Plasma Matrix Metalloproteinase Concentrations and Risk of Interstitial Lung Disease in a Prospective Rheumatoid Arthritis Cohort

OBJECTIVE

To evaluate the associations of plasma matrix metalloproteinases (MMPs) with prevalent and incident interstitial lung disease (ILD) in people with rheumatoid arthritis (RA).

METHODS

Within a multicenter, prospective cohort of US veterans with RA, we performed a cross-sectional study of prevalent ILD and cohort study of incident ILD. ILD diagnoses were validated by medical record review of provider diagnoses and chest imaging and/or pathology reports. MMP-1, 3, 7, and 9 concentrations were measured in plasma samples, then standardized and categorized into quartiles. The associations of MMPs with prevalent and incident ILD were assessed with logistic (prevalent) and Cox (incident) regression models adjusted for RA-ILD risk factors.

RESULTS

Among 2,312 participants (88.9% male; mean age 63.8 years), 96 had prevalent ILD. Incident ILD developed in 130 participants over 17,378 person-years of follow-up (crude incidence rate 7.5/1,000 person-years). Participants with the highest quartile of MMP-7 concentrations had a nearly four-fold increased odds of prevalent ILD (adjusted odds ratio 3.78 [95% confidence interval (95% CI) 1.86-7.65]) and over two-fold increased risk of incident ILD (adjusted hazard ratio 2.33 [95% CI 1.35-4.02]). Higher MMP-9 concentrations were also associated with prevalent and incident ILD, as well as negatively correlated with forced vital capacity among those with prevalent ILD (r = -0.30, P = 0.005).

CONCLUSION

MMP-7 and MMP-9 were strongly associated with both prevalent and incident ILD in this large, multicenter RA cohort after adjustment for other RA-ILD risk factors. These population-level findings further support a potential pathogenic role for MMPs in RA-ILD and suggest that their measurement could facilitate RA-ILD risk stratification.

Development and Internal Validation of a Clinical and Genetic Risk Score for Rheumatoid Arthritis-Associated Interstitial Lung Disease

OBJECTIVE

Although clinical and genetic risk factors have been identified for rheumatoid arthritis-associated interstitial lung disease (RA-ILD), there are no current tools allowing for risk stratification. We sought to develop and validate an ILD risk model in a large, multicentre, prospective RA cohort.

METHODS

Participants in the Veterans Affairs RA (VARA) registry were genotyped for 12 single nucleotide polymorphisms (SNPs) associated with idiopathic pulmonary fibrosis. ILD was validated through systematic record review. A genetic risk score (GRS) was computed from minor alleles weighted by effect size with ILD, using backward selection. The GRS was combined with clinical risk factors within a logistic regression model. Internal validation was completed using bootstrapping, and model performance was assessed by the area under the receiver operating curve (AUC).

RESULTS

Of 2,386 participants (89% male, mean age 69.5 years), 9.4% had ILD. Following backward selection, five SNPs contributed to the GRS. The GRS and clinical factors outperformed clinical factors alone in discriminating ILD (AUC 0.675 vs 0.635, p< 0.001). The shrinkage-corrected performance for combined and clinical-only models was 0.667 (95% CI 0.628, 0.712) and 0.623 (95% CI 0.584, 0.651), respectively. Twenty percent of the cohort had a combined risk score below a cut-point with >90% sensitivity.

CONCLUSION

A clinical and genetic risk model discriminated ILD in a large, multicentre RA cohort better than a clinical-only model, excluding 20% of the cohort from low-yield testing. These results demonstrate the potential utility of a GRS in RA-ILD and support further investigation into individualized risk stratification and screening.

Serum alarmins and the risk of incident interstitial lung disease in rheumatoid arthritis

OBJECTIVES

To quantify associations of serum alarmins with risk of rheumatoid arthritis-associated interstitial lung disease (RA-ILD).

METHODS

Using serum collected at enrolment, three alarmins (interleukin [IL]-33, thymic stromal lymphopoietin [TSLP], and IL-25) were measured in a multicentre prospective RA cohort. ILD was classified using systematic medical record review. Cross-sectional associations of log-transformed (IL-33, TSLP) or quartile (IL-25) values with RA-ILD at enrolment (prevalent RA-ILD) were examined using logistic regression, while associations with incident RA-ILD developing after enrolment were examined using Cox proportional hazards. Covariates in multivariate models included age, sex, race, smoking status, RA disease activity score, and anti-cyclic citrullinated antibody positivity.

RESULTS

Of 2,835 study participants, 115 participants (4.1%) had prevalent RA-ILD at baseline and an additional 146 (5.1%) developed incident ILD. There were no associations between serum alarmin concentrations and prevalent ILD in unadjusted or adjusted logistic regression models. In contrast, there was a significant inverse association between IL-33 concentration and the risk of developing incident RA-ILD in unadjusted (HR 0.73 per log-fold increase; 95% CI 0.57-0.95; p= 0.018) and adjusted (HR 0.77; 95% CI 0.59-1.00, p= 0.047) models. No significant associations of TSLP or IL-25 with incident ILD were observed.

CONCLUSIONS

In this study, we observed a significant inverse association between serum IL-33 concentration and the risk of developing incident RA-ILD, but no associations with prevalent ILD. Additional investigation is required to better understand the mechanisms driving this relationship and how serum alarmin IL-33 assessment might contribute to clinical risk stratification in patients with RA.

A Narrowing Mortality Gap: Temporal Trends of Cause-Specific Mortality in a National Matched Cohort Study in US Veterans With Rheumatoid Arthritis

OBJECTIVE

To examine temporal trends in all-cause and cause-specific mortality in patients with rheumatoid arthritis (RA) in the Veterans Health Administration (VHA).

METHODS

We conducted a matched cohort study in the VHA from January 1, 2000 to December 31, 2017. Incident RA patients were matched up to 1:10 on age, sex, and VHA enrollment year to non-RA patients, then followed until death or end of study period. Cause of death was obtained from the National Death Index. Multivariable Cox regression models stratified by RA diagnosis years were used to examine trends in RA-related risk of all-cause and cause-specific mortality.

RESULTS

Among 29,779 incident RA patients (matched to 245,226 non-RA patients), 9,565 deaths occurred. RA patients were at increased risk of all-cause (adjusted hazard ratio [HRadj ] 1.23 [95% confidence interval (95% CI) 1.20-1.26]), cardiovascular (HRadj 1.19 [95% CI 1.14-1.23]), cancer (HRadj 1.19 [95% CI 1.14-1.24]), respiratory (HRadj 1.46 [95% CI 1.38-1.55]), and infection-related mortality (HRadj 1.59 [95% CI 1.41-1.80]). Interstitial lung disease was the cause of death most strongly associated with RA (HRadj 3.39 [95% CI 2.88-3.99]). Nearly 70% of excess deaths in RA were attributable to cardiopulmonary disease. All-cause mortality risk related to RA was lower among those diagnosed during 2012-2017 (HRadj 1.10 [95% CI 1.05-1.15]) compared to 2000-2005 (HRadj 1.31 [95% CI 1.26-1.36]), but still higher than for non-RA controls (P < 0.001). Cause-specific mortality trends were similar.

CONCLUSION

Excess RA-related mortality was driven by cardiovascular, cancer, respiratory, and infectious causes, particularly cardiopulmonary diseases. Although our findings support that RA-related mortality risk is decreasing over time, a mortality gap remains for all-cause and cause-specific mortality in RA.

Genetic, social, and environmental risk factors in rheumatoid arthritis-associated interstitial lung disease

OBJECTIVE

MUC5B and TOLLIP single nucleotide polymorphisms (SNPs) and cigarette smoking were associated with rheumatoid arthritis-interstitial lung disease (RA-ILD) in a predominantly Northern European population. We evaluated whether RA-ILD is associated with these genetic variants and HLA-DRB1 shared epitope (SE) alleles in a large RA cohort stratified by race and smoking history.

METHODS

HLA-DRB1 SE alleles and MUC5B rs35705950 and TOLLIP rs5743890 SNPs were genotyped in U.S. veterans with RA. ILD was validated through medical record review. Genetic associations with ILD were assessed in logistic regression models overall and in subgroups defined by race and smoking status, with additive interactions assessed by the relative excess risk of interaction (RERI).

RESULTS

Of 2,556 participants (88% male, 77% White), 238 (9.3%) had ILD. The MUC5B variant was associated with ILD (OR 2.25 [95% CI 1.69, 3.02]), whereas TOLLIP and HLA-DRB1 SE were not. The MUC5B variant was less frequent among Black/African American participants (5.8% vs. 22.6%), though its association with RA-ILD was numerically stronger (OR 4.23 [1.65, 10.86]) compared to all other participants (OR 2.32 [1.70, 3.16]). Those with the MUC5B variant and a smoking history had numerically higher odds of ILD (OR 4.18 [2.53, 6.93]) than non-smokers (OR 2.41 [1.16, 5.04]). Additive interactions between MUC5B-race and MUC5B-smoking were not statistically significant.

CONCLUSION

In this large RA cohort, the MUC5B promoter variant was associated with >2-fold higher odds of RA-ILD. While this variant is less common among Black/African American patients, its presence in this population carried >4-fold higher odds of RA-ILD.

Adipocytokines and achievement of low disease activity in rheumatoid arthritis

PURPOSE

To determine if adipocytokines are independently associated with the achievement of low disease activity (LDA) over long-term follow-up in a large rheumatoid arthritis (RA) registry.

METHODS

This cohort study evaluated adults with RA from the Veteran's Affairs RA Registry. Adipocytokines (adiponectin, leptin, and fibroblast growth factor [FGF]-21) and inflammatory cytokines were measured as part of a multi-analyte panel on banked serum from enrollment. Covariates were derived from medical record, biorepository, and registry databases. Multivariable Cox proportional hazard models evaluated associations between adipocytokines and rates of 1) DAS28 LDA and remission, 2) individual Boolean remission criteria and 3) initiation of a new bDMARD or tsDMARD.

RESULTS

There were 1,276 participants with a DAS28 >3.2 at enrollment. Of these, 827 achieved LDA and 598 achieved remission over 2,287 and 4,096 person-years, respectively. Patients in the highest quartile of adiponectin had lower rates LDA before and after adjustment [aHR Q4: 0.68 (0.53,0.87) p<0.001]. Those in the highest quartile of leptin and FGF-21 also had lower rates of LDA. Higher quartiles of adipocytokines were also associated with lower rates of achieving a low patient/evaluator global scores and low tender joint counts. Among 1,236 biologic-naïve participants, values above the median for adiponectin [HR: 1.67 (1.23,1.26) p = 0.001] and FGF-21 [HR: 1.27 (1.09,1.47) p = 0.002] were associated with a greater likelihood of initiating a b/tsDMARD.

CONCLUSIONS

Adipocytokines may serve as prognostic biomarkers of a more severe RA disease course. Additional study is needed to determine whether adipocytokines are phenotypic markers or whether they actively promote disease progression.

The impact of disease severity measures on survival in U.S. veterans with rheumatoid arthritis-associated interstitial lung disease

OBJECTIVES

To determine whether RA and interstitial lung disease (ILD) severity measures are associated with survival in patients with RA-ILD.

METHODS

We studied US veterans with RA-ILD participating in a multicentre, prospective RA cohort study. RA disease activity (28-joint DAS [DAS28-ESR]) and functional status (multidimensional HAQ [MDHAQ]) were collected longitudinally while pulmonary function tests (forced vital capacity [FVC], diffusing capacity for carbon monoxide) were obtained from medical records. Vital status and cause of death were determined from the National Death Index and administrative data. Predictors of death were assessed using multivariable Cox regression models adjusting for age, sex, smoking status, ILD duration, comorbidity burden and medications.

RESULTS

We followed 227 RA-ILD participants (93% male and mean age of 69 years) over 1073 person-years. Median survival after RA-ILD diagnosis was 8.5 years. Respiratory diseases (28%) were the leading cause of death, with ILD accounting for 58% of respiratory deaths. Time-varying DAS28-ESR (adjusted hazard ratio [aHR] 1.21; 95% CI: 1.03, 1.41) and MDHAQ (aHR 1.85; 95% CI: 1.29, 2.65) were separately associated with mortality independent of FVC and other confounders. Modelled together, the presence of either uncontrolled disease activity (moderate/high DAS28-ESR) or FVC impairment (<80% predicted) was significantly associated with mortality risk. Those with a combination of moderate/high disease activity and FVC <80% predicted had the highest risk of death (aHR 4.43; 95% CI: 1.70, 11.55).

CONCLUSION

Both RA and ILD disease severity measures are independent predictors of survival in RA-ILD. These findings demonstrate the prognostic value of monitoring the systemic features of RA-ILD.

Elevations in adipocytokines and mortality in rheumatoid arthritis

OBJECTIVES

This study assessed whether circulating levels of adiponectin and leptin are associated with higher mortality in patients with RA.

METHODS

Participants were adults from the Veterans Affairs RA Registry. Adipokines and inflammatory cytokines were measured as part of a multi-analyte panel on banked serum at enrolment. Dates and causes of death were derived from the Corporate Data Warehouse and the National Death Index. Covariates were derived from medical record, biorepository and registry databases. Multivariable Cox proportional hazard models evaluated associations between biomarkers and all-cause and cause-specific mortality.

RESULTS

A total of 2583 participants were included. Higher adiponectin levels were associated with older age, male sex, white race, lower BMI, autoantibody seropositivity, radiographic damage, longer disease duration, prednisone use and osteoporosis. Higher adiponectin concentrations were also associated with higher levels of inflammatory cytokines but not higher disease activity at enrolment. Leptin was primarily associated with greater BMI and comorbidity. The highest quartile of adiponectin (vs lowest quartile) was associated with higher all-cause mortality [hazard ratio (HR): 1.46 (95% CI: 1.11, 1.93), P = 0.009] and higher cardiovascular mortality [HR: 1.85 (95% CI: 1.24, 2.75), P = 0.003], after accounting for covariates. Higher leptin levels were also associated with greater all-cause and cancer mortality.

CONCLUSIONS

Elevations in adipokines are associated with age, BMI, comorbidity and severe disease features in RA and independently predict early death. Associations between adiponectin and inflammatory cytokines support the hypothesis that chronic subclinical inflammation promotes metabolic changes that drive elevations in adipokines and yield adverse health outcomes.

Optical Photothermal Infrared Microspectroscopy with Simultaneous Raman - A New Non-Contact Failure Analysis Technique for Identification of <10 μm Organic Contamination in the Hard Drive and other Electronics Industries

Optical Photothermal Infrared (O-PTIR) spectroscopy is a new technique for measuring submicron spatial resolution IR spectra with little or no sample preparation. This speeds up analysis times benefiting high-volume manufacturers through gaining insight into process contamination that occurs during development and on production lines. The ability to rapidly obtain far-field non-contact IR spectra at high spatial resolution facilitates the chemical identification of small organic contaminants that are not possible to measure with conventional Fourier transform infrared (FT-IR) microspectroscopy. The unique pump-probe system architecture also facilitates submicron simultaneous IR + Raman microscopy from the same spot with the same spatial resolution. With these unique capabilities, O-PTIR is finding utilization in the high-volume and high-value industries of high-tech componentry (memory storage, electronics, displays, etc.).

Exposure to ambient air pollution and autoantibody status in rheumatoid arthritis

OBJECTIVE

To evaluate the relationship between air pollutant (AP) exposure and rheumatoid arthritis (RA) autoantibody status METHODS: We performed a cross sectional study utilizing enrollment data from participants in the Veterans Affairs rheumatoid arthritis registry. HLA-DRB1 shared epitope (SE), smoking, rheumatoid factor (RF), and anti-cyclic citrullinated peptide antibody (ACPA) status were collected. Mean exposure levels were obtained for AP (NO₂, SO₂, particulate matter [PM_2.5, PM₁₀], and ozone) from air quality monitoring stations at patients' residential zip codes in the year prior to enrollment. Multivariable logistic and ordinary least squares regression models were used to determine independent associations of AP with RA seropositivity and autoantibody concentration.

RESULTS

The cohort included 557 veterans (90% male, 76% Caucasian), with mean age of 70 years and mean disease duration of 13 years. The majority were HLA-DRB1 SE, RF, and ACPA positive (73%, 79%, and 76%, respectively). In univariate models, PM_2.5 exposure was associated with higher ACPA concentration (p = 0.009). Similarly, in multivariable regression models, PM_2.5 exposure was independently associated with higher ACPA concentration (p = 0.037). Current smoking independently predicted RF and ACPA positivity and titers, while HLA-DRB1 SE alleles were associated with RF positivity and ACPA positivity and titers.

CONCLUSIONS

In an elderly cohort of RA patients, fine particulate matter (PM_2.5) exposure independently predicted higher ACPA concentration. Further study of fine particulate matter in the pathogenesis of RA is warranted. Key Points • A study that integrates both genetic and environmental exposure data, relative to RA autoantibody status. • Of different air pollutants measures, exposure to fine particulate matter (PM_2.5) appears to be most closely linked to ACPA titers.

Therapies for active rheumatoid arthritis after methotrexate failure

BACKGROUND

Few blinded trials have compared conventional therapy consisting of a combination of disease-modifying antirheumatic drugs with biologic agents in patients with rheumatoid arthritis who have active disease despite treatment with methotrexate--a common scenario in the management of rheumatoid arthritis.

METHODS

We conducted a 48-week, double-blind, noninferiority trial in which we randomly assigned 353 participants with rheumatoid arthritis who had active disease despite methotrexate therapy to a triple regimen of disease-modifying antirheumatic drugs (methotrexate, sulfasalazine, and hydroxychloroquine) or etanercept plus methotrexate. Patients who did not have an improvement at 24 weeks according to a prespecified threshold were switched in a blinded fashion to the other therapy. The primary outcome was improvement in the Disease Activity Score for 28-joint counts (DAS28, with scores ranging from 2 to 10 and higher scores indicating more disease activity) at week 48.

RESULTS

Both groups had significant improvement over the course of the first 24 weeks (P=0.001 for the comparison with baseline). A total of 27% of participants in each group required a switch in treatment at 24 weeks. Participants in both groups who switched therapies had improvement after switching (P<0.001), and the response after switching did not differ significantly between the two groups (P=0.08). The change between baseline and 48 weeks in the DAS28 was similar in the two groups (-2.1 with triple therapy and -2.3 with etanercept and methotrexate, P=0.26); triple therapy was noninferior to etanercept and methotrexate, since the 95% upper confidence limit of 0.41 for the difference in change in DAS28 was below the margin for noninferiority of 0.6 (P=0.002). There were no significant between-group differences in secondary outcomes, including radiographic progression, pain, and health-related quality of life, or in major adverse events associated with the medications.

CONCLUSIONS

With respect to clinical benefit, triple therapy, with sulfasalazine and hydroxychloroquine added to methotrexate, was noninferior to etanercept plus methotrexate in patients with rheumatoid arthritis who had active disease despite methotrexate therapy. (Funded by the Cooperative Studies Program, Department of Veterans Affairs Office of Research and Development, and others; CSP 551 RACAT ClinicalTrials.gov number, NCT00405275.)

Anti-inflammatory properties of montelukast, a leukotriene receptor antagonist in patients with asthma and nasal polyposis

BACKGROUND

Leukotrienes, especially LTC4, are important inflammatory mediators in allergic and nonallergic inflammation of the entire airways. Of particular interest are numerous theories regarding the pathogenesis of aspirin intolerance with subsequent hyperproduction of leukotrienes and inhibition of cyclooxygenase.

OBJECTIVE

To examine the influence of the cysteinyl-leukotriene receptor antagonist montelukast on clinical symptoms and inflammatory markers in nasal lavage fluid in patients with bronchial asthma and nasal polyps, and determine its dependency on aspirin sensitization.

METHODS

Twenty-four patients (7 women, 17 men; median age, 55.5 years) with nasal polyps and controlled asthma (n=12 with aspirin intolerance) were treated with 10 mg montelukast once daily for 6 weeks in a blinded, placebo-controlled fashion. The placebo phase was randomly assigned 4 weeks before (n=12) or after treatment (n=12). Symptom score, rhinoendoscopy, rhinomanometry, smears for eosinophils, and nasal lavages for the determination of different mediators were performed.

RESULTS

Compared to placebo, there were significant improvements in the nasal symptom score and airflow limitation as well as a reduction in the inflammatory mediators in nasal lavage fluid after treatment. Furthermore, reduced eosinophils in nasal smears and peripheral blood were observed 2 and 6 weeks after treatment.

CONCLUSION

Leukotriene 1 receptor blockade led to a significant decrease in eosinophil inflammation accompanied by a reduction in other mediators such as neurokinin A and substance P in the nasal lavage fluid of patients with nasal polyps and asthma, with or without aspirin intolerance.

Leflunomide in the treatment of rheumatoid arthritis

Rheumatoid arthritis is a chronic and highly morbid disease affecting approximately 1% of the world's population. With the advent of disease-modifying antirheumatic drugs, patients are increasingly able to maintain control of their arthritis and prevent joint destruction. However, not all patients respond adequately to any single disease-modifying antirheumatic drug, and many newer parenteral therapies are cost prohibitive. Leflunomide, an inhibitor of pyrimidine biosynthesis, is the first oral disease-modifying antirheumatic drug to have been approved for rheumatoid arthritis in the USA in the last 15 years, and is now widely used in over 70 countries around the world. Leflunomide is efficacious when used as monotherapy or in combination with methotrexate to treat patients with rheumatoid arthritis, and is generally well tolerated. As clinical use increases, new ways to use leflunomide in order to minimize toxicity and maximize efficacy are being explored.

Effect of fluticasone on neuropeptides in nasal lavage in persistent allergic rhinitis

OBJECTIVE

Recent guidelines reveal that allergic rhinitis impairs quality of life. Neuropeptides play a central role in allergy-related nasal inflammation. The objective of this study was to analyze the release of neuropeptides (substance P, neurokinin A, and vasoactive intestinal peptide) in nasal lavage and their modification by intranasal fluticasone propionate as an established therapy in patients with allergic rhinitis.

METHODS

Eleven patients with proven allergic rhinitis induced by house dust mite were challenged before and after administration of fluticasone propionate nasal spray. Nasal lavage samples were collected after allergen challenge, and neuropeptides were measured using enzyme-linked immunosorbent assay. Values for histamine, protein, and human serum albumin were also recorded. Eight healthy individuals were included as nonatopic controls.

RESULTS

The neuropeptides investigated were detectable in nasal lavage fluid in both patients and controls. Treatment with fluticasone propionate significantly decreased clinical response to allergen challenge (P < .01) compared with the controls and led to a decrease in values for substance P, neurokinin A, vasoactive intestinal peptide, histamine release, human serum albumin, and total protein after allergen challenge (P < .01).

CONCLUSIONS

The demonstration of proinflammatory neuropeptides in NAL and suppression of their release after allergen challenge caused by a topical corticosteroid suggest a role for neuropeptides in allergic inflammation. Diminished release of neuropeptides induced b fluticasone propionate was accompanied by an improvement in the clinical symptoms of patients with persistent allergic rhinitis.

Effects of fexofenadine on inflammatory mediators in nasal lavage fluid in intermittent allergic rhinitis

OBJECTIVE

Allergic rhinitis, a disease that impairs quality of life, is characterized by inflammation due to an allergic reaction. Fexofenadine is a second-generation histamine receptor blocker well known for its potent interaction with this inflammatory process. The main aim of this study was to further clarify the anti-inflammatory effects exerted by fexofenadine in patients with intermittent allergic rhinitis.

METHODS

Twenty patients with intermittent allergic rhinitis due to birch and mugwort pollen were enrolled. Fexofenadine was administered once a day at a dose of 120 mg. Clinical improvement was assessed by a symptom score, and nasal airway flows were measured by anterior rhinomanometry at baseline and after 2 weeks of treatment with fexofenadine. Nasal smears were tested for eosinophils and nasal lavage fluid were examined for histamine, cysteinyl leukotrienes, soluble intercellular adhesion molecule-1, eosinophil cationic protein, and albumin by enzyme-linked immunosorbent assay. All the tests were performed during the pollen season.

RESULTS

Fexofenadine induced a significant improvement in nasal and ocular symptoms (P < .001), nasal edema and secretion (P < .001), and nasal airway flow (P < .001). The clinical improvement was related to a significant reduction in all inflammatory mediators (P < .01 in all cases).

CONCLUSION

This study demonstrates that fexofenadine is able to mediate significant changes in different nasal lavage markers from patients with intermittent allergic rhinitis. The changes observed in the markers analyzed in both nasal secretions and serum are attributable to the anti-inflammatory effects of fexofenadine in vivo.

Direct detection of bacterial genomic DNA using gold nanoparticle probes

The molecular probes and associated instrumentation necessary to perform genetic analyses are typically expensive, complex, and prone to error. While techniques such as real-time polymerase chain reaction (PCR) and gene expression analysis have provided a wealth of information previously unattainable, their utility in clinical diagnostics has yet to be realized due to the aforementioned limitations. Nanosphere Inc. has developed a gold nanoparticle-based platform for sequence specific DNA detection that is well-suited for clinical diagnostics due to its cost-effectiveness, simplicity, and accuracy. Thirteen nanometer gold nanoparticle probes, stabilized by a shell of oligonucleotides using proprietary attachment chemistries, enable highly sensitive and specific detection of bacterial genomic DNA sequences without synthetic amplification techniques on a glass array. After silver staining, light scattered by the nanoparticle probes is collected with robust, cost-effective instrumentation. It is the unique features of Nanosphere's detection methodology that provide the necessary steps forward to allow for genetic analyses to become part of routine clinical diagnostics.

Efficacy and safety of formoterol delivered through the Novolizer, a novel dry powder inhaler (DPI) compared with a standard DPI in patients with moderate to severe asthma

BACKGROUND & OBJECTIVE

Because of environmental concerns CFC-containing pressurised metered dose inhalers (pMDI) had to be replaced by dry powder inhalers (DPI). The Novolizer, a novel DPI has previously been shown to be as effective as the Turbuhaler in delivering budesonide. The objective of this study was to show non-inferiority of inhaled formoterol therapy delivered through the Novolizer compared to formoterol delivered through the Aerolizer in patients suffering from moderate to severe asthma.

METHODS

In this double-blind, double-dummy, multicentre study 392 patients were randomised and received a dose of 12 microg formoterol twice daily for 4 weeks either through the Aerolizer or the Novolizer. FEV1 after 4 weeks of treatment was the primary variable. Secondary variables were FVC, PEF, consumption of short-acting; 2 adrenoceptor agonists, asthma symptoms, tolerability and safety.

RESULTS

After 4 weeks of treatment, the mean trough FEV1 (95% CI) was 2.34 L (2.24-2.45) for the Novolizer and 2.31 L (2.21-2.41) for the Aerolizer. Non-inferiority was proven (p<0.0001, pre-defined; of 0.25 L). All secondary variables (incl. PEF) confirmed these findings. Treatment with both devices was safe and well tolerated.

CONCLUSION

Inhalation of 12 microg formoterol twice daily via Novolizer was shown to be equally therapeutically effective compared to the inhalation via Aerolizer in the treatment of moderate to severe persistent asthma. Treatment via both inhalers was safe and well tolerated.

Omalizumab decreased IgE-release and induced changes in cellular immunity in patients with allergic asthma

BACKGROUND

Omalizumab, a recombinant monoclonal anti-immunoglobulin E (IgE) antibody, shows proven efficacy in the treatment of allergic diseases. A little is known about the immunological pathways affected by the decrease of circulating free IgE during omalizumab treatment.

AIM OF THE STUDY

To investigate the immunological consequence of IgE withdrawal, we studied the influence of omalizumab on stimulated IgE-release of cultured peripheral blood mononuclear cells (PBMC) and on the relative number of lymphocytes in the peripheral blood (cellular immune status) in patients with allergic asthma.

METHODS

Nineteen patients were enrolled and received omalizumab at a dose of at least 0.016 mg/kg/IgE (IU/ml) every 4 weeks. PBMC were isolated from peripheral blood. Cells were cultured and stimulated with IL-4 (5 ng/ml) and CD40 ligand (1 microg/ml) for 10 days. IgE release was detected in cell culture supernatants by enzyme-linked immunosorbent assay (ELISA). Cellular immune status was investigated by fluorescence-activated cell sorting.

RESULTS

Omalizumab treatment induced significant inhibition of stimulated IgE release (median 1.38-0 ng/ml vs. 1.64-2.0 ng/ml in placebo group, P<0.05). B-lymphocyte counts were also significantly lower in the omalizumab group compared with placebo after 12 weeks of treatment (median 18.2-15.6% lymphocytes vs 12.7-13.7% lymphocytes after placebo, P<0.01). There were no significant differences in the other lymphocyte subpopulations between the groups.

CONCLUSIONS

These findings provide evidence of immunological influences of omalizumab treatment, leading to a downregulation of IgE secretion and decrease of lymphocyte subpopulations (B-cells) indicating their anti-inflammatory potency.

Use of CD34+ autologous stem cell transplantation in the treatment of children with refractory systemic lupus erythematosus

We report on the unique effects and benefits of autologous stem cell transplantation in childhood systemic lupus erythematosus (SLE) and describe this procedure in two young girls with severe and refractory disease. The patients' stem cells were mobilized with granulocyte colony-stimulating factor (G-CSF) and collected by CS-3000 Blood Cell Separator (Baxter Healthcare, Round Lake, Ill., USA), and the CliniMACS CD34+ cell selection device (Miltenyi Biotech, Bergisch Gladbach, Germany) was used to obtain CD34+ cells. A total of 1.7x10(6) and 1.0x10(6)/kg CD34+ cells were obtained, with 2.0x10(5) and 1.0x10(4)/kg of CD3+ cells remaining, respectively. The conditioning regimen consisted of cyclophosphamide (50 mg/kg per day for 4 days) plus antithymocyte globulin (ATG-Fresenius, 5 mg/kg per day for 3 days). Neutrophil counts recovered within 9 days in both cases. Within 15 days, the platelet counts recovered and were sustained over 100x10(9)/l. Cushingoid features disappeared completely 3 months after transplantation because of the removal of corticosteroid medication. One 13-year-old child increased her height by 5 cm in 6 months after stopping steroids. She had not increased her height in her previous 7 years of disease. As of the time of this report, the first patient remains in clinical and laboratory remission for nearly 4 years, while the second suffered a relapse of thrombocytopenia 9 months post-transplantation. One residual effect of their treatment is that their CD4+ cell counts remained in the lower range after one year of transplant. The effect of this conditioning regimen plus CD34+ autologous stem cell transplantation on these two children with refractory SLE was beneficial, but long-term follow-up data and additional experience with this procedure are required. Autologous stem cell transplantation may limit the long-term toxicity of therapy in childhood SLE.

Omalizumab inhibits allergen challenge-induced nasal response

Elevated serum levels of antigen-specific immunoglobulin (Ig)E are often associated with allergic respiratory diseases. This parallel-group, randomised, double-blind, placebo-controlled trial was designed to study the influence of omalizumab on the early nasal response to allergen challenge reflected by symptom score and inflammatory marker levels in nasal lavage fluid (NAL). A total of 23 patients with allergic rhinitis took part in the study, 11 were given placebo and omalizumab was administered subcutaneously in 12. Omalizumab or placebo were given at 2- or 4-week intervals based on a patient's body weight and IgE levels to a total dose of 0.016 mg x kg(-1) x IgE(-1) (IU x mL(-1)) every 4 weeks. Compared to placebo, 16 weeks of treatment with omalizumab significantly inhibited allergen challenge-induced nasal symptoms (median symptom score 7.0-0.5 versus 7.0-7.0) and inhibited the increase of human serum albumin (median 15.3-0.12 mg x mL(-1) versus 8.2-19.7 mg x mL(-1)) in the NAL after allergen challenge. Treatment with omalizumab induced a significant decrease in tumour necrosis factor-alpha levels in basal NAL, but no change was seen for histamine. These results indicate that subcutaneously administered monoclonal anti-immunoglobulin-E antibody, omalizumab, inhibits the nasal responses to allergen challenge of patients with allergic rhinitis. Omalizumab may provide a new strategy for the treatment of allergic rhinitis.

Efficacy, safety, and acceptance of beclomethasone dipropionate administered via a new dry powder Inhaler or a standard CFC metered-dose inhaler in asthma patients

BACKGROUND/OBJECTIVES

The mechanical aerosol generator, MAGhaler, is a new chlorofluorocarbon-free inhalation device. The objective of this trial was to show equivalent efficacy and safety of beclomethasone dipropionate (BDP) delivered via the MAGhaler and the metered-dose inhaler (MDI) in patients with mild to moderate bronchial asthma. Moreover, user-friendliness and acceptance of the two devices were compared.

METHODS

This was a double-blind, reference-controlled, 12-week trial in 171 patients with asthma receiving BDP (1,000 microg/day) delivered via either the MAGhaler or the conventional MDI. Respiratory function parameters, clinical symptoms, concomitant intake of salbutamol or fenoterol, adverse events (AEs), laboratory values, and concomitant medications and diseases were recorded. The primary efficacy parameter was mean forced expiratory volume in 1 s (FEV1), measured after 4, 8, and 12 weeks of therapy.

RESULTS

The equivalence of the two devices was confirmed (p = 0.003) on the basis of the ratios of the mean FEV1 in weeks 4 to 12. Mean (+/- SD) FEV1 (MAGhaler was 2.24 +/- 0.60 l (baseline), 2.61 +/- 0.90 litres (week 4), and 2.62 +/- 0.87 litres (weeks 4-12). Mean FEV1 (MDI) was 2.28 +/- 0.59 litres (baseline), 2.53 +/- 0.82 litres (week 4), and 2.56 +/- 0.77 litres (weeks 4-12). In total, 33 AEs occurred in 26 (30.2%) patients (MAGhaler) and 51 AEs in 36 (42.4%) patients (MDI). Most of the AEs were of mild or moderate intensity. The relationship to treatment could not be excluded for 11 AEs in 11 patients (MAGhaler) and 23 AEs in 18 patients (MDI). Three serious AEs, all unrelated to treatment, occurred in 3 patients (MAGhaler: 2, MDI: 1). There were no clinically relevant changes in other safety parameters. Most patients either preferred the MAGhaler or rated the two devices as equally acceptable.

CONCLUSION

The new MAGhaler was equivalent to the standard MDI in terms of the safety and efficacy of BDP. The improved user-friendliness and acceptance of the MAGhaler over the conventional MDI represent an important advance in the clinical management of bronchial asthma.

The production, storage and release of the neurotrophins nerve growth factor, brain-derived neurotrophic factor and neurotrophin-3 by human peripheral eosinophils in allergics and non-allergics

BACKGROUND

Recent studies have shown that neurotrophins are produced by and can act on several immune-inflammatory cells. The origin of circulating as well as local neurotrophins is unknown.

OBJECTIVES

The aim of this study was to assess whether eosinophils of allergic and non-allergic donors produce, store and release the neurotrophic factors NGF, BDNF and NT-3.

METHODS

Eosinophils were purified by negative immunoselection (purity > 96%) from allergic asthmatics and non-allergic donors (25 to 53 years). The presence of mRNA for neurotrophic factors was evaluated by reverse transcription PCR. Specificity was demonstrated by cloning products and sequencing. Stored NGF, BDNF and NT-3 was demonstrated by Western-blotting and flow cytometry. Eosinophils were incubated and supernatants were collected for measurement of neurotrophic factors after cell stimulation with PAF. Neurotrophin content in eosinophil lysates was determined by ELISA.

RESULTS

Eosinophils demonstrate mRNA for neurotrophins. Proteins were detectable by Western blot and FACS analysis. Neurotrophins were found in the eosinophil lysates at different amounts comparing allergic and non-allergic donors. Cell stimulation with PAF (10-8-10-5 M) after priming with GM-CSF leads to a dose-dependant release of NGF and BDNF.

CONCLUSIONS

Eosinophils store, produce and release NGF, BDNF and NT-3. They are a possible source of elevated neurotrophin levels found in allergy and asthma.

Monoclonal anti-interleukin-5 treatment suppresses eosinophil but not T-cell functions

Influx of eosinophils in airway mucosa and airway lumen is a hallmark of bronchial asthma. In-vitro data and animal studies indicate that the T-helper (Th) type-2 cell cytokine, interleukin (IL)-5, plays an important role in eosinophil maturation, differentiation, recruitment, and survival. The objective of this study was to determine whether intravenous treatment with monoclonal anti-IL-5 would affect the number of peripheral blood eosinophils, their activation status, T-cell activation or the pattern of Th1 and Th2 cytokine production. Over a period of 6 months, 19 asthmatics were investigated in a double-blind, placebo-controlled, multicentre study with mepolizumab (SB 240563) anti-IL-5 antibody administered three times. Before each infusion and 12 weeks after the last infusion, peripheral blood leukocytes were examined, qualitative and quantitative distribution of eosinophils and lymphocyte subpopulations, frequencies of IL-2, -3, -4, -5, -10, -13, interferon-gamma-producing CD4 T-cells and serum eosinophil cationic protein (ECP) levels were determined. Treatment with mepolizumab resulted in a marked, rapid and sustained decrease of eosinophil numbers (median values from 300 to 45 per microL) paralleled by decreased levels of serum ECP (median values from 15 to 5 microg x L(-1)). Distribution of T-cell subsets and T-cell cytokine production were not altered during antibody treatment. In conclusion, administration of mepolizumab to asthmatic patients markedly reduces peripheral blood eosinophils without altering the distribution and activation status of lymphocytes.

Antioxidative enzymes in human nasal mucosa after exposure to ozone. Possible role of GSTM1 deficiency

OBJECTIVE AND DESIGN

Epithelial antioxidative enzymes (AOEs) are thought to be a first line of defense against reactive oxygen species as they are upregulated after exposure to ozone according to animal studies. We analysed the activities of the AOEs catalase (CAT), glutathione peroxidase (GPX), glutathione reductase (GR), superoxide dismutase (SOD) and glutathione-S-transferase (GST) in a tissue culture of human nasal mucosa and analysed the influence of GSTM1 polymorphism on AOE regulation.

METHODS

Tissue biopsies of 20 subjects were incubated for 24 h with and without 120 ppb ozone. Activities were assayed to determine what enzymatic changes had taken place, both overall and in regard to GSTM1 status.

RESULTS

Activities for GPX (p = 0.272) and SOD (p = 0.291) were found increased after ozone exposure. GSTM1-deficient patients showed a significantly enhanced upregulation of SOD activity (p = 0.011) compared to GSTM1 carriers.

CONCLUSION

Our findings suggest that GSTM1-deficiency has an impact on AOE-regulation after ozone exposure.

Immunoblot studies in birch pollen-allergic patients with and without fruit hypersensitivity: part I: antibody pattern for birch pollen extract

About 40-70% of birch pollen allergic patients show allergic symptoms after ingesting or handling raw fruits. Several investigations have indicated a partial immunological identity between birch pollen and stone fruit. To further clarify this association, we investigated 59 patients with allergic symptoms (conjunctivitis, rhinitis, and asthma during the birch pollen season) and 18 nonatopic controls by skin prick test (SPT) and RAST with birch pollen, fresh apple, cherry, and peach as well as freshly prepared fruit extracts. According to a questionnaire dealing with symptoms after ingestion of raw fruits, the subjects were divided into groups with (35 FH+) and without (24 FH-) fruit hypersensitivity. IgE, IgG, IgG1, IgG4, IgA, and IgM binding patterns to birch pollen extracts were performed with 33 sera (12 FH+, 11 FH-, and 10 nonatopic controls) using the immunoblot-technique. Patients with FH+ expressed a significantly stronger sensitization to birch pollen than patients without FH-, as measured by RAST and SPT. Native fruits induced stronger SPT reactions than fruit extracts, and patients with FH+ showed a significantly higher skin index with all fruits and fruit extracts tested. Specific IgE, IgG, IgG1, IgG4, IgM and IgA to birch pollen extracts could be detected by immunoblot in all groups, albeit with different frequencies and intensities. From this data we conclude that fruit hypersensitivity is related more to the 17 kd and 67-85 kd than to the 26-28 kd or 36 kd protein bands of the birch pollen extract. The relationship of specific IgE > IgG > IgM to a single protein band seems to be associated with the development of symptomatic type I allergy.

Immunoblot studies in birch pollen-allergic patients with and without fruit hypersensitivity: part II: antibody pattern for fruit extracts

Patients allergic to birch pollen also exhibit more hypersensitivity reactions to fresh fruits and vegetables than do patients allergic to other pollens. Several investigations have indicated a possible partial immunological identity between birch pollen and fruits. To study this, 23 birch pollen-allergic patients 12 with (FH+) and 11 without (FH-) fruit hypersensitivity and 10 nonatopic controls were examined with self-prepared apple-peel, cherry, and peach extracts by immunoblotting. The self-prepared extracts were characterized by histamine release studies with 20 FH+ birch pollen-allergic patients. Specific IgE, IgG, IgG1, IgG4, IgA, and IgM binding patterns of the fruit extracts presented an individual distribution with at least 1-3 IgE bands at varying molecular weight locations. The FH+ group expressed intense IgE binding to the different extracts compared to the FH- group, and even the control group showed all immunoglobulin classes, though different frequencies and intensities compared to the allergic groups. It seemed that the specific IgE > IgG > IgM relation to a single antigen is important for distinguishing between symptomatic and asymptomatic persons. With this hypothesis we found most IgE with less IgG binding to apple-peel in the region of 22-28 kd and 43-56 kd, cherry: 15-25 kd and 72- > 90 kd and peach 35-41 kd and 66-76 kd, suggesting that these proteins might be important for cross-reactivity with birch pollen and developing fruit hypersensitivity.

Activation of the specific neurotrophin receptors TrkA, TrkB and TrkC influences the function of eosinophils

BACKGROUND

Recent studies have shown that nerve growth factor (NGF) can act on several immune cells as well as residential cells. But little is known about their role in modulating eosinophil function via activation of high-affinity receptors.

OBJECTIVES

The aim of this study was to assess whether eosinophils express functional receptors and if their function is influenced by NGF, brain-derived neurotrophic factor (BDNF) or neurotrophin-3 (NT-3).

METHODS

Eosinophils were purified by negative immunoselection (purity > 96%). High-affinity neurotrophin receptors were demonstrated by reverse transcription polymerase chain reaction, western blotting and flow-cytometry analysis. Functionality of receptors was demonstrated by receptor phosphorylation after ligand binding. Eosinophils were incubated with NGF, BDNF and NT-3, and cells and supernatants were collected for measurement of the mediators IL-4, IL-5, IL-8, transforming growth factor (TGF)-beta1, eosinophil cationic protein (ECP), eosinophil protein X (EPX) as well as eosinophil viability.

RESULTS

Eosinophils expressed mRNA for neurotrophin receptors. Proteins were detectable by western blot and fluorescent-activated cell sorter analysis. The receptors were phosphorylated after stimulation with neurotrophins. After NGF stimulation, a significant increase in IL-4 was detectable. BDNF and NT-3 stimulation led to a significant increase in EPX. Eosinophil viability was not influenced.

CONCLUSIONS

Eosinophils express the functionally active receptors TrkA, TrkB and TrkC. Receptor activation stimulates eosinophils. This might be an additional pathway regulating inflammatory responses in allergic reactions.

Effects of beta-endorphin on nasal allergic inflammation

BACKGROUND

Beta-endorphin is a derivative of pro-opiomelanocortin. Cells of the immune system can also synthesize and secrete beta-endorphin. Its concentration is increased during the allergic reaction and during stress. Increased reactivity during psychological stress of allergic subjects is also well known.

OBJECTIVE

Is beta-endorphin one physiological link between stress and an exacerbation of the allergic reaction?

METHODS

First, intranasal beta-endorphin challenges with subsequent lavages to determine histamine and albumin levels and measurements of nasal flow and resistance in dose-response and time course experiments were performed. Secondly, we examined whether beta-endorphin pre-treatment increased the antigen-induced release of histamine and albumin in nasal lavages and the clinical symptoms.

RESULTS

Exogenous beta-endorphin (100 pM-10 microM/mL) induced a dose-dependent increase in nasal symptoms in asymptomatic allergic subjects with rhinitis (n = 14) as well as in non-allergic controls (n = 10), but did not release any mediators into nasal secretion. However, comparing the antigen-evoked release of mediators into nasal secretions with that of a beta-endorphin pre-treated antigen challenge we could note a significant enhancement of human serum albumin influx (P < 0.05) and histamine liberation (P < 0.05) 10 min after antigen challenge compared with the allergen challenge alone, with also a correlation with the more pronounced decrease in nasal flow (P < 0.05).

CONCLUSION

These results suggest that beta-endorphin-induced increase in nasal congestion is mediated through direct neuroendocrine receptor activation independent of mast cell activation and that during the allergic reaction there is a beta-endorphin/mast cell interaction that enhances the mediator response to nasal allergen challenge.

The novel zinc finger-containing transcription factor osterix is required for osteoblast differentiation and bone formation

We have identified a novel zinc finger-containing transcription factor, called Osterix (Osx), that is specifically expressed in all developing bones. In Osx null mice, no bone formation occurs. In endochondral skeletal elements of Osx null mice, mesenchymal cells, together with osteoclasts and blood vessels, invade the mineralized cartilage matrix. However, the mesenchymal cells do not deposit bone matrix. Similarly, cells in the periosteum and in the condensed mesenchyme of membranous skeletal elements cannot differentiate into osteoblasts. These cells do, however, express Runx2/Cbfa1, another transcription factor required for bone formation. In contrast, Osx is not expressed in Runx2/Cbfa1 null mice. Thus, Osx acts downstream of Runx2/Cbfa1. Because Osx null preosteoblasts express typical chondrocyte marker genes, we propose that Runx2/Cbfa1-expressing preosteoblasts are still bipotential cells.

The influence of inhalative corticosteroids on circulating Nerve Growth Factor, Brain-Derived Neurotrophic Factor and Neurotrophin-3 in allergic asthmatics

BACKGROUND

The neurotrophins Nerve Growth Factor (NGF), Brain-Derived Neurotrophic Factor (BDNF) and Neurotrophin (NT)-3 are produced, stored and released by various immunological cells. The influence of NTs upon the function of these cells is described. Elevated plasma levels were found in inflammatory, autoimmune and allergic diseases with the highest levels in allergic asthma. A connection between bronchial hyper-responsiveness and serum levels has been reported.

OBJECTIVE

Little is known about the influence of treatment with inhaled corticosteroids (ICS) on serum NT levels and their influence on the asthmatic state.

METHODS

Eighty-seven volunteers were studied. Thirty-eight were stable allergic asthmatics with constant ICS doses, 29 were asthmatics not receiving anti-asthmatic treatment and 20 were age- and sex-matched healthy controls. Demographic and lung function data were evaluated. NT serum levels were determined by ELISA.

RESULTS

NGF and BDNF levels were significantly increased in untreated asthmatics compared to the control and the treated group, while NT-3 demonstrated significantly higher levels in treated asthmatics compared to healthy controls. After stabilization of untreated subjects with ICS, the NT levels decreased significantly.

CONCLUSIONS

These results suggest that NTs participate in allergic inflammation and asthma. Effective treatment leads to a decrease of circulating neurotrophic factors.

Therapeutic equivalence of the Sofotec Novolizer to established standard devices in COPD and asthma

The Novolizer is a breath-actuated multidose dry powder inhaler that was developed as an alternative to the pressurized metered dose inhalers. The efficacy, safety and tolerability of the Novolizer has been compared with those of established inhalational devices for the delivery of salbutamol (Sultanol) in patients with chronic obstructive pulmonary disease and for the administration of budesonide (Pulmicort Turbuhaler) to patients with asthma. In both studies, improvement in forced expiratory volume in 1 s in patients who were randomly assigned to use the Novolizer was comparable with that in patients who used the established devices. Furthermore, no differences in tolerability or safety between the Novolizer and the control devices were observed. Finally, patient acceptance of the Novolizer was high, with the majority of patients who used it stating that they would use the device again.

Correlation between neutral endopetidase (NEP) 3.4.24.11 in serum and the degree of the bronchial hyperreactivity

Neutral endopeptidase (NEP) is described in airways as the major degrading enzyme of tachykinins such as neurokinin A (NKA) and substance P (SP). Due to its localization and mode of action NEP may play a role in the pathophysiology of bronchial reactivity (BR) especially under the aspect of neurogenic inflammation. Serum NEP concentrations were measured by ELISA to investigate if there is a correlation between serum NEP and the degree of bronchial reactivity expressed by PC20-FEV1 histamine(.). PC20-FEV1 histamine was determined in 31 asthmatic patients [age 31.9+/-1.3 years (mean+/-SEM) FEV1=92.1+/-2.4% (mean+/-SEM) 16 females/15 males]. Prior to the histamine challenge blood samples were obtained and stored at -70 degrees C until determination using ELISA. A significant correlation between serum NEP and the PC20-FEV1 (n=31, r=0.49, P<0.01) was found. The results suggest that serum NEP is modulating neuropeptide-induced effects in the pathophysiology of airway responsiveness.

Substance P induced histamine release from nasal mucosa of subjects with and without allergic rhinitis

OBJECTIVE AND DESIGN

There is evidence that substance P (SP) is involved in events related to allergic and nonallergic rhinitis. Furthermore, some effects of SP seem to be greater in subjects suffering from allergic rhinitis than in nonallergic subjects. To investigate if these effects may be partly mediated by histamine release (HR) we studied the influence of SP on HR from nasal mucosa of subjects with and without allergic rhinitis using an in vitro organ culture system.

SUBJECTS

Nasal mucosa of the inferior turbinate was obtained from ten patients suffering from allergic rhinitis and eighteen non-allergic subjects receiving surgical therapy for nasal obstruction.

METHODS

Tissue samples of nasal mucosa were stimulated with 10(-5) M SP or with 10(-5) M Ca-ionophore A23187 for 120 minutes, and the histamine content was determined in the culture supernatant.

RESULTS

Both SP and Ca-ionophore A23187, caused a significantly higher HR from the samples of the non-allergic group (p < 0.01) compared to baseline controls (spontaneous release). The same effect was seen in the allergic group (p < 0.01 and p = 0.036). Comparing the increase in HR from allergic and non-allergic mucosa, in allergics the HR stimulated by SP was significantly higher (p = 0.031), whereas Ca-ionophore A23187 did not show this effect.

CONCLUSION

These findings suggest a role of SP in inducing release of histamine from human nasal mucosa, thereby influencing physiologic and pathophysiologic nasal conditions, especially in allergic inflammatory processes.

Respimat (a new soft mist inhaler) delivering fenoterol plus ipratropium bromide provides equivalent bronchodilation at half the cumulative dose compared with a conventional metered dose inhaler in asthmatic patients

BACKGROUND

Respimat, a possible alternative to the conventional metered dose inhaler (MDI), is a novel, reusable, propellant-free, multidose soft mist inhaler. Respimat slowly releases a metered dose of active substance as a soft mist with a high proportion of the dose in the fine particle fraction, leading to improved lung deposition following inhalation when compared with the conventional MDI.

OBJECTIVES AND METHODS

The equipotent bronchodilating efficacy and safety of a combination of fenoterol hydrobromide and ipratropium bromide (F/I) in cumulative doses delivered by either Respimat or pressurised MDI was assessed in a randomised, controlled, double-blind (within device) 4-way crossover study. Forty-three patients with stable asthma (mean FEV(1) 62% predicted) responsive to F/I inhaled cumulatively 16 puffs on each of 4 test days (1 + 1 + 2 + 4 + 8 puffs at 50-min intervals) via Respimat delivering 50/20, 25/20 or 25/10 microg F/I per puff or via MDI delivering 50/20 microg F/I per puff.

RESULTS

Cumulative doses of 400/160 and 400/320 microg F/I via Respimat produced bronchodilation (evaluated by average increase in FEV(1) 45-245 min after first inhalation) equivalent to that achieved with a cumulative 800/320 microg F/I via MDI (mean increase in FEV(1) above baseline 0.76, 0.73 and 0.71 litres, respectively). The tolerability of the F/I combination via Respimat was also comparable to that of twice the dose delivered via MDI.

CONCLUSION

Therefore, a fenoterol hydrobromide/ipratropium bromide combination delivered by Respimat is as safe and effective as the MDI at half the cumulative dose, on acute administration to patients with asthma.

Allergen inhalation challenge induces decrease of serum neutral endopeptidase (NEP) in asthmatics

There is accumulating evidence that tachykinins are implicated in inflammation, including asthma. Therefore, we hypothesized that the neutral endopeptidase (NEP), under challenge conditions, could be affected. Serum from 21 asthmatics and six healthy volunteers was sampled before, 30, and 120 min after allergen challenge. NEP-IR was determined using an ELISA and was found in all subjects. Compared to prechallenge, no difference was seen between asthmatics and controls; however, under challenge conditions, NEP-IR in asthmatics was significantly lower (30 min, P = 0.058; 120 min, P = 0.0017, respectively). This finding supports indirectly the hypothesis that tachykinins are released during allergen exposure, and suggests a regulatory role of NEP.

Heparin, derived from the mast cells of human lungs is responsible for the generation of kinins in allergic reactions due to the activation of the contact system

BACKGROUND

In a recent study mast cell heparin proteoglycan (HepPG) of a cell line derived from a mouse mastocytoma was isolated. Glycosaminoglycans proved to be an initiating surface for starting contact activation and could explain kinin generation present in allergic reactions. It is the aim of the present study to prove that HepPG or glycosaminoglycan derived from human mast cells is also capable of acting as a physiologic macromolecule and to induce contact activation.

METHODS

HepPG molecules were isolated by anionic column chromatography. Their ability to accelerate reciprocal activation of factor XII was investigated by spectrophotometry. The anticoagulant effect was demonstrated by an increase in partial thromboplastin time. HPLC was performed to correlate these effects with molecular weight (MW).

RESULTS

The isolated heparin showed high contact-activating and anticoagulant potency. Both actions were suppressed by incubation with heparinase I. The maximum contact activation peak appeared at a lower MW than the anticoagulant effect.

CONCLUSION

These in vitro results explain the results of in vivo allergen challenge studies where a high degree of kinin generation occurs. Heparin derived from human mast cells therefore seems to represent the physiological macromolecule capable of activating the contact system and could be a missing link between cellular and humoral responses in allergic reactions.

Bronchodilation using combined urodilatin - albuterol administration in asthma: a randomized, double-blind, placebo-controlled trial

Urodilatin, the renal form of natriuretic peptide type A, induces bronchodilation, increasing intracellular cyclic guanosine monophosphate (cGMP), whereas the bronchorelaxant effect by b2-agonists is triggered by cyclic adenosine monophosphate (cAMP). The objective of this investigation is to demonstrate the efficacy of urodilatin in inducing bronchodilation, and to show this activity alone or in combination with albuterol. Therefore, a randomized, double-blind, placebo-controlled, dose-finding study with cross-over design was carried out including 12 stable, mild to severe (step 2 to 4, definition by NIH/NHLBI guideline 1997) asthmatics. 96 treatments were thus performed. The intervention was comprised of an intravenous infusion of urodilatin (0, 10, 30, or 60 ng/kg/min) combined with inhaled albuterol (0 or 200 microg). As primary objective, the increase in forced expiratory volume in one second (FEV subset1) was measured. - The trial shows that urodilatin at all applied doses or 200 microg albuterol significantly increases FEV subset1 (p < 0.05). Combination of urodilatin and albuterol treament significantly improves FEV subset1 (p < 0.05) compared to either monotherapy and results in maximum bronchodilation. - From the results, the following conclusions can be drawn. In stable asthmatics, the combined activation of cGMP- and cAMP-mediated pathways results in a significantly improved, maximal bronchodilation in comparison to either type of monotherapy. This shows that urodilatin combined with albuterol improves lung function and ameliorates the therapy in asthmatics.

Influence of ozone and nitrogen dioxide on histamine and interleukin formation in a human nasal mucosa culture system

There is evidence that asthma and other allergic diseases are increasing and air pollution has been considered an important contributing factor to this observation. Using a specially designed organ culture system, we examined the influence of ozone (0.06 to 0. 2 ppm) and nitrogen dioxide (NO2, 200 and 800 micrograms/m3) on nasal mucosa exposed for 24 h. Tissue was obtained from 105 patients undergoing surgical therapy (septoplasty and reduction of the inferior turbinates) for chronic nasal obstruction. The histamine content in the culture medium of ozone- and NO2-exposed samples was significantly elevated compared with the control cultures. This elevation was correlated with the number of degranulated mast cells in the tissue determined by histomorphometry (P < 0.001). Moreover, the cytokines interleukin (IL)-1beta (P < 0.05), IL-6 (P < 0.01), IL-8 (P < 0.001), and tumor necrosis factor-alpha (TNF-alpha, P < 0. 001) were significantly increased (ozone 0.1 ppm). Furthermore, we found significant increases in the release of IL-4, IL-6, IL-8, and TNF-alpha of ozone-exposed (0.1 ppm) samples of atopic versus nonatopic patients and to a lesser extent for histamine following exposure to 0.15 ppm ozone. These results indicate that low ozone concentrations and NO2 lead to an inflammation of human nasal mucosa in vitro and that priming factors such as atopy or preexisting inflammation do increase the sensitivity to ozone and NO2. This organ culture system proved to be a good experimental design for studying pathophysiologic alterations of human nasal mucosa under different experimental conditions (e.g., air pollutants).

Modified T-cell activation pattern during specific immunotherapy (SIT) in cat-allergic patients

OBJECTIVE

The aim of the study was to analyse early effects of specific immunotherapy (SIT) on immune functions in cat-allergic patients.

METHODS

Immunological responses of peripheral blood mononuclear cells from eight cat-allergic patients were analysed before and after SIT in comparison with 11 nonallergic controls. Cells were stimulated in vitro with either bacterial superantigen, mitogen, or cat allergen. Production of IL-12 and TH1/TH2 cytokines was analysed by ELISA and lymphocyte subset distribution was assessed by flow-cytometry.

RESULTS

We found a significantly reduced secretion of IL-12 (P < 0.05) from cells of allergic individuals compared with the controls. This finding was associated with significantly lower IFN-gamma production after stimulation with allergen (P < 0.05) that did not increase during SIT. However, no significant differences were seen after stimulation with mitogen indicating an allergen specific IFN-gamma secretion response in allergic individuals. Prior to SIT IL-5 production was significantly higher in cells of allergic donors stimulated with allergen < 0.005 or mitogen (< 0.05). After reaching the maintenance dose for SIT, allergen-induced IL-5 production returned to normal levels, whereas it remained elevated after stimulation with mitogen. These changes were associated with a reduced frequency of CD45 RO T cells following SIT.

CONCLUSION

These results suggest that SIT exerts early effects on allergen-specific T-cell responses with selective inhibition of the up-regulated TH2 immune response.

Serum eosinophil cationic protein (ECP) as a mediator of inflammation in acute asthma, during resolution and during the monitoring of stable asthmatic patients treated with inhaled steroids according to a dose reduction schedule

OBJECTIVE AND DESIGN

The main objective was to establish the level of serum ECP in a group of adult asthmatic patients with acute exacerbation and the following resolution and in another group of adult, stable asthmatic patients during reduction of inhaled steroids.

SUBJECTS AND TREATMENT

Acute group: Twenty-one asthmatic patients admitted to the asthma clinic with acute deterioration of their asthma were set on oral steroids which were reduced to 0 within one week. Reduction group: Forty-four stable asthmatic patients on maintenance inhaled steroids were included and, on the basis of their peak expiratory flow (PEF) values, adjustments in the doses of steroids were made.

CONTROL GROUP

Twenty stable asthmatics on a constant dose of inhaled steroids were enrolled as controls.

METHODS

All patients registered daily PEF measurements and spirometry was performed at each visit. Blood samples were drawn and analysed for eosinophil cationic protein (ECP), myeloperoxidase (MPO), eosinophils and neutrophils.

RESULTS

ECP was low and within the normal range for all three groups at study entry. (Acute group = 8.4 microg/l, reduction group = 3.7 microg/l and control group = 4.6 microg/l). Nevertheless, the value in the acute group was significantly higher than in the control group (p=0.005). The levels in the acute group decreased significantly (p=0.004) after one week on oral steroids. No significant changes in ECP were observed in the reduction group or in the control group during the follow-up period. The lung function was low in the acute group at inclusion, forced expiratory volume in one second (FEV1)=47.1% of predicted, and increased significantly during the treatment period (p = 0.006). The patients in the reduction- and control group showed small variations in lung function during the whole study, FEV1 >70% and PEF > 80% of predicted, respectively. No correlation between atopy and ECP was found in the patients irrespective of the stage of disease.

CONCLUSIONS

This study suggests that the resolution of acute asthma exacerbations during treatment could be followed using ECP determinations. In stable asthmatics on inhaled steroids and with normal ECP levels, a dose reduction could be indicated. A longer period after tapering off steroids is proposed to confirm the benefit of ECP measurements for controlling asthma.