Dissection of the anti-Candida albicans mannan immune response using synthetic oligomannosides reveals unique properties of β-1,2 mannotriose protective epitopes.

Candida albicans mannan consists of a large repertoire of oligomannosides with different types of mannose linkages and chain lengths, which act as individual epitopes with more or less overlapping antibody specificities. Although anti-C. albicans mannan antibody levels are monitored for diagnostic purposes nothing is known about the qualitative distribution of these antibodies in terms of epitope specificity.

Retrospective study of COVID-19 seroprevalence among tissue donors at the onset of the outbreak before implementation of strict lockdown measures in France.

Background The COVID-19 pandemic has altered organ and tissue donations as well as transplantation practices. SARS-CoV-2 serological tests could help in the selection of donors. We assessed COVID-19 seroprevalence in a population of tissue donors, at the onset of the outbreak in France, before systematic screening of donors for SARS-CoV-2 RNA.

How to improve donor skin availability: Pragmatic procedures to minimize the discard rate of cryopreserved allografts in skin banking.

Background: Microbial contamination of human skin allografts is a frequent cause of allograft discard. Our purpose was to evaluate the discard rate of skin bank contaminated allografts and specific procedures used to reduce allograft contamination without affecting safety.

Methods: We conducted at the Lille Tissue Bank a retrospective study of all deceased donors (n = 104) harvested from January 2018 to December 2018.

Benefits of cryopreserved human amniotic membranes in association with conventional treatments in the management of full-thickness burns.

The use of split-thickness skin autografts (STSA) with dermal substitutes is the gold standard treatment for third-degree burn patients. In this article, we tested whether cryopreserved amniotic membranes could be beneficial to the current treatments for full-thickness burns. Swines were subjected to standardised full-thickness burn injuries, and then were randomly assigned to treatments: (a) STSA alone; (b) STSA associated with the dermal substitute, Matriderm; (c) STSA plus human amniotic membrane (HAM); and (d) STSA associated with Matriderm plus HAM.

Chiral separation of new sulfonamide derivatives and evaluation of their enantioselective affinity for human carbonic anhydrase II by microscale thermophoresis and surface plasmon resonance.

The aim of this study was to develop a method combining chiral separation and biophysical techniques to evaluate the enantioselective affinity of original sulfonamide derivatives towards their therapeutic target, the human carbonic anhydrase II (hACII). The first step consisted in the preparation of the enantiomers by chromatographic separation. The performances of HPLC and Supercritical Fluid Chromatography (SFC) were studied at the analytical scale by optimization of various experimental conditions using adsorbed polysaccharide chiral stationary phases (amylose AD-H and cellulose OD-H).

Amine coupling versus biotin capture for the assessment of sulfonamide as ligands of hCA isoforms.

This work was dedicated to the development of a reliable SPR method allowing the simultaneous and quick determination of the affinity and selectivity of designed sulfonamide derivatives for hCAIX and hCAXII versus hCAII, in order to provide an efficient tool to discover drugs for anticancer therapy of solid tumors. We performed for the first time a comparison of two immobilization approaches of hCA isoforms. First one relies on the use of an amine coupling strategy, using a CM7 chip to obtain higher immobilization levels than with a CM5 chip and consequently the affinity with an higher precision (CV% < 10%).

Unconventional surface plasmon resonance signals reveal quantitative inhibition of transcriptional repressor EthR by synthetic ligands.

EthR is a mycobacterial repressor that limits the bioactivation of ethionamide, a commonly used anti-tuberculosis second-line drug. Several efforts have been deployed to identify EthR inhibitors abolishing the DNA-binding activity of the repressor. This led to the demonstration that stimulating the bioactivation of Eth through EthR inhibition could be an alternative way to fight Mycobacterium tuberculosis.

Label-free characterization of carbonic anhydrase-novel inhibitor interactions using surface plasmon resonance, isothermal titration calorimetry and fluorescence-based thermal shift assays.

This work describes the development of biophysical unbiased methods to study the interactions between new designed compounds and carbonic anhydrase II (CAII) enzyme. These methods have to permit both a screening of a series of sulfonamide derivatives and the identification of a lead compound after a thorough study of the most promising molecules. Interactions data were collected using surface plasmon resonance (SPR) and thermal shift assay (TSA).

Resistance of the cell wall to degradation is a critical parameter for isolation of high quality RNA from natural isolates of Bacillus subtilis.

Natural isolates of Bacillus subtilis are known for their ability to produce a large panel of bioactive compounds. Unfortunately, their recalcitrance to conventional molecular techniques limits their transcript studies. In this work, difficulties to isolate RNA attributed to the cell wall were overcome, finally authorising powerful RT-PCR's.

Biotin sulfone as a new tool for synthetic oligosaccharide immobilization: application to multiple analysis profiling and surface plasmonic analysis of anti-Candida albicans antibody reactivity against alpha and beta (1-->2) oligomannosides.

As a part of our glycoantigen synthetic program for diagnosis and basic analysis of yeast-related pathogenic mechanisms, a library of 1-->2 oligomannosides suitable for immunoanalysis was prepared. The use of biotin sulfone, an oxidized form of biotin, offers a convenient solution for both oligosaccharide synthesis and immobilization on microspheres and surface plasmon resonance sensors. The application of this new strategy for the analysis of anti- Candida albicans antibody response through multiple-analyte profiling technology (Luminex) and with surface plasmonic analysis using biotin tagged synthetic oligosaccharides on avidin coated surfaces was validated using monoclonal antibodies.

Phenotype and HFE genotype in a population with abnormal iron markers recruited from an Endocrinology Department.

Objective: The aim of this study was to describe HFE genotype in a population of patients with altered iron markers recruited in an Endocrinology Department and to define the possible phenotype-genotype relationships.

Methods: A total of 156 patients with high serum ferritin concentrations (>300 ng/ml) or transferrin saturation (>45%) (I group), and a control group of 106 healthy subjects (C group) underwent HFE genotyping (classical C282Y and H63D mutations). We also examined the main genetic features of subgroups in I according to the presence (D) or the absence (ND) of diabetes.

Expression of progenitor cell markers during expansion of sorted human pancreatic beta cells.

Functional pancreatic beta cell mass is dynamic and although fully differentiated, beta cells are capable of reentering the cell cycle upon appropriate stimuli. Stimulating regeneration-competent cells in situ is clearly the most desirable way to restore damaged tissue. Regeneration by dedifferentiation and transdifferentiation is a potential source of cells exhibiting a more developmentally immature phenotype and a wide differentiation potential.

Expression of apoptosis regulatory factors during myocardial dysfunction in endotoxemic rats.

Objectives: To document the time course of apoptosis pathway activation in sepsis and to determine whether Bcl-2 overexpression would improve endotoxin-induced myocardial dysfunction and mortality rate.

Design: Randomized, controlled trial.

Setting: Experimental laboratory.

Selective alteration of gene expression in response to natural and synthetic retinoids.

Background: Retinoids are very potent inducers of cellular differentiation and apoptosis, and are efficient anti-tumoral agents. Synthetic retinoids are designed to restrict their toxicity and side effects, mostly by increasing their selectivity toward each isotype of retinoic acids receptors (RARalpha,beta, gamma and RXRalpha, beta, gamma). We however previously showed that retinoids displayed very different abilities to activate retinoid-inducible reporter genes, and that these differential properties were correlated to the ability of a given ligand to promote SRC-1 recruitment by DNA-bound RXR:RAR heterodimers.

AGEs bind to mesothelial cells via RAGE and stimulate VCAM-1 expression.

Background: Excess advanced glycation end-products (AGEs) are formed during renal failure, and AGE formation also may be connected with the high glucose concentration of peritoneal dialysis (PD) fluids. To determine the effect of human peritoneal mesothelial cell (HPMC) exposure to glycated proteins, we studied the HPMC receptor of AGE expression (RAGE), and analyzed the results of AGE-RAGE interaction on adhesion molecule expression and leukocyte binding.

Methods: RAGE was detected by FACS analysis, and RAGE mRNA by reverse transcription-polymerase chain reaction (RT-PCR).