RESUMO
The composition of extracellular vesicles (EVs) is altered in many pathological conditions, and their molecular content provides essential information on features of parent cells and mechanisms of crosstalk between cells and organs. Metabolic Syndrome (MetS) is a cluster of clinical manifestations including obesity, insulin resistance, dyslipidemia and hypertension that increases the risk of cardiovascular disease and type 2 diabetes mellitus. Here, we investigated the crosstalk between liver and adipocytes by characterizing EVs secreted by primary hepatocytes isolated from Zucker rat model, and studied the effect they have on 3T3-L1 adipocytes. We found that steatotic hepatocytes secrete EVs with significantly reduced exosomal markers in comparison with their lean counterpart. Moreover, proteomic analysis revealed that those EVs reflect the metabolic state of the parent cell in that the majority of proteins upregulated relate to fat metabolism, fatty acid synthesis, glycolysis, and pentose phosphate pathway. In addition, hepatocytes-secreted EVs influenced lipolysis and insulin sensitivity in recipient 3T3-L1 adipocytes. Untargeted metabolomic analysis detected alterations in different adipocyte metabolic pathways in cells treated with hepatic EVs. In summary, our work showed that steatosis has a significant impact in the amount and composition of EVs secreted by hepatocytes. Moreover, our data point to the involvement of hepatic-EVs in the development of pathologies associated with MetS.
RESUMO
Distribution of the isoelectric point (pI) was calculated for the hypervariable regions of Fab fragments of the antibody molecules, which structure is annotated in the structural antibody database SabDab. The distribution is consistent with the universal for all organisms dividing the proteome into two sets of acidic and basic proteins. It shows the additional fine structure in a form of the narrow-sized peaks of pI values. This is an explanation why a small change of the environmental pH can have a strong effect on the antibody-antigen affinity. To show this, a typical enzyme-linked immunospecific assay experiment for testing the reaction of goat anti-human IgA antibodies with human IgA immunoglobulins of saliva as antigens was modified in such a way that Fe3O4magnetic nanoparticles were added to PBS buffer. The magnetic nanoparticles were remotely heated by the radio frequency magnetic field providing the local change of temperature and pH. It was observed that short times of the heating were significantly increasing the antibody-antigen binding strength while it was not the case for a longer time. The finding discussed in the study can be useful for biopharmaceuticals using antibodies, the immunoassay techniques as well as for control over the use of hyperthermia.
Assuntos
Anticorpos/química , Reações Antígeno-Anticorpo , Antígenos/química , Temperatura Alta , Fragmentos Fab das Imunoglobulinas/química , Afinidade de Anticorpos , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Concentração de Íons de Hidrogênio , Imunoglobulina A/imunologia , Ponto Isoelétrico , Nanopartículas de Magnetita , Saliva/imunologiaRESUMO
The ability of viable and glutaraldehyde-fixed, stationary-phase yeast cells of Candida albicans to bind concanavalin A and monospecific antiserum for antigenic factor 1 was examined. Both fluorescence flow cytometric analysis and transmission electron microscopy indicated that glutaraldehyde-fixed cells bound less of the two reagents than did unfixed viable cells.
Assuntos
Aldeídos , Antígenos de Fungos/metabolismo , Candida albicans/metabolismo , Glutaral , Receptores de Concanavalina A/efeitos dos fármacos , Antígenos de Fungos/imunologia , Candida albicans/ultraestrutura , Parede Celular/metabolismo , Parede Celular/ultraestrutura , Fixadores , Citometria de Fluxo , Imunofluorescência , Mananas/imunologia , Mananas/metabolismo , Receptores de Concanavalina A/ultraestruturaRESUMO
Mice sensitized with living Sh. flexneri 3a or with outer membrane proteins (OMP) derived from these bacteria showed Arthus and delayed type hypersensitivity (DTH) when injected in the footpad with OMP. The delayed reactivity to OMP was transferable to normal mice by spleen cells obtained from donor animals which were previously sensitized with living bacteria.
Assuntos
Reação de Arthus/etiologia , Hipersensibilidade Tardia/etiologia , Shigella flexneri/imunologia , Animais , Proteínas da Membrana Bacteriana Externa/imunologia , Proteínas da Membrana Bacteriana Externa/isolamento & purificação , Feminino , Imunização , Imunização Passiva , Masculino , Camundongos , Camundongos EndogâmicosRESUMO
Intraperitoneal immunization of mice with a single dose (5 micrograms) of outer membrane proteins (OMP) of Shigella flexneri was found to evoke in the spleen the appearance of cells by means of which immunity to lethal dose of Shigella could be transferred into other mice. Active cells capable of transferring immunity appeared in the spleen of the animals as early as on day 3, reached the strongest protective activity on day 4 and disappeared on day 8 after immunization. Active cells from animals immunized with two doses of OMP maintained in the spleens for 19 days. The experiments revealed that immunity to Shigella could be transferred only with lymphocytes; macrophages were found to be inactive.
Assuntos
Proteínas da Membrana Bacteriana Externa/imunologia , Disenteria Bacilar/imunologia , Imunização Passiva , Linfócitos/imunologia , Shigella flexneri/imunologia , Animais , Camundongos , Camundongos Endogâmicos , Baço/imunologiaRESUMO
Wratizolin was found to inhibit completely or delay markedly the growth of fungi of Microsporum, Trichophyton and Epidermophyton genus. Mould fungi, yeasts, and yeast-like organisms, with a few exceptions, were not sensitive to Wratizolin.
