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1.
Int J Mol Sci ; 25(2)2024 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-38256102

RESUMO

Atherosclerotic plaques are sites of chronic inflammation with diverse cell contents and complex immune signaling. Plaque progression and destabilization are driven by the infiltration of immune cells and the cytokines that mediate their interactions. Here, we attempted to compare the systemic cytokine profiles in the blood plasma of patients with atherosclerosis and the local cytokine production, using ex vivo plaque explants from the same patients. The developed method of 41-plex xMAP data normalization allowed us to differentiate twenty-two cytokines produced by the plaque that were not readily detectable in free circulation and six cytokines elevated in blood plasma that may have other sources than atherosclerotic plaque. To verify the xMAP data on the putative atherogenesis-driving chemokines MCP-1 (CCL2), MIP-1α (CCL3), MIP-1ß (CCL4), RANTES (CCL5), and fractalkine (CX3CL1), qPCR was performed. The MIP1A (CCL3), MIP1B (CCL4), FKN (CX3CL1), and MCP1 (CCL2) genes were expressed at high levels in the plaques, whereas RANTES (CCL5) was almost absent. The expression patterns of the chemokines were restricted to the plaque cell types: the MCP1 (CCL2) gene was predominantly expressed in endothelial cells and monocytes/macrophages, MIP1A (CCL3) in monocytes/macrophages, and MIP1B (CCL4) in monocytes/macrophages and T cells. RANTES (CCL5) was restricted to T cells, while FKN (CX3CL1) was not differentially expressed. Taken together, our data indicate a plaque-specific cytokine production profile that may be a useful tool in atherosclerosis studies.


Assuntos
Aterosclerose , Endarterectomia das Carótidas , Placa Aterosclerótica , Humanos , Placa Aterosclerótica/cirurgia , Células Endoteliais , Citocinas , Plasma
2.
Int J Mol Sci ; 25(3)2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38338779

RESUMO

The development of drugs for the treatment of acute kidney injury (AKI) that could suppress the excessive inflammatory response in damaged kidneys is an important clinical challenge. Recently, synaptamide (N-docosahexaenoylethanolamine) has been shown to exert anti-inflammatory and neurogenic properties. The aim of this study was to investigate the anti-inflammatory effect of synaptamide in ischemic AKI. For this purpose, we analyzed the expression of inflammatory mediators and the infiltration of different leukocyte populations into the kidney after injury, evaluated the expression of the putative synaptamide receptor G-protein-coupled receptor 110 (GPR110), and isolated a population of CD11b/c+ cells mainly representing neutrophils and macrophages using cell sorting. We also evaluated the severity of AKI during synaptamide therapy and the serum metabolic profile. We demonstrated that synaptamide reduced the level of pro-inflammatory interleukins and the expression of integrin CD11a in kidney tissue after injury. We found that the administration of synaptamide increased the expression of its receptor GPR110 in both total kidney tissue and renal CD11b/c+ cells that was associated with the reduced production of pro-inflammatory interleukins in these cells. Thus, we demonstrated that synaptamide therapy mitigates the inflammatory response in kidney tissue during ischemic AKI, which can be achieved through GPR110 signaling in neutrophils and a reduction in these cells' pro-inflammatory interleukin production.


Assuntos
Injúria Renal Aguda , Etanolaminas , Receptores Acoplados a Proteínas G , Traumatismo por Reperfusão , Animais , Ratos , Injúria Renal Aguda/tratamento farmacológico , Injúria Renal Aguda/metabolismo , Anti-Inflamatórios/metabolismo , Interleucinas/metabolismo , Rim/metabolismo , Receptores Acoplados a Proteínas G/efeitos dos fármacos , Receptores Acoplados a Proteínas G/metabolismo , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo
3.
J Virol ; 96(1): e0150521, 2022 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-34613791

RESUMO

During evolution, viruses had to adapt to an increasingly complex environment of eukaryotic cells. Viral proteins that need to enter the cell nucleus or associate with nucleoli possess nuclear localization signals (NLSs) and nucleolar localization signals (NoLSs) for nuclear and nucleolar accumulation, respectively. As viral proteins are relatively small, acquisition of novel sequences seems to be a more complicated task for viruses than for eukaryotes. Here, we carried out a comprehensive analysis of the basic domain (BD) of HIV-1 Tat to show how viral proteins might evolve with NLSs and NoLSs without an increase in protein size. The HIV-1 Tat BD is involved in several functions, the most important being the transactivation of viral transcription. The BD also functions as an NLS, although it is substantially longer than a typical NLS. It seems that different regions in the BD could function as NLSs due to its enrichment with positively charged amino acids. Additionally, the high positive net charge inevitably causes the BD to function as an NoLS through a charge-specific mechanism. The integration of NLSs and NoLSs into functional domains enriched with positively charged amino acids might be a mechanism that allows the condensation of different functional sequences in small protein regions and, as a result, reduces protein size, influencing the origin and evolution of NLSs and NoLSs in viruses. IMPORTANCE Here, we investigated the molecular mechanism of nuclear localization signal (NLS) and nucleolar localization signal (NoLS) integration into the basic domain of HIV-1 Tat (49RKKRRQRRR57) and found that these two supplementary functions (i.e., function of NLS and function of NoLS) are embedded in the basic domain amino acid sequence. The integration of NLSs and NoLSs into functional domains of viral proteins enriched with positively charged amino acids is a mechanism that allows the concentration of different functions within small protein regions. Integration of NLS and NoLS into functional protein domains might have influenced the viral evolution, as this could prevent an increase in the protein size.


Assuntos
Regulação Viral da Expressão Gênica , Infecções por HIV/virologia , HIV-1/fisiologia , Sinais de Localização Nuclear , Domínios e Motivos de Interação entre Proteínas , Produtos do Gene tat do Vírus da Imunodeficiência Humana/química , Produtos do Gene tat do Vírus da Imunodeficiência Humana/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Nucléolo Celular/metabolismo , Núcleo Celular/metabolismo , Sequência Consenso , Evolução Molecular , Interações Hospedeiro-Patógeno , Modelos Moleculares , Ligação Proteica , Transporte Proteico , Relação Estrutura-Atividade , Proteínas Virais/metabolismo , Produtos do Gene tat do Vírus da Imunodeficiência Humana/genética
4.
Ultrastruct Pathol ; 47(5): 382-387, 2023 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-37306223

RESUMO

Recent studies indicate that cilia impairment, accompanied by the axonema loss and the basal body misorientation, is a common pathological feature of SARS-CoV-2-infected bronchial epithelial cells. However, these data were obtained using either cultured cells, or animal models, while in human postmortem material, cilia impairment has not been described yet. Here, we present direct observation of cilia impairment in SARS-CoV-2-infected bronchial epithelial cells using transmission electron microscopy of the autopsy material. We were able to observe only single infected cells with cilia impairment in one of twelve examined specimens, while the large number of desquamated bronchial epithelial cells with undisturbed ciliary layer was visible in the bronchial lumens. Thus, it seems that in the lungs of infected patients, the majority of bronchial cells do not die as a direct result of infection, which may explain the rarity of this finding in the autopsy material.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Humanos , Cílios , Autopsia , COVID-19/patologia , Células Epiteliais
5.
Clin Infect Dis ; 75(1): e1-e9, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-35435222

RESUMO

BACKGROUND: During the ongoing coronavirus disease 2019 (COVID-19) pandemic, many individuals were infected with and have cleared the virus, developing virus-specific antibodies and effector/memory T cells. An important unanswered question is what levels of T-cell and antibody responses are sufficient to protect from the infection. METHODS: In 5340 Moscow residents, we evaluated anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immunoglobulin M (IgM)/immunoglobulin G (IgG) titers and frequencies of the T cells specific to the membrane, nucleocapsid, and spike proteins of SARS-CoV-2, using interferon gamma (IFN-γ) enzyme-linked immunosorbent spot (ELISpot) assay. Additionally, we evaluated the fractions of virus-specific CD4+ and CD8+ T cells using intracellular staining of IFN-γ and interleukin 2 followed by flow cytometry. We analyzed the COVID-19 rates as a function of the assessed antibody and T-cell responses, using the Kaplan-Meier estimator method, for up to 300 days postinclusion. RESULTS: We showed that T-cell and antibody responses are closely interconnected and are commonly induced concurrently. Magnitudes of both responses inversely correlated with infection probability. Individuals positive for both responses demonstrated the highest levels of protectivity against the SARS-CoV-2 infection. A comparable level of protection was found in individuals with antibody response only, whereas the T-cell response by itself granted only intermediate protection. CONCLUSIONS: We found that the contribution of the virus-specific antibodies to protection against SARS-CoV-2 infection is more pronounced than that of the T cells. The data on the virus-specific IgG titers may be instructive for making decisions in personalized healthcare and public anti-COVID-19 policies. Clinical Trials Registration. NCT04898140.


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Antivirais , Humanos , Imunoglobulina G , Estudos Prospectivos
6.
Eur J Immunol ; 51(7): 1857-1859, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33772780

RESUMO

T-cell accumulation in atherosclerotic plaques contributes to plaque destabilization. We found that several chemokine receptors are differentially expressed on peripheral blood compared to plaque-resident T cells and corresponding ligands are upregulated in plaques. These data indicate that T-cell migration into human atherosclerotic plaques may predominantly occur via CCR5-CCL3 and CX3CR1-CX3CL1 interactions.


Assuntos
Receptor 1 de Quimiocina CX3C/metabolismo , Movimento Celular/fisiologia , Quimiocina CCL3/metabolismo , Quimiocina CX3CL1/metabolismo , Placa Aterosclerótica/metabolismo , Receptores CCR5/metabolismo , Linfócitos T/metabolismo , Aterosclerose/metabolismo , Células Cultivadas , Humanos
7.
PLoS Pathog ; 16(9): e1008885, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32976527

RESUMO

Atherosclerotic cardiovascular disease (ASCVD) remains an important cause of morbidity in the general population and risk for ASCVD is increased approximately 2-fold in persons living with HIV infection (PLWH). This risk is linked to elevated CD8 T cell counts that are abundant in atherosclerotic plaques and have been implicated in disease pathogenesis yet the mechanisms driving T cell recruitment to and activation within plaques are poorly defined. Here we investigated the role of CD8 T cells in atherosclerosis in a non-human primate model of HIV infection and in the HIV-uninfected elderly; we sought to identify factors that promote the activation, function, and recruitment to endothelium of CX3CR1+ CD8 T cells. We measured elevated expression of CX3CL1 and IL-15, and increased CD8 T cell numbers in the aortas of rhesus macaques infected with SIV or SHIV, and demonstrated similar findings in atherosclerotic vessels of HIV-uninfected humans. We found that recombinant TNF enhanced the production and release of CX3CL1 and bioactive IL-15 from aortic endothelial cells, but not from aortic smooth muscle cells. IL-15 in turn promoted CX3CR1 surface expression on and TNF synthesis by CD8 T cells, and IL-15-treated CD8 T cells exhibited enhanced CX3CL1-dependent chemoattraction toward endothelial cells in vitro. Finally, we show that CD8 T cells in human atherosclerotic plaques have an activated, resident phenotype consistent with in vivo IL-15 and CX3CL1 exposure. In this report, we define a novel model of CD8 T cell involvement in atherosclerosis whereby CX3CL1 and IL-15 operate in tandem within the vascular endothelium to promote infiltration by activated CX3CR1+ memory CD8 T cells that drive further endothelial activation via TNF. We propose that these interactions are prevalent in aging and in PLWH, populations where circulating activated CX3CR1+ CD8 T cell numbers are often expanded.


Assuntos
Aterosclerose/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Quimiocina CX3CL1/metabolismo , Infecções por HIV/metabolismo , Interleucina-15/metabolismo , Idoso , Animais , Células Endoteliais/metabolismo , Humanos , Macaca mulatta/metabolismo , Receptores de Quimiocinas/metabolismo
8.
J Immunol ; 204(10): 2722-2733, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32229536

RESUMO

Cytotoxic CD4 T cells are linked to cardiovascular morbidities and accumulate in both HIV and CMV infections, both of which are associated with increased risk of cardiovascular disease (CVD). In this study, we identify CMV coinfection as a major driver of the cytotoxic phenotype, characterized by elevated CD57 expression and reduced CD28 expression, in circulating CD4 T cells from people living with HIV infection, and investigate potential mechanisms linking this cell population to CVD. We find that human CD57+ CD4 T cells express high levels of the costimulatory receptor CD2 and that CD2/LFA-3 costimulation results in a more robust and polyfunctional effector response to TCR signals, compared with CD28-mediated costimulation. CD57+ CD4 T cells also express the vascular endothelium-homing receptor CX3CR1 and migrate toward CX3CL1-expressing endothelial cells in vitro. IL-15 promotes the cytotoxic phenotype, elevates CX3CR1 expression, and enhances the trafficking of CD57+ CD4 T cells to endothelium and may therefore be important in linking these cells to cardiovascular complications. Finally, we demonstrate the presence of activated CD57+ CD4 T cells and expression of CX3CL1 and LFA-3 in atherosclerotic plaque tissues from HIV-uninfected donors. Our findings are consistent with a model in which cytotoxic CD4 T cells contribute to CVD in HIV/CMV coinfection and in atherosclerosis via CX3CR1-mediated trafficking and CD2/LFA-3-mediated costimulation. This study identifies several targets for therapeutic interventions and may help bridge the gap in understanding how CMV infection and immunity are linked to increased cardiovascular risk in people living with HIV infection.


Assuntos
Vasos Sanguíneos/fisiologia , Linfócitos T CD4-Positivos/imunologia , Infecções por Citomegalovirus/imunologia , Citomegalovirus/fisiologia , Infecções por HIV/imunologia , HIV-1/fisiologia , Placa Aterosclerótica/imunologia , Antígenos CD28/metabolismo , Antígenos CD57/metabolismo , Antígenos CD58/metabolismo , Receptor 1 de Quimiocina CX3C/metabolismo , Movimento Celular , Quimiocina CX3CL1/metabolismo , Coinfecção , Citotoxicidade Imunológica , Humanos , Receptores CXCR3/metabolismo , Risco
9.
Int J Mol Sci ; 24(1)2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36613860

RESUMO

The clinical course of the new coronavirus disease 2019 (COVID-19) has shown that patients with chronic lymphocytic leukemia (CLL) are characterized by a high mortality rate, poor response to standard treatment, and low virus-specific antibody response after recovery and/or vaccination. To date, there are no data on the safety and efficacy of the combined vector vaccine Sputnik V in patients with CLL. Here, we analyzed and compared the magnitudes of the antibody and T cell responses after vaccination with the Sputnik V vaccine among healthy donors and individuals with CLL with different statuses of preexposure to coronavirus. We found that vaccination of the COVID-19-recovered individuals resulted in the boosting of pre-existing immune responses in both healthy donors and CLL patients. However, the COVID-19-naïve CLL patients demonstrated a considerably lower antibody response than the healthy donors, although they developed a robust T cell response. Regardless of the previous infection, the individuals over 70 years old demonstrated a decreased response to vaccination, as did those receiving anti-CD20 therapy. In summary, we showed that Sputnik V, like other vaccines, did not induce a robust antibody response in individuals with CLL; however, it provided for the development of a significant anti-COVID-19 T cell response.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Leucemia Linfocítica Crônica de Células B , Idoso , Humanos , Anticorpos Antivirais , COVID-19/prevenção & controle , Linfócitos T , Vacinação , Vacinas Combinadas , Vacinas contra COVID-19/imunologia , Vacinas Sintéticas
10.
Int J Mol Sci ; 23(17)2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36077272

RESUMO

CD133 is an extensively studied marker of the most malignant tumor cell population, designated as cancer stem cells (CSCs). However, the function of this glycoprotein and its involvement in cell regulatory cascades are still poorly understood. Here we show a positive correlation between the level of CD133 plasma membrane expression and the proliferative activity of cells of the Caco-2, HT-29, and HUH7 cancer cell lines. Despite a substantial difference in the proliferative activities of cell populations with different levels of CD133 expression, transcriptomic and proteomic profiling revealed only minor distinctions between them. Nonetheless, a further in silico assessment of the differentially expressed transcripts and proteins revealed 16 proteins that could be involved in the regulation of CD133 expression; these were assigned ranks reflecting the apparent extent of their involvement. Among them, the TRIM28 transcription factor had the highest rank. The prominent role of TRIM28 in CD133 expression modulation was confirmed experimentally in the Caco2 cell line clones: the knockout, though not the knockdown, of the TRIM28 gene downregulated CD133. These results for the first time highlight an important role of the TRIM28 transcription factor in the regulation of CD133-associated cancer cell heterogeneity.


Assuntos
Antígeno AC133/genética , Células-Tronco Neoplásicas/citologia , Proteína 28 com Motivo Tripartido/metabolismo , Antígeno AC133/metabolismo , Células CACO-2 , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias/metabolismo , Células-Tronco Neoplásicas/metabolismo , Fenótipo , Proteômica , Fatores de Transcrição/metabolismo
11.
Biol Cell ; 111(10): 245-261, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31403697

RESUMO

BACKGROUND INFORMATION: Metastatic disease is caused by the ability of cancer cells to reach distant organs and form secondary lesions at new locations. Dissemination of cancer cells depends on their migration plasticity - an ability to switch between motility modes driven by distinct molecular machineries. One of such switches is mesenchymal-to-amoeboid transition. Although mesenchymal migration of individual cells requires Arp2/3-dependent actin polymerisation, amoeboid migration is characterised by a high level of actomyosin contractility and often involves the formation of membrane blebs. The acquisition of amoeboid motility by mesenchymal cells is often associated with enhanced metastasis. RESULTS: We studied the ability of mesenchymal HT1080 fibrosarcoma cells to switch to amoeboid motility. We induced the transition from lamellipodium-rich to blebbing phenotype either by down-regulating the Arp2/3 complex, pharmacologically or by RNAi, or by decreasing substrate adhesiveness. Each of these treatments induced blebbing in a subset of fibrosarcoma cells, but not in normal subcutaneous fibroblasts. A significant fraction of HT1080 cells that switched to blebbing behaviour exhibited stem cell-like features, such as expression of the stem cell marker CD133, an increased efflux of Hoechst-33342 and positive staining for Oct4, Sox2 and Nanog. Furthermore, the isolated CD133+ cells demonstrated an increased ability to switch to bleb-rich amoeboid phenotype both under inhibitor's treatment and in 3D collagen gels. CONCLUSIONS: Together, our data show a significant correlation between the increased ability of cells to switch between migration modes and their stem-like features, suggesting that migration plasticity is an additional property of stem-like population of fibrosarcoma cells. This combination of features could facilitate both dissemination of these cells to distant locations, and their establishment self-renewal in a new microenvironment, as required for metastasis formation. SIGNIFICANCE: These data suggest that migration plasticity is a new feature of cancer stem-like cells that can significantly facilitate their dissemination to a secondary location by allowing them to adapt quickly to challenging microenvironments. Moreover, it complements their resistance to apoptosis and self-renewal potential, thus enabling them not only to disseminate efficiently, but also to survive and colonise new niches.


Assuntos
Movimento Celular , Fibrossarcoma/patologia , Células-Tronco Neoplásicas/patologia , Antígeno AC133/metabolismo , Citoesqueleto de Actina/metabolismo , Complexo 2-3 de Proteínas Relacionadas à Actina/metabolismo , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal , Humanos , Microambiente Tumoral
12.
J Cell Biochem ; 120(3): 4472-4484, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30260032

RESUMO

Enhanced glucose uptake by cancer cells was demonstrated in many studies in vitro and in vivo. Glycolysis is one of the main ways of obtaining energy in hypoxia conditions. However, in addition to energy exchange, carbohydrates are also necessary for the posttranslational modification of the protein molecules. Cancer cells are often characterized by an enhanced expression of different glycoproteides. Correct glycosylation defines the structure and activity of such molecules. We demonstrated that under the same cultivation conditions, the intensity of glycosylation does not depend on the total number of potential O-glycosylation sites in one molecule. As a model for the investigation, the tandem repeat region (region with variable number of tandem repeats) of the human mucin MUC1, in which each of the repeats carries four potential O-glycosylation sites, was used. An increase of the tandem repeat number in the recombinant protein did not lead to a proportional increase in the level of sLea glycosides. A consequence of this was a reduction in the number of recombinant proteins associated with the cytoplasmic membrane at an overall high expression level. Prolongation of the cultivation duration led to a reduction in the expression level of the recombinant proteins by up to 30% of the initial level, and the intensity of this reduction was in a direct ratio to the number of tandem repeats in the protein molecule.


Assuntos
Regulação para Baixo , Mucina-1 , Sequências Repetitivas de Aminoácidos , Linhagem Celular , Glicosilação , Humanos , Mucina-1/biossíntese , Mucina-1/genética
13.
J Cell Sci ; 129(24): 4509-4520, 2016 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-27875271

RESUMO

Nuclear bodies are membraneless organelles that play important roles in genome functioning. A specific type of nuclear bodies known as interphase prenucleolar bodies (iPNBs) are formed in the nucleoplasm after hypotonic stress from partially disassembled nucleoli. iPNBs are then disassembled, and the nucleoli are reformed simultaneously. Here, we show that diffusion of B23 molecules (also known as nucleophosmin, NPM1) from iPNBs, but not fusion of iPNBs with the nucleoli, contributes to the transfer of B23 from iPNBs to the nucleoli. Maturation of pre-ribosomal RNAs (rRNAs) and the subsequent outflow of mature rRNAs from iPNBs led to the disassembly of iPNBs. We found that B23 transfer was dependent on the synthesis of pre-rRNA molecules in nucleoli; these pre-rRNA molecules interacted with B23 and led to its accumulation within nucleoli. The transfer of B23 between iPNBs and nucleoli was accomplished through a nucleoplasmic pool of B23, and increased nucleoplasmic B23 content retarded disassembly, whereas B23 depletion accelerated disassembly. Our results suggest that iPNB disassembly and nucleolus assembly might be coupled through RNA-dependent exchange of nucleolar proteins, creating a highly dynamic system with long-distance correlations between spatially distinct processes.


Assuntos
Corpos de Inclusão Intranuclear/metabolismo , RNA/metabolismo , Trifosfato de Adenosina/metabolismo , Nucléolo Celular/metabolismo , Difusão , Células HeLa , Humanos , Interfase , Nucleofosmina , Processamento Pós-Transcricional do RNA , Estresse Fisiológico
14.
Biochim Biophys Acta ; 1853(1): 101-10, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25315210

RESUMO

The majority of known nucleolar proteins are freely exchanged between the nucleolus and the surrounding nucleoplasm. One way proteins are retained in the nucleoli is by the presence of specific amino acid sequences, namely nucleolar localization signals (NoLSs). The mechanism by which NoLSs retain proteins inside the nucleoli is still unclear. Here, we present data showing that the charge-dependent (electrostatic) interactions of NoLSs with nucleolar components lead to nucleolar accumulation as follows: (i) known NoLSs are enriched in positively charged amino acids, but the NoLS structure is highly heterogeneous, and it is not possible to identify a consensus sequence for this type of signal; (ii) in two analyzed proteins (NF-κB-inducing kinase and HIV-1 Tat), the NoLS corresponds to a region that is enriched for positively charged amino acid residues; substituting charged amino acids with non-charged ones reduced the nucleolar accumulation in proportion to the charge reduction, and nucleolar accumulation efficiency was strongly correlated with the predicted charge of the tested sequences; and (iii) sequences containing only lysine or arginine residues (which were referred to as imitative NoLSs, or iNoLSs) are accumulated in the nucleoli in a charge-dependent manner. The results of experiments with iNoLSs suggested that charge-dependent accumulation inside the nucleoli was dependent on interactions with nucleolar RNAs. The results of this work are consistent with the hypothesis that nucleolar protein accumulation by NoLSs can be determined by the electrostatic interaction of positively charged regions with nucleolar RNAs rather than by any sequence-specific mechanism.


Assuntos
Nucléolo Celular/metabolismo , Proteínas Nucleares/metabolismo , Sequência de Aminoácidos , Proteínas de Fluorescência Verde/metabolismo , Células HeLa , Humanos , Dados de Sequência Molecular , Sinais de Localização Nuclear
15.
J Virol ; 89(20): 10591-601, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26269177

RESUMO

UNLABELLED: Cell-to-cell transmission is an efficient mechanism to disseminate human immunodeficiency virus type 1 (HIV-1) and human T cell lymphotropic virus type 1 (HTLV-1). However, it has been challenging to quantify the level of cell-to-cell transmission because the virus-producing cells cannot be easily distinguished from infected target cells. We have previously described replication-dependent vectors that can quantify infection events in cocultured cells. These vectors contain an antisense-oriented promoter and reporter gene interrupted by a sense-oriented intron from the human gamma-globin gene. This strategy prevents expression of the reporter gene in the transfected cells but permits its expression in target cells after infection. However, the gamma-globin intron is not efficiently removed by splicing in the aforementioned vectors, thereby reducing the level of reporter gene expression after transduction into target cells. Here, we used two approaches to improve the replication-dependent vectors. First, we improved the splicing events that remove the gamma-globin intron by optimizing the intron insertion site within the reporter gene. Second, we improved the packaging of the spliced RNA without the gamma-globin intron by targeting the intron-containing RNA via microRNA 30 (miR30)-based short hairpin RNAs. Using two optimized fluorescent reporter vectors and flow cytometry, we determined that multiply HIV-1-infected cells were generated at a higher frequency in coculture than in cell-free infection; furthermore, this increase was dependent upon viruses bearing HIV-1 Env. Compared with previously described vectors, these improved vectors can quantify the infection in lymphocytes and in primary cells with a higher sensitivity and allow the detection and quantitation of multiply infected cells, providing better tools to study retroviral cell-mediated infection. IMPORTANCE: The human-pathogenic retroviruses HTLV-1 and HIV-1 can be transmitted more efficiently in vivo via direct contact of infected cells with healthy target cells than through cell-free virion-mediated infection. Despite its importance, cell-to-cell transmission has been difficult to quantify because the previously infected cells and the newly infected cells are mixed together in the same culture. In the current study, we generated vectors that are significantly improved over the previously described replication-dependent vectors. As a result, these improved vectors can efficiently detect and quantify cell-to-cell transmission or new infection events in cells in mixed culture. These luciferase- or fluorescence protein-based reporter vectors can be used to quantify and study HIV-1 or HTLV-1 cell-mediated infection in a simple one-step transfection/infection assay.


Assuntos
Linfócitos T CD4-Positivos/virologia , Genes Reporter , Vetores Genéticos/química , HIV-1/genética , Vírus Linfotrópico T Tipo 1 Humano/genética , RNA Interferente Pequeno/genética , Replicação Viral/genética , Bioensaio , Linfócitos T CD4-Positivos/metabolismo , Linhagem Celular , Engenharia Genética , Vetores Genéticos/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , HIV-1/metabolismo , Vírus Linfotrópico T Tipo 1 Humano/metabolismo , Humanos , Íntrons , Luciferases/genética , Luciferases/metabolismo , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Splicing de RNA , RNA Interferente Pequeno/metabolismo , Transfecção , Vírion/genética , Vírion/metabolismo , gama-Globinas/genética , gama-Globinas/metabolismo , Proteína Vermelha Fluorescente
16.
Biochim Biophys Acta ; 1836(1): 105-22, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23481260

RESUMO

Increasing evidence of intratumor heterogeneity and its augmentation due to selective pressure of microenvironment and recent achievements in cancer therapeutics lead to the need to investigate and track the tumor subclonal structure. Cell sorting of heterogeneous subpopulations of tumor and tumor-associated cells has been a long established strategy in cancer research. Advancement in lasers, computer technology and optics has led to a new generation of flow cytometers and cell sorters capable of high-speed processing of single cell suspensions. Over the last several years cell sorting was used in combination with molecular biological methods, imaging and proteomics to characterize primary and metastatic cancer cell populations, minimal residual disease and single tumor cells. It was the principal method for identification and characterization of cancer stem cells. Analysis of single cancer cells may improve early detection of tumors, monitoring of circulating tumor cells, evaluation of intratumor heterogeneity and chemotherapeutic treatments. The aim of this review is to provide an overview of major cell sorting applications and approaches with new prospective developments such as microfluidics and microchip technologies.


Assuntos
Biomarcadores Tumorais , Pesquisa Biomédica , Separação Celular/métodos , Heterogeneidade Genética , Neoplasias/patologia , Animais , Citometria de Fluxo , Humanos , Análise em Microsséries , Neoplasias/terapia
17.
Nat Commun ; 15(1): 4455, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38796479

RESUMO

Lipids are the most abundant but poorly explored components of the human brain. Here, we present a lipidome map of the human brain comprising 75 regions, including 52 neocortical ones. The lipidome composition varies greatly among the brain regions, affecting 93% of the 419 analyzed lipids. These differences reflect the brain's structural characteristics, such as myelin content (345 lipids) and cell type composition (353 lipids), but also functional traits: functional connectivity (76 lipids) and information processing hierarchy (60 lipids). Combining lipid composition and mRNA expression data further enhances functional connectivity association. Biochemically, lipids linked with structural and functional brain features display distinct lipid class distribution, unsaturation extent, and prevalence of omega-3 and omega-6 fatty acid residues. We verified our conclusions by parallel analysis of three adult macaque brains, targeted analysis of 216 lipids, mass spectrometry imaging, and lipidome assessment of sorted murine neurons.


Assuntos
Encéfalo , Lipidômica , Lipídeos , Humanos , Animais , Encéfalo/metabolismo , Camundongos , Adulto , Lipídeos/química , Lipídeos/análise , Masculino , Metabolismo dos Lipídeos , Macaca , Neurônios/metabolismo , Feminino , Ácidos Graxos Ômega-3/metabolismo , Ácidos Graxos Ômega-6/metabolismo , Bainha de Mielina/metabolismo , Pessoa de Meia-Idade
18.
bioRxiv ; 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-36789445

RESUMO

Lung inflammation, pneumonia, is an acute respiratory disease of varying etiology that has recently drawn much attention during the COVID-19 pandemic as lungs are among the main targets for SARS-CoV-2. Multiple other etiological agents are associated with pneumonias. Here, we describe a newly-recognized pathology, namely abnormal lipid depositions in the lungs of patients who died from COVID-19 as well as from non-COVID-19 pneumonias. Our analysis of both semi-thin and Sudan III-stained lung specimens revealed extracellular and intracellular lipid depositions irrespective of the pneumonia etiology. Most notably, lipid depositions were located within vessels adjacent to inflamed regions, where they apparently interfere with the blood flow. Structurally, the lipid droplets in the inflamed lung tissue were homogeneous and lacked outer membranes as assessed by electron microscopy. Morphometric analysis of lipid droplet deposition area allowed us to distinguish the non-pneumonia control lung specimens from the macroscopically intact area of the pneumonia lung and from the inflamed area of the pneumonia lung. Our measurements revealed a gradient of lipid deposition towards the inflamed region. The pattern of lipid distribution proved universal for all pneumonias. Finally, lipid metabolism in the lung tissue was assessed by the fatty acid analysis and by expression of genes involved in lipid turnover. Chromato-mass spectrometry revealed that unsaturated fatty acid content was elevated at inflammation sites compared to that in control non-inflamed lung tissue from the same individual. The expression of genes involved in lipid metabolism was altered in pneumonia, as shown by qPCR and in silico RNA-seq analysis. Thus, pneumonias of various etiologies are associated with specific lipid abnormalities; therefore, lipid metabolism can be considered to be a target for new therapeutic strategies.

19.
Front Med (Lausanne) ; 9: 891916, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35911408

RESUMO

Atherosclerosis is the major cause of cardiovascular disease that is characterized by plaque formation in the blood vessel wall. Atherosclerotic plaques represent sites of chronic inflammation with diverse cell content that is shifted toward the prevalence of cytotoxic T-lymphocytes (CTLs) upon plaque progression. The studies of CTL recruitment to atherosclerotic plaques require adequate in vitro models accounting for CTL interactions with chemokine-ligands and extracellular matrix fibers via surface chemokine receptors and integrins. Here we applied such a model by investigating CTL adhesion and migration on six types of coated surfaces. We assessed adhesion and motility metrics, the expression of chemokine receptors, and integrins in CTLs of patients with atherosclerosis and healthy donors. Using fibronectin, platelet-poor plasma from patients with atherosclerosis, and conditioned medium from atherosclerotic plaques we revealed the role of substrate in CTL adhesiveness: fibronectin alone and fibronectin combined with platelet-poor plasma and conditioned medium elevated the CTL adhesiveness - in patients the elevation was significantly higher than in healthy donors (p = 0.02, mixed 2-way ANOVA model). This was in line with our finding that the expression levels of integrin-coding mRNAs were elevated in the presence of fibronectin (p < 0.05) and ITGB1, ITGA1, and ITGA4 were specifically upregulated in patients compared to healthy donors (p < 0.01). Our experimental model did not affect the expression levels of mRNAs CCR4, CCR5, and CX3CR1 coding the chemokine receptors that drive T-lymphocyte migration to plaques. Thus, we demonstrated the substrate-dependence of integrin expression and discriminated CTLs from patients and healthy donors by adhesion parameters and integrin expression levels.

20.
Eur J Cell Biol ; 101(3): 151246, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35667338

RESUMO

The tight interaction between somatic and germline cells is conserved in animal spermatogenesis. The testes of Drosophila melanogaster are the model of choice to identify processes responsible for mature gamete production. However, processes of differentiation and soma-germline interactions occurring in somatic cyst cells are currently understudied. Here we focused on the comparison of transcriptome expression patterns of early and mature somatic cyst cells to find out the developmental changes taking place in them. We employed a FACS-based approach for the isolation of early and mature somatic cyst cells from fly testes, subsequent preparation of RNA-Seq libraries, and analysis of gene differential expression in the sorted cells. We found increased expression of genes involved in cell cycle-related processes in early cyst cells, which is necessary for the proliferation and self-renewal of a crucial population of early cyst cells, cyst stem cells. Genes proposedly required for lamellipodium-like projection organization for proper cyst formation were also detected among the upregulated ones in early cyst cells. Gene Ontology and interactome analyses of upregulated genes in mature cyst cells revealed a striking over-representation of gene categories responsible for metabolic and catabolic cellular processes, as well as genes supporting the energetic state of the cells provided by oxidative phosphorylation that is carried out in mitochondria. Our comparative analyses of differentially expressed genes revealed major peculiarities in early and mature cyst cells and provide novel insight into their regulation, which is important for male fertility.


Assuntos
Cistos , Proteínas de Drosophila , Animais , Drosophila/metabolismo , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Masculino , Espermatogênese , Testículo/metabolismo
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