Interferon-γ receptor 2 is a cell-surface receptor that is required for interferon-γ signalling and therefore plays a critical immunoregulatory role in innate and adaptive immunity against viral and also bacterial and protozoal infections. A crystal structure of the extracellular part of human interferon-γ receptor 2 (IFNγR2) was solved by molecular replacement at 1.8 Å resolution. Similar to other class 2 receptors, IFNγR2 has two fibronectin type III domains. The characteristic structural features of IFNγR2 are concentrated in its N-terminal domain: an extensive π-cation motif of stacked residues KWRWRH, a NAG-W-NAG sandwich (where NAG stands for N-acetyl-D-glucosamine) and finally a helix formed by residues 78-85, which is unique among class 2 receptors. Mass spectrometry and mutational analyses showed the importance of N-linked glycosylation to the stability of the protein and confirmed the presence of two disulfide bonds. Structure-based bioinformatic analysis revealed independent evolutionary behaviour of both receptor domains and, together with multiple sequence alignment, identified putative binding sites for interferon-γ and receptor 1, the ligands of IFNγR2.

• Klíčová slova
• class 2 cytokine receptors, fibronectin type III domain, interferon-γ receptor 2,
• MeSH
• aminokyselinové motivy MeSH
• disulfidy chemie   MeSH
• glykosylace MeSH
• konformace proteinů MeSH
• krystalografie rentgenová MeSH
• lidé MeSH
• molekulární modely MeSH
• proteinové domény MeSH
• receptory interferonů chemie   MeSH
• sbalování proteinů MeSH
• stabilita proteinů MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• disulfidy MeSH
• IFNGR2 protein, human MeSH Prohlížeč
• receptory interferonů MeSH

We describe a computer-based protocol to design protein mutations increasing binding affinity between ligand and its receptor. The method was applied to mutate interferon-γ receptor 1 (IFN-γ-Rx) to increase its affinity to natural ligand IFN-γ, protein important for innate immunity. We analyzed all four available crystal structures of the IFN-γ-Rx/IFN-γ complex to identify 40 receptor residues forming the interface with IFN-γ. For these 40 residues, we performed computational mutation analysis by substituting each of the interface receptor residues by the remaining standard amino acids. The corresponding changes of the free energy were calculated by a protocol consisting of FoldX and molecular dynamics calculations. Based on the computed changes of the free energy and on sequence conservation criteria obtained by the analysis of 32 receptor sequences from 19 different species, we selected 14 receptor variants predicted to increase the receptor affinity to IFN-γ. These variants were expressed as recombinant proteins in Escherichia coli, and their affinities to IFN-γ were determined experimentally by surface plasmon resonance (SPR). The SPR measurements showed that the simple computational protocol succeeded in finding two receptor variants with affinity to IFN-γ increased about fivefold compared to the wild-type receptor.

• MeSH
• interferon gama chemie   genetika   metabolismus   MeSH
• lidé MeSH
• povrchová plasmonová rezonance MeSH
• receptor interferonu gama MeSH
• receptory interferonů chemie   genetika   metabolismus   MeSH
• sbalování proteinů * MeSH
• simulace molekulární dynamiky * MeSH
• substituce aminokyselin MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• IFNG protein, human MeSH Prohlížeč
• interferon gama MeSH
• receptory interferonů MeSH

Retinal disorders represent the main cause of decreased quality of vision and even blindness worldwide. The loss of retinal cells causes irreversible damage of the retina, and there are currently no effective treatment protocols for most retinal degenerative diseases. A promising approach for the treatment of retinal disorders is represented by stem cell-based therapy. The perspective candidates are mesenchymal stem cells (MSCs), which can differentiate into multiple cell types and produce a number of trophic and growth factors. In this study, we show the potential of murine bone marrow-derived MSCs to differentiate into cells expressing retinal markers and we identify the key supportive role of interferon-γ (IFN-γ) in the differentiation process. MSCs were cultured for 7 days with retinal extract and supernatant from T-cell mitogen concanavalin A-stimulated splenocytes, simulating the inflammatory site of retinal damage. MSCs cultured in such conditions differentiated to the cells expressing retinal cell markers such as rhodopsin, S antigen, retinaldehyde-binding protein, calbindin 2, recoverin, and retinal pigment epithelium 65. To identify a supportive molecule in the supernatants from activated spleen cells, MSCs were cultured with retinal extract in the presence of various T-cell cytokines. The expression of retinal markers was enhanced only in the presence of IFN-γ, and the supportive role of spleen cell supernatants was abrogated with the neutralization antibody anti-IFN-γ. In addition, differentiated MSCs were able to express a number of neurotrophic factors, which are important for retinal regeneration. Taken together, the results show that MSCs can differentiate into cells expressing retinal markers and that this differentiation process is supported by IFN-γ.

• Klíčová slova
• differentiation, interferon-γ, mesenchymal stem cell, neurotrophic factor, retina, rhodopsin,
• MeSH
• buněčná diferenciace * MeSH
• cis-trans-isomerasy genetika   metabolismus   MeSH
• interferon gama farmakologie   MeSH
• kalbindin 2 genetika   metabolismus   MeSH
• kultivované buňky MeSH
• mezenchymální kmenové buňky cytologie   účinky léků   metabolismus   MeSH
• myši inbrední BALB C MeSH
• myši MeSH
• rekoverin genetika   metabolismus   MeSH
• retina cytologie   metabolismus   MeSH
• rodopsin genetika   metabolismus   MeSH
• transportní proteiny genetika   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• 11-cis-retinal-binding protein MeSH Prohlížeč
• cis-trans-isomerasy MeSH
• interferon gama MeSH
• kalbindin 2 MeSH
• rekoverin MeSH
• retinoid isomerohydrolase MeSH Prohlížeč
• rodopsin MeSH
• transportní proteiny MeSH

Concerning the key role of interferon-γ (IFN-γ) in the protective immunity against Mycobacterium tuberculosis, we aimed to find the possible association between single nucleotide polymorphism of IFN-γ +874T/A (rs61923114) and pulmonary tuberculosis (PTB). This case-control study was performed on 142 PTB patients and 166 healthy subjects. Genotype analysis was done using amplification refractory mutation system-PCR (ARMS-PCR). We found that the AA genotype of +874A/T IFN-γ is a risk factor for PTB (OR = 3.333, 95% CI = 1.537-7.236, p=0.002). The results showed that the +874A allele frequency was higher in PTB than in normal subjects (OR = 1.561, 95% CI = 1.134-2.480, p=0.007). In conclusion, significant association was found between the IFN-γ +874T/A polymorphism (rs61923114) and susceptibility to PTB in a sample of Iranian population.

• MeSH
• frekvence genu MeSH
• genetická predispozice k nemoci MeSH
• interferon gama genetika   MeSH
• jednonukleotidový polymorfismus * MeSH
• lidé středního věku MeSH
• lidé MeSH
• plicní tuberkulóza genetika   MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Írán MeSH
• Názvy látek
• interferon gama MeSH

IFN-γ is a pleiotropic cytokine crucial for both innate and adaptive immunity, which also plays a critical role in immunological surveillance of cancer. Genetic defects or gene silencing in the IFN-γ signal transduction pathways as well as in the expression of IFN-γ-regulated genes represent frequent mechanisms by which tumour cells can escape from immune responses. Epigenetic control of the IFN-γ signalling pathway activation associated with epigenetic changes in the corresponding regulatory gene regions, such as chromatin remodelling, histone acetylation and methylation, and DNA demethylation is frequently dysregulated in tumour cells. Epigenetic silencing of the IFN-γ regulatory pathway components, as well as of the IFN-γ-regulated genes crucial for tumour cell recognition or induction of anti-tumour immune responses, has been documented in various cancer models. Expression of both IFN-γ signalling pathway components and selected IFN-γ-regulated genes can be influenced by epigenetic modifiers, namely DNA methyltransferase and histone deacetylase inhibitors. These agents thus can mimic, restore, or boost the immunomodulatory effects of IFN-γ in tumour cells, which can contribute to their anti-tumour therapeutic efficacies and justifies their potential use in combined epigenetic therapy with immunotherapeutic approaches.

• MeSH
• epigeneze genetická * MeSH
• interferon gama metabolismus   MeSH
• lidé MeSH
• metylace DNA genetika   MeSH
• nádory genetika   metabolismus   MeSH
• restrukturace chromatinu MeSH
• signální transdukce * MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• interferon gama MeSH

BACKGROUND: Interferon gamma (IFN-γ) is one of the key regulatory cytokines that has a significant effect on immune responses. It may be important in the chronic inflammatory diseases such as periodontitis in which increased IFN-γ levels were found. The aim of this study was to analyze +874A/T polymorphism in the IFN-γ gene and its associations with the presence of periodontopathic bacteria and susceptibility to generalized chronic periodontitis (CP). METHODS: A total of 498 unrelated Czech white subjects were included in the present study. Genomic DNA was obtained from the peripheral blood of 244 patients with CP and 254 healthy subjects. The IFN-γ +874A/T polymorphism was determined by amplification refractory mutation system-polymerase chain reaction (ARMS-PCR). Subgingival bacterial colonization (A. actinomycetemcomitans, P. gingivalis, P. intermedia, T. forsythia, T. denticola, P. micros, F. nucleatum in subgingival pockets) was investigated by the DNA-microarray based periodontal pathogen detection kit in a subgroup of subjects (N=110). RESULTS: Our results showed no differences in the allele and genotype frequencies of the IFN-γ +874A/T polymorphism between patients with CP and controls (P>0.05). Although we found significant differences in the occurrence of periodontal bacteria between patients with CP and healthy controls (from P<0.00001 to P<0.05), no significant association between IFN-γ +874A/T polymorphism and periodontal pathogens was observed in any group. CONCLUSIONS: In conclusion, these findings indicate that putative functional variant in the IFN-γ is not associated with susceptibility to chronic periodontitis or microbial composition in the Czech population.

• MeSH
• alely MeSH
• Bacteria genetika   MeSH
• chronická parodontitida genetika   imunologie   mikrobiologie   MeSH
• dospělí MeSH
• genotyp MeSH
• interferon gama genetika   MeSH
• lidé středního věku MeSH
• lidé MeSH
• polymerázová řetězová reakce MeSH
• polymorfismus genetický * MeSH
• rozdělení chí kvadrát MeSH
• ústa mikrobiologie   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika MeSH
• Názvy látek
• interferon gama MeSH

The aim of this study was to investigate the impact of thymic dysplasia on the phenotypic and functional characteristics of T cells in patients with 22q11.2 deletion syndrome, including T-cell phenotype, transcriptional profile, cytokine production, as well as the possibility of utilizing IL-7 to recover their numbers and function. We found a strong bias towards Th1 response in pediatric and young adult 22q11.2DS patients, expansion of CXCR5+ follicular helper cells and CXCR3+CCR6- Th1 cells, increased production of cytokines IFN-γ, IL-10, IL-2, IL-21 and TNF-α. This Th1 skew was primarily driven by expanded terminally differentiated T cells. IL-7 further reduced naive T cells, increased cytokine production and caused an upregulation of exhaustion markers. Thus, Th1 bias in T cell populations persists from infancy into adolescence and is accompanied by accelerated maturation of T cells into memory stages. This phenotype is exacerbated by IL-7 which causes further decrease in naïve T cells in vitro.

• Klíčová slova
• Exhaustion, IFN-γ, IL-7, Immunodeficiency, RNA-seq, Spectral cytometry, thymus,
• MeSH
• cytokiny MeSH
• DiGeorgeův syndrom * MeSH
• dítě MeSH
• interferon gama * MeSH
• interleukin-7 MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• paměťové T-buňky MeSH
• Th1 buňky MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• cytokiny MeSH
• interferon gama * MeSH
• interleukin-7 MeSH

Trilobolide (TB), a sesquiterpene lactone isolated from Laser trilobum is an inhibitor of sarco/endoplasmic reticulum Ca(2+)-ATPase (SERCA). We have found that upon the in vitro exposure to TB, rodent peritoneal cells and human peripheral blood mononuclear cells secrete high amounts of IFN-γ. The effect is associated with the stimulation of high output NO biosynthesis in rat cells. The stimulatory potential of TB depends on the activation of MAP kinases p38 and ERK1/2, and transcription factor NF-κB. BAPTA-AM, a chelator of the intracellular calcium, remained without any effect on the secretion of IFN-γ triggered by TB. These results demonstrate that TB is a potent immunostimulatory agent.

• MeSH
• butyráty chemie   farmakologie   MeSH
• EGTA analogy a deriváty   farmakologie   MeSH
• furany chemie   farmakologie   MeSH
• interferon gama metabolismus   MeSH
• krysa rodu Rattus MeSH
• lidé MeSH
• molekulární struktura MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• neutrofily účinky léků   metabolismus   MeSH
• oxid dusnatý metabolismus   MeSH
• peritoneum cytologie   MeSH
• potkani inbrední LEW MeSH
• viabilita buněk MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• lidé MeSH
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• 1,2-bis(2-aminophenoxy)ethane N,N,N',N'-tetraacetic acid acetoxymethyl ester MeSH Prohlížeč
• butyráty MeSH
• EGTA MeSH
• furany MeSH
• interferon gama MeSH
• oxid dusnatý MeSH
• trilobolide MeSH Prohlížeč

The aim of this study was to investigate the effects of systemically administered bone-marrow-derived mesenchymal stromal cells (MSCs) on the early acute phase of inflammation in the alkali-burned eye. Mice with damaged eyes were either untreated or treated 24 h after the injury with an intravenous administration of fluorescent-dye-labeled MSCs that were unstimulated or pretreated with interleukin-1α (IL-1α), transforming growth factor-β (TGF-β), or interferon-γ (IFN-γ). Analysis of cell suspensions prepared from the eyes of treated mice on day 3 after the alkali burn revealed that MSCs specifically migrated to the damaged eye and that the number of labeled MSCs was more than 30-times higher in damaged eyes compared with control eyes. The study of the composition of the leukocyte populations within the damaged eyes showed that all types of tested MSCs slightly decreased the number of infiltrating lymphoid and myeloid cells, but only MSCs pretreated with IFN-γ significantly decreased the percentage of eye-infiltrating cells with a more profound effect on myeloid cells. Determining cytokine and NO production in the damaged eyes confirmed that the most effective immunomodulation was achieved with MSCs pretreated with IFN-γ, which significantly decreased the levels of the proinflammatory molecules IL-1α, IL-6, and NO. Taken together, the results show that systemically administered MSCs specifically migrate to the damaged eye and that IFN-γ-pretreated MSCs are superior in inhibiting the acute phase of inflammation, decreasing leukocyte infiltration, and attenuating the early inflammatory environment.

• MeSH
• alkálie toxicita   MeSH
• alografty MeSH
• antivirové látky farmakologie   MeSH
• chemické popálení patologie   terapie   MeSH
• interferon gama farmakologie   MeSH
• interleukin-1alfa metabolismus   MeSH
• myši inbrední BALB C MeSH
• myši MeSH
• nika kmenových buněk * MeSH
• popálení oka chemicky indukované   metabolismus   patologie   terapie   MeSH
• transformující růstový faktor beta metabolismus   MeSH
• transplantace mezenchymálních kmenových buněk * MeSH
• zánět chemicky indukované   metabolismus   terapie   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• alkálie MeSH
• antivirové látky MeSH
• interferon gama MeSH
• interleukin-1alfa MeSH
• transformující růstový faktor beta MeSH

Combining computational and experimental tools, we present a new strategy for designing high affinity variants of a binding protein. The affinity is increased by mutating residues not at the interface, but at positions lining internal cavities of one of the interacting molecules. Filling the cavities lowers flexibility of the binding protein, possibly reducing entropic penalty of binding. The approach was tested using the interferon-γ receptor 1 (IFNγR1) complex with IFNγ as a model. Mutations were selected from 52 amino acid positions lining the IFNγR1 internal cavities by using a protocol based on FoldX prediction of free energy changes. The final four mutations filling the IFNγR1 cavities and potentially improving the affinity to IFNγ were expressed, purified, and refolded, and their affinity towards IFNγ was measured by SPR. While individual cavity mutations yielded receptor constructs exhibiting only slight increase of affinity compared to WT, combinations of these mutations with previously characterized variant N96W led to a significant sevenfold increase. The affinity increase in the high affinity receptor variant N96W+V35L is linked to the restriction of its molecular fluctuations in the unbound state. The results demonstrate that mutating cavity residues is a viable strategy for designing protein variants with increased affinity.

• MeSH
• interferon gama chemie   metabolismus   MeSH
• lidé MeSH
• missense mutace MeSH
• molekulární modely * MeSH
• receptor interferonu gama MeSH
• receptory interferonů chemie   genetika   metabolismus   MeSH
• sbalování proteinů * MeSH
• substituce aminokyselin * MeSH
• vazba proteinů MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• IFNG protein, human MeSH Prohlížeč
• interferon gama MeSH
• receptory interferonů MeSH