Interaction between an antigen-presenting cell and a T cell, and their subsequent conjugation are a prerequisite for the formation of the immunological synapse and productive, antigen-dependent activation of T cells. This initial interaction is accompanied by recognition of the presented antigen by the T cell receptor, and by changes in the morphology of the interacting cells and in actin cytoskeleton structure in the site of interaction. The experimental protocol below describes a simple assay for quantitative assessment of antigen-presenting cells-T cell conjugation using confocal microscopy or flow cytometry.

• Klíčová slova
• B3Z, Confocal microscopy, Conjugation assay, Flow cytometry, Immunological synapse, MutuDC,
• MeSH
• aktivace lymfocytů MeSH
• antigen prezentující buňky * MeSH
• imunologické synapse fyziologie   MeSH
• mikrofilamenta MeSH
• receptory antigenů T-buněk MeSH
• T-lymfocyty * MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• receptory antigenů T-buněk MeSH

Antigen-presenting cells (APCs) are master regulators of the immune response by directly interacting with T cells to orchestrate distinct functional outcomes. Several types of professional APC exist, including conventional dendritic cells, B cells and macrophages, and numerous other cell types have non-classical roles in antigen presentation, such as thymic epithelial cells, endothelial cells and granulocytes. Accumulating evidence indicates the presence of a new family of APCs marked by the lineage-specifying transcription factor retinoic acid receptor-related orphan receptor-γt (RORγt) and demonstrates that these APCs have key roles in shaping immunity, inflammation and tolerance, particularly in the context of host-microorganism interactions. These RORγt+ APCs include subsets of group 3 innate lymphoid cells, extrathymic autoimmune regulator-expressing cells and, potentially, other emerging populations. Here, we summarize the major findings that led to the discovery of these RORγt+ APCs and their associated functions. We discuss discordance in recent reports and identify gaps in our knowledge in this burgeoning field, which has tremendous potential to advance our understanding of fundamental immune concepts.

• MeSH
• antigen prezentující buňky metabolismus   MeSH
• endoteliální buňky MeSH
• jaderné receptory - podrodina 1, skupina F, člen 3 * metabolismus   MeSH
• lidé MeSH
• lymfocyty * MeSH
• přirozená imunita MeSH
• transportní proteiny metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• jaderné receptory - podrodina 1, skupina F, člen 3 * MeSH
• transportní proteiny MeSH

The presence of professional antigen-presenting cells in tumours can influence their further spreading. Location of cells exhibiting a specific marker of Langerhans cells--Langerin, and the 175 kD mannose receptor as a marker of dendritic cells of non-Langerhans type and macrophages, was studied using double staining in the normal human epidermis and in basal cell carcinomas. The Langerin-positive cells strictly colonized the epidermis and no cells were found in the dermis, where 175 kD mannose receptor-exhibiting cells were present. Very rare elements in the epidermal/dermal interface were positive for both markers. A low incidence of Langerin-positive cells was found in tumours and 1/3 of studied carcinomas were even Langerhans cell-free. The extraepithelial presence of Langerin-positive cells forming contacts with dendrite-like protrusions of 175 kD mannose receptor-exhibiting cells was found in connective tissue surrounding the tumour epithelium and indicates possible cooperation of both elements.

• MeSH
• antigen prezentující buňky metabolismus   MeSH
• antigeny povrchové metabolismus   MeSH
• bazocelulární karcinom metabolismus   MeSH
• CD antigeny MeSH
• epidermis metabolismus   MeSH
• imunohistochemie MeSH
• kůže metabolismus   MeSH
• Langerhansovy buňky metabolismus   MeSH
• lektiny typu C metabolismus   MeSH
• lektiny vázající mannosu metabolismus   MeSH
• lidé MeSH
• nádory kůže metabolismus   MeSH
• receptor mannózy MeSH
• receptory buněčného povrchu metabolismus   MeSH
• škára metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH
• Názvy látek
• antigeny povrchové MeSH
• CD antigeny MeSH
• CD207 protein, human MeSH Prohlížeč
• lektiny typu C MeSH
• lektiny vázající mannosu MeSH
• receptor mannózy MeSH
• receptory buněčného povrchu MeSH

The critical role of Bruton tyrosine kinase (Btk) in B cells has been documented by the block of B-cell development in X-linked agammaglobulinemia (XLA). Less is known about Btk function in myeloid cells. Several pieces of evidence indicate that Btk is a component of Toll-like receptor (TLR) signaling. We analyzed whether Btk deficiency in XLA is associated with an impaired dendritic cell (DC) compartment or defective TLR signaling. We analyzed the expression of TLRs 1 to 9 on myeloid DCs generated from XLA patients and evaluated their response to activation by specific TLR agonists. We show that XLA patients have normal numbers of circulating DCs. Btk-deficient DCs have no defect in response to stimulation of TLRs 1/2, 2/6, 3, 4, and 5 but display a profound impairment of IL-6 and TNF-alpha production in response to stimulation by TLR-8 cognate agonist, ssRNA. These findings may provide an explanation for the susceptibility to enteroviral infections in XLA patients.

• MeSH
• agamaglobulinemie metabolismus   MeSH
• antigen prezentující buňky metabolismus   MeSH
• buněčná diferenciace MeSH
• dendritické buňky cytologie   metabolismus   MeSH
• interleukin-6 biosyntéza   MeSH
• lidé MeSH
• TNF-alfa biosyntéza   MeSH
• toll-like receptor 8 agonisté   genetika   metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• interleukin-6 MeSH
• TLR8 protein, human MeSH Prohlížeč
• TNF-alfa MeSH
• toll-like receptor 8 MeSH

Toll-like receptors (TLR) are key components of innate immune system. As TLR activation could induce potentially harmful inflammatory response, activation of TLR signaling pathways has to be under tight control. Besides other control mechanisms, an inhibitory function of murine TLR4 splice variants was recently demonstrated. In this study we investigated expression of four TLR4 splice variants in human antigen presenting cells (APC). Furthermore, we studied modification in TLR4 splice variants expression in APC in cystic fibrosis (CF) patients chronically infected by Gram-negative bacteria. We developed a novel reliable real-time PCR detection system that allowed monitoring of individual TLR4 splice variants expression. In APC from healthy donors we detected a characteristic transient increase of two out of four splice variants after lipopolysaccharide (LPS) stimulation. Similarly to murine TLR4, one of these variants, NM 003266, might translate to a potentially inhibitory protein. In contrast to controls, CF monocytes had significantly changed LPS-induced expression of TLR4 gene and its variants including reduced ability to up-regulate the expression of the potentially inhibitory variant upon stimulation. In accordance with this observation, monocytes from CF patients produced significantly more tumor necrosis factor after LPS stimulation than healthy controls. Our results thus describe the kinetics of TLR4 splicing variants expression after LPS stimulation and indicate a possible alteration of its regulation in CF patients.

• MeSH
• alternativní sestřih * MeSH
• antigen prezentující buňky chemie   imunologie   MeSH
• cystická fibróza imunologie   MeSH
• dendritické buňky imunologie   MeSH
• dospělí MeSH
• kultivované buňky MeSH
• lidé MeSH
• lipopolysacharidy imunologie   MeSH
• messenger RNA analýza   MeSH
• monocyty imunologie   MeSH
• polymerázová řetězová reakce s reverzní transkripcí metody   MeSH
• regulace genové exprese MeSH
• stanovení celkové genové exprese MeSH
• TNF-alfa biosyntéza   MeSH
• toll-like receptor 4 biosyntéza   genetika   MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• lipopolysacharidy MeSH
• messenger RNA MeSH
• TNF-alfa MeSH
• toll-like receptor 4 MeSH

The Bordetella adenylate cyclase toxin-hemolysin (CyaA; also called ACT or AC-Hly) targets CD11b-expressing phagocytes and translocates into their cytosol an adenylyl cyclase (AC) that hijacks cellular signaling by conversion of ATP to cyclic AMP (cAMP). Intriguingly, insertion of large passenger peptides removes the enzymatic activity but not the cell-invasive capacity of the AC domain. This has repeatedly been exploited for delivery of heterologous antigens into the cytosolic pathway of CD11b-expressing dendritic cells by CyaA/AC(-) toxoids, thus enabling their processing and presentation on major histocompatibility complex (MHC) class I molecules to cytotoxic CD8(+) T lymphocytes (CTLs). We produced a set of toxoids with overlapping deletions within the first 371 residues of CyaA and showed that the structure of the AC enzyme does not contain any sequences indispensable for its translocation across target cell membrane. Moreover, replacement of the AC domain (residues 1 to 371) with heterologous polypeptides of 40, 146, or 203 residues yielded CyaAΔAC constructs that delivered passenger CTL epitopes into antigen-presenting cells (APCs) and induced strong antigen-specific CD8(+) CTL responses in vivo in mice and ex vivo in human peripheral blood mononuclear cell cultures. This shows that the RTX (repeats in toxin) hemolysin moiety, consisting of residues 374 to 1706 of CyaA, harbors all structural information involved in translocation of the N-terminal AC domain across target cell membranes. These results decipher the extraordinary capacity of the AC domain of CyaA to transport large heterologous cargo polypeptides into the cytosol of CD11b(+) target cells and pave the way for the construction of CyaAΔAC-based polyvalent immunotherapeutic T cell vaccines.

• MeSH
• adenylátcyklasový toxin genetika   metabolismus   MeSH
• antigen prezentující buňky metabolismus   MeSH
• buněčná membrána metabolismus   MeSH
• CD8-pozitivní T-lymfocyty imunologie   MeSH
• dendritické buňky metabolismus   MeSH
• kultivované buňky MeSH
• lidé MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• rekombinantní proteiny genetika   metabolismus   MeSH
• sekvenční delece MeSH
• toxoidy genetika   metabolismus   MeSH
• transport proteinů MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• adenylátcyklasový toxin MeSH
• rekombinantní proteiny MeSH
• toxoidy MeSH

ISG20L2, a 3' to 5' exoribonuclease previously associated with ribosome biogenesis, is identified here in activated T cells as an enzyme with a preferential affinity for uridylated miRNA substrates. This enzyme is upregulated in T lymphocytes upon TCR and IFN type I stimulation and appears to be involved in regulating T cell function. ISG20L2 silencing leads to an increased basal expression of CD69 and induces greater IL2 secretion. However, ISG20L2 absence impairs CD25 upregulation, CD3 synaptic accumulation and MTOC translocation towards the antigen-presenting cell during immune synapsis. Remarkably, ISG20L2 controls the expression of immunoregulatory molecules, such as AHR, NKG2D, CTLA-4, CD137, TIM-3, PD-L1 or PD-1, which show increased levels in ISG20L2 knockout T cells. The dysregulation observed in these key molecules for T cell responses support a role for this exonuclease as a novel RNA-based regulator of T cell function.

• Klíčová slova
• Exonuclease, ISG20L2, Immunoregulatory, T cell,
• MeSH
• aktivace lymfocytů * MeSH
• antigen prezentující buňky MeSH
• endonukleasy MeSH
• lidé MeSH
• mikro RNA * genetika   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• endonukleasy MeSH
• mikro RNA * MeSH

The autoimmune regulator (Aire) serves an essential function for T cell tolerance by promoting the "promiscuous" expression of tissue antigens in thymic epithelial cells. Aire is also detected in rare cells in peripheral lymphoid organs, but the identity of these cells is poorly understood. Here, we report that Aire protein-expressing cells in lymph nodes exhibit typical group 3 innate lymphoid cell (ILC3) characteristics such as lymphoid morphology, absence of "classical" hematopoietic lineage markers, and dependence on RORγt. Aire+ cells are more frequent among lineage-negative RORγt+ cells of peripheral lymph nodes as compared with mucosa-draining lymph nodes, display a unique Aire-dependent transcriptional signature, express high surface levels of MHCII and costimulatory molecules, and efficiently present an endogenously expressed model antigen to CD4+ T cells. These findings define a novel type of ILC3-like cells with potent APC features, suggesting that these cells serve a function in the control of T cell responses.

• MeSH
• adhezní molekula epiteliálních buněk metabolismus   MeSH
• antigen prezentující buňky imunologie   MeSH
• antigeny CD11 metabolismus   MeSH
• fenotyp MeSH
• genetická transkripce MeSH
• histokompatibilita - antigeny třídy II metabolismus   MeSH
• jaderné receptory - podrodina 1, skupina F, člen 3 metabolismus   MeSH
• lymfatické uzliny cytologie   MeSH
• lymfocyty imunologie   metabolismus   MeSH
• myši inbrední BALB C MeSH
• myši knockoutované MeSH
• myši MeSH
• přirozená imunita MeSH
• protein AIRE MeSH
• regulace genové exprese MeSH
• transkripční faktory genetika   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• adhezní molekula epiteliálních buněk MeSH
• antigeny CD11 MeSH
• histokompatibilita - antigeny třídy II MeSH
• Itgax protein, mouse MeSH Prohlížeč
• jaderné receptory - podrodina 1, skupina F, člen 3 MeSH
• Rorc protein, mouse MeSH Prohlížeč
• transkripční faktory MeSH

• MeSH
• antigen prezentující buňky imunologie   MeSH
• antigeny imunologie   MeSH
• B-lymfocyty imunologie   MeSH
• fagocyty imunologie   MeSH
• hlavní histokompatibilní komplex MeSH
• lidé MeSH
• receptory antigenů B-buněk imunologie   MeSH
• receptory antigenů imunologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• anglický abstrakt MeSH
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• antigeny MeSH
• receptory antigenů B-buněk MeSH
• receptory antigenů MeSH

Dendritic cells (DC) are very heterogenous population of professional antigen-presenting cells. Precursor cells migrate from bone marrow to peripheral tissues, where immature DC ingest pathogenic microorganisms and then migrate to secondary lymphoid organs. DC differentiate into mature cells that are capable to prime naive T lymphocytes. DC can be used for immunotherapy of cancer and infectious diseases. Transduction of DC by recombinant viral vectors expressing tumor associated antigens (TAA) can result in efficient antigen presentation to T lymphocytes. DC transduced with recombinant vaccinia virus expressing E7 oncoprotein of human papilloma virus 16 are able to protect mice against the growth of syngeneic papillomavirus transformed tumor cells TC1. Antitumor effect was observed also with nonreplicating viruses.

• MeSH
• antigen prezentující buňky imunologie   MeSH
• antigeny nádorové genetika   metabolismus   MeSH
• dendritické buňky imunologie   MeSH
• genetické vektory * MeSH
• lidé MeSH
• transdukce genetická * MeSH
• virus vakcinie * MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• anglický abstrakt MeSH
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antigeny nádorové MeSH