Functional and epigenetic changes in monocytes from adults immunized with an AS01-adjuvanted vaccine.

The adjuvant AS01 plays a key role in the immunogenicity of several approved human vaccines with demonstrated high efficacy. Its adjuvant effect relies on activation of the innate immune system. However, specific effects of AS01-adjuvanted vaccines on innate cell function and epigenetic remodeling, as described for Bacille Calmette-Guérin (BCG) and influenza vaccines, are still unknown.

HIV-related immune activation attenuates polyfunctional IgG and memory B-cell responses to Tdap immunization during pregnancy.

Background: Maternal pertussis vaccination with Tdap vaccine is recommended to protect newborns from severe postnatal infection. HIV-exposed uninfected (HEU) infants have a higher incidence of pertussis infection and may particularly benefit from maternal immunization. The impact of HIV infection on the quality of IgG and memory B cell (MBC) responses to Tdap vaccination in pregnant women (PW) living with HIV (PWH) is unknown.

Impact of pregnancy on polyfunctional IgG and memory B cell responses to Tdap immunization.

Background: Maternal pertussis immunization using Tdap vaccine is recommended in many countries to protect newborns from severe post-natal infection. Immunological changes during pregnancy may influence the response to vaccines. The quality of IgG and memory B cell responses to Tdap immunization in pregnant women has not yet been described.

Safety, tolerability, and immunogenicity of inactivated poliovirus vaccine with or without E.coli double mutant heat-labile toxin (dmLT) adjuvant in healthy adults; a phase 1 randomized study.

Background: Inactivated trivalent poliovirus vaccine (IPV) induces humoral immunity, which protects against paralytic poliomyelitis but does not induce sufficient mucosal immunity to block intestinal infection. We assessed the intestinal immunity in healthy adults in Belgium conferred by a co-formulation of IPV with the mucosal adjuvant double mutant Labile Toxin (dmLT) derived from Escherichia coli.

Methods: Healthy fully IPV-vaccinated 18-45-year-olds were randomly allocated to three groups: on Day 1 two groups received one full dose of IPV (n = 30) or IPV + dmLT (n = 30) in a blinded manner, and the third received an open-label dose of bivalent live oral polio vaccine (bOPV types 1 and 3, n = 20).

Effector Vγ9Vδ2 T cell response to congenital Toxoplasma gondii infection.

A major γδ T cell population in human adult blood are the Vγ9Vδ2 T cells that are activated and expanded in a TCR-dependent manner by microbe-derived and endogenously derived phosphorylated prenyl metabolites (phosphoantigens). Vγ9Vδ2 T cells are also abundant in human fetal peripheral blood, but compared with their adult counterparts they have a distinct developmental origin, are hyporesponsive toward in vitro phosphoantigen exposure, and do not possess a cytotoxic effector phenotype. In order to obtain insight into the role of Vγ9Vδ2 T cells in the human fetus, we investigated their response to in utero infection with the phosphoantigen-producing parasite Toxoplasma gondii (T.

A phase I, dose-escalation study of the novel Polo-like kinase inhibitor volasertib (BI 6727) in patients with advanced solid tumours.

Background: Volasertib (BI 6727) is a potent and selective cell-cycle kinase inhibitor that induces mitotic arrest and apoptosis by targeting Polo-like kinase (Plk). This phase I dose-escalation study evaluated the maximum tolerated dose (MTD) of volasertib, safety and efficacy, and pharmacokinetic (PK) parameters.

Methods: This trial followed an open-label, toxicity-guided dose-titration design.

Biochemistry and site-directed mutational analysis of Delta7-sterol-C5(6)-desaturase.

This report describes recent work on the process of desaturation at C5(6) of sterol precursors in plants. Biochemical characterization of the plant Delta(7)-sterol C5(6)-desaturase (5-DES) indicates that the enzyme system involved shows important similarities to the soluble and membrane-bound non-haem iron desaturases found in eukaryotes, including cyanide and hydrophobic chelators sensitivity, CO resistance and a requirement for exogenous reductant and molecular oxygen. Site-directed mutational analysis of highly conserved residues in 5-DES indicated that eight histidine residues from three histidine-rich motifs were essential for the catalysis, possibly by providing the ligands for a putative Fe centre.

Role of highly conserved residues in the reaction catalyzed by recombinant Delta7-sterol-C5(6)-desaturase studied by site-directed mutagenesis.

The role of 15 residues in the reaction catalyzed by Arabidopsis thaliana Delta7-sterol-C5(6)-desaturase (5-DES) was investigated using site-directed mutagenesis and expression of the mutated enzymes in an erg3 yeast strain defective in 5-DES. The mutated desaturases were assayed in vivo by sterol analysis and quantification of Delta5,7-sterols. In addition, the activities of the recombinant 5-DESs were examined directly in vitro in the corresponding yeast microsomal preparations.

IGF-1 or insulin, and the TSH cyclic AMP cascade separately control dog and human thyroid cell growth and DNA synthesis, and complement each other in inducing mitogenesis.

The regular doubling of cell mass, and therefore of cell protein content, is required for repetitive cell divisions. Preliminary observations have shown that in dog thyrocytes insulin induces protein accumulation but not DNA synthesis, while TSH does not increase protein accumulation but triggers DNA synthesis in the presence of insulin. We show here that EGF and phorbol myristate ester complement insulin action in the same way.

Identification, characterization, and partial purification of 4 alpha-carboxysterol-C3-dehydrogenase/ C4-decarboxylase from Zea mays.

A microsomal preparation from seedlings of Zea mays catalyzed the NAD+-dependent oxidative decarboxylation of several substrates, including 4alpha-carboxy-cholest-7-en-3beta-ol, synthesized according to a new procedure, giving the first in vitro evidence for this enzymatic activity in a higher plant. A GC assay has been developed to detect the Delta7-cholestenone produced and the kinetic parameters of the microsomal system have been established. 4alpha-Carboxysterol decarboxylation shows an exclusive requirement for an oxidized pyridine nucleotide, with NAD+ being more efficient than NADP+.

Optimized expression and catalytic properties of a wheat obtusifoliol 14alpha-demethylase (CYP51) expressed in yeast. Complementation of erg11Delta yeast mutants by plant CYP51.

CYP51s form the only family of P450 proteins conserved in evolution from prokaryotes to fungi, plants and mammals. In all eukaryotes, CYP51s catalyse 14alpha-demethylation of sterols. We have recently isolated two CYP51 cDNAs from sorghum [Bak, S.

Antiproliferative effects of SR31747A in animal cell lines are mediated by inhibition of cholesterol biosynthesis at the sterol isomerase step.

SR31747A is a new sigma ligand exhibiting immunosuppressive properties and antiproliferative activity on lymphocyte cells. Only two subtypes of sigma receptor, namely the sigma1 receptor and emopamil-binding protein, have been characterised molecularly. Only the sigma1 receptor has been shown to bind (Z)N-cyclohexyl-N-ethyl-3-(3-chloro4-cyclohexylphenyl)pro pen-2-ylamine hydrochloride (SR31747A) with high affinity.

The role of cytochrome b5 in 4alpha-methyl-oxidation and C5(6) desaturation of plant sterol precursors.

The electron donors for the membrane-bound sterol-4alpha-methyl-oxidases and sterol C5(6)-desaturase of plant sterol biosynthesis have not been previously identified. The requirement of cytochrome b5 to shuttle reducing equivalents from NAD(P)H to 4,4-dimethylsterol-4alpha-methyl oxidase (4,4-DMSO), 4alpha-methylsterol-4alpha-methyl oxidase (4alpha-MSO), and delta7-sterol-C5(6) desaturase (5-DES) was investigated using a purified preparation of IgG raised against plant cytochrome b5. The activities of 4,4-DMSO, 4alpha-MSO, and 5-DES, three oxidative reactions not mediated by cytochrome P-450, were strongly and completely inhibited by the antibody in a microsomal preparation from maize.

Cloning and functional expression in yeast of a cDNA coding for an obtusifoliol 14alpha-demethylase (CYP51) in wheat.

Screening of a wheat cDNA library with an heterologous CYP81B1 probe from Helianthus tuberosus led to the isolation of a partial cDNA coding a protein with all the characteristics of a typical P450 with high homology (32-39% identity) to the fungal and mammalian CYP51s. Extensive screening of several wheat cDNA libraries isolated a longer cDNA (W516) coding a peptide of 453 amino acids. Alignment of W516 with other P450 sequences revealed that it was missing a segment corresponding to the N-terminal membrane anchor of the protein.

Regulation and metabolic role of phospholipase D activity in human thyroid and cultured dog thyrocytes.

The actions of TSH, ATP, the ionophore A23187, the endoplasmic reticulum Ca(2+)-ATPase inhibitor thapsigargin, and phorbol dibutyrate (PDBu) on 3H-cytidine-monophosphate phosphatidic acid (3H-CMP-PA) accumulation were studied in human thyroid slices to evaluate PA generation and inositol recycling towards phosphatidyl-inositol synthesis. The effects of the same agonists also were measured on phosphatidylbutanol (PtdBut) generation in 3H-palmitate or 3H-myristate prelabeled slices to assess the activity of phospholipase D (PLD). The phospholipid target of this PLD was determined on 3H-choline prelabeled human thyroid slices by measuring 3H-choline release in incubation medium and slices and 3H-choline incorporation in phospholipids.

Emopamil-binding protein, a mammalian protein that binds a series of structurally diverse neuroprotective agents, exhibits delta8-delta7 sterol isomerase activity in yeast.

Delta8-delta7 sterol isomerase is an essential enzyme on the sterol biosynthesis pathway in eukaryotes. This endoplasmic reticulum-resident membrane protein catalyzes the conversion of delta8-sterols to their corresponding delta7-isomers. No sequence data for high eukaryote sterol isomerase being available so far, we have cloned a murine sterol isomerase-encoding cDNA by functional complementation of the corresponding deficiency in the yeast Saccharomyces cerevisiae.

Sterol biosynthesis: strong inhibition of maize delta 5,7-sterol delta 7-reductase by novel 6-aza-B-homosteroids and other analogs of a presumptive carbocationic intermediate of the reduction reaction.

A series of mono- and diazasteroids have been synthesized as analogs of a predicted carbocationic intermediate of delta 5,7-sterol delta 7-reductase (delta 7-SR). 6-Aza-B-homo-5 alpha-cholest-7-en-3 beta-ol (4), a novel compound whose synthesis is described for the first time, and 6,7-diaza-5 alpha-cholest-8(14)-en-3 beta-ol (6) were shown to be very powerful inhibitors of delta 7-SR in a preparation isolated from maize (Zea mays) (K(i),app = 50-70 nM, Ki,app/Km,app = 1.0 x 10(-4) to 1.

The immunosuppressant SR 31747 blocks cell proliferation by inhibiting a steroid isomerase in Saccharomyces cerevisiae.

SR 31747 is a novel immunosuppressant agent that arrests cell proliferation in the yeast Saccharomyces cerevisiae, SR 31747-treated cells accumulate the same aberrant sterols as those found in a mutant impaired in delta 8- delta 7-sterol isomerase. Sterol isomerase activity is also inhibited by SR 31747 in in vitro assays. Overexpression of the sterol isomerase-encoding gene, ERG2, confers enhanced SR resistance.

Plant sterol biosynthesis: identification and characterization of higher plant delta 7-sterol C5(6)-desaturase.

Microsomes obtained from maize seedlings catalyzed the introduction of the delta5-bond into delta7-sterols to yield the corresponding delta 5,7-sterols. Enzymatic bioassay conditions have been developed for the first time for delta 7-sterol C5(6)-desaturase in photosynthetic organisms. The properties of the microsomal system have been studied and the kinetics of the desaturation reaction has been established.

Dissociation of the stimuli for cell hypertrophy and cell division in the dog thyrocyte: insulin promotes protein accumulation while TSH triggers DNA synthesis.

Thyrotropin through the cyclic AMP cascade, and in the presence of insulin or IGF-1, activates the proliferation of dog thyroid cells. In this work it is shown that insulin, presumably acting through the IGF-1 receptors, stimulates the accumulation of protein and increases cell mass but does not induce DNA synthesis. TSH, on the contrary, induces DNA synthesis, in the presence of insulin, but not protein accumulation.

Plant sterol biosynthesis: identification of a NADPH dependent sterone reductase involved in sterol-4 demethylation.

Microsomes obtained from maize embryos were shown to catalyze the reduction of various sterones to produce stereoselectively the corresponding 3 beta-hydroxy derivatives. Enzymatic assay conditions have been developed to characterize this reduction step and the kinetics of the microsomal system has been established. Sterone reduction shows exclusive dependence on NADPH and is inactive with NADH.

Mitogenic, dedifferentiating, and scattering effects of hepatocyte growth factor on dog thyroid cells.

Hepatocyte growth factor (HGF)/scatter factor (SF) is a potent mitogenic factor or motility factor in different cells, acting through the tyrosine kinase receptor encoded by the met protooncogene. In the present work, we demonstrate the powerful mitogenic activity of this growth factor on dog thyroid cells in primary culture. This effect, maximal at 50 ng/ml, was superior to those of other thyroid mitogenic agents, such as TSH, forskolin, and epidermal growth factor (EGF).

Intrathyroidal cytokine gene expression profiles in autoimmune thyroiditis.

Cytokines are thought to mediate the initiation and perpetuation of autoimmune thyroiditis. However, this concept is mainly based on in vitro findings and to date only interleukin (IL)-6 and interferon-gamma (IFN-gamma) have been detected in Graves' disease in vivo. The cytokine pattern produced by T-helper (Th) cells has important regulatory effects on the nature of the immune response.