Polymorphisms of the ITGAM Gene Confer Higher Risk of Discoid Cutaneous than of Systemic Lupus Erythematosus

Background Lupus erythematosus (LE) is a heterogeneous disease ranging from mainly skin-restricted manifestations (discoid LE [DLE] and subacute cutaneous LE) to a progressive multisystem disease (systemic LE [SLE]). Genetic association studies have recently identified several strong susceptibility genes for SLE, including integrin alpha M (ITGAM), also known as CD11b, whereas the genetic background of DLE is less clear. Principal findings To specifically investigate whether ITGAM is a susceptibility gene not only for SLE, but also for cutaneous DLE, we genotyped 177 patients with DLE, 85 patients with sporadic SLE, 190 index cases from SLE families and 395 population control individuals from Finland for nine genetic markers at the ITGAM locus. SLE patients were further subdivided by the presence or absence of discoid rash and renal involvement. In addition, 235 Finnish and Swedish patients positive for Ro/SSA-autoantibodies were included in a subphenotype analysis. Analysis of the ITGAM coding variant rs1143679 showed highly significant association to DLE in patients without signs of systemic disease (P-value = 4.73x10-11, OR = 3.20, 95% CI = 2.23-4.57). Significant association was also detected to SLE patients (P-value = 8.29x10-6, OR = 2.14, 95% CI = 1.52-3.00), and even stronger association was found when stratifying SLE patients by presence of discoid rash (P-value = 3.59x10-8, OR = 3.76, 95% CI = 2.29-6.18). Significance We propose ITGAM as a novel susceptibility gene for cutaneous DLE. The risk effect is independent of systemic involvement and has an even stronger genetic influence on the risk of DLE than of SLE.Peer reviewe

Regional and supra-regional coherence in limnological variables

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Characterization of a new chronic lymphocytic leukemia cell line for mechanistic in vitro and in vivo studies relevant to disease.

Studies of chronic lymphocytic leukemia (CLL) have yielded substantial progress, however a lack of immortalized cell lines representative of the primary disease has hampered a full understanding of disease pathogenesis and development of new treatments. Here we describe a novel CLL cell line (OSU-CLL) generated by EBV transformation, which displays a similar cytogenetic and immunophenotype observed in the patient's CLL (CD5 positive with trisomy 12 and 19). A companion cell line was also generated from the same patient (OSU-NB). This cell line lacked typical CLL characteristics, and is likely derived from the patient's normal B cells. In vitro migration assays demonstrated that OSU-CLL exhibits migratory properties similar to primary CLL cells whereas OSU-NB has significantly reduced ability to migrate spontaneously or towards chemokine. Microarray analysis demonstrated distinct gene expression patterns in the two cell lines, including genes on chromosomes 12 and 19, which is consistent with the cytogenetic profile in this cell line. Finally, OSU-CLL was readily transplantable into NOG mice, producing uniform engraftment by three weeks with leukemic cells detectable in the peripheral blood spleen and bone marrow. These studies describe a new CLL cell line that extends currently available models to study gene function in this disease

Genes identified in Asian SLE GWASs are also associated with SLE in Caucasian populations

Recent genome-wide association studies (GWASs) conducted in Asian populations have identified novel risk loci for systemic lupus erythematosus (SLE). Here, we genotyped 10 single-nucleotide polymorphisms (SNPs) in eight such loci and investigated their disease associations in three independent Caucasian SLE case–control cohorts recruited from Sweden, Finland and the United States. The disease associations of the SNPs in ETS1, IKZF1, LRRC18-WDFY4, RASGRP3, SLC15A4, TNIP1 and 16p11.2 were replicated, whereas no solid evidence of association was observed for the 7q11.23 locus in the Caucasian cohorts. SLC15A4 was significantly associated with renal involvement in SLE. The association of TNIP1 was more pronounced in SLE patients with renal and immunological disorder, which is corroborated by two previous studies in Asian cohorts. The effects of all the associated SNPs, either conferring risk for or being protective against SLE, were in the same direction in Caucasians and Asians. The magnitudes of the allelic effects for most of the SNPs were also comparable across different ethnic groups. On the contrary, remarkable differences in allele frequencies between Caucasian and Asian populations were observed for all associated SNPs. In conclusion, most of the novel SLE risk loci identified by GWASs in Asian populations were also associated with SLE in Caucasian populations. We observed both similarities and differences with respect to the effect sizes and risk allele frequencies across ethnicities.Funding Agencies|Knut and Alice Wallenberg Foundation|2011.0073|Swedish Research Council for Medicine and Health|A0280001A0258801A80741201|Swedish Research Council for Science and Technology|90559401|Swedish Rheumatism Association||Ragnar Soderbergs Foundation||King Gustaf V 80-year Foundation||COMBINE, the Swedish Heart-Lung Foundation||Stockholm County Council||Karolinska Institutet (ALF)||Foundation in memory of Clas Groschinsky||Swedish Society of Medicine||Alliance for Lupus Research||Kirkland Scholar Award||NIH|AR044804AR02175AR052300M01 RR-000079|Uppsala University, Uppsala University Hospital||Swedish Council for Research Infrastructures|8057680170374401|</p

Viability OSU-CLL in response to CLL therapeutic agents.

<p><b>A</b>. Viability of OSU-CLL either untreated (media), treated with vehicle control (DMSO), or increasing doses of chlorambucil (<b>A</b>), fludarabine (<b>B</b>) and dexamethasone (<b>C</b>) for 48 hours determined by MTS (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) assay. <b>D</b>. Viability at 48 hours in response to the indicated therapeutic antibodies was determined by AnnexinV/ propidium iodide (Ann/PI) staining. Antibodies were used as a concentration of 10 µg/mL in the presence of 50 µg/mL anti-Fc crosslinking antibody. Abbreviations: Trastuzumab (Tras, HER2), Rituximab and Ofatumumab (Ritux and Ofa, CD20) and Alemtuzumab, (Alem, CD52). All results shown are representative of 4 independent experiments.</p

Molecular characterization of OSU-CLL and OSU-NB cell lines.

<p>Analysis is performed in patient sample from which the cell lines were derived as well as cultured cells from both lines (approximate timing: early = 3 months, intermediate = 6 months, late = 9 months). <b>A</b>. <b>Flow cytometric analysis for CLL related surface molecules</b>. Flow cytometric analysis for selected B-cell markers, shown as the percent of cells positive. <b>B</b>. <b>Fluorescence in situ hybridization</b>. Interphase FISH analysis for a panel of cytogenetic abnormalities associated with CLL: trisomy 12 (centromere), del(13q14) (D13S319), del(11q22.3) (ATM), del(17p13.1) (TP53), t(11;14) (CCND1-IGH fusion), +8 (MYC), +3 (BCL6), and del(6q22.3) (c-MYB). <b>C</b>. <b>Karyotype analysis</b>. Metaphase karyotype analysis to determine any additional chromosomal abnormalities not identified by FISH analysis.</p

OSU-CLL and OSU-NB exhibit differential <i>in vitro</i> migration properties towards chemokine.

<p>Cells were suspended (5 x 10⁶ cells/mL) and placed in the upper well of 24-well transwell plates. The bottom wells contained either media alone, or media with recombinant CXCL12 (200 ng/mL) or CXCL13 (1000 ng/mL). Cells in the lower chamber were collected after 3 hours; percent migration is calculated relative to the input.</p

Mutational status in OSU-CLL and OSU-NB cell lines.

<p>Analysis is performed in patient sample from which the cell lines were derived as well as cultured cells from both lines (approximate timing: early = 3 months, intermediate = 6 months, late = 9 months). <b>A</b>. <b>IGHV mutational status</b>. Gene mutational status (relative to the reference genome), and immunoglobulin gene usage determined by sequence analysis. <b>B</b>. <b>Somatic gene mutation status</b>. Existence of mutations for common CLL variants was explored by sequence analysis.</p

Impacts of multiple stressors on freshwater biota across spatial scales and ecosystems: MARS Synthesis Paper

Climate and land-use change drive a suite of stressors that shape ecosystems and interact to yield complex ecological responses (that is, additive, antagonistic and synergistic effects). We know little about the spatial scales relevant for the outcomes of such interactions and little about effect sizes. These knowledge gaps need to be filled to underpin future land management decisions or climate mitigation interventions for protecting and restoring freshwater ecosystems. This study combines data across scales from 33 mesocosm experiments with those from 14 river basins and 22 cross-basin studies in Europe, producing 174 combinations of paired-stressor effects on a biological response variable. Generalized linear models showed that only one of the two stressors had a significant effect in 39% of the analysed cases, 28% of the paired-stressor combinations resulted in additive effects and 33% resulted in interactive (antagonistic, synergistic, opposing or reversal) effects. For lakes, the frequencies of additive and interactive effects were similar for all spatial scales addressed, while for rivers these frequencies increased with scale. Nutrient enrichment was the overriding stressor for lakes, with effects generally exceeding those of secondary stressors. For rivers, the effects of nutrient enrichment were dependent on the specific stressor combination and biological response variable. These results vindicate the traditional focus of lake restoration and management on nutrient stress, while highlighting that river management requires more bespoke management solutions.JRC.D.2-Water and Marine Resource