COVID-19 is caused by the SARS-CoV-2 virus and has spread globally in 2020. Cellular immunity may serve as an important functional marker of the disease, especially in the asymptomatic cases. Blood samples were collected from 46 convalescent donors with a history of COVID-19 and 38 control donors. Quantification of the T-cell response upon contact with SARS-CoV-2 proteins in vitro was based on IFN-γ. Significantly higher numbers of activated cells were measured in patients who underwent COVID-19. Anti-SARS-CoV-2 T cells were detected weeks after the active virus disappeared from the organism. Repeated sample collection after five months proved that the T-cell activation was weaker in time in 79 % of the patients. In the majority of cases, the CD4+ helper T-cell subpopulation was responsible for the immune reaction. Moreover, different viral proteins triggered activation in CD4+ helper and in CD8+ cytotoxic T cells. Together, these findings suggest that the T-cell activation level identifies the individuals who underwent COVID-19 and may become a diagnostic tool for the disease.

• MeSH
• aktivace lymfocytů MeSH
• COVID-19 * MeSH
• lidé MeSH
• protilátky virové MeSH
• SARS-CoV-2 MeSH
• T-lymfocyty MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

• Publikační typ
• abstrakt z konference MeSH

New approaches in regenerative medicine and vasculogenesis have generated a demand for sufficient numbers of human endothelial cells (ECs). ECs and their progenitors reside on the interior surface of blood and lymphatic vessels or circulate in peripheral blood; however, their numbers are limited, and they are difficult to expand after isolation. Recent advances in human induced pluripotent stem cell (hiPSC) research have opened possible avenues to generate unlimited numbers of ECs from easily accessible cell sources, such as the peripheral blood. In this study, we reprogrammed peripheral blood mononuclear cells, human umbilical vein endothelial cells (HUVECs), and human saphenous vein endothelial cells (HSVECs) into hiPSCs and differentiated them into ECs. The phenotype profiles, functionality, and genome stability of all hiPSC-derived ECs were assessed and compared with HUVECs and HSVECs. hiPSC-derived ECs resembled their natural EC counterparts, as shown by the expression of the endothelial surface markers CD31 and CD144 and the results of the functional analysis. Higher expression of endothelial progenitor markers CD34 and kinase insert domain receptor (KDR) was measured in hiPSC-derived ECs. An analysis of phosphorylated histone H2AX (γH2AX) foci revealed that an increased number of DNA double-strand breaks upon reprogramming into pluripotent cells. However, differentiation into ECs restored a normal number of γH2AX foci. Our hiPSCs retained a normal karyotype, with the exception of the HSVEC-derived hiPSC line, which displayed mosaicism due to a gain of chromosome 1. Peripheral blood from adult donors is a suitable source for the unlimited production of patient-specific ECs through the hiPSC interstage. hiPSC-derived ECs are fully functional and comparable to natural ECs. The protocol is eligible for clinical applications in regenerative medicine, if the genomic stability of the pluripotent cell stage is closely monitored.

• MeSH
• biologické markery metabolismus   MeSH
• buněčná diferenciace fyziologie   MeSH
• endoteliální buňky pupečníkové žíly (lidské) cytologie   metabolismus   MeSH
• endoteliální buňky cytologie   metabolismus   MeSH
• fibroblasty cytologie   metabolismus   MeSH
• fyziologická neovaskularizace fyziologie   MeSH
• indukované pluripotentní kmenové buňky cytologie   metabolismus   MeSH
• kultivované buňky MeSH
• leukocyty mononukleární cytologie   metabolismus   MeSH
• lidé MeSH
• regenerativní lékařství metody   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

BACKGROUND: Human induced pluripotent stem cells (hiPSCs) play roles in both disease modelling and regenerative medicine. It is critical that the genomic integrity of the cells remains intact and that the DNA repair systems are fully functional. In this article, we focused on the detection of DNA double-strand breaks (DSBs) by phosphorylated histone H2AX (known as γH2AX) and p53-binding protein 1 (53BP1) in three distinct lines of hiPSCs, their source cells, and one line of human embryonic stem cells (hESCs). METHODS: We measured spontaneously occurring DSBs throughout the process of fibroblast reprogramming and during long-term in vitro culturing. To assess the variations in the functionality of the DNA repair system among the samples, the number of DSBs induced by γ-irradiation and the decrease over time was analysed. The foci number was detected by fluorescence microscopy separately for the G1 and S/G2 cell cycle phases. RESULTS: We demonstrated that fibroblasts contained a low number of non-replication-related DSBs, while this number increased after reprogramming into hiPSCs and then decreased again after long-term in vitro passaging. The artificial induction of DSBs revealed that the repair mechanisms function well in the source cells and hiPSCs at low passages, but fail to recognize a substantial proportion of DSBs at high passages. CONCLUSIONS: Our observations suggest that cellular reprogramming increases the DSB number but that the repair mechanism functions well. However, after prolonged in vitro culturing of hiPSCs, the repair capacity decreases.

• MeSH
• 53BP1 genetika   metabolismus   MeSH
• buněčné linie MeSH
• DNA genetika   metabolismus   MeSH
• dvouřetězcové zlomy DNA * účinky záření   MeSH
• exprese genu MeSH
• fibroblasty cytologie   metabolismus   účinky záření   MeSH
• fosforylace účinky záření   MeSH
• histony genetika   metabolismus   MeSH
• indukované pluripotentní kmenové buňky cytologie   metabolismus   účinky záření   MeSH
• kontrolní body fáze G1 buněčného cyklu genetika   MeSH
• kontrolní body fáze G2 buněčného cyklu genetika   MeSH
• lidé MeSH
• lidské embryonální kmenové buňky cytologie   metabolismus   účinky záření   MeSH
• oprava DNA genetika   MeSH
• přeprogramování buněk MeSH
• stárnutí buněk genetika   účinky záření   MeSH
• záření gama MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Preclinical studies have demonstrated the promising potential of human induced pluripotent stem cells (hiPSCs) for clinical application. To fulfil this goal, efficient and safe methods to generate them must be established. Various reprogramming techniques were presented during seven years of hiPSCs research. Genome non-integrating and completely xeno-free protocols from the first biopsy to stable hiPSC clones are highly preferable in terms of future clinical application. In this short communication, we summarize the reprogramming experiments performed in our laboratories. We successfully generated hiPSCs using STEMCCA lentivirus, Sendai virus or episomal vectors. Human neonatal fibroblasts and CD34(+) blood progenitors were used as cell sources and were maintained either on mouse embryonic feeder cells or in feeder-free conditions. The reprogramming efficiency was comparable for all three methods and both cell types, while the best results were obtained in feeder-free conditions.

• MeSH
• antigeny CD34 metabolismus   MeSH
• biologické markery metabolismus   MeSH
• buněčné kultury metody   MeSH
• buněčné linie MeSH
• genom lidský genetika   MeSH
• imunohistochemie MeSH
• indukované pluripotentní kmenové buňky cytologie   metabolismus   MeSH
• lidé MeSH
• myši MeSH
• pluripotentní kmenové buňky cytologie   metabolismus   MeSH
• přeprogramování buněk genetika   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Transient, potent BCR-ABL inhibition with tyrosine kinase inhibitors (TKIs) was recently demonstrated to be sufficient to commit chronic myeloid leukemia (CML) cells to apoptosis irreversibly. This mechanism explains the clinical efficacy of once-daily dasatinib treatment, despite the rapid clearance of the drug from the plasma. However, our in vitro data suggest that apoptosis induction after transient TKI treatment, observed in the BCR-ABL-positive cell lines K562, KYO-1, and LAMA-84 and progenitor cells from chronic phase CML patients, is instead caused by a residual kinase inhibition that persists in the cells as a consequence of intracellular drug retention. High intracellular concentrations of imatinib and dasatinib residues were measured in transiently treated cells. Furthermore, the apoptosis induced by residual imatinib or dasatinib from transient treatment could be rescued by washing out the intracellularly retained drugs. The residual kinase inhibition was also undetectable by the phospho-CRKL assay. These findings confirm that continuous target inhibition is required for the optimal efficacy of kinase inhibitors.

• MeSH
• adaptorové proteiny signální transdukční metabolismus   MeSH
• apoptóza účinky léků   MeSH
• bcr-abl fúzní proteiny antagonisté a inhibitory   metabolismus   MeSH
• benzamidy metabolismus   farmakologie   MeSH
• biologický transport MeSH
• buňky kostní dřeně účinky léků   metabolismus   patologie   MeSH
• chronická fáze myeloidní leukemie farmakoterapie   metabolismus   patologie   MeSH
• chronická myeloidní leukemie farmakoterapie   enzymologie   metabolismus   MeSH
• fosforylace účinky léků   MeSH
• inhibitory proteinkinas metabolismus   farmakologie   MeSH
• jaderné proteiny metabolismus   MeSH
• kinetika MeSH
• lidé MeSH
• nádorové buněčné linie MeSH
• nádorové buňky kultivované MeSH
• nádorové kmenové buňky účinky léků   metabolismus   patologie   MeSH
• osmolární koncentrace MeSH
• piperaziny metabolismus   farmakologie   MeSH
• posttranslační úpravy proteinů účinky léků   MeSH
• protinádorové látky metabolismus   farmakologie   MeSH
• pyrimidiny metabolismus   farmakologie   MeSH
• thiazoly metabolismus   farmakologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

• Publikační typ
• abstrakty MeSH

This study combines mRNA and protein analysis using cDNA and antibody microarray techniques, respectively. These create a novel, integrated perspective into cellular molecular profiles. The aims of this study were to establish a reliable way of integrating these two approaches in order to obtain complex molecular profiles of the cell and to find suitable methods to normalize the data obtained using these approaches.

Antibody microarray and cDNA microarray techniques were used to study expression alterations in HL-60 cells that were differentiated into granulocytes using all-trans retinoic acid (ATRA). We selected this model to evaluate this combined profiling technique because the expression levels of most of the mRNA and protein species in these cells are not altered; therefore it is easier to track and define those species that are changed. The proteins whose levels were altered included c-myc, c-jun, Pyk2, FAK, PKC, TRF1, NF-kappaB and certain caspase types. These proteins are involved in apoptosis and hematopoietic differentiation pathways, and some have also been reported to have oncogenic potential. We compared the results obtained using the two methods, verified them by immunoblotting analysis, and devised normalization approaches.

This is one of the first demonstrations that a combination of antibody microarray and cDNA microarray techniques is required for complex molecular profiling of cells based on multiple parameters. This approach allows a more detailed molecular phenotype of the given sample to be obtained. The results obtained using a combination of the two profiling methods are consistent with those from previous studies that used more traditional methods.

• MeSH
• čipová analýza proteinů MeSH
• financování organizované MeSH
• fokální adhezní kinasa 2 analýza   MeSH
• geny myc MeSH
• HL-60 buňky MeSH
• lidé MeSH
• messenger RNA analýza   MeSH
• protein TRF1 analýza   MeSH
• sekvenční analýza hybridizací s uspořádaným souborem oligonukleotidů MeSH
• tretinoin farmakologie   MeSH
• Check Tag
• lidé MeSH