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Transforming growth factor-ß1 (TGF-ß1), a cytokine with immunosuppressive and pro-fibrogenic activity, is a potential marker of infection, liver transplant rejection, and fibrosis. Its levels in the blood and tissues depend on many factors; however, the role of gene polymorphism is still unclear. In this work, the distribution frequency of three single nucleotide polymorphism (SNP) variants of the Tgfb1 gene, namely rs1800469, rs1800470, and rs1800471, was studied in children with end-stage liver disease (ESLD). The study included 225 pediatric liver recipients aged 1 month to 16 years (median, 8 months), including 100 boys and 125 girls, and 198 healthy individuals aged 32.7 ± 9.6 years, including 78 men and 120 women. The indication for liver transplantation in children was ESLD, which was mostly caused by congenital and inherited liver diseases. SNPs were detected by real-time polymerase chain reaction using TaqMan probes and DNA isolated from peripheral blood. SNP frequency distribution was in Hardy-Weinberg equilibrium and did not differ between children with liver diseases and the healthy ones. Analysis of the SNPs frequency based on allelic interaction models did not reveal any differences between patients and the healthy individuals. Evaluation of linkage disequilibrium for Tgfb1 polymorphic variant pairs revealed a statistically significant linkage between all studied variants. Seven haplotypes, which are variants of SNP combinations, were observed in the studied groups of patients and healthy individuals. A total of 80% of the group had three haplotypes, whose frequencies did not differ between patients and the healthy individuals. Significant differences were found in the frequency of the haplotypes A-A-C, G-G-C, and G-A-G (at rs1800469, rs1800470, and rs1800471, respectively), which were observed up to 11 times more often in recipients compared to the healthy individuals. It is possible that these haplotypes are ESLD-predisposing variants, which may also contribute to the development of complications after liver transplantation in children.

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Effect of acetylsalycilic acid (aspirin; Ron-Pulenk) on activity of mouse neutrophil peroxydase system was investigated. Using luminol-dependent chemiluminscence and cytochemical methods we demonstrated that neutrophil peroxydase system in mice receiving aspirin for 14 days is probably determined by stimulation of myeloperoxydase synthesis.

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The effect of SO3(2-), S(2-), NOs(-), and NH4(+) on activity of the peroxidase-hydrogen peroxide system in human peripheral blood neutrophils was studied by the cytochemical method. We showed that the effect of these xenobiotics on neutrophils is similar to that on plants.

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Activity of the peroxidase-hydrogen peroxide system is proposed as a biological marker of ecological risk of heavy metal contamination of the environment. The effect of lead, copper, mercury, and cadmium ions on peroxidase system activity in human peripheral blood neutrophils was studied using cytochemical methods. A possible mechanism of suppression of peroxidase system activity by metal ions is discussed.

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The transformation of nascent phagosomes into forms capable of interacting with antimicrobial organelles of phagocytes, peroxisomes, depends on certain interactions between phagosomes and other vacuolar organelles. Phagosomes repeatedly interact with early and late endosomes through temporary contacts, which allows them to gain and lose complex sets of proteins. In addition, certain polypeptides are eliminated from phagosomes through recycling. New proteins enter phagosomes from the organelles of the biosynthetic pathway or are recruited from the cytoplasm. In addition, phagosomes receive proteins in the process of interaction with endosomes. The overall result of such transformation is acquiring new properties that make possible their interaction with peroxisomes.

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Myeloperoxidase is the main peroxisomal protein of neutrophils, monocytes, and a subpopulation of tissue macrophages; it plays the key role in protective and inflammatory responses of the organism. This role is mediated by various diffusible radicals formed during oxidative reactions catalyzed by the enzyme heme. Myeloperoxidase and nitric oxide synthase are stored in peroxisomes. Nitric oxide reacts with the heme of myeloperoxidase. Low nitric oxide concentrations increase peroxidase activity through reduction of Compound II to native myeloperoxidase. Conversely, high nitric oxide concentrations inhibit the catalytic activity of myeloperoxidase through formation of inactive nitrosyl-heme complexes. Such effect of nitric oxide on catalytic activity of myeloperoxidase has various consequences for infectious and local inflammatory processes. Another oxide of nitrogen, nitrite, is a good substrate for myeloperoxidase Compound I but slowly reacts with Compound II. Nitrogen dioxide is formed after nitrite oxidation by myeloperoxidase. Formation of nitrogen dioxide is another protective mechanism and nitration of microbial proteins by myeloperoxidase can represent an additional protective response of peroxisomes.

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The neutrophil contains numerous granules of various composition and structure. For decades, the neutrophil was believed to contain only two granule types, peroxisomes (peroxidase-positive granules) and neutralohydrolasosomes (peroxidase-negative granules). Later existence of the third type distinguished by the presence of gelatinase hydrolyzing collagen and gelatin. Gelatinase was found in the granules that are lighter as compared to neutralohydrolasosomes and represent a subpopulation of peroxidase-negative granules. In addition to gelatinase, these granules contain beta-2 microglobulin, cytochrome b558, as well as receptor and adhesion proteins. Upon stimulation by inflammatory mediators, the gelatinase granules are secreted faster than the neutralohydrolasosomes. Their exocytosis mediates delivery of new adhesion proteins to the plasma membrane, which is required for maintenance of permanent and fast cell adhesion to the endothelium. The released gelatinase allows the neutrophil to penetrate through the basement membrane of the endothelium.

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Peroxisomal myeloperoxidase plays a key role in synthesis of oxidants by neutrophilic leukocytes. This heme protein consists of two subunits connected by a disulfide bond. The enzyme uses H2O2 and Cl- for synthesis of HOCl--the major oxidant produced by neutrophils. Besides the chlorination reaction, myeloperoxidase exhibits some other properties depending on its oxidation state. The enzyme significantly affects synthesis of oxidants in the cells depending on the competing substrate concentrations and other factors. O2.- is also a physiological substrate of myeloperoxidase. Its reaction with the enzyme determines how the cells utilize O2.- for pathogen elimination. O2.- affects the chlorinating and peroxidase activities of myeloperoxidase. In addition, O2.- reacts with the enzyme yielding the catalytically active compound III that hydroxylates phenols.

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Safety, tolerability and antihypertensive efficacy of a cardioselective beta-blocker nebivolol was studied in 30 patients with mild and moderate hypertension and concomitant stage I chronic obstructive bronchitis. Nebivolol (5 mg/day) was given for 1 month; in 5 patients complementary hydrochlorothiazide (12.5 mg/day) was required for sufficient antihypertensive effect. Nebivolol was well tolerated (only 1 patient complained of head ache), did not cause worsening of bronchitis and spirometric parameters, exerted no cardiodepressive action, and did not induce apparent disturbances of metabolism.

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Myeloperoxidase plays the key role in antimicrobial of phagocytes. This enzyme uses hydrogen peroxide and chloride to catalyze hypochlorous acid formation. HOCl is the most probable agent in the oxygen-dependent bactericidal activity in the phagocyte phagosome. Chlorination markers indicate HOCl generation in the quantities lethal for bacteria. Enzymatic assay for myeloperoxidase indicates proceeding of other reactions involved in bactericidal activity. Superoxide integrates many activities of this kind and is important for physiological function of myeloperoxidase. Elucidation of phagosomes biochemistry can help us to understand why certain pathogens survive in such unfavorable environment.

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Myeloperoxidase plays the key role in antimicrobial oxygen-dependent activity of neutrophils. This heme-containing enzyme catalyzes HOCl formation from H2O2 and Cl-. HOCl is a strong oxidation agent produced at the significant level by neutrophils. Myeloperoxidase easily oxidizes thiocyanate to hypothiocyanate and Br- to HOBr, which are involved in protective reactions. Myeloperoxidase reacts quickly with nitric oxide and peroxynitrite in inflammation foci. All these reactions affect neutrophil-induced oxidative stress.

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The effect of rare metal ions on the activity of the peroxidase system in Pisum sativum L. roots was studied by luminol-dependent chemiluminescence. Trivalent ions of scandium, gallium, indium, and lanthanum, to different extents, inhibit the chemiluminescence of damaged P. sativum roots. A decreased generation of superoxide due to the formation of the complex between metal ions and NADP can underlie the inhibited activity of peroxidase system. The possible mechanism of inhibition of the peroxidase system activity by metal ions is discussed.

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Data on the existence of organelles, binding and inactivating xenobiotics on the subcellular level in animal and plant cells is presented. The morphology of these organelles both the enzymatic constituents and their expected physiological function in immunological homeostasis are discussed. The data presented suggests that the previously discussed organelles such as chloragosomes, cadmosomes, metallogranules, keratinosomes, lamellar and myeloid bodies of animal and plant cells belong to the united class of organelles--antixenosomes which segregate, bind and inactivate xenobiotics protecting both cells and the entire organism from their harmful effect.

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Functional properties of peroxidase-containing granules (peroxidasosomes) of eosinophiles are discussed. Findings are reported on the activities of peroxidase systems and of non-enzymic cationic proteins which occur in the eosinophilic peroxidasosomes in normal state and in various pathological states as well as their antimicrobial and antiparasitic activities.

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Findings suggesting a vast variety of non-enzymic cationic proteins and peptides in human and animal leucocytes are reported. These cationic proteins and peptides demonstrate their antimicrobial and cytotoxic properties due to their detergent characteristics and their capacity to change the permeability of cellular wall and membrane by electrostatic interactions. Information on their homology with some serine proteases is presented.

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