Influence of ambrosia herbicides treatment on the composition of surface waxes of the next generation plants

У вегетаційному експерименті досліджено особливості складу вуглеводнів поверхневих восків листя рослин наступної генерації, вирощених із насіння, зібраного на контрольних і оброблених гербіцидами рослинах амброзії полинолистої. Встановлено суттєве зростання вмісту високомолекулярних компонентів і зниження вмісту низькомолекулярних компонентів вуглеводнів. Виявлено залежність змін складу вуглеводнів від впливу певних гербіцидів або їх комбінацій. Зроблено припущення про посилення захисних властивостей поверхневих восків ювенільних рослин амброзії через виявлені зміни.В вегетационном эксперименте исследованы особенности углеводородного состава поверх­ност­ных восков листьев растений следующей генерации, выращенных из семян, собранных на контрольных и обработанных гербицидами растениях амброзии полыннолистной. Установлено существенное увеличение содержания высокомолекулярных компонентов и снижение содержания низкомолекулярных углеводородных компонентов. Выявлена зависимость изменений состава углеводородов от влияния определенных гербицидов или их комбинаций. Высказано предположение об усилении защитных свойств поверхностных восков ювенильных растений амброзии вследствие выявленных изменений.In vegetative experiment the peculiarities of hydrocarbons composition of the leaves surface waxes of Ambrosia artemisifolia grown out of seeds from control plants and ones treated by herbicides were studied. The substantial increase of high-molecular hydrocarbons but reduction of low-molecular constituents are established. The dependence of hydrocarbonscomposition changeson the influence of particular herbicides and its combinations is revealed. The enhancing of protective properties of juvenile ambrosia’s surface waxesin consequence of revealed changesis supposed.

Construction of a dengue virus type 4 reporter replicon and analysis of temperature-sensitive mutations in non-structural proteins 3 and 5

Replicon systems have been useful to study mechanisms of translation and replication of flavivirus RNAs. In this study, we constructed a dengue virus 4 replicon encoding a Renilla luciferase (Rluc) reporter, and six single-residue substitution mutants were generated: L128F and S158P in the non-structural protein (NS) 3 protease domain gene, and N96I, N390A, K437R and M805I in the NS5 gene. The effects of these substitutions on viral RNA translation and/or replication were examined by measuring Rluc activities in wild-type and mutant replicon RNA-transfected Vero cells incubated at 35, 37 and 39 °C. Our results show that none of the mutations affected translation of replicon RNAs; however, L128F and S158P of NS3 at 39 °C, and N96I of NS5 at 37 and 39 °C, presented temperature-sensitive (ts) phenotypes for replication. Furthermore, using in vitro methyltransferase assays, we identified that the N96I mutation in NS5 exhibited a ts phenotype for N7-methylation, but not for 2′-O-methylation

Defective Interfering Viral Particles in Acute Dengue Infections

While much of the genetic variation in RNA viruses arises because of the error-prone nature of their RNA-dependent RNA polymerases, much larger changes may occur as a result of recombination. An extreme example of genetic change is found in defective interfering (DI) viral particles, where large sections of the genome of a parental virus have been deleted and the residual sub-genome fragment is replicated by complementation by co-infecting functional viruses. While most reports of DI particles have referred to studies in vitro, there is some evidence for the presence of DI particles in chronic viral infections in vivo. In this study, short fragments of dengue virus (DENV) RNA containing only key regulatory elements at the 3′ and 5′ ends of the genome were recovered from the sera of patients infected with any of the four DENV serotypes. Identical RNA fragments were detected in the supernatant from cultures of Aedes mosquito cells that were infected by the addition of sera from dengue patients, suggesting that the sub-genomic RNA might be transmitted between human and mosquito hosts in defective interfering (DI) viral particles. In vitro transcribed sub-genomic RNA corresponding to that detected in vivo could be packaged in virus like particles in the presence of wild type virus and transmitted for at least three passages in cell culture. DENV preparations enriched for these putative DI particles reduced the yield of wild type dengue virus following co-infections of C6–36 cells. This is the first report of DI particles in an acute arboviral infection in nature. The internal genomic deletions described here are the most extensive defects observed in DENV and may be part of a much broader disease attenuating process that is mediated by defective viruses

ЦИКЛОФИЛИН А: СТРОЕНИЕ И ФУНКЦИИ

Cyclophilins belong to a large family of ancient conservative proteins with peptidyl-prolyl-cis-trans isomerase activity. The main member of this family – cyclophilin A – was discovered as an intracellular ligand for cyclosporine A. Further investigations revealed a wide range of functions of cyclophilin A. Cyclophilin A is involved in T-cell signaling, it takes part in folding, assembly and intracellular transport of proteins, as well as acts as an antioxidant. Different cell types secrete cyclophilin A under infection or oxidative stress. Cyclophilin A is one of the main factors involved in inflammation and pathogenesis of autoimmune, cardiovascular and other diseases. This protein is thought to take part in tumor progression. In this review we describe the structure of cyclophilin A and its main known functions in health and disease.Циклофилины – большое семейство консервативных, филогенетически очень древних белков, обладающих пептидил-пролил-цистранс-изомеразной активностью. Наиболее распространенным среди них является циклофилин А, который был обнаружен как внутриклеточный лиганд для связывания с циклоспорином А. Изучение механизма супрессии циклоспорина А, в основе которой лежит его взаимодействие с циклофилином А, послужило мощным толчком для исследований последнего. Было установлено, что циклофилин А принимает участие в проведении сигналов в Т-лимфоцитах, участвует в фолдинге, сборке и внутриклеточном транспорте белков, а также играет роль антиоксиданта. При инфекциях и оксидативном стрессе различные типы клеток способны секретировать циклофилин А. Он является одним из центральных факторов, участвующих в воспалении и патогенезе аутоиммунных, сердечно-сосудистых и других заболеваний. Предполагается, что циклофилин А может принимать участие в прогрессии опухолей. Настоящий обзор посвящен описанию строения и известных функций циклофилина А в норме и при различных патологических процессах

Характеристика эффекторов адаптивного иммунитета, вовлеченных во вторичный ксеногенный иммунный ответ на клетки меланомы человека

Introduction. Current approaches are being developed for adoptive cancer therapy using T-cells genetically modified with T-cell receptors (TCRs) with specificity for tumor antigens. The complexities of identifying antigen-specific TCRs in a patient’s repertoire and selecting therapeutic  receptors necessitate the development of experimental strategies for generating tumor-specific T cells. One of such approaches could be the xenogeneic immunization of mice with human tumor cells. It seems plausible that the T cell repertoire stimulated by xenogeneic vaccination could be a source of TCRs suitable for adoptive cancer immunotherapy.Aim. To assess the prospects for using xenogeneic immunizations to generate tumor-specific memory T cells and identify their TCRs suitable for adoptive immunotherapy, we studied the dynamics of the secondary xenogeneic response in a model of induction of an immune response in mice to human melanoma cells.Materials and methods. Mice were immunized with human melanoma cells, and 45 days later, they were re-challenged with the immunizing tumor. The dynamics of the development of the secondary immune response in vivo and the composition of the involved effectors of adaptive immunity were analyzed by flow cytometry. The proliferation of lymphocytes from immune mice in response to human melanoma cells was evaluated in in vitro culture.Results. The secondary xenogeneic response was characterized by a more intense accumulation of T cells and the rapid development of the effector phase at the injection site of human melanoma. This correlated with an enhanced in vitro proliferative response of lymphocytes from immune animals to xenoantigens of the immunizing tumor. CD4+ and CD8+ memory  T cells contributed equally to the development of a secondary response to human melanoma cells expressing HLA class I and II molecules. When only HLA class I was expressed on the cells of the immunizing xenogeneic tumor, CD8+ memory cells were formed, which dominated the secondary immune response.Conclusion. Our findings confirmed the formation of a specific immunological memory for xenoantigens during xenogeneic immunization. This suggests the possibility of generating xenogeneic TCRs specific for human tumor antigens, which opens up opportunities to developing approaches for screening among them for receptor variants suited for adoptive immunotherapy of human cancers.Введение. В настоящее  время развиваются подходы адоптивной клеточной терапии онкологических заболеваний с использованием Т-клеток, генетически модифицированных Т-клеточными рецепторами (ТКР) со специфичностью к опухолевым антигенам. Трудоемкость идентификации антигенспецифических ТКР в репертуаре пациента и отбора терапевтических рецепторов делает актуальной разработку экспериментальных стратегий генерации опухолеспецифических Т-клеток. Одной из них может быть ксеногенная иммунизация модельных животных клетками опухоли человека. представляется привлекательной идея, что репертуар Т-клеток, стимулированный  ксеногенной иммунизацией, может стать источником для поиска ТКР, пригодных для адоптивной иммунотерапии опухолей человека.Цель исследования  – анализ динамики вторичного ксеногенного ответа в модели индукции иммунного ответа у мышей на клетки меланомы человека для оценки перспектив использования ксеногенных иммунизаций для генерации опухолеспецифических Т-клеток памяти и идентификации их ТКР, подходящих для адоптивной иммунотерапии.Материалы и методы. Мышей иммунизировали клетками меланомы человека; через 45 дней повторно вводили иммунизирующую опухоль. Динамику развития вторичного иммунного ответа in vivo и состав вовлеченных эффекторов адаптивного иммунитета анализировали методом проточной цитофлуориметрии. В культуре in vitro оценивали пролиферативный ответ лимфоцитов иммунных мышей на клетки иммунизирующей и сторонней меланом человека.Результаты. Вторичный ксеногенный ответ характеризовался более интенсивным накоплением Т-клеток и быстрым развитием эффекторной фазы в месте введения меланомы человека. это коррелировало с усиленным пролиферативным ответом in vitro лимфоцитов иммунных животных на ксеноантигены иммунизирующей опухоли. CD4+- и СD8+-Т-клетки памяти вносили  равный  вклад в развитие вторичного ответа на клетки меланомы человека, экспрессирующей молекулы антигенов гистосовместимости (human leukocyte antigens, HLA) классов I и II. При экспрессии только HLA класса I на клетках иммунизирующей ксеногенной опухоли формировались CD8+-клетки памяти, которые доминировали во вторичном иммунном ответе.Заключение. полученные нами данные подтвердили, что в ходе ксеногенной иммунизации формируется специфическая иммунологическая память к ксеноантигенам. Это указывает на возможность генерации ксеногенных ТКР, специфичных к антигенам опухоли человека, и открывает перспективы для разработки стратегий поиска среди них вариантов рецепторов, пригодных для адоптивной иммунотерапии опухолей человека

Dengue Virus Capsid Protein Usurps Lipid Droplets for Viral Particle Formation

Dengue virus is responsible for the highest rates of disease and mortality among the members of the Flavivirus genus. Dengue epidemics are still occurring around the world, indicating an urgent need of prophylactic vaccines and antivirals. In recent years, a great deal has been learned about the mechanisms of dengue virus genome amplification. However, little is known about the process by which the capsid protein recruits the viral genome during encapsidation. Here, we found that the mature capsid protein in the cytoplasm of dengue virus infected cells accumulates on the surface of ER-derived organelles named lipid droplets. Mutagenesis analysis using infectious dengue virus clones has identified specific hydrophobic amino acids, located in the center of the capsid protein, as key elements for lipid droplet association. Substitutions of amino acid L50 or L54 in the capsid protein disrupted lipid droplet targeting and impaired viral particle formation. We also report that dengue virus infection increases the number of lipid droplets per cell, suggesting a link between lipid droplet metabolism and viral replication. In this regard, we found that pharmacological manipulation of the amount of lipid droplets in the cell can be a means to control dengue virus replication. In addition, we developed a novel genetic system to dissociate cis-acting RNA replication elements from the capsid coding sequence. Using this system, we found that mislocalization of a mutated capsid protein decreased viral RNA amplification. We propose that lipid droplets play multiple roles during the viral life cycle; they could sequester the viral capsid protein early during infection and provide a scaffold for genome encapsidation

A New Model to Produce Infectious Hepatitis C Virus without the Replication Requirement

Numerous constraints significantly hamper the experimental study of hepatitis C virus (HCV). Robust replication in cell culture occurs with only a few strains, and is invariably accompanied by adaptive mutations that impair in vivo infectivity/replication. This problem complicates the production and study of authentic HCV, including the most prevalent and clinically important genotype 1 (subtypes 1a and 1b). Here we describe a novel cell culture approach to generate infectious HCV virions without the HCV replication requirement and the associated cell-adaptive mutations. The system is based on our finding that the intracellular environment generated by a West-Nile virus (WNV) subgenomic replicon rendered a mammalian cell line permissive for assembly and release of infectious HCV particles, wherein the HCV RNA with correct 5′ and 3′ termini was produced in the cytoplasm by a plasmid-driven dual bacteriophage RNA polymerase-based transcription/amplification system. The released particles preferentially contained the HCV-based RNA compared to the WNV subgenomic RNA. Several variations of this system are described with different HCV-based RNAs: (i) HCV bicistronic particles (HCVbp) containing RNA encoding the HCV structural genes upstream of a cell-adapted subgenomic replicon, (ii) HCV reporter particles (HCVrp) containing RNA encoding the bacteriophage SP6 RNA polymerase in place of HCV nonstructural genes, and (iii) HCV wild-type particles (HCVwt) containing unmodified RNA genomes of diverse genotypes (1a, strain H77; 1b, strain Con1; 2a, strain JFH-1). Infectivity was assessed based on the signals generated by the HCV RNA molecules introduced into the cytoplasm of target cells upon virus entry, i.e. HCV RNA replication and protein production for HCVbp in Huh-7.5 cells as well as for HCVwt in HepG2-CD81 cells and human liver slices, and SP6 RNA polymerase-driven firefly luciferase for HCVrp in target cells displaying candidate HCV surface receptors. HCV infectivity was inhibited by pre-incubation of the particles with anti-HCV antibodies and by a treatment of the target cells with leukocyte interferon plus ribavirin. The production of authentic infectious HCV particles of virtually any genotype without the adaptive mutations associated with in vitro HCV replication represents a new paradigm to decipher the requirements for HCV assembly, release, and entry, amenable to analyses of wild type and genetically modified viruses of the most clinically significant HCV genotypes

ФУНКЦИОНАЛЬНЫЙ ПОТЕНЦИАЛ КЛЕТОК ПАМЯТИ CD8+ В УСЛОВИЯХ ЛИМФОПЕНИИ, ВЫЗВАННОЙ ВВЕДЕНИЕМ ГИДРОКОРТИЗОНА

Background. Wide use of glucocorticoids therapy for neoplasms, autoimmune diseases and allergies is associated with suppression of adaptive immunity that requires profound study of their immunoregulatory properties and immunotoxicity.Results. In this work, using our model of selective activation of mouse CD8+ memory cells in the mixed lymphocyte reaction (MLR) in vitro, we show for the first time that intraperitoneal injection of high dose hydrocortisone (2.5 mg per animal) allows to detect memory cells in the thymus of animals immunized with allogeneic tumor cells. Similar to memory cells from other lymphoid organs, hydrocortisone-resistant thymic lymphocytes from immune animals respond on allogeneic stimulators subjected to severe heat shock and are immunologically specific to immunizing alloantigen. Thus, cortisone-resistant thymocytes are partially or completely represented by memory cells. We also show here that memory responses of heterozygotes on TCR a-chain knock-out (genetically incapable to secondary rearrangement of TCR achains) are significantly enhanced as compared with the ones of wild type mice.Conclusion. These findings allows to suggest the hypothesis according to which memory T cell clones proliferating in primary immune response migrate into thymus providing necessary microenvironment for reexpression of recombinases. After editing of genes encoding TCR achains, such T lymphocytes can return to peripheral repertoire maintaining its wideness.Введение. Широкое применение глюкокортикоидов в терапии онкологических, аутоиммунных и аллергических заболеваний сопряжено с подавлением функций адаптивного иммунитета и ставит задачу углубленного исследования их иммунорегуляторных свойств и иммунотоксичности.Результаты. Используя разработанную нами модель селективной активации мышиных клеток памяти CD8+ в смешанной культуре лимфоцитов (mixedlymphocytereaction, MLR) invitro, в этой работе мы впервые показали, что внутрибрюшинное введение мышам гидрокортизона в высокой дозе (2,5 мг на 1 животное) позволяет обнаружить Т-клетки памяти в тимусе животных, иммунизированных клетками  аллогенной опухоли. Как и клетки  памяти из других лимфоидных органов, лимфоциты тимуса иммунных животных, резистентные к гидрокортизону, отвечают пролиферацией на аллогенные стимуляторы, подвергнутые острому тепловому шоку и иммунологически специфичны к иммунизирующему аллоантигену. Таким образом, кортизонрезистентные тимоциты частично или полностью представлены клетками памяти. Также мы показали, что у гетерозигот по нокауту α-цепи TCR (генетически неспособных ко вторичной реаранжировке α-цепей) ответы клеток памяти значительно усилены по сравнению с ответами клеток памяти мышей дикого типа.Заключение. Полученные данные позволяют выдвинуть гипотезу, согласно которой клоны Т-клеток памяти, размножившиеся в первичном иммунном ответе, мигрируют в тимус, обеспечивающий микроокружение, необходимое для реэкспрессии ими рекомбиназ. После завершения редактирования α-цепей TCR такие Т-лимфоциты могут вернуться в периферический репертуар, поддерживая его широту

Antiviral and Neuroprotective Role of Octaguanidinium Dendrimer-Conjugated Morpholino Oligomers in Japanese Encephalitis

Japanese encephalitis (JE) is caused by a flavivirus that is transmitted to humans by mosquitoes belonging to the Culex sp. The threat of JE looms over a vast geographical realm, encompassing approximately 10 billion people. The disease is feared because currently there are no specific antiviral drugs available. There have been reports where other investigators have shown that agents that block viral replication can be used as effective therapeutic countermeasures. Vivo-Morpholinos (MOs) are synthetically produced analogs of DNA or RNA that can be modified to bind with specific targeted regions in a genome. In this study the authors propose that in an animal model of JE, MOs specifically designed to bind with specific region of JE virus (JEV) genome, blocks virus production in cells of living organisms. This results in reduced mortality of infected animals. As the major target of JEV is the nerve cells, analysis of brain of experimental animals, post treatment with MOs, showed neuroprotection. Studies in cultured cells were also supportive of the antiviral role of the MOs. The potent anti-sense effect in animals and lack of obvious toxicity at the effective dosage make these MOs good research reagents with future therapeutic applications in JE

Actual aspects of organic agricultural development in Ukraine

The monograph presents a conceptual analysis of the development of all sectors of organic production in Ukraine, the problems of sustainable increase in the efficiency of agrobiocenoses, the economic aspects of the formation of organic production according to European standards, and the analysis of opportunities for the agrarian sector. The approaches to the application of new methods and tools in organic production are described. The monograph is prezented for specialists, employments of the agrarian sector, scientists, professors, students and masters, all those who are interested in the specified range of questions that are being analyzed