbial structures to be used as adjuvants. Our study has shown that a synthetic triacedimannose (TADM) may suppress the Th2-type allergic inflammatory response. The aim of this study was to compare the properties of TADM with capacities of other adjuvants, CpG ODN and MPL, to modulate cytokine production in PBMC and regulate sensitisation in an OVA-sensitised mouse asthma model. METHODS: The effects of TADM were studied in vitro on birch stimulated PBMC cultures of birch allergic rhinitis patients with other known adjuvants. Cytokines in supernatants were measured by Luminex. Effects of TADM were analysed in vivo in a mouse model of OVA-induced allergic asthma by analysing BAL, cytokine mRNA and serum antibodies. RESULTS: TADM was the only adjuvant that significantly suppressed the production of all birch induced Th2-type cytokines. In a murine model, TADM significantly suppressed the specific IgE production and enhanced IFN-γ production. CONCLUSIONS: TADM suppresses the birch allergen induced Th2-type cytokine responses in allergic subjects more efficiently than the two other adjuvants, MPL and CpG ODN. TADM is immunomodulatory also in vivo and decreases the IgE levels and increases the IFN-γ responses in a murine model. These results suggest that TADM may be a promising candidate for novel adjuvants in immunotherapy

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A novel mannoside-glycocluster adjuvant: Compared in vitro to CpG ODN and MPL and tested in vivo in mouse asthma model.

BACKGROUND: Allergen-specific immunotherapy balances the Th2-biased immunity towards Th1 and Treg responses. Adjuvants are used in allergen preparations to intensify the immune responses. The increased prevalence of allergies in developed societies has been associated with decreased microbial load during childhood. This has initiated a search for microbial structures to be used as adjuvants. Our study has shown that a synthetic triacedimannose (TADM) may suppress the Th2-type allergic inflammatory response. The aim of this study was to compare the properties of TADM with capacities of other adjuvants, CpG ODN and MPL, to modulate cytokine production in PBMC and regulate sensitisation in an OVA-sensitised mouse asthma model. METHODS: The effects of TADM were studied in vitro on birch stimulated PBMC cultures of birch allergic rhinitis patients with other known adjuvants. Cytokines in supernatants were measured by Luminex. Effects of TADM were analysed in vivo in a mouse model of OVA-induced allergic asthma by analysing BAL, cytokine mRNA and serum antibodies. RESULTS: TADM was the only adjuvant that significantly suppressed the production of all birch induced Th2-type cytokines. In a murine model, TADM significantly suppressed the specific IgE production and enhanced IFN-γ production. CONCLUSIONS: TADM suppresses the birch allergen induced Th2-type cytokine responses in allergic subjects more efficiently than the two other adjuvants, MPL and CpG ODN. TADM is immunomodulatory also in vivo and decreases the IgE levels and increases the IFN-γ responses in a murine model. These results suggest that TADM may be a promising candidate for novel adjuvants in immunotherapy.

Hunt for the origin of allergy - comparing the Finnish and Russian Karelia.

The Finnish and Russian Karelia are adjacent areas in northern Europe, socio-economically distinct but geoclimatically similar. The Karelia Allergy Study was commenced in 1998 to characterize the allergy profiles in the two areas. Allergy prevalence had increased in Finland since the early 1960s, but the situation in Russia was unknown. The key finding was that allergic symptoms and diseases were systematically more common in Finnish children and adults than in their Russian counterparts. For example, in the early 2000s, hay fever in school children was almost non-existent in Russian Karelia, and only 2% were sensitized to birch pollen compared with 27% in Finnish Karelia. Adult birth cohorts showed that among those born in the 1940s, the sensitization to pollens and pets was at the same low level in both countries, but among younger generation born in the late 1970s, the difference was already manifold. Seropositivity to some pathogens, microbial content in house dust and drinking water seemed to confer allergy protection in Russia. In subsequent studies, it became apparent that on the Finnish side, healthy children had a more biodiverse living environment as well as greater diversity of certain bacterial classes on their skin than atopic children. Abundance of skin commensals, especially Acinetobacter (gammaproteobacteria), associated with anti-inflammatory gene expression in blood leucocytes. In vivo experiments with the mouse model demonstrated that intradermally applied Acinetobacter protected against atopic sensitization and lung inflammation. These observations support the notion that the epidemic of allergy and asthma results from reduced exposure to natural environments with rich microbiota, changed diet and sedentary lifestyle. Genetic studies have confirmed strong influence of lifestyle and environment. With our results from the Karelia study, a 10-year National Allergy Programme was started in 2008 to combat the epidemic in Finland.

Interleukin-6 as a predictor of symptom resolution in psychological distress: a cohort study.

BACKGROUND: Elevated levels of interleukin-6 (IL-6) have been associated with the development of common mental disorders, such as depression, but its role in symptom resolution is unclear. METHOD: We examined the association between IL-6 and symptom resolution in a non-clinical sample of participants with psychological distress. RESULTS: Relative to high IL-6 levels, low levels at baseline were associated with symptom resolution at follow-up [age- and sex-adjusted risk ratio (RR) = 1.15, 95% confidence interval (CI) 1.06-1.25]. Further adjustment for covariates had little effect on the association. Symptomatic participants with repeated low IL-6 were more likely to be symptom-free at follow-up compared with those with repeated high IL-6 (RR = 1.21, 95% CI 1.03-1.41). Among the symptomatic participants with elevated IL-6 at baseline, IL-6 decreased along with symptom resolution. CONCLUSIONS: IL-6 is potentially related to the mechanisms underlying recovery from symptoms of mental ill health. Further studies are needed to examine these mechanisms and to confirm the findings in relation to clinical depression.

Physical interactions between mast cells and eosinophils: a novel mechanism enhancing eosinophil survival in vitro.

BACKGROUND: Mast cells (MCs) and eosinophils (Eos) are the key effector cells of the allergic reaction. Although classically associated with different stages of the response, the cells co-exist in the inflamed tissue in the late and chronic phases in high numbers and are likely to cross-talk. While some mediators of MCs are known to affect Eos biology and vice versa, paracrine and physical interplay between the two cells has not been described yet. We aimed to investigate whether intercellular MC-Eos communication could take place in the allergic response and exert functional bidirectional changes on the cells. METHODS: Tissue sections from various allergic disorders were specifically stained for both cells. Human cord blood-derived MCs and peripheral blood Eos, co-cultured under different conditions, were studied by advanced microscopy and flow cytometry. RESULTS: Several co-localized MC-Eos pairs were detected in human nasal polyps and asthmatic bronchi, as well in mouse atopic dermatitis. In vitro, MCs and Eos formed stable conjugates at high rates, with clear membrane contact. In the presence of MCs, Eos were significantly more viable under several co-culture conditions and at both IgE-activated and steroid-inhibited settings. MC regulation of Eos survival required communication through soluble mediators but was even more dependent on physical cell-cell contact. CONCLUSIONS: Our findings provide the first evidence for a complex network of paracrine and membrane interactions between MCs and Eos. The prosurvival phenotype induced by this MC-Eos interplay may be critical for sustaining chronic allergic inflammation.

Narrowband ultraviolet B treatment improves vitamin D balance and alters antimicrobial peptide expression in skin lesions of psoriasis and atopic dermatitis.

BACKGROUND: Narrowband ultraviolet B (NB-UVB) is a routine treatment for psoriasis and atopic dermatitis (AD) but its effect on vitamin D balance is not well studied. OBJECTIVES: To examine whether NB-UVB treatment in winter improves vitamin D balance in psoriasis and AD, and to study the effects of NB-UVB on antimicrobial peptide and cytokine expression in the skin. METHODS: Eighteen adult patients with psoriasis, 18 with AD and 15 healthy subjects received a total of 15 NB-UVB exposures on the whole body, given three times a week. Serum calcidiol (25-hydroxyvitamin D) was measured by radioimmunoassay. Antimicrobial peptide and cytokine expression in skin lesions was examined by real-time quantitative polymerase chain reaction. RESULTS: At onset 16 (89%) patients with psoriasis, 17 (94%) patients with AD and eight (53%) healthy subjects had vitamin D insufficiency (calcidiol < 50 nmol L(-1)). NB-UVB treatment significantly increased (P < 0.001) serum calcidiol. The increase was 59.9 nmol L(-1) (95% confidence interval, CI 53.5-66.9) in psoriasis, 68.2 nmol L(-1) (95% CI 55.4-80.1) in AD and 90.7 nmol L(-1) (95% CI 63.8-123.4) in healthy subjects. Psoriasis Area and Severity Index and SCORAD improved significantly (P < 0.001) but no correlation to the increase of serum calcidiol was found. Cathelicidin and human beta-defensin 2 (HBD2) expression was high in skin lesions of psoriasis. After six NB-UVB treatments cathelicidin increased further while HBD2 expression decreased. A similar trend was observed in AD lesions. NB-UVB caused a marked but nonsignificant decrease of interleukin (IL)-1beta and IL-17 in psoriasis lesions. CONCLUSIONS: The present study shows that in addition to a significant improvement of psoriasis and AD, NB-UVB treatment effectively corrects vitamin D insufficiency. It also increases cathelicidin and decreases HBD2 levels in healing skin lesions of psoriasis and AD. This effect might be mediated by improved vitamin D balance and the local cytokine network.

Matrix metalloproteinases-7, -8, -9 and TIMP-1 in the follow-up of diisocyanate-induced asthma.

BACKGROUND: Diisocyanate-induced asthma (DIA) is known to be associated with poor prognosis. We wished to clarify if matrix metalloproteinases (MMP)-7, -8 or -9 or tissue inhibitor of matrix metalloproteinases (TIMP-1) are associated with the functional or inflammatory outcome in DIA patients. METHODS: This is a longitudinal study where 17 patients with DIA diagnosed by a specific challenge test to diisocyanates were monitored. Exposure to diisocyanates was terminated seven (mean) months before the challenge test. The studies included spirometry, histamine challenge test and bronchoscopy. MMP-7, MMP-8, TIMP-1 [Enzyme-linked immunosorbent assay (ELISA)- and immunofluorometric assay-methods], MMP-9 (ELISA and zymography), interferon-gamma, tumour necrosis factor-alpha, interleukin-6, -8, -15, -17, CXCL-5/ENA-78, monocyte chemoattractant protein-1 and macrophage inhibitory factor (MIF) (ELISA) were assayed from bronchoalveolar lavage (BAL) fluid. Inhaled steroid therapy was initiated after the examinations, which were repeated at 6 months and at 3 years during the treatment. The results were compared with those of 15 healthy controls. RESULTS: Inhaled steroid medication increased BAL levels of MMP-9 and MMP-9/TIMP-1 and decreased MMP-7 and MMP-7/TIMP-1. The increase in MMP-9 levels was associated with a decline in the TH-2 type inflammation. CONCLUSIONS: Our data suggest that reduced TH-2 type inflammation in DIA after inhaled steroid medication is reflected as elevated MMP-9 and MMP-9/TIMP-1 levels in BAL. MIF may be the inducer of MMP-9. This might point to some protective role for MMP-9 in DIA.

Engineered nanomaterials cause cytotoxicity and activation on mouse antigen presenting cells.

Nanomaterials improve everyday products but their safety for human health is poorly known. In this study we explored immunological effects of five different nanomaterials on antigen presenting cells (APC) in vitro. Nanomaterials studied were rutile titanium dioxide (TiO2), amorphous silica-coated rutile titanium dioxide (TiO2-silica), zinc oxide (ZnO), single-walled carbon nanotubes (SWCNT) and multi-walled carbon nanotubes (MWCNT). APCs included mouse macrophages (RAW 264.7 cell line) and murine bone marrow-derived dendritic cells (bmDC). All studied particles were cytotoxic to bmDCs, and ZnO, TiO2 and TiO2-silica-induced dose-dependently cell death also in macrophages. ZnO had the most drastic immunological effects leading to high expression of proinflammatory cytokine, IL-1beta, and enhanced production of neutrophil chemoattractant CXCL-9 on both cell types. TiO2 and TiO2-silica stimulated the expression of IL-6, MIP-1alpha and TNF-alpha in macrophages, and increased their maturation, antigen presentation and co-stimulation activity. In contrast, SWCNT or MWCNT did not seem to have any significant immunological effects on the cell types studied suggesting that APCs might not be the target cells for carbon nanotubes. Due to diverse effects on different nanomaterials on immune cells we suggest that each new nanomaterial should be extensively studied in vitro and in vivo for risk assessment before their use in final products.

Neuropeptide S receptor 1 expression in the intestine and skin--putative role in peptide hormone secretion.

Neuropeptide S receptor 1 (NPSR1) was recently found to be genetically associated with inflammatory bowel disease in addition to asthma and related traits. Epithelia of several organs express NPSR1 isoforms A and B, including the intestine and the skin, and NPSR1 appears to be upregulated in inflammation. In this study, we used cell lines and tissue samples to characterize the expression of NPSR1 and its ligand neuropeptide S (NPS) in inflammation. We used polyclonal and monoclonal antibodies to investigate the expression of NPS and NPSR1 in intestinal diseases, such as celiac disease and food allergy, and in cutaneous inflammatory disorders. We found that NPSR1-A was expressed by the enteroendocrine cells of the gut. Overall, the expression pattern of NPS was similar to its receptor suggesting an autocrine mechanism. In an NPSR1-A overexpressing cell model, stimulation with NPS resulted in a dose-dependent upregulation of glycoprotein hormone, alpha polypeptide (CGA), tachykinin 1 (TAC1), neurotensin (NTS) and galanin (GAL) encoding peptide hormones secreted by enteroendocrine cells. Because NPSR1 was also expressed in macrophages, neutrophils, and intraepithelial lymphocytes, we demonstrated that stimulation with the pro-inflammatory cytokines tumour necrosis factor alpha and interferon gamma increased NPSR1 expression in the THP-1 monocytic cells. In conclusion, similar to other neuropeptides and their receptors, NPSR1 signalling might play a dual role along the gut-brain axis. The NPS/NPSR1 pathway may participate in the regulation of the peptide hormone production in enteroendocrine cells of the small intestine.

Transforming growth factor-beta/Smad3 signalling regulates inflammatory responses in a murine model of contact hypersensitivity.

BACKGROUND: Transforming growth factor (TGF)-beta is an important modulator of immune functions and cellular responses, such as differentiation, proliferation, migration and apoptosis. The Smad proteins, which are intracellular TGF-beta signal transducers, mediate most actions of TGF-beta. OBJECTIVES: This study examines the role of Smad3 in a murine model of contact hypersensitivity (CHS). METHODS: The CHS response to oxazolone was studied in Smad3-deficient mice. The ear swelling response was measured and skin biopsies from oxazolone-sensitized skin areas were obtained for RNA isolation, immunohistochemical analyses and histology. Ear draining lymph nodes were collected for RNA isolation and proliferation tests. Quantitative real-time polymerase chain reaction was used to quantify mRNA expression of cytokines, chemokines and transcription factors. Results The expression of proinflammatory [interleukin (IL)-1beta, tumour necrosis factor-alpha, IL-6], Th2 (IL-4) and Th17 type cytokines (IL-17), as well as regulatory components (TGF-beta, Foxp3) increased significantly at the mRNA level in the skin of oxazolone-treated Smad3-/- mice when compared with wild-type controls. The expression of the Th1 type cytokine IFN-gamma and the chemokines CXCL9 and CXCL10 was, however, unaffected by the lack of Smad3. The number of neutrophils and expression of the chemokines CCL3 and CXCL5, which are both involved in neutrophil recruitment, were increased in mice lacking Smad3. Also Th2 type chemokines CCL24, CCL3 and CXCL5 were increased in the skin of Smad3-/- mice compared with wild-type mice. In the lymph nodes, mRNA of IL-1beta and IL-17, but not IL-4, TGF-beta or Foxp3, was increased in Smad3-/- mice during the CHS response. CONCLUSIONS: The lack of intact TGF-beta signalling via Smad3 results in an increased proinflammatory, Th2 and Th17 type response in the skin, as well as increased expression of regulatory elements such as TGF-beta and Foxp3. Understanding the role of Smad3 in the CHS response may offer treatment and prevention strategies in this often disabling disease.

Inflammation and functional outcome in diisocyanate-induced asthma after cessation of exposure.

BACKGROUND: The clinical outcome of diisocyanate-induced asthma has been found to be poor despite cessation of exposure. Our aim was to study the outcome of diisocyanate-induced asthma after initiation of inhaled steroid treatment at a mean period of 7 months (range 2-60 months) after cessation of exposure by following up lung function and bronchial inflammation. METHODS: Bronchoscopy was performed on 17 patients 2 days after a positive inhalation challenge test, after which budesonide 1600 mug a day was started. Bronchoscopy, spirometry, and histamine challenge tests were repeated at 6 months and on average 3 years. The results were also compared with those obtained from 15 healthy control subjects. RESULTS: Nonspecific bronchial hyperreactivity diminished significantly (P = 0.006); however, forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) values decreased, with a median yearly reduction of FEV1 of 79 ml. The count of mast cells in bronchial mucosa decreased (P = 0.012) and that of macrophages increased (P = 0.001). Interleukin-4 level in mucosa was during the first year significantly higher than in controls but its level decreased in the follow-up. Interleukin-6, interleukin-15, and tumour necrosis factor alpha messenger-RNA levels were significantly higher in hyperreactive patients than in nonhyperreactive patients at the end of the follow-up. CONCLUSION: Our results indicate that inflammation may persist in diisocyanate-induced asthma despite inhaled steroid medication. However, TH2-type inflammation diminished. Persistent nonspecific bronchial hyperreactivity was associated with proinflammatory acting cytokines produced mainly by macrophages. Considering the poor prognosis of the disease the findings could be utilized to develop the follow-up and treatment of diisocyanate-induced asthma.

Effects of fumonisin B(1) on the expression of cytokines and chemokines in human dendritic cells.

Fumonisin B(1) (FB(1)) is a mycotoxin produced by the fungus Fusarium verticillioides, which commonly infects corn and other crops across the world. Exposure to FB(1) is known to have toxic and carcinogenic effects in animals, and to express toxicity in cells. In this study, we investigated mechanisms whereby FB(1) may induce immunotoxic effects in human dendritic cells (DC) differentiated from human peripheral blood mononuclear cells. mRNA and protein levels of a number of cytokines and chemokines were analyzed in DC, after exposure to 100 microM FB(1), 10 ng/ml LPS, or a combination of 100 microM FB(1) and 10 ng/ml LPS for 6h or 24h. Exposure to FB(1) resulted in an increase in the expression of IFNgamma and CXCL9. Moreover, FB(1) inhibited the LPS-induced expression of IL-6, IL-1beta, CCL3 and CCL5. The other cytokines studied (TNFalpha, IL-12, IL-18 and IL-23) were not affected by FB(1) in DC. The results of this study indicate that FB(1) has an impact on the expression of cytokines and chemokines in human DC, and in addition to its other toxic effects, FB(1) may also be potentially immunotoxic to humans.

Latex allergy: low prevalence of immunoglobulin E to highly purified proteins Hev b 2 and Hev b 13.

BACKGROUND: Hevea brasiliensis (Hev b) 2 and Hev b 13 have recently been identified as major latex allergens by detecting specific IgE antibodies in >50% of sera from Hev b latex-allergic individuals. OBJECTIVE: We assessed the prevalence rates for sensitization to extensively purified latex allergens in patients from three diverse geographical areas. METHODS: Native Hev b 2, Hev b 5, Hev b 6.01 and Hev b 13 were purified by non-denaturating chromatography and were used in ELISAs to assess sera from 215 latex-allergic patients and 172 atopic non-sensitized controls from Finland, Spain and the United States to detect allergen-specific IgE antibodies. RESULTS: Unexpectedly, even highly purified Hev b 13 contained epitope(s) to which Hev b 6-specific human IgE antibodies bound effectively. Further purification, however, reduced the prevalence of IgE antibody reactivity to low levels: 15%, 5% and 11% for Hev b 2, and 18%, 30% and 27% for Hev b 13 among latex-allergic Finnish, Spanish and American patients, respectively. Interestingly, Finnish patients had a lower prevalence of Hev b 5-specific IgE antibody (28%) as compared with Spanish (49%) and American (71%) patients. The prevalence of Hev b 6.01-specific IgE reactivity was uniformly >50% in all three populations. CONCLUSION: Neither Hev b 2 nor Hev b 13 appear to be major latex allergens when evaluated in serological assays using highly purified allergens. The reason(s) for the observed differences in published sensitization rates in various geographic regions requires further study. The purity of the allergen preparations has a marked impact on the accuracy of latex-specific IgE antibody detection in epidemiological studies and in the serological diagnosis of latex allergy.

Latex allergy: the sum quantity of four major allergens shows the allergenic potential of medical gloves.

BACKGROUND: Assessment of allergenic potential of medical devices made of natural rubber latex (NRL) requires the measurement of concentrations of specific allergenic proteins or polypeptides eluting from rubber. METHODS: Four NRL allergens (Hev b 1, 3, 5, and 6.02) were quantified in all medical glove brands marketed in Finland in 1999, 2001, and 2003 (n = 208) by a capture enzyme immunoassay. The results were compared with those obtained from previous nationwide market surveys, using a skin prick test-validated human IgE-based ELISA-inhibition method. RESULTS: A high overall correlation (r = 0.87, 95% CI 0.83-0.90) emerged between the sum values of the four allergens(microg/g glove) and IgE-ELISA inhibition (allergen units, AU/ml, 1 : 5 diluted glove extract). The sum of four allergens when set at 0.15 microg/g discriminated 'low allergenic' (<10 AU/ml) from 'moderate- to high-allergenic' (>/=10 AU/ml) gloves at a sensitivity of 0.93 (95% CI 0.85-0.98) and specificity of 0.90 (95% CI 0.83-0.94). When the sum was below the detection limit (0.03 microg/g) all gloves belonged to the previously defined low-allergen category. CONCLUSIONS: By comparing the sum concentration of four selected NRL allergens with results obtained in human IgE-ELISA inhibition, it was possible set a cut-off level (0.15 microg/g) below which virtually all gloves contain low or insignificant amounts of allergens, and can be considered as low allergenic. At different cut-off-points, one could calculate the likelihood of a given glove to belong to the previously defined low, moderate or high allergen categories.

Hev b 6.01 and Hev b 5 induce pro-inflammatory cytokines and chemokines from peripheral blood mononuclear cells in latex allergy.

BACKGROUND: Hev b 6.01 (prohevein) and Hev b 5 [acidic natural rubber latex (NRL) protein] are major IgE-binding allergens in NRL allergy. OBJECTIVE: To examine allergen-specific cytokine and chemokine responses in NRL-allergic patients. METHODS: Fourteen NRL-allergic patients and 10 healthy controls participated in the study. Hev b 6.01 and Hev b 5 were purified under non-denaturating conditions by chromatographic methods. Specific IgE antibodies were measured by ELISA and proliferation of peripheral blood mononuclear cells (PBMC) by (3)H-thymidine incorporation assay. Allergen-specific induction of cytokine and chemokine mRNA in PBMC was measured by real-time PCR and protein levels by ELISA. Surface expression of chemokine receptors was analysed by flow cytometry. RESULTS: Twelve (86%) NRL-allergic patients had positive skin prick test reactions and IgE antibodies against Hev b 6.01, but less than 30% responded to Hev b 5. Cell proliferation against Hev b 6.01, but not against Hev b 5, was significantly increased. Both allergens elicited significantly higher expression of pro-inflammatory and T-helper type 2 cytokines (TNF, IL-12p40, IL-13) and chemokines (CCL3, CCL4, CCL20) in the NRL-allergic patients than in controls. Interestingly, mRNA expression of the regulatory cytokine TGF-beta1 was reduced, whereas IL-10 expression was enhanced after allergen stimulations in patients with NRL allergy. Finally, the NRL-allergic patients showed increased CCR4 expression on CD3(+)CD8(-) T cells and decreased CXCR3 expression on CD3(+)CD8(+) T cells. CONCLUSION: Allergen-specific induction of cytokines and chemokines in PBMC and chemokine receptor expression on circulating T cells may contribute to the pathogenesis of NRL allergy.

Repeated epicutaneous exposures to ovalbumin progressively induce atopic dermatitis-like skin lesions in mice.

BACKGROUND: Atopic dermatitis (AD) is a chronic skin disease in which environmental factors play a great role. A widely used murine model for AD has provided a useful tool to study the disease. OBJECTIVE: The purpose of this study is to investigate kinetically the induction of this AD model and the processes involved in the development of AD due to extrinsic allergen exposures. METHODS: BALB/c mice were epicutaneously exposed to ovalbumin (OVA) for 3 weeks; each week was separated by a 2-week resting period. Mice were killed after each exposure week. Skin biopsies and blood were obtained for histological study, RNA isolation and antibody analysis. RESULTS: There was a progressive and significant thickening of the epidermis and dermis in OVA-exposed mice. Significantly increased dermal cell infiltration of eosinophils, mast cells and total inflammatory cells, including CD3 and CD4 cells, was found after each OVA exposure week. Total IgE, IgG2a and OVA-specific IgE were significantly increased after the second and third exposure week, while OVA-specific IgG2a was significantly induced after the third exposure week. Gradual and/or significant increases in mRNA expression of IL-1beta, TNF-alpha, IL-4, IL-10, IL-13, IFN-gamma and IL-12p35 were found after each exposure week. Chemokines and their receptors involved in both T-helper type 1 (Th1)- and Th2-type cell recruitment (CCL1, CCL8, CCL11, CCL24, CXCL9, CXCL10, CCR1, CCR3, CCR5, CCR8 and CXCR3) were up-regulated significantly at different time-points. CONCLUSION: This study provides an insight into the dynamic nature and time-dependent transition of skin inflammation and systemic immune responses in a murine AD model induced by repeated epicutaneous exposures to OVA.

In vivo relationship between collagenase-2 and interleukin-8 but not tumour necrosis factor-alpha in chronic rhinosinusitis with nasal polyposis.

BACKGROUND: The characteristic feature of chronic rhinosinusitis with nasal polyposis (CRSwNP) is eosinophilic inflammation of the sinus mucosa; a type of inflammation also seen in asthmatic airways. Similar histopathologic findings of airway remodelling are present in both diseases. Remodelling is tightly controlled by matrix metalloproteinases (MMP). Increase of collagenase-2 (MMP-8) expression in the bronchial epithelial cells has been described in asthmatic patients, but it has not been studied in CRSwNP. METHODS: The concentrations and degree of activation of MMP-8 were analysed by immunofluorometric assay and Western blotting, respectively, in sinus mucus samples from CRSwNP patients and in nasal lavages from healthy controls in relation to inductive cytokines interleukin-8 (IL-8) and tumour necrosis factor-alpha (TNF-alpha). RESULTS: Significantly elevated levels of MMP-8 and IL-8 but not TNF-alpha were found in CRSwNP patients relative to controls. In particular, the activation of mesenchymal-type MMP-8 but not polymorphonuclear-type MMP-8 was associated with elevated IL-8 levels. CONCLUSIONS: The IL-8 and MMP-8 seemingly form an inductive cytokine-proteinase cascade in CRSwNP pathogenesis. Together they provide a target for novel therapies and a diagnostic tool for monitoring CRSwNP treatment.