Comparison of paediatric and adult classification criteria in juvenile idiopathic arthritis during the transition from paediatric to adult care.

OBJECTIVES: To determine the characteristics of juvenile idiopathic arthritis (JIA) patients seen during the transition period in order to compare paediatric classification criteria with those for adults. METHODS: Patients with JIA according to the ILAR classification and who had a consultation at transition between 2010 and 2017 were included in a retrospective bi-centre (Lyon, Lausanne) study. JIA classification criteria were compared to ACR/EULAR 2010 criteria for rheumatoid arthritis (RA), Yamaguchi criteria for adult-onset Still's disease (AOSD), ASAS criteria for spondyloarthritis and CASPAR criteria for psoriatic arthritis. RESULTS: One hundred and thirty patients were included: 13.9% with systemic JIA, 22.3% with polyarticular JIA, 22.3% with oligoarticular JIA, 34.6% with enthesitis-related arthritis (ERA) and 6.9% with psoriatic arthritis; 13.1% had suffered from uveitis; 14.5% of patients had erosions or carpitis, mainly those with psoriatic arthritis, polyarticular or systemic JIA; 37.5% of patients with ERA displayed radiological sacroiliitis. When comparing paediatric JIA criteria with adult classifications, we found that: 66.6% of patients with systemic JIA fulfilled the criteria for AOSD, 87.5% of rheumatoid factor-positive polyarticular JIA and 9.5% of rheumatoid factor-negative polyarticular JIA met the criteria for RA, and 34.5% of oligoarticular JIA fulfilled the criteria for spondyloarthritis. Finally, 77.7% of patients with ERA met the criteria for spondyloarthritis, and 100% of patients with psoriatic arthritis JIA met the criteria for psoriatic arthritis. CONCLUSION: Oligoarticular JIA and rheumatoid factor-negative polyarticular JIA seem to be paediatric entities, whereas the other types of JIA tended to meet the respective adult classification criteria.

Building a transitional care checklist in rheumatology: A Delphi-like survey.

OBJECTIVES: To design a transitional care checklist to be used by and facilitate the work of health professionals in providing transitional care for children with a chronic rheumatologic disease and their families. METHODS: A Delphi-like study among an international expert panel was carried out in four steps: (1) a working group of 6 specialists established a draft; (2) a web-survey among a panel of international experts evaluated it; (3) a 2-day consensus conference with an expert panel discussed items not reaching agreement; (4) a web-survey among the panel of international experts with the list of reformulated items. RESULTS: The first draft of the checklist included 38 items in 3 phases of transition and 5 age groups. Thirty-three international experts evaluated the checklist reaching≥80% agreement for 26 items and ≤80% for 12. The consensus conference of 12 experts discussed and redefined the 12 items. Twenty-five international experts filled out the web-survey and all items reached a minimum of 80% agreement except one. The final checklist was reached. CONCLUSIONS: This Delphi-like study defined what themes should be included and at what age they need to be addressed with patients with a chronic rheumatology disease and their families during transition. This checklist reached a strong international and interdisciplinary consensus while examining transition in a broad way. It should now be spread widely to health professionals to be used by all those who care for adolescents aged≥12 years at times of transition. It could be transposed to most chronic conditions. Recommendations for further research are given.

Identification of the cysteine protease Amb a 11 as a novel major allergen from short ragweed.

BACKGROUND: Allergy to pollen from short ragweed (Ambrosia artemisiifolia) is a serious and expanding health problem in the United States and in Europe. OBJECTIVE: We sought to investigate the presence of undescribed allergens in ragweed pollen. METHODS: Ragweed pollen proteins were submitted to high-resolution gel electrophoresis and tested for IgE reactivity by using sera from 92 American or European donors with ragweed allergy. Pollen transcriptome sequencing, mass spectrometry (MS), and recombinant DNA technologies were applied to characterize new IgE-binding proteins. RESULTS: High-resolution IgE immunoblotting experiments revealed that 50 (54%) of 92 patients with ragweed allergy were sensitized to a 37-kDa allergen distinct from Amb a 1. The full-length cDNA sequence for this molecule was obtained by means of PCR cloning after MS sequencing of the protein combined with ragweed pollen RNA sequencing. The purified allergen, termed Amb a 11, was fully characterized by MS and confirmed to react with IgEs from 66% of patients. This molecule is a 262-amino-acid thiol protease of the papain family expressed as a combination of isoforms and glycoforms after proteolytic removal of N- and C-terminal propeptides from a proform. Three-dimensional modeling revealed a high structural homology with known cysteine proteases, including the mite Der p 1 allergen. The protease activity of Amb a 11, as well as its capacity to activate basophils from patients with ragweed allergy, were confirmed. The production of a nonglycosylated recombinant form of Amb a 11 in Escherichia coli established that glycosylation is not required for IgE binding. CONCLUSION: We identified the cysteine protease Amb a 11 as a new major allergen from ragweed pollen. Given the similar physicochemical properties shared by the 2 major allergens, we hypothesize that part of the allergenic activity previously ascribed to Amb a 1 is rather borne by Amb a 11.

Complementary mass spectrometric approaches and scanning electron microscopy to study the structural stability of polyurethane tunneled dialysis catheters after exposure to ethanol solutions.

RATIONALE: Ethanol lock is an emerging therapeutic option for preventing and/or controlling catheter-associated infection. A previous study of silicone catheters showed they underwent no polymer degradation when kept in 60% ethanol for 15 days at 37 °C. The stability of the more widely used polyurethane catheters was studied here in the same way. METHODS: A qualitative and quantitative study of the stability of Carbothane® catheters was performed following their immersion at 37 °C in different solvents (0.9% sodium chloride as control medium and 40%, 60%, 95% ethanol solutions) for different periods of time (from 5 min to 15 days) using scanning electron microscopy and complementary mass spectrometry techniques. RESULTS: Electron ionization analysis of the 95% ethanol storage solutions revealed the release of about 45 products (8 of which were major) subdivided into two groups according to their fragmentation patterns. Combining all the mass spectrometric data made it possible to propose structures. Group I (major) originated from the polycarbonate diol component (soft segment) and group II (minor) from the dicyclohexylmethane-4,4'-diisocyanate component (rigid segment). Semi-quantitative gas chromatography/mass spectrometry (GC/MS) analysis showed that no significantly higher release was observed after immersion for 30 min at 37 °C in 40% ethanol (mean ratio = 0.677 ± 0.068) than after immersion in reference 0.9% sodium chloride solution for 15 days (0.837 ± 0.127). CONCLUSIONS: A 30 min-40% (v/v) ethanol solution can be considered as safe for preventing the infectious complications of Carbothane® dialysis catheters, and a 30 min-60% (v/v) ethanol treatment can be occasionally used to eradicate established biofilm.

Spacer optimization of new conjugates for a melanoma-selective delivery approach.

In the search for more selective anticancer drugs, we designed and synthesized seven conjugates varying the structure of the linker connecting the 5-iodo-2'-deoxyuridine (IUdR) to the ICF 01012 melanoma-carrier for potential intratumoural specific drug release. Chemical and in vitro metabolic stability evaluations showed that, except for the ester conjugate (1), the ketal (2b), acetal (2a), carbonate (4) and carbamate (3) conjugates were compatible with our approach. The acetal (2a) and its PEGylated derivative (2c) were of particular interest for further in vivo development owing to their respective pH-dependent stability and limited metabolic degradation in order to exploit the acidic subcellular environment of malignant melanocytes to trigger the release of therapeutics upon internalization in cells.

Incidence and risk factors of Legionella pneumophila pneumonia during anti-tumor necrosis factor therapy: a prospective French study.

OBJECTIVE: Our objective was to describe the incidence and risk factors of legionellosis associated with tumor necrosis factor (TNF)-α antagonist use. METHODS: From February 1, 2004, to January 31, 2007, we prospectively collected all cases of legionellosis among French patients receiving TNF-α antagonists in the Research Axed on Tolerance of Biotherapies (RATIO) national registry. We conducted an incidence study with the French population as a reference and a case-control analysis with four control subjects receiving TNF-α antagonists per case of legionellosis. RESULTS: Twenty-seven cases of legionellosis were reported. The overall annual incidence rate of legionellosis for patients receiving TNF-α antagonists, adjusted for age and sex, was 46.7 (95% CI, 0.0-125.7) per 100,000 patient-years. The overall standardized incidence ratio (SIR) was 13.1 (95% CI, 9.0-19.1; P < .0001) and was higher for patients receiving infliximab (SIR, 15.3 [95% CI, 8.5-27.6; P < .0001]) or adalimumab (SIR, 37.7 [95% CI, 21.9-64.9; P < .0001]) than etanercept (SIR, 3.0 [95% CI, 1.00-9.2; P = .06]). In the case-control analysis, exposure to adalimumab (OR, 8.7 [95% CI, 2.1-35.1]) or infliximab (OR, 9.2 [95% CI, 1.9-45.4]) vs etanercept was an independent risk factor for legionellosis. CONCLUSIONS: The incidence rate of legionellosis for patients receiving TNF-α antagonists is high, and the risk is higher for patients receiving anti-TNF-α monoclonal antibodies than soluble TNF-receptor therapy. In case of pneumonia occurring during TNF-α antagonist therapy, specific urine antigen detection should be performed and antibiotic therapy should cover legionellosis. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT00224562; URL: www.clinicaltrials.gov.

Mass spectrometric investigation of molecular variability of grass pollen group 1 allergens.

Natural grass pollen allergens exhibit a wide variety of isoforms. Precise characterization of such microheterogeneity is essential to improve diagnosis and design appropriate immunotherapies. Moreover, standardization of allergen vaccine production is a prerequisite for product safety and efficiency. Both qualitative and quantitative analytical methods are thus required to monitor and control the huge natural variability of pollens, as well as final product quality. A proteomic approach has been set up to investigate in depth the structural variability of five group 1 allergens originating from distinct grass species (Ant o 1, Dac g 1, Lol p 1, Phl p 1, and Poa p 1). Whereas group 1 is the most conserved grass pollen allergen, great variations were shown between the various isoforms found in these five species using mass spectrometry, with many amino acid exchanges, as well as variations in proline hydroxylation level and in main N-glycan motifs. The presence of O-linked pentose residues was also demonstrated, with up to three consecutive units on the first hydroxyproline of Ant o 1. In addition, species-specific peptides were identified that might be used for product authentication or individual allergen quantification. Lastly, natural or process-induced modifications (deamidation, oxidation, glycation) were evidenced, which might constitute useful indicators of product degradation.

High throughput screening of mixed-mode sorbents and optimisation using pre-packed lab-scale columns for the purification of the recombinant allergen rBet v 1a.

Mixed-mode chromatography was investigated for the purification of the recombinant allergen rBet v 1a expressed in Escherichia coli (E. coli) and used as an active principle for specific immunotherapy (SIT) treatment against birch pollen allergy. The screening of micro-volumes of three mixed-mode sorbents established that rBet v 1a could be captured without any pre-treatment of the crude feedstock on HEA or PPA HyperCel sorbents equilibrated in "physiological-like" conditions. On a mini-column pre-packed with PPA HyperCel sorbent, rBet v 1a was recovered at pH 4, partially separated from a major methionine Bet v 1 contaminant and purified approximately 9-fold in a single step (85% purity).

Production and proteomic characterization of pharmaceutical-grade Dermatophagoides pteronyssinus and Dermatophagoides farinae extracts for allergy vaccines.

BACKGROUND: House dust mites (HDM) such as Dermatophagoides pteronyssinus and Dermatophagoides farinae represent a major cause of type 1 allergies worldwide. Hence large quantities of well-characterized HDM extracts are needed to prepare pharmaceutical-grade allergy vaccines. To this aim, the present study was undertaken to define optimal conditions for large-scale cultures. METHODS: D. pteronyssinus and D. farinae were grown on different media combining various proportions of wheat germ, yeast and synthetic amino acids (the latter resembling the composition of the human stratum corneum). Extracts thus obtained were analyzed for their total allergenic activity, as well as major allergen and protein contents, using immunosorbent assays, HPLC, immunoblotting, two-dimensional electrophoresis and peptide mass fingerprinting. RESULTS: An optimal culture medium (Stalmite APF) based on wheat germ, yeast and amino acids in defined proportion (42, 42 and 15% w/w, respectively) was selected to grow various HDM species with high yields. A detailed proteomic analysis revealed that D. pteronyssinus extracts generated under such conditions did not contain allergens originating from culture medium components and that major prevalent HDM allergens (i.e. groups 1, 2, 7, 10, 13 and 20) are found among the most abundant proteins in the D. pteronyssinus extract. Semiquantitative dot-blot assays confirmed the presence of Der p 3-10 as well as Der p 13 and 14 allergens within the extracts. CONCLUSIONS: We developed a well-defined medium allowing to grow various HDM species at an industrial scale in a highly reproducible manner. Extracts from mites produced under such pharmaceutical conditions contain all the relevant allergens for desensitization purposes and in vivo diagnosis.

Characterization of wild-type recombinant Bet v 1a as a candidate vaccine against birch pollen allergy.

BACKGROUND: We describe the production in Escherichia coli as a recombinant protein of clinical grade wild-type Bet v 1a (rBet v 1a), to be used as a candidate vaccine against birch pollen allergy. METHODS: This recombinant protein was purified by hydrophobic interaction and ion exchange chromatography and characterized by SDS-PAGE, immunoprint and circular dichroism in parallel with natural Bet v 1 (nBet v 1) purified from a birch pollen extract. We also compared rBet v 1 and nBet v 1 for their capacity to induce histamine release from basophils and to stimulate T lymphocyte proliferation. RESULTS: rBet v 1a appears in SDS-PAGE as an 18-kDa monomeric protein, whereas purified nBet v 1 comprises a mixture of isoforms (resolving as three distinct bands and six spots after 1-dimensional and 2-dimensional electrophoresis, respectively). Both recombinant and natural purified Bet v 1 molecules are recognized by IgE from birch pollen-allergic patients as well as anti-Bet v 1 murine monoclonal antibodies, suggesting that the recombinant protein is correctly folded in a native configuration. Circular dichroism analysis confirmed that the two Bet v 1 molecules exhibit similar 3-dimensional structures, even if rBet v 1a appears more compact and stable in thermodenaturation/renaturation experiments. Both rBet v 1 and nBet v 1 induce the degranulation of sensitized basophils and proliferation of Bet v 1-specific T lymphocytes in a similar manner. CONCLUSIONS: On the basis of these structural and biological properties, rBet v 1a is a valid candidate vaccine against birch pollen allergy, currently evaluated in humans.