Since the publication of the first chicken genome sequence, we have encountered genes playing key roles in mammalian immunology, but being seemingly absent in birds. One of those was, until recently, Foxp3, the master transcription factor of regulatory T cells in mammals. Therefore, avian regulatory T cell research is still poorly standardized. In this study we identify a chicken ortholog of Foxp3 We prove sequence homology with known mammalian and sauropsid sequences, but also reveal differences in major domains. Expression profiling shows an association of Foxp3 and CD25 expression levels in CD4+CD25+ peripheral T cells and identifies a CD4-CD25+Foxp3high subset of thymic lymphocytes that likely represents yet undescribed avian regulatory T precursor cells. We conclude that Foxp3 is existent in chickens and that it shares certain functional characteristics with its mammalian ortholog. Nevertheless, pathways for regulatory T cell development and Foxp3 function are likely to differ between mammals and birds. The identification and characterization of chicken Foxp3 will help to define avian regulatory T cells and to analyze their functional properties and thereby advance the field of avian immunology.

• MeSH
• aktivace lymfocytů imunologie   MeSH
• buněčná diferenciace imunologie   MeSH
• forkhead transkripční faktory genetika   MeSH
• genom genetika   MeSH
• kur domácí genetika   imunologie   MeSH
• receptor interleukinu-2 - alfa-podjednotka metabolismus   MeSH
• regulační T-lymfocyty imunologie   MeSH
• sekvence aminokyselin genetika   MeSH
• sekvence nukleotidů MeSH
• sekvenční analýza DNA MeSH
• sekvenční homologie MeSH
• sekvenční seřazení MeSH
• stanovení celkové genové exprese MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

A precisely balanced activity of canonical Wnt signaling is essential for a number of biological processes and its perturbation leads to developmental defects or diseases. Here, we demonstrate that alternative isoforms of the KDM2A and KDM2B lysine demethylases have the ability to negatively regulate canonical Wnt signaling. These KDM2A and KDM2B isoforms (KDM2A-SF and KDM2B-SF) lack the N-terminal demethylase domain, but they still have the ability to bind to CpG islands in promoters and to interact with their protein partners via their other functional domains. We have observed that KDM2A-SF and KDM2B-SF bind to the promoters of axin 2 and cyclin D1, two canonical Wnt signaling target genes, and repress their activity. Moreover, KDM2A-SF and KDM2B-SF are both able to strongly repress a Wnt-responsive luciferase reporter. The transcriptional repression mediated by KDM2A-SF and KDM2B-SF, but also by KDM2A-LF, is dependent on their DNA binding domain, while the N-terminal demethylase domain is dispensable for this process. Surprisingly, KDM2B-LF is unable to repress both the endogenous promoters and the luciferase reporter. Finally, we show that both KDM2A-SF and KDM2B-SF are able to interact with TCF7L1, one of the transcriptional mediators of canonical Wnt signaling. KDM2A-SF and KDM2B-SF are thus likely to negatively affect the transcription of canonical Wnt signaling target genes by binding to their promoters and by interacting with TCF7L1 and other co-repressors.

• MeSH
• CpG ostrůvky MeSH
• cyklin D1 genetika   metabolismus   MeSH
• F-box proteiny genetika   metabolismus   MeSH
• HEK293 buňky MeSH
• Jumonjiho doména s histondemethylasami genetika   metabolismus   MeSH
• lidé MeSH
• lysin genetika   metabolismus   MeSH
• promotorové oblasti (genetika) * MeSH
• protein - isoformy MeSH
• protein 1 podobný transkripčnímu faktoru 7 genetika   metabolismus   MeSH
• regulace genové exprese * MeSH
• signální dráha Wnt * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Idiopatické střevní záněty jsou heterogenní skupinou chronických zánětlivých onemocnění gastrointestinálního traktu multifaktoriální etiologie. Podle charakteru postižení je dělíme na Crohnovu chorobu a ulcerózní kolitidu. Onemocnění se obvykle rozvíjí ve věku 15–35 let. Specifickou skupinou jsou pacienti pod 10 let věku. V této věkové skupině mívá onemocnění častěji atypický a těžký průběh, spojený s nedostatečnou odpovědí na standardní terapii včetně TNFα inhibitorů, větší prevalencí vážných komplikací a horší prognózou. U těchto pacientů je také vyšší pravděpodobnost odhalení monogenní etiologie. Jedná se převážně o geny s důležitými regulačními funkcemi. Jejich narušení vede k dysregulaci imunitního systému, rozvoji chronického zánětu a mnoha dalším komplikacím, zahrnujícím širokou škálu infekčních i neinfekčních projevů patřících do obrazu primárních imunodeficiencí. Včasná a správná diagnóza je ale v těchto případech klíčová. Umožňuje nám u celé řady z nich zahájení specifické nebo kauzální terapie, která má vliv na snížení závažných komplikací. Z tohoto pohledu je tedy spolupráce gastroenterologa a imunologa klíčová. V následujícím přehledu uvádíme vybrané monogenní primární imunodeficience, které se manifestují především postižením gastrointestinálního traktu. Závěrem jsou prezentovány dvě kazuistiky z našeho pracoviště.

Inflammatory bowel disease is a heterogeneous group of chronic inflammatory disorders with multifactorial ethilogy. They may be assigned as Crohn's disease or as Ulcerative colitis. It is usually manifested between 15–30 years of age. Patients younger than 10 years are specific group with higher risk of the atypical and serisus course of the disease, insufficient response to treatment including TNFα inhibitors, higher prevalence of severe complications and siginificantly poorer prognosis. Moreover, there is also significantly increased probability to reveal monogenic ethiology, which is very often associated with the genes having important regulatory function. Their dysfunction may lead to imune system dysregulation, development of chronic inflammation and broad spectrum of infectious and non-infectious complications belonging to the clinical picture of primary immunodeficiencies From this point of view, the early and appropriate diagnosis is crucial and allows us the initiation of specific or causal therapy in a number of them. This approach leads to reduction a prevention of severe complications. Here, the collaboration of a gastroenterologist and a clinical immunologist is crucial. The selected monogenic primary immunodeficincies manifesting particularly with gastrointestinal tract involvement are presented in following summary. Finally, two case reports from our department are presented.

• MeSH
• antigen CTLA-4 nedostatek   MeSH
• chronická granulomatózní nemoc genetika   komplikace   patofyziologie   MeSH
• Crohnova nemoc diagnóza   etiologie   imunologie   MeSH
• dospělí MeSH
• forkhead transkripční faktory genetika   imunologie   MeSH
• idiopatické střevní záněty * etiologie   imunologie   patofyziologie   MeSH
• interleukin-10 nedostatek   MeSH
• lidé MeSH
• lymfohistiocytóza hemofagocytární diagnóza   etiologie   MeSH
• lymfoproliferativní nemoci komplikace   patofyziologie   terapie   MeSH
• primární imunodeficience * diagnóza   genetika   komplikace   MeSH
• výsledek terapie MeSH
• X-vázaný inhibitor apoptózy genetika   nedostatek   MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• kazuistiky MeSH

• MeSH
• DNA vazebné proteiny genetika   MeSH
• dysgeneze štítné žlázy * diagnostické zobrazování   epidemiologie   farmakoterapie   patologie   MeSH
• genetická predispozice k nemoci * epidemiologie   MeSH
• genetické pozadí * MeSH
• hodnocení rizik MeSH
• incidence MeSH
• lidé MeSH
• mutace MeSH
• myši MeSH
• nádory štítné žlázy genetika   patologie   MeSH
• prognóza MeSH
• proteasomový endopeptidasový komplex genetika   MeSH
• stupeň závažnosti nemoci MeSH
• testy funkce štítné žlázy MeSH
• thyroxin terapeutické užití   MeSH
• transkripční faktor PAX8 genetika   MeSH
• transkripční faktory MeSH
• ultrasonografie dopplerovská metody   MeSH
• vzácné nemoci MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• souhrny MeSH

Generation of neurons in the embryonic neocortex is a balanced process of proliferation and differentiation of neuronal progenitor cells. Canonical Wnt signalling is crucial for expansion of radial glial cells in the ventricular zone and for differentiation of intermediate progenitors in the subventricular zone. We detected abundant expression of two transcrtiption factors mediating canonical Wnt signalling, Tcf7L1 and Tcf7L2, in the ventricular zone of the embryonic neocortex. Conditional knock-out analysis showed that Tcf7L2, but not Tcf7L1, is the principal Wnt mediator important for maintenance of progenitor cell identity in the ventricular zone. In the absence of Tcf7L2, the Wnt activity is reduced, ventricular zone markers Pax6 and Sox2 are downregulated and the neuroepithelial structure is severed due to the loss of apical adherens junctions. This results in decreased proliferation of radial glial cells, the reduced number of intermediate progenitors in the subventricular zone and hypoplastic forebrain. Our data show that canonical Wnt signalling, which is essential for determining the neuroepithelial character of the neocortical ventricular zone, is mediated by Tcf7L2.

• MeSH
• buněčná diferenciace genetika   MeSH
• chlorid-hydrogenuhličitanové antiportéry MeSH
• down regulace genetika   MeSH
• embryo savčí MeSH
• hipokampus cytologie   embryologie   MeSH
• mutace genetika   MeSH
• myši transgenní MeSH
• myši MeSH
• neokortex cytologie   embryologie   MeSH
• nervové kmenové buňky fyziologie   MeSH
• neurogeneze fyziologie   MeSH
• neuroglie MeSH
• neurony fyziologie   MeSH
• počet buněk MeSH
• proliferace buněk genetika   MeSH
• protein 2 podobný transkripčnímu faktoru 7 genetika   metabolismus   MeSH
• proteiny T-boxu metabolismus   MeSH
• proteiny Wnt metabolismus   MeSH
• retinální gangliové buňky fyziologie   MeSH
• signální transdukce genetika   MeSH
• transkripční faktory SOXB1 metabolismus   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

In this review, we address aspects of Wnt, R-Spondin (RSPO) and Hippo signalling, in both healthy and transformed intestinal epithelium. In intestinal stem cells (ISCs), the Wnt pathway is essential for intestinal crypt formation and renewal, whereas RSPO-mediated signalling mainly affects ISC numbers. In human colorectal cancer (CRC), aberrant Wnt signalling is the driving mechanism initiating this type of neoplasia. The signalling role of the RSPO-binding transmembrane proteins, the leucine-rich-repeat-containing G-protein-coupled receptors (LGRs), is possibly more pleiotropic and not only limited to the enhancement of Wnt signalling. There is growing evidence for multiple crosstalk between Hippo and Wnt/β-catenin signalling. In theONstate, Hippo signalling results in serine/threonine phosphorylation of Yes-associated protein (YAP1) and tafazzin (TAZ), promoting formation of the β-catenin destruction complex. In contrast, YAP1 or TAZ dephosphorylation (and YAP1 methylation) results in β-catenin destruction complex deactivation and β-catenin nuclear localization. In the HippoOFFstate, YAP1 and TAZ are engaged with the nuclear β-catenin and participate in the β-catenin-dependent transcription program. Interestingly, YAP1/TAZ are dispensable for intestinal homeostasis; however, upon Wnt pathway hyperactivation, the proteins together with TEA domain (TEAD) transcription factors drive the transcriptional program essential for intestinal cell transformation. In addition, in many CRC cells, YAP1 phosphorylation by YES proto-oncogene 1 tyrosine kinase (YES1) leads to the formation of a transcriptional complex that includes YAP1, β-catenin and T-box 5 (TBX5) DNA-binding protein. YAP1/β-catenin/T-box 5-mediated transcription is necessary for CRC cell proliferation and survival. Interestingly, dishevelled (DVL) appears to be an important mediator involved in both Wnt and Hippo (YAP1/TAZ) signalling and some of the DVL functions were assigned to the nuclear DVL pool. Wnt ligands can trigger alternative signalling that directly involves some of the Hippo pathway components such as YAP1, TAZ and TEADs. By upregulating Wnt pathway agonists, the alternative Wnt signalling can inhibit the canonical Wnt pathway activity.

• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

Our understanding of the origin of animals has been transformed by characterizing their most closely related, unicellular sisters: the choanoflagellates, filastereans, and ichthyosporeans. Together with animals, these lineages make up the Holozoa [1, 2]. Many traits previously considered "animal specific" were subsequently found in other holozoans [3, 4], showing that they evolved before animals, although exactly when is currently uncertain because several key relationships remain unresolved [2, 5]. Here we report the morphology and transcriptome sequencing from three novel unicellular holozoans: Pigoraptor vietnamica and Pigoraptor chileana, which are related to filastereans, and Syssomonas multiformis, which forms a new lineage with Corallochytrium in phylogenomic analyses. All three species are predatory flagellates that feed on large eukaryotic prey, and all three also appear to exhibit complex life histories with several distinct stages, including multicellular clusters. Examination of genes associated with multicellularity in animals showed that the new filastereans contain a cell-adhesion gene repertoire similar to those of other species in this group. Syssomonas multiformis possessed a smaller complement overall but does encode genes absent from the earlier-branching ichthyosporeans. Analysis of the T-box transcription factor domain showed expansion of T-box transcription factors based on combination with a non-T-box domain (a receiver domain), which has not been described outside of vertebrates. This domain and other domains we identified in all unicellular holozoans are part of the two-component signaling system that has been lost in animals, suggesting the continued use of this system in the closest relatives of animals and emphasizing the importance of studying loss of function as well as gain in major evolutionary transitions.

• MeSH
• biologická evoluce * MeSH
• Eukaryota klasifikace   genetika   fyziologie   MeSH
• fetální proteiny genetika   metabolismus   MeSH
• molekulární evoluce MeSH
• predátorské chování * MeSH
• proteiny T-boxu genetika   metabolismus   MeSH
• RNA ribozomální 18S genetika   MeSH
• signální transdukce * MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Acrolein, a highly reactive unsaturated aldehyde, is generated in large amounts during smoking and is best known for its genotoxic capacity. Here, we aimed to assess whether acrolein at concentrations relevant for smokers may also exert immunomodulatory effects that could be relevant in allergy or cancer. In a BALB/c allergy model repeated nasal exposure to acrolein abrogated allergen-specific antibody and cytokine formation, and led to a relative accumulation of regulatory T cells in the lungs. Only the acrolein-treated mice were protected from bronchial hyperreactivity as well as from anaphylactic reactions upon challenge with the specific allergen. Moreover, grafted D2F2 tumor cells grew faster and intratumoral Foxp3+ cell accumulation was observed in these mice compared to sham-treated controls. Results from reporter cell lines suggested that acrolein acts via the aryl-hydrocarbon receptor which could be inhibited by resveratrol and 3'-methoxy-4'-nitroflavone Acrolein- stimulation of human PBMCs increased Foxp3+ expression by T cells which could be antagonized by resveratrol. Our mouse and human data thus revealed that acrolein exerts systemic immunosuppression by promoting Foxp3+ regulatory cells. This provides a novel explanation why smokers have a lower allergy, but higher cancer risk.

• MeSH
• akrolein farmakologie   MeSH
• alergeny imunologie   MeSH
• alergie imunologie   prevence a kontrola   MeSH
• cytokiny metabolismus   MeSH
• forkhead transkripční faktory metabolismus   MeSH
• imunologické faktory farmakologie   MeSH
• modely nemocí na zvířatech MeSH
• myši MeSH
• nádory imunologie   metabolismus   MeSH
• NF-kappa B metabolismus   MeSH
• plíce imunologie   metabolismus   patologie   MeSH
• receptory aromatických uhlovodíků metabolismus   MeSH
• regulační T-lymfocyty imunologie   metabolismus   MeSH
• resveratrol MeSH
• signální transdukce MeSH
• stilbeny farmakologie   MeSH
• tvorba protilátek imunologie   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

T regulatory cells (Tregs) are essential for maintaining tolerance and preventing autoimmune diseases, such as type 1 diabetes (T1D). In our study, we investigated CD25 + FoxP3 + Tregs and thymic FoxP3 + Helios + Tregs in large cohorts of children with T1D at onset and with long-term T1D, and further in their relatives and healthy controls. We observed significantly decreased numbers of CD25 + FoxP3 + Tregs, but not FoxP3 + Helios + Tregs, in long-term patients compared with the control group and T1D onset. Furthermore, long-term T1D patients exhibited highly significant decrease of CD25 expression on both CD25 + FoxP3 + Tregs and FoxP3 + Helios + Tregs, independently on age or the duration of diabetes. A similar reduction of CD25 expression was also found in T1D relatives, more significant in those with positive autoantibodies. Low CD25 expression was associated with impaired signal transducer and activator of transcription 5 (STAT5) phosphorylation after IL-2 exposure. Our results show that the frequency of Tregs is altered in a large cohort of long-term T1D patients, a profound decrease in CD25 expression and altered IL-2 signaling are typical features of Tregs populations in long-term diabetic patients and their relatives.

• MeSH
• biologické markery MeSH
• buněčná diferenciace MeSH
• diabetes mellitus 1. typu diagnóza   etiologie   metabolismus   MeSH
• dítě MeSH
• forkhead transkripční faktory metabolismus   MeSH
• fosforylace MeSH
• imunofenotypizace MeSH
• interleukin-2 metabolismus   farmakologie   MeSH
• kojenec MeSH
• lidé MeSH
• mladiství MeSH
• počet lymfocytů MeSH
• předškolní dítě MeSH
• receptor interleukinu-2 - alfa-podjednotka genetika   metabolismus   MeSH
• regulační T-lymfocyty cytologie   imunologie   metabolismus   MeSH
• signální transdukce MeSH
• studie případů a kontrol MeSH
• thymocyty cytologie   imunologie   metabolismus   MeSH
• transkripční faktor STAT5 MeSH
• věkové faktory MeSH
• Check Tag
• dítě MeSH
• kojenec MeSH
• lidé MeSH
• mladiství MeSH
• mužské pohlaví MeSH
• předškolní dítě MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

The differentiation of embryonic stem cells is associated with extensive changes in gene expression. It is not yet clear whether these changes are the result of binary switch-like mechanisms or that of continuous and progressive variation. Here, I have used immunostaining and single molecule RNA fluorescence in situ hybridization (FISH) to assess changes in the expression of the well-known pluripotency-associated gene Pou5f1 (also known as Oct4) and early differentiation markers Sox1 and T-brachyury in single cells during the early steps of differentiation of mouse embryonic stem cells. I found extensive overlap between the expression of Pou5f1/Sox1 or Pou5f1/T-brachyury shortly after the initiation of differentiation towards either the neuronal or the mesendodermal lineage, but no evidence of correlation between their respective expression levels. Quantitative analysis of transcriptional output at the sites of nascent transcription revealed that Pou5f1 and Sox1 were transcribed in pulses and that embryonic stem cell differentiation was accompanied by changes in pulsing frequencies. The progressive induction of Sox1 was further associated with an increase in the average size of individual transcriptional bursts. Surprisingly, single cells that actively and simultaneously transcribe both the pluripotency- and the lineage-associated genes could easily be found in the differentiating population. The results presented here show for the first time that lineage priming can occur in cells that are actively transcribing a pluripotent marker. Furthermore, they suggest that this process is associated with changes in transcriptional dynamics.

• MeSH
• analýza jednotlivých buněk * MeSH
• buněčná diferenciace genetika   MeSH
• buněčný rodokmen genetika   MeSH
• embryonální kmenové buňky cytologie   metabolismus   MeSH
• fetální proteiny biosyntéza   genetika   MeSH
• hybridizace in situ fluorescenční MeSH
• myši MeSH
• oktamerní transkripční faktor 3 biosyntéza   genetika   MeSH
• pluripotentní kmenové buňky cytologie   metabolismus   MeSH
• proteiny T-boxu biosyntéza   genetika   MeSH
• transkripční faktory SOXB1 biosyntéza   genetika   MeSH
• vývojová regulace genové exprese MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH