Diversity arrays technology (DArT) markers in apple for genetic linkage maps

Diversity Arrays Technology (DArT) provides a high-throughput whole-genome genotyping platform for the detection and scoring of hundreds of polymorphic loci without any need for prior sequence information. The work presented here details the development and performance of a DArT genotyping array for apple. This is the first paper on DArT in horticultural trees. Genetic mapping of DArT markers in two mapping populations and their integration with other marker types showed that DArT is a powerful high-throughput method for obtaining accurate and reproducible marker data, despite the low cost per data point. This method appears to be suitable for aligning the genetic maps of different segregating populations. The standard complexity reduction method, based on the methylation-sensitive PstI restriction enzyme, resulted in a high frequency of markers, although there was 52–54% redundancy due to the repeated sampling of highly similar sequences. Sequencing of the marker clones showed that they are significantly enriched for low-copy, genic regions. The genome coverage using the standard method was 55–76%. For improved genome coverage, an alternative complexity reduction method was examined, which resulted in less redundancy and additional segregating markers. The DArT markers proved to be of high quality and were very suitable for genetic mapping at low cost for the apple, providing moderate genome coverage

J Clin Immunol

We report a longitudinal analysis of the immune response associated with a fatal case of COVID-19 in Europe. This patient exhibited a rapid evolution towards multiorgan failure. SARS-CoV-2 was detected in multiple nasopharyngeal, blood, and pleural samples, despite antiviral and immunomodulator treatment. Clinical evolution in the blood was marked by an increase (2–3-fold) in differentiated effector T cells expressing exhaustion (PD-1) and senescence (CD57) markers, an expansion of antibody-secreting cells, a 15-fold increase in γδ T cell and proliferating NK-cell populations, and the total disappearance of monocytes, suggesting lung trafficking. In the serum, waves of a pro-inflammatory cytokine storm, Th1 and Th2 activation, and markers of T cell exhaustion, apoptosis, cell cytotoxicity, and endothelial activation were observed until the fatal outcome. This case underscores the need for well-designed studies to investigate complementary approaches to control viral replication, the source of the hyperinflammatory status, and immunomodulation to target the pathophysiological response. The investigation was conducted as part of an overall French clinical cohort assessing patients with COVID-19 and registered in clinicaltrials.gov under the following number: NCT04262921

Ecological and genetic analysis of copper and streptomycin resistance in Pseudomonas syringae pv. syringae

Strains of Pseudomonas syringae pv. syringae resistant to copper, streptomycin, or both compounds were recovered from symptomless and diseased tissue of four woody hosts in three nurseries in Oklahoma. In strains resistant to copper and streptomycin (Cu^r Sm^r), resistance to both compounds was cotransferred with a single plasmid which was either 68, 190, or 220 kilobase pairs (kb). All Cu^s Sm^r strains contained a 68-kb conjugative plasmid. Cu^r Sm^s, strains contained one plasmid which varied in size from 60 to 73 kb. All conjugative plasmids which transferred streptomycin resistance contained sequences homologous to the strA and strB Sm^r genes from the broad-host-range plasmid RSF1010. The Sm^r determinant was subsequently cloned from a 68-kb Cu^r Sm^r plasmid designated pPSR1. A restriction map detailing the organization of the homologous Sm^r genes from pPSR1 and RSF1010 and cloned Sm^r genes from P. syringae pv. papulans and Xanthomonas campestris pv. vesicatoria revealed the conservation of all sites studied. The Cu^r genes cloned from P. syringae pv. tomato PT23 and X. campestris pv. vesicatoria XV10 did not hybridize to the Cu^r plasmids identified in the present study, indicating that copper resistance in these P. syringae pv. syringae strains may be conferred by a distinct genetic determinant.Peer reviewedPlant Patholog

Recent insights into targeting the IL-6 cytokine family in inflammatory diseases and cancer

The IL-6 family of cytokines consists of IL-6, IL-11, IL-27, IL-31, oncostatin M (OSM), leukaemia inhibitory factor (LIF), ciliary neurotrophic factor (CNTF), cardiotrophin 1 (CT-1) and cardiotrophin-like cytokine factor 1 (CLCF1). Membership of this cytokine family is defined by usage of common β-receptor signalling subunits, which activate various intracellular signalling pathways. Each IL-6 family member elicits responses essential to the physiological control of immune homeostasis, haematopoiesis, inflammation, development and metabolism. Accordingly, distortion of these cytokine activities often promotes chronic disease and cancer; the pathological importance of this is exemplified by the successful treatment of certain autoimmune conditions with drugs that target the IL-6 pathway. Here, we discuss the emerging roles for IL-6 family members in infection, chronic inflammation, autoimmunity and cancer and review therapeutic strategies designed to manipulate these cytokines in disease

Effect of Combined Leukocyte-Poor Platelet-Rich Plasma and Hyaluronic Acid on Bone Marrow–Derived Mesenchymal Stem Cell and Chondrocyte Metabolism

© The Author(s) 2019. Objective: Given the potential applications of combined biologics, the authors sought to evaluate the in vitro effect of combined platelet-rich plasma (PRP) and hyaluronic acid (HA) on cellular metabolism. Design: Bone marrow–derived mesenchymal stem cells (BMSCs) and chondrocytes were obtained from the femurs of Sprague-Dawley rats. An inflammatory model was created by adding 10 ng/mL interleukin-1-beta to culture media. Non-crosslinked high-molecular-weight HA, activated-PRP (aPRP), and unactivated-PRP (uPRP) were tested. Cellular proliferation and gene expression were measured at 1 week. Genes of interest included aggrecan, matrix metalloproteinase (MMP)-9, and MMP-13. Results: Combined uPRP-HA was associated with a significant increase in chondrocyte and BMSC proliferation at numerous preparations. There was a trend of increased chondrocyte aggrecan expression with combined PRP-HA. The greatest and only significant decrease in BMSC MMP-9 expression was observed with combined PRP-HA. While a significant reduction of BMSC MMP-13 expression was seen with PRP and HA-alone, a greater reduction was observed with PRP-HA. MMP-9 chondrocyte expression was significantly reduced in cells treated with PRP-HA. PRP-alone and HA-alone at identical concentrations did not result in a significant reduction. The greatest reduction of MMP-13 chondrocyte expression was observed in chondrocytes plus combined PRP-HA. Conclusions: We demonstrated a statistically significant increase in BMSC and chondrocyte proliferation and decreased expression of catabolic enzymes with combined PRP-HA. These results demonstrate the additive in vitro effect of combined PRP-HA to stimulate cellular growth, restore components of the articular extracellular matrix, and reduce inflammation