A new role for PGRP-S (Tag7) in immune defense: lymphocyte migration is induced by a chemoattractant complex of Tag7 with Mts1.

PGRP-S (Tag7) is an innate immunity protein involved in the antimicrobial defense systems, both in insects and in mammals. We have previously shown that Tag7 specifically interacts with several proteins, including Hsp70 and the calcium binding protein S100A4 (Mts1), providing a number of novel cellular functions. Here we show that Tag7-Mts1 complex causes chemotactic migration of lymphocytes, with NK cells being a preferred target.

Structures of three different neutral polysaccharides of Acinetobacter baumannii, NIPH190, NIPH201, and NIPH615, assigned to K30, K45, and K48 capsule types, respectively, based on capsule biosynthesis gene clusters.

Neutral capsular polysaccharides (CPSs) were isolated from Acinetobacter baumannii NIPH190, NIPH201, and NIPH615. The CPSs were found to contain common monosaccharides only and to be branched with a side-chain 1→3-linked β-d-glucopyranose residue. Structures of the oligosaccharide repeat units (K units) of the CPSs were elucidated by 1D and 2D (1)H and (13)C NMR spectroscopy.

Structure of the neutral capsular polysaccharide of Acinetobacter baumannii NIPH146 that carries the KL37 capsule gene cluster.

Capsular polysaccharide (CPS) was isolated from Acinetobacter baumannii NIPH146, and the following structure of branched pentasaccharide repeating unit was established by sugar analyses along with 1D and 2D NMR spectroscopy: In comparison to most other known capsular polysaccharides of A. baumannii, the CPS studied is neutral and lacks any specific monosaccharide component. The synthesis, assembly and export of this structure could be attributed to genes in a novel capsule biosynthesis gene cluster, designated KL37, which was found in the NIPH146 genome.

Structure of a new pseudaminic acid-containing capsular polysaccharide of Acinetobacter baumannii LUH5550 having the KL42 capsule biosynthesis locus.

The capsular polysaccharide from Acinetobacter baumannii LUH5550 was studied by 1D and 2D (1)H and (13)C NMR spectroscopy. The following structure of the branched trisaccharide repeating unit was established: [structure: see text] where Pse5Ac7RHb indicates 5-acetamido-3,5,7,9-tetradeoxy-7-[(R)-3-hydroxybutanoylamino]-L-glycero-L-manno-non-2-ulosonic acid. The genes in the capsule biosynthesis locus designated KL42 are consistent with the structure established.

Liquid but durable: molecular dynamics simulations explain the unique properties of archaeal-like membranes.

Archaeal plasma membranes appear to be extremely durable and almost impermeable to water and ions, in contrast to the membranes of Bacteria and Eucaryota. Additionally, they remain liquid within a temperature range of 0-100°C. These are the properties that have most likely determined the evolutionary fate of Archaea, and it may be possible for bionanotechnology to adopt these from nature.

Structure of the capsular polysaccharide of Acinetobacter baumannii ACICU containing di-N-acetylpseudaminic acid.

Capsular polysaccharide was isolated by the phenol-water extraction of Acinetobacter baumannii ACICU cells and studied by sugar analysis, partial acid hydrolysis, and 1D and 2D (1)H and (13)C NMR spectroscopy. The polysaccharide was found to contain 5,7-diacetamido-3,5,7,9-tetradeoxy-l-glycero-l-manno-non-2-ulosonic or di-N-acetylpseudaminic acid (Pse5Ac7Ac), and the following structure of the branched tetrasaccharide repeating unit was established: The genes present in the polysaccharide gene cluster of A. baumannii ACICU are appropriate to the structure established.

Evaluation of immune response and protective effect of four vaccines against the tick-borne encephalitis virus.

Among three main subtypes of the tick-borne encephalitis virus (TBEV), the Siberian subtype is currently dominant in a majority of the endemic regions of Russia. However, inactivated vaccines are based on TBEV strains of the heterologous Far Eastern or the European subtypes isolated 40-77 years ago. To analyze the efficacy of the available vaccines against currently prevailing TBEV isolates of the Siberian subtype, mice were immunized subcutaneously three times (one group per each vaccine).

Improvement of cardiac contractile function in rats with postinfarction cardiosclerosis after transplantation of mononuclear and multipotent stroma bone marrow cells.

We compared the efficiency of autologous mononuclear cells and multipotent stromal cells of the bone marrow after their non-selective intracoronary transplantation on day 30 after acute coronary infarction in rats. Improvement of hemodynamic parameters of myocardial contractility (rates of left ventricular pressure rise and drop) in comparison with the initial values and deceleration of postinfarction prolongation of QRS and QT intervals were observed in rats of the experimental group in contrast to controls in 4 weeks after transplantation. These functional changes were more intensive after transplantation of multipotent stromal cells and were accompanied by more pronounced morphological signs of reverse myocardial remodeling: thickening of the scarred left ventricular wall, shrinkage of the scar, and decrease in left ventricular dilatation index.

Hemodynamic effects of peptide fragments of differentiation factor HLDF.

Hemodynamic activity of peptides from differentiation factor HLDF (promyelocytic HL-60 line) was studied on WKY and SHR-SP rats. Intravenous infusion of the test peptides was accompanied by changes in blood pressure and heart rate, which depended on the structure of peptides and functional activity of the organism and differed in normotensive and hypertensive animals.

Effect of cholinergic and adrenergic receptor blockade on arrhythmogenic activity of endothelin-1 during inhibition of nitric oxide synthesis in awake mice.

We studied the effects of blockade of nicotinic receptors in sympathetic and parasympathetic ganglia (hexamethonium), muscarinic receptors (atropine), and beta1-adrenoceptors (atenolol) on arrhythmogenic activity of endothelin-1 during inhibition of nitric oxide synthesis with Nomega-nitro-L-arginine in NMRI mice. Atropine reduced, while hexamethonium completely abolished the arrhythmogenic effect of endothelin-1 during nitric oxide synthase inhibition. Atenolol potentiated arrhythmogenic activity of Nomega-nitro-L-arginine, but endothelin-1 had no effect on the incidence of arrhythmias under these conditions.

Effects of central endothelin-1 in normotensive and spontaneously hypertensive rats.

Changes in blood pressure and sympathetic nerve activity induced by local injection of endothelin-1 into the rostroventrolateral medulla were studied in narcotized stroke-prone spontaneously hypertensive rats (SHRSP) and normotensive WKY rats. Endothelin-1 produced similar biphasic response in both rat strains: a transient increase in blood pressure and sympathetic nerve activity followed by progressive hypotension and bradycardia. Pretreatment with ETB-receptor antagonist BQ788 inhibited sympathetic activation induced by endothelin-1, while pretreatment with the ETA-receptor antagonist N-acetyl-[D-Trp16]-endothelin-1 abolished the subsequent hypotension.

Effect of beta-endorphin and beta-endorphin-like peptide immunorphin on the growth of human leukemic cells in vitro.

The influence of beta-endorphin and immunorphin on human leukemic cell growth in vitro was studied. It was shown that both peptides increase the growth of T-lymphoblastoid cells in a dose-dependent manner. The effect of these peptides on the 3H-thymidine incorporation into T-lymphoblastoid cell line Jurkat was not reversed by the antagonist of opioid receptor naloxone.

New experimental model of multiple myeloma.

NSO/1 (P3x63Ay 8Ut) and SP20 myeloma cells were inoculated to BALB/c OlaHsd mice. NSO/1 cells allowed adequate stage-by-stage monitoring of tumor development. The adequacy of this model was confirmed in experiments with conventional cytostatics: prospidium and cytarabine caused necrosis of tumor cells and reduced animal mortality.

Role of I(1)-imidazoline receptors and alpha2-adrenoceptors in hemodynamic effects of moxonidine administration into the rostroventrolateral medulla.

Local injection of 4 nmol moxonidine (unilaterally) into the rostroventrolateral medulla of spontaneously hypertensive rats (SHR-SP) decreased mean blood pressure and heart rate by 24+/-3 and 3+/-4%, respectively. Pretreatment with the I1/alpha2-receptor antagonist efaroxan abolished the moxonidine-induced decrease in mean blood pressure, but had no effect on heart rate. Yohimbine blocked hypotension, delayed bradycardia (8 nmol), or completely inhibited the effects of moxonidine (16 nmol).

Study of protein carbonyls in subcellular fractions isolated from liver and spleen of old and gamma-irradiated rats.

Age- and gamma-irradiation-dependent accumulation of oxidatively modified proteins (measured as carbonyl level) was studied in cytoplasm, mitochondria and nuclei isolated from spleen and liver of 4- and 26-month-old rats. The protein carbonyl levels significantly increased with age in all fractions studied. The carbonyl content was found to be two times higher in the nuclei than in the mitochondria and cytoplasm, which may be related to an extensive modification of lysine and arginine residues in histone molecules.

The structure of the O-specific polysaccharide from Thiobacillus ferrooxidans IFO 14262.

Lipopolysaccharide (LPS) was isolated from Thiobacillus ferrooxidans IFO 14262 by the hot phenol-water extraction procedure. The O-specific polysaccharide, liberated from LPS by mild acetic acid hydrolysis, had a branched pentasaccharide repeating-unit composed of D-glucose, L-rhamnose, D-rhamnose, and 3-O-methyl-L-rhamnose in approximate molar ratios of 2:1:1:1. On the basis of methylation analysis, 1H and 13C NMR spectroscopy, including 2D shift-correlated (COSY) and 1D NOE spectroscopy, the structure for the repeating unit of the O-specific polysaccharide was established, and the assumed biological repeating unit indicated.

The structure of the O-specific polysaccharide of Salmonella arizonae O62.

The O-specific polysaccharide was liberated by mild acid hydrolysis of the lipopolysaccharide (LPS) isolated from S. arizonae O62 by phenol-water extraction. The branched hexasaccharide repeating-unit of the O-specific chain of the O62 LPS contained L-rhamnose, 2-acetamido-2-deoxy-D-glucose, and 2-acetamido-2-deoxy-D-galacturonic acid in molar ratios of 4:1:1.

The use of streptavidin-biotin interaction for preparation of reagents for complement-dependent liposome immunoassay of proteins: detection of latrotoxin.

We have developed liposome sensitization by a protein, latrotoxin (LT), using immobilization of biotinylated LT via streptavidin with biotinylated phosphatidylethanolamine contained in liposomes. The use of such liposomes in the complement-dependent homogeneous liposome immune lysis assay (LILA) has allowed us to detect in the test sample as little as 2 micrograms/ml of polyclonal and 50-100 ng/ml of monoclonal IgG and IgM antibodies to LT. LT concentration in solution was determined by inhibition of immune lysis by free LT.

Preparative in vitro mRNA synthesis using SP6 and T7 RNA polymerases.

A method for preparative in vitro mRNA synthesis is presented. The method makes it possible to generate several hundred RNA copies per molecule of linearized DNA template. The protocol is applicable to the synthesis of RNAs of differing lengths (from 200 to 3000 bases), and both SP6 and T7 RNA polymerases can be used.

Functional expression in vitro of bovine visual rhodopsin.

Expression of functionally active bovine visual rhodopsin was achieved by sequential transcription and translation in vitro of rhodopsin gene cDNA with co-translational insertion of the protein into phosphatidylcholine liposomes. The recombinant rhodopsin has functional, spectral and immunochemical properties similar to those of natural rhodopsin from bovine retina. Two mutant rhodopsins, Cys316----Ser and Asp330----Asn, Asp331----Asn, were produced by oligonucleotide-directed mutagenesis.