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. Cells of either innate immunity (neutrophils and monocytes) or acquired immunity (CD4⁺ and CD8⁺ lymphocytes) can produce this complex, which confirms the close connection between components of the 2 branches of immune response.     

Protection of Lymphocytes Against HIV using Lentivirus Vector Carrying a Combination of <Emphasis Type="Italic">TRIM5α-HRH</Emphasis> Genes and microRNA Against <Emphasis Type="Italic">CCR5</Emphasis>

Gene therapy is considered a promising approach to treating infections caused by human immunodeficiency virus (HIV). One strategy is to introduce antiviral genes into cells in order to impart resistance to HIV. In this work, the antiviral activity of new anti-HIV lentiviral vector pT has been studied. The vector carries a combination that consists of two identical artificial miRNA mic13lg and the TRIM5α-HRH gene. Two mic13lg microRNAs suppress the expression of the CCR5 gene, which encodes the HIV coreceptor and, thus, prevents the penetration of R5-tropic HIV strains into the cell. It has been shown that pT effectively inhibits the expression of CCR5 in both the HT1080 CCR5-EGFP model cell line and in human primary lymphocytes. The second line of protection against R5- and X4-tropic HIV is provided by the TRIM5α-HRH protein, which binds virus capsids after the virus enters the cell. Indeed, when infecting cells of the SupT1 line, which contains four copies of the vector per cell, with the X-4 tropic HIV, more than 1000-fold suppression of viral replication has been observed. The process of generation of the pT vector and conditions of transduction of CD4⁺ lymphocytes were optimized for testing the antiviral activity of the vector on primary human lymphocytes. As a result, the transduction efficiency for the pT vector was 28%. After infection with the R5-tropic strain of the virus, the survival of cells in the culture of lymphocytes with the vector was significantly higher than in the control. However, the complete suppression of HIV replication was not achieved, presumably due to the inadequate fraction of cells that carry the vector in culture. In the future, it is planned to find the best way to enrich the lymphocyte culture with modified cells to increase resistance to HIV.     

Nucleotide sequences of long terminal repeats of the human endogenous retrovirus (LTR HERV-K) on the short arm of chromosome 7: identification,analysis and evaluation of transcriptional activity

Six clones containing long terminal repeat (LTR) sequences of human endogenous retrovirus of the HERV-K family were found in the YAC library (1200 kb) of the short arm of human chromosome 7. The sequence sizes of the three clones corresponded to the full-length LTR (969 bp). The LTR localization was determined using FISH and verified by comparison with the GenBank database. All three DNA fragments containing solitary LTRs were transcribed in normal germline cells (testicular parenchyma tissue). The differences in the expression of these clones in the germline tumor cells (seminoma) were observed.     

Multiple parameter comparative EEG analysis in alcoholism and narcotic dependence

Multiparametric comparative analysis of spatial organization of EEG was carried out in 137 alcoholics and 131 heroin addicts. Common and different deviations from normal EEG (105 control subjects) were found. Global alterations of EEG spatial organization were observed in drug addicts (as compared to alcoholics). Such changes characterized increasing synchronizing effects of mesolimbic and brainstem structures on the brain cortex. The ethanol effects were more specific and asymmetric. Changes in EEG spectral-coherence characteristics were revealed in all frequency band, however, maximal changes took place in the high-frequency theta in drug addicts and in narrow-frequency alpha subranges in alcoholics. Different effects on the high-frequency EEG component (19.00-21.25 Hz) and information-energy index (coherence-to-spectral power ratio) suggest the difference influence of ethanol and heroin on emotional-motivational and cognitive processes as well as the level of consciousness. The obtained data on EEG discrimination of alcoholism and drug addiction (the inverse problem solution) on the basis of "specific" EEG patterns appear to have considerable promise in development of systems of occupational selection.     

EEG spatial characteristics after intense exercises

Subjects performed intense exercises in a teadbahn under conditions of high ambient temperature and humidity. Spatial characteristics of the EEG were estimated. The information value of the time course of the combined index, characteristics of spatial synchronization and entropy of cortical biopotentials as a test for brain reaction to a load and recovery of its functional state was shown. The significance of non-linear relations between brain potentials in the activation of the adaptive and compensation processes was mentioned.     

Identification of signature and primers specific to genus <Emphasis Type="Italic">Pseudomonas</Emphasis> using mismatched patterns of 16S rDNA sequences

Background

Pseudomonas, a soil bacterium, has been observed as a dominant genus that survives in different habitats with wide hostile conditions. We had a basic assumption that the species level variation in 16S rDNA sequences of a bacterial genus is mainly due to substitutions rather than insertion or deletion of bases. Keeping this in view, the aim was to identify a region of 16S rDNA sequence and within that focus on substitution prone stretches indicating species level variation and to derive patterns from these stretches that are specific to the genus.

Results

Repeating elements that are highly conserved across different species of Pseudomonas were considered as guiding markers to locate a region within the 16S gene. Four repeating patterns showing more than 80% consistency across fifty different species of Pseudomonas were identified. The sub-sequences between the repeating patterns yielded a continuous region of 495 bases. The sub-sequences after alignment and using Shanon's entropy measure yielded a consensus pattern. A stretch of 24 base positions in this region, showing maximum variations across the sampled sequences was focused for possible genus specific patterns. Nine patterns in this stretch showed nearly 70% specificity to the target genus. These patterns were further used to obtain a signature that is highly specific to Pseudomonas. The signature region was used to design PCR primers, which yielded a PCR product of 150 bp whose specificity was validated through a sample experiment.

Conclusions

The developed approach was successfully applied to genus Pseudomonas. It could be tried in other bacterial genera to obtain respective signature patterns and thereby PCR primers, for their rapid tracking in the environmental samples.

     

Activity of neurons of the cerebral A5 zone of rat induced by adequate stimulation of muscle afferents: On the control of arterial pressure and respiration during muscle activity

In experiments on 24 anesthetized rats with preserved spontaneous respiration, we first recorded the volley impulse activity of neurons (n = 30) in the brainstem A5 zone, which was induced by periodical stretchings of the forelimb flexors and hindlimb extensors. The frequency of action potentials in such volleys was, on average, 99.7 ± 19.6 sec⁻¹. In the course of this kinesthetic stimulation, along with the activation of “proprioceptive” neurons of the A5 zone, we observed transitory drops in the arterial pressure and increases first recorded the activity of baroceptive neurons in subpial parts of the A5 zone (n = 4); the frequency of their background impulsation was, on average, 25.1 ± 0.8 sec⁻¹. This activity in all cases was transitorily suppressed both upon increases of the blood pressure caused by constriction of the carotid arteries or nociceptive tail stimulation, as well as upon stretching of skeletal muscles. Therefore, we first obtained direct proof that neuronal systems of the A5 zone are involved in integration of visceral and somatic proprioceptive afferent influences. We hypothesize that the physiological role of this mechanism of integration of somatic and visceral information at the level of the A5 zone is directed toward lowering of the arterial pressure and intensification of respiration within the period of intensified motor activity. This mechanism is based on the interaction between “proprioceptive,” baroceptive, and, perhaps, multiceptive neurons within the A5 zone. Neirofiziologiya/Neurophysiology, Vol. 39, No. 6, pp. 443–452, November–December, 2007.     

Analysis of genome instability in offspring of Mayak workers’ families: Minisatellite CEB

Genome instability transmission in offspring was analyzed in order to evaluate the risk of delayed genetic effects of exposure in 95 family triplets in which only fathers experienced prolonged occupational radiation exposure. The mean total preconceptive absorbed dose (TPAD) of external gamma radiation in the paternal gonads was 1.65 ± 0.080 Gy (dose range of 0.57–5.70 Gy), and the mean TPAD of internal alpha radiation from incorporated plutonium-239 in the gonads was 0.0015 ± 0.0003 Gy (dose range 0.000–0.015 Gy). The control group consisted of 50 family triplets in which parents were not occupationally exposed. The mutation process was studied using PCR based on hypervariable minisatellite marker CEB1 (chromosome 2, 2q37.3). The paternal type of inheritance of mutations for minisatellite CEB1 was found in 80% of cases. The analysis revealed a statistically significant increase in minisatellite CEB1 mutations in the common group of families in which fathers experienced prolonged occupational radiation exposure and in the group of families in which fathers were exposed to radiation in a dosage range of 0.5–1.0 Gy as compared to the control, reaching a significance level of p = 0.109 and p = 0.058, respectively. The dose threshold of mutation detection in the offspring of Mayak PA workers was estimated.     

Meiotic analysis of four cross-pollinated generations in a synthetic autotetraploid population of husk tomato (<i>Physalis ixocarpa</i>)

The cultivated husk tomato (Physalis ixocarpa) (2n = 2x = 24) is native from Mexico and Central America and shows a wide genetic variation. Presently, it is the fourth horticultural crop in cultivation surface in Mexico. The working team of this research previously developed an autotetraploid population by using colchicine. The objectives of the present work were to analyze the ploidy level and meiotic behavior of the subsequent generations (C3, C4, C5, C6) from the original (C2) composed only by plants with the duplicated genome from the Rendidora cultivar, and to determine pollen viability. As a diploid control the cultivar Rendidora of P. ixocarpa was used. Ploidy level was determined by flow citometry and meiotic analysis. For the meiotic study, the microsporocytes were prepared by the squash method, stained with carmin and analyzed in diakinesis. Pollen viability was evaluated through 0.01% Buffalo Black staining. The tetraploid condition prevailed through four cross-pollinating generations, maintaining a constant chromosome number 2n = 4x = 48. In diakinesis, the chromosomes of the diploid cultivar were associated into bivalents, whereas in tetraploid plants the chromosomes associated into univalents, bivalents and trivalents. Highly significant differences in bivalent pairing were detected between autotetraploid plants and between generations. Pollen viability did not show significant differences between generations and allowed reproduction. These results indicate that it is possible to develop an autotetraploid cultivar, because the polyploid state is naturally maintained and the plants are fertile. Furthermore, given the differences in bivalent pairing between plants and generations, a response to selection toward meiotic stability is expected.