Effect of JAK Inhibition on the Induction of Proinflammatory HLA-DR+CD90+ Rheumatoid Arthritis Synovial Fibroblasts by Interferon-γ

OBJECTIVE

Findings from recent transcriptome analyses of the synovium of patients with rheumatoid arthritis (RA) have revealed that 15-fold expanded HLA-DR+CD90+ synovial fibroblasts potentially act as key mediators of inflammation. The reasons for the expansion of HLA-DR+CD90+ synovial fibroblasts are unclear, but genetic signatures indicate that interferon-γ (IFNγ) plays a central role in the generation of this fibroblast subset. The present study was undertaken to investigate the generation, function and therapeutically intended blockage of HLA-DR+CD90+ synovial fibroblasts.

METHODS

We combined functional assays using primary human materials and focused bioinformatic analyses of mass cytometry and transcriptomics patient data sets.

RESULTS

We detected enriched and activated Fcγ receptor type IIIa-positive (CD16+) NK cells in the synovial tissue from patients with active RA. Soluble immune complexes were recognized by CD16 in a newly described reporter cell model, a mechanism that could be contributing to the activation of natural killer (NK) cells in RA. In vitro, NK cell-derived IFNγ induced HLA-DR on CD90+ synovial fibroblasts, leading to an inflammatory, cytokine-secreting HLA-DR+CD90+ phenotype. HLA-DR+CD90+ synovial fibroblasts consecutively activated CD4+ T cells upon receptor crosslinking via superantigens. HLA-DR+CD90+ synovial fibroblasts also activated CD4+ T cells in the absence of superantigens, an effect that was initiated by NK cell-derived IFNγ and that was 4 times stronger in patients with RA compared to patients with osteoarthritis. Finally, JAK inhibition in synovial fibroblasts prevented HLA-DR induction and blocked proinflammatory signals to T cells.

CONCLUSION

The HLA-DR+CD90+ phenotype represents an activation state of synovial fibroblasts during the process of inflammation in RA that can be induced by IFNγ, likely generated from infiltrating leukocytes such as activated NK cells. The induction of these proinflammatory, interleukin-6-producing, and likely antigen-presenting synovial fibroblasts can be targeted by JAK inhibition.

Complementary medicine in Germany: a multi-centre cross-sectional survey on the usage by and the needs of patients hospitalized in university medical centers

BACKGROUND

The results of recent surveys indicate that more than 50% of the German population has experience with complementary and alternative medicine (CAM) or uses CAM regularly. This study investigated the CAM usage and CAM-related needs of hospitalized patients at university medical centres in the state of Baden-Württemberg, Germany.

METHODS

A multi-centre, paper-based, pseudonymous survey was carried out by the members of the Academic Centre for Complementary and Integrative Medicine. Patients of all ages, regardless of sex, diagnosis and treatment, who were hospitalized in the Department of Cardiology, Gastroenterology, Oncology, Gynaecology or Surgery at the university medical centres in Freiburg, Heidelberg, Tübingen and Ulm were eligible for inclusion.

RESULTS

Of the 1275 eligible patients, 67% (n = 854) consented to participate in the survey. Forty-eight percent of the study participants stated that they were currently using CAM. The most frequently used therapies were exercise (63%), herbal medicine (54%) and dietary supplements (53%). Only 16% of the patients discussed CAM usage with their attending physician. Half of the patients (48%) were interested in CAM consultations. More than 80% of the patients desired reliable CAM information and stated that physicians should be better informed about CAM.

CONCLUSIONS

The frequency of CAM usage and the need for CAM counselling among hospitalized patients at university medical centres in Baden-Württemberg are high. To better meet patients' needs, CAM research and physician education should be intensified.

TRIAL REGISTRATION

German Clinical Trial register ( DRKS00015445 ).

Role of membrane curvature in mechanoelectrical transduction: Ion carriers nonactin and valinomycin sense changes in integral bending energy

We describe the phenomenon of mechanoelectrical transduction in macroscopic lipid bilayer membranes modified by two cation-selective ionophores, valinomycin and nonactin. We found that bulging these membranes, while maintaining the membrane tension constant, produced a marked supralinear increase in specific carrier-mediated conductance. Analyses of the mechanisms involved in mechanoelectrical transduction induced by the imposition of a hydrostatic pressure gradient or by an amphipathic compound chlorpromazine reveal similar changes in the charge carrier motility and carrier reaction rates at the interface(s). Furthermore, the relative change in membrane conductance was independent of membrane diameter, but was directly proportional to the square of membrane curvature, thus relating the observed phenomena to the bilayer bending energy. Extrapolated to biological membranes, these findings indicate that ion transport in cells can be influenced simply by changing shape of the membrane, without a change in membrane tension.

Quinolones for uncomplicated acute cystitis in women

BACKGROUND

Uncomplicated acute cystitis is one of the most common bacterial infections in adults. The percentage of women who have at least one episode of acute cystitis is estimated to be between 40% to 50%. Quinolones are recommended for acute cystitis in regions where the level of resistance to other antimicrobials namely co-trimoxazole is high. However the efficacy, safety and tolerance of quinolones needs investigation.

OBJECTIVES

To compare the efficacy, safety and tolerance of different quinolones in women with uncomplicated acute cystitis.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL, in The Cochrane Library Issue 3, 2003), MEDLINE (1966 - September 2003), EMBASE (1988 - September 2003), reference lists of articles and abstracts from conference proceedings without language restriction. Reference lists of urology, infectious diseases and nephrology textbooks, review articles and relevant studies.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials comparing two or more different quinolones in women (>/= 16 years) with uncomplicated acute cystitis were selected.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed trial quality and extracted data. Statistical analyses were performed using the random effects model and the results expressed as relative risk (RR) for dichotomous outcomes with 95% confidence intervals (CI).

MAIN RESULTS

We identified 11 studies enrolling 7535 women. There were no significant differences in clinical or microbiological efficacy between quinolones. Photosensitivity reactions were more frequently observed for sparfloxacin when compared to ofloxacin. Any adverse event, adverse events causing withdrawal, skin adverse events, photosensitivity reactions were more common for lomefloxacin when compared to norfloxacin. Any adverse event, adverse drug reactions, CNS adverse events were more common for ofloxacin when compared to ciprofloxacin. CNS adverse events and insomnia were more often reported for rufloxacin when compared to pefloxacin. Adverse drug reactions occurred frequently for ofloxacin than levofloxacin. Insomnia was reported more frequently for enoxacin than ciprofloxacin.

AUTHORS' CONCLUSIONS

We found no significant differences in clinical or microbiological efficacy between quinolones but some differences in occurrence and spectrum of quinolone safety.

A genetically engineered fusion protein with horseradish peroxidase as a marker enzyme for use in competitive immunoassays

Horseradish peroxidase is one of the most widely used marker enzymes in immunoassays. Several disadvantages are encountered upon chemical conjugation of peroxidase with antibodies or antigens, as are low reproducibility and undefined stoichiometry. We here describe for the first time the production of a recombinant fusion of a protein analyte with horseradish peroxidase in Escherichia coli, employing refolding of inclusion bodies and reconstitution with heme. The genetic fusion approach enables preparation of conjugates with 1:1 stoichiometry and defined structure. As a protein analyte, the human heart fatty acid binding protein (H-FABP) was chosen, which is a new and sensitive marker for acute myocardial infarction. The recombinant conjugate was fully active [650 U/mg with 2,2-azino-bis(3-ethyl-thiazoline-6-sulfonate) as substrate] and obtained in a yield of 12 mg/L of E. coli culture, which is better than that for recombinant peroxidase alone. The competitive immunoassay that was developed with the recombinant conjugate requires fewer incubation steps than the traditional sandwich ELISA format. It permitted the detection of H-FABP directly in plasma in the range of 10-1500 ng/mL which is the relevant range for clinical decision-making.

New restriction endonucleases from thermophilic soil bacteria

Using the most effective rapid method for the detection of restriction endonucleases (ENases) in microorganisms, 32 thermophilic producers have been isolated. All strains belong to the genus Bacillus. Thermostable isoschizomers of ENases, such as AvaI, BbvI, BbvII, BclI, BsaBI, BsiYI, BsrI, BstEII, BstNI, Cfr10I, ClaI, FspI, HaeIII, HpaII, Ksp632I and SfeI, were isolated.