Molecular aspects of rheumatoid arthritis: chemokines in the joints of patients

Rheumatoid arthritis (RA) is a chronic symmetric polyarticular joint disease that primarily affects the small joints of the hands and feet. The inflammatory process is characterized by infiltration of inflammatory cells into the joints, leading to proliferation of synoviocytes and destruction of cartilage and bone. In RA synovial tissue, the infiltrating cells such as macrophages, T cells, B cells and dendritic cells play important role in the pathogenesis of RA. Migration of leukocytes into the synovium is a regulated multi-step process, involving interactions between leukocytes and endothelial cells, cellular adhesion molecules, as well as chemokines and chemokine receptors. Chemokines are small, chemoattractant cytokines which play key roles in the accumulation of inflammatory cells at the site of inflammation. It is known that synovial tissue and synovial fluid from RA patients contain increased concentrations of several chemokines, such as monocyte chemoattractant protein-4 (MCP-4)/CCL13, pulmonary and activation-regulated chemokine (PARC)/CCL18, monokine induced by interferon-gamma (Mig)/CXCL9, stromal cell-derived factor 1 (SDF-1)/CXCL12, monocyte chemotactic protein 1 (MCP-1)/CCL2, macrophage inflammatory protein 1alpha (MIP-1alpha)/CCL3, and Fractalkine/CXC3CL1. Therefore, chemokines and chemokine-receptors are considered to be important molecules in RA pathology.     

Skewed Production of IL-6 and TGFβ by Cultured Salivary Gland Epithelial Cells from Patients with Sj?gren's Syndrome

Objective

To determine the cytokine production profile of cultured salivary gland epithelial (SGE) cells obtained from patients with Sjögren''s syndrome (SS).

Methods

SGE cells obtained from 9 SS patients and 6 normal controls were cultured in the presence of exogenous IFNγ. Cell proliferation and apoptosis in response to IFNγ were determined by WST1 assay and by FACS analysis. The concentrations of IL-6 and TGFβ secreted into culture supernatants were analyzed by ELISA.

Results

IFNγ did not significantly affect the proliferation or apoptosis of SGE cells. However, IL-6 concentrations were higher, and TGFβ concentrations were lower, in culture supernatants of SGE cells from SS patients than from normal controls.

Conclusion

Cytokine production by SGE cells from SS patients showed a skewed balance compared with normal controls, with increased IL-6 and decreased TGFβ secretion. This imbalance may be critical in the regulation of Treg/Th17 cells and may foster a pathogenic milieu that may be causative and predictive in SS.     

Two new species of the genus Micromonospora: Micromonospora chokoriensis sp. nov. and Micromonospora coxensis sp. nov., isolated from sandy soil

Two actinomycete strains, 2-19(6)(T) and 2-30-b(28)(T), which produced single, non-motile noduler to warty spore surfaces, were isolated from sandy soil in Chokoria, Cox's Bazar, Bangladesh. A polyphasic study was carried out to establish the taxonomic position of these strains. Morphological and chemotaxonomic characteristics of these strains coincided with those of the genus Micromonospora. Phylogenetic analysis using 16S rDNA sequences indicated that these strains should be classified in the genus Micromonospora. The 16S rDNA sequence of strain 2-19(6)(T )showed closest similarity to the type strains of M. mirobrigensis (98.9%) and M. carbonacea (98.8%), and the strain 2-30-b(28)(T) to the type strains of M. purpureochromogenes (99.4%), M. halophytica (99.3%) and M. aurantiaca (99.2%). Furthermore, a combination of DNA-DNA hybridization results and some differential physiological and biochemical properties indicated that these strains were distinguished from the phylogenetically closest relatives. These strains therefore represent two novel species, for which the name Micromonospora chokoriensis sp. nov. and Micromonospora coxensis sp. nov. are proposed. The type strains are 2-19(6)(T) (=JCM 13247(T) =MTCC 8535(T)) and 2-30-b(28)(T) (=JCM 13248(T)=MTCC 8093(T)).     

Toward molecular trait‐based ecology through integration of biogeochemical,geographical and metagenomic data

Using metagenomic ‘parts lists’ to infer global patterns on microbial ecology remains a significant challenge. To deduce important ecological indicators such as environmental adaptation, molecular trait dispersal, diversity variation and primary production from the gene pool of an ecosystem, we integrated 25 ocean metagenomes with geographical, meteorological and geophysicochemical data. We find that climatic factors (temperature, sunlight) are the major determinants of the biomolecular repertoire of each sample and the main limiting factor on functional trait dispersal (absence of biogeographic provincialism). Molecular functional richness and diversity show a distinct latitudinal gradient peaking at 20°N and correlate with primary production. The latter can also be predicted from the molecular functional composition of an environmental sample. Together, our results show that the functional community composition derived from metagenomes is an important quantitative readout for molecular trait‐based biogeography and ecology.     

Multiplex analysis of sphingolipids using amine-reactive tags (iTRAQ)

Ceramides play a crucial role in divergent signaling events, including differentiation, senescence, proliferation, and apoptosis. Ceramides are a minor lipid component in terms of content; thus, highly sensitive detection is required for accurate quantification. The recently developed isobaric tags for relative and absolute quantitation (iTRAQ) method enables a precise comparison of both protein and aminophospholipids. However, iTRAQ tagging had not been applied to the determination of sphingolipids. Here we report a method for the simultaneous measurement of multiple ceramide and monohexosylceramide samples using iTRAQ tags. Samples were hydrolyzed with sphingolipid ceramide N-deacylase (SCDase) to expose the free amino group of the sphingolipids, to which the N-hydroxysuccinimide group of iTRAQ reagent was conjugated. The reaction was performed in the presence of a cleavable detergent, 3-[3-(1,1-bisalkyloxyethyl)pyridine-1-yl]propane-1-sulfonate (PPS) to both improve the hydrolysis and ensure the accuracy of the mass spectrometry analysis performed after iTRAQ labeling. This method was successfully applied to the profiling of ceramides and monohexosylceramides in sphingomyelinase-treated Madin Darby canine kidney (MDCK) cells and apoptotic Jurkat cells.     

Existence of S-Glycoprotein-Like Proteins in Anthers of Self-Incompatible Species of Brassica

Experimental evidence is presented that there exists an antherprotein that is reactive with a polyclonal antiserum raisedagainst the stigma S-glycoprotein of the S⁸-homozygote of Brassicacampestris. The antiserum did not react with extracts of seeds,ovaries or leaves. Since this antiserum did not react with thepolysaccharide residues similar to those in S-glycoprotein,it was considered capable of identifying S-glycoprotein-likeproteins in anthers (SA-protein: S-glycopro-tein-like antherprotein). The SA-protein generated a single distinct band ata pI of about 5.0 on blots of gels after isoelectric focusingand three spots at 29 kDa and 83 kDa on blots of two-dimensionalgels, which were different from those of stigma S-glycoprotein.The SA-protein did not contain polysaccharide residue that reactedwith Con A. No allelic differences in pI were found for theSA-protein within a given species, while such differences arecommon in stigma S-glycoprotein. The SA-protein appeared inanthers at the uninucleate microspore stage which is much earlierthan the stage at which the stigma S-xglycoprotein appears.It is present in anther walls rather than in the pollen of matureanthers. The SA-protein is considered to play an important rolein sporophytic control of self-incompatibility. (Received April 2, 1991; Accepted July 24, 1991)     

Inhibition of FGF10-ERK signal activation suppresses intraductal papillary neoplasm of the bile duct and its associated carcinomas

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Meta-analysis of variation suggests that embracing variability improves both replicability and generalizability in preclinical research

The replicability of research results has been a cause of increasing concern to the scientific community. The long-held belief that experimental standardization begets replicability has also been recently challenged, with the observation that the reduction of variability within studies can lead to idiosyncratic, lab-specific results that cannot be replicated. An alternative approach is to, instead, deliberately introduce heterogeneity, known as “heterogenization” of experimental design. Here, we explore a novel perspective in the heterogenization program in a meta-analysis of variability in observed phenotypic outcomes in both control and experimental animal models of ischemic stroke. First, by quantifying interindividual variability across control groups, we illustrate that the amount of heterogeneity in disease state (infarct volume) differs according to methodological approach, for example, in disease induction methods and disease models. We argue that such methods may improve replicability by creating diverse and representative distribution of baseline disease state in the reference group, against which treatment efficacy is assessed. Second, we illustrate how meta-analysis can be used to simultaneously assess efficacy and stability (i.e., mean effect and among-individual variability). We identify treatments that have efficacy and are generalizable to the population level (i.e., low interindividual variability), as well as those where there is high interindividual variability in response; for these, latter treatments translation to a clinical setting may require nuance. We argue that by embracing rather than seeking to minimize variability in phenotypic outcomes, we can motivate the shift toward heterogenization and improve both the replicability and generalizability of preclinical research.

A meta-analysis study of the variability in phenotypic outcomes in both control and experimental animal models of ischaemic stroke provides novel perspectives in which heterogeneity can be embraced to improve the reproducibility and translation of preclinical studies.     

Molecular phylogeny and host use evolution of the genus Exorista Meigen (Diptera: Tachinidae)

Members of the genus Exorista are parasitoids of a diverse array of insect hosts in the orders, Lepidoptera, Hymenoptera, Mantodea and Orthoptera. Phylogenetic relationships among subgenera and species of Exorista were inferred using four nuclear (Tpi, white, 18S and 28S) and four mitochondrial DNA (16S, 12S, ND5 and CO1) genes in maximum parsimony (MP), maximum likelihood (ML) and Bayesian Markov chain Monte Carlo (MCMC) analyses. Separate trees based on different sets of genes (mt DNA, nuclear, ribosomal, etc.) were compared and found to be nearly concordant. According to the molecular tree generated from the concatenated sequence data, the genus Exorista is paraphyletic. The phylogenetic analyses indicate the existence of two major clades of Exorista, including two genera Parasetigena and Phorocera. Morphological traits supporting clades indicated by molecular analyses within this genus are evaluated. Evolutionary patterns of the host use and host shifts are examined by optimizing host information using maximum likelihood on the molecular phylogeny. The ancestral host group of the tribe Exoristini (excluding Ctenophorinia and Phorinia) appears to be the order Lepidoptera, although hosts of some species are unknown. A major host shift to the Hymenoptera occurred in the clade of subgenus Adenia, and the ancestral state of subgenus Spixomyia is equivocal because there is little information available on the hosts in members of a subclade of this group (subclade A: Exorista hyalipennis group).