on‐surface synthesis
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PURPOSE: Docetaxel resistance is a significant obstacle in the treatment of prostate cancer (PCa), resulting in unfavorable patient prognoses. Intratumoral heterogeneity, often associated with epithelial-to-mesenchymal transition (EMT), has previously emerged as a phenomenon that facilitates adaptation to various stimuli, thus promoting cancer cell diversity and eventually resistance to chemotherapy, including docetaxel. Hence, understanding intratumoral heterogeneity is essential for better patient prognosis and the development of personalized treatment strategies. METHODS: To address this, we employed a high-throughput single-cell flow cytometry approach to identify a specific surface fingerprint associated with docetaxel-resistance in PCa cells and complemented it with proteomic analysis of extracellular vesicles. We further validated selected antigens using docetaxel-resistant patient-derived xenografts in vivo and probed primary PCa specimens to interrogate of their surface fingerprint. RESULTS: Our approaches revealed a 6-molecule surface fingerprint linked to docetaxel resistance in primary PCa specimens. We observed consistent overexpression of CD95 (FAS/APO-1), and SSEA-4 surface antigens in both in vitro and in vivo docetaxel-resistant models, which was also observed in a cell subpopulation of primary PCa tumors exhibiting EMT features. Furthermore, CD95, along with the essential enzymes involved in SSEA-4 synthesis, ST3GAL1, and ST3GAL2, displayed a significant increase in patients with PCa undergoing docetaxel-based therapy, correlating with poor survival outcomes. CONCLUSION: In summary, we demonstrate that the identified 6-molecule surface fingerprint associated with docetaxel resistance pre-exists in a subpopulation of primary PCa tumors before docetaxel treatment. Thus, this fingerprint warrants further validation as a promising predictive tool for docetaxel resistance in PCa patients prior to therapy initiation.
- MeSH
- chemorezistence * MeSH
- docetaxel * farmakologie terapeutické užití MeSH
- epitelo-mezenchymální tranzice účinky léků MeSH
- lidé MeSH
- myši MeSH
- nádorové buněčné linie MeSH
- nádory prostaty * patologie farmakoterapie metabolismus MeSH
- protinádorové látky farmakologie terapeutické užití MeSH
- xenogenní modely - testy protinádorové aktivity MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
DC-SIGN, a C-type lectin receptor expressed on immune cells, is considered a promising target for immunomodulatory and antiviral therapies. While mannose-based glycomimetics have been extensively studied as DC-SIGN ligands, fucose-based strategies remain underexplored. This study explores the fucosylation of linear alcohols and sugars using eight different fucosyl donors, aiming at designing strategies for the development of fucose-based glycomimetics targeting DC-SIGN. Four types of leaving groups and two different acyl-based protecting groups on the donors were tested. The glycosylation of 3-azidopropan-1-ol exclusively yielded the β-anomer, demonstrating high stereoselectivity. The azido group in the product is versatile, allowing for direct click chemistry reactions or reduction to an amine for further functionalization. Both types of reactions were demonstrated in a model reaction. In the glycosylation of a sugar, a disaccharide moiety of Lewis X antigen was selected as a target molecule. Only one of the eight tested fucosyl donors worked well in this reaction and provided the product in a reasonable yield. The disaccharide was also equipped with the 3-azidopropyl linker, facilitating future modifications. Finally, NMR studies confirmed compatibility of the linker with canonical Ca2+-dependent carbohydrate binding to DC-SIGN, suggesting potential for further development of fucose-based glycomimetics targeting this C-type lectin receptor.
- MeSH
- fukosa * chemie MeSH
- glykosidy * chemie chemická syntéza farmakologie metabolismus MeSH
- glykosylace MeSH
- lektiny typu C * metabolismus antagonisté a inhibitory MeSH
- lidé MeSH
- molekulární struktura MeSH
- molekuly buněčné adheze * metabolismus antagonisté a inhibitory MeSH
- receptory buněčného povrchu * metabolismus antagonisté a inhibitory MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Recent advances in optical sensing technologies underpin the development of high-performance, surface-sensitive analytical tools capable of reliable and precise detection of molecular targets in complex biological media in non-laboratory settings. Optical fibre sensors guide light to and from a region of interest, enabling sensitive measurements of localized environments. This positions optical fibre sensors as a highly promising technology for a wide range of biochemical and healthcare applications. However, their performance in real-world biological media is often limited by the absence of robust post-modification strategies that provide both high biorecognition and antifouling capabilities. In this study, we present the proof-of-concept antifouling and biorecognition performance of a polymer brush nano-coating synthesized at the sensing region of optical fibre long-period grating (LPG) sensors. Using a newly developed antifouling terpolymer brush (ATB) composed of carboxybetaine methacrylamide, sulfobetaine methacrylamide, and N-(2-hydroxypropyl)methacrylamide, we achieve state-of-the-art antifouling properties. The successful on-fibre ATB synthesis is confirmed through scanning electron microscopy (SEM), fluorescence microscopy, and label-free bio-detection experiments based on antibody-functionalized ATB-coated LPG optical fibres. Despite the challenges in handling optical fibres during polymerization, the resulting nano-coating retains its remarkable antifouling properties upon exposure to blood plasma and enables biorecognition element functionalization. These capabilities are demonstrated through the detection of IgG in buffer and diluted blood plasma using anti-IgG-functionalized ATB-coated sensing regions of LPG fibres in both label-based (fluorescence) and label-free real-time detection experiments. The results show the potential of ATB-coated LPG fibres for use in analytical biosensing applications.
Public transport represents a potential site for the transmission of resistant pathogens due to the rapid movement of large numbers of people. This study aimed to investigate the bacterial contamination of frequently touched surfaces in the public transport system operating in the proximity of the biggest Czech hospital during the coronavirus pandemic despite extensive cleaning and disinfection efforts. In June and September 2020, samples from the metro trains, ground transport and stationary objects were collected, enriched and cultured. The antimicrobial susceptibility was tested by broth microdilution. Staphylococcus aureus isolates exhibiting inconclusive results of vancomycin susceptibility testing were retested by broth macrodilution and subjected to whole genome sequencing. All S. aureus isolates were tested for vancomycin heteroresistance (hVISA). A total of 513/542 (94.6 %) samples were culture-positive with higher frequency in September (p = 0.004). S. aureus was the most frequent opportunistic bacterial pathogen found (3.7 %, 20/542) followed by Enterobacterales spp. (1.8 %, 10/542). No methicillin-resistant S. aureus (MRSA), extended-spectrum beta-lactamase producers (ESBL) or carbapenemase-producing bacteria were detected. Resistance to clinically relevant drugs was rare except for resistance to ampicillin (67 %, 8/12), cefuroxime (42 %, 5/12) in Enterobacterales and chloramphenicol (90 %, 18/20), penicillin (45 %, 9/20), and erythromycin (20 %, 4/20) in S. aureus. One S. aureus isolate was shown to be resistant to vancomycin (8 mg/L) by forming large visible cell aggregates. Population analysis profile-area under the curve ratio (PAP-AUC) testing did not confirm the hVISA phenotype, but mutations in the hVISA phenotype-related gene vraR and other genes related to cell wall synthesis (fmtB) and intercellular adhesion (sasC) were found. Our study shows that in the COVID-19 pandemic, despite the intensive use of disinfectants, public transport was a source of opportunistic bacterial pathogens including S. aureus with unusual vancomycin resistance phenotype that could be easily missed by standard susceptibility testing.
- MeSH
- antibakteriální látky * farmakologie MeSH
- COVID-19 * MeSH
- doprava MeSH
- lidé MeSH
- mikrobiální testy citlivosti * MeSH
- pandemie MeSH
- rezistence na vankomycin MeSH
- SARS-CoV-2 * MeSH
- Staphylococcus aureus * účinky léků genetika MeSH
- vankomycin * farmakologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
Mikroorganismy si během evoluce vyvinuly širokou škálu strategií, jak uniknout vrozenému i adaptivnímu imunitnímu systému, a některým těmto strategiím se věnujeme v našem přehledu. Mikroorganismy mohou využívat podobnost svých proteinů s proteiny hostitele, produkovat protizánětlivé faktory, narušovat komplementový systém, ovlivňovat funkci a blokovat syntézu cytokinů, inhibovat rozpoznávání imunoglobulinů, snižovat expresi a modifikovat antigeny na svém povrchu, narušovat zpracování a prezentaci antigenu imunitními buňkami, vstupovat do imunitních buněk, ovlivňovat apoptózu buněk, modulovat funkce imunitních buněk nebo ovlivňovat produkci hormonů. S těmito únikovými strategiemi je nutné počítat při léčbě infekčních onemocnění.
Microorganisms have evolved a wide variety of strategies to evade both the innate and adaptive immune systems during evolution, and some of these strategies are addressed in our review. Microorganisms can use the similarity of their proteins to host proteins, produce anti-inflammatory factors, disrupt the complement system, affect the function and block the synthesis of cytokines, inhibit the recognition of immunoglobulins, reduce the expression and modify antigens on their surface, disrupt the processing and presentation of antigen by immune cells, enter immune cells , influence cell apoptosis, modulate immune cell functions or influence hormone production. These escape strategies must be taken into account when treating infectious diseases.
- Klíčová slova
- únikové strategie mikroorganismů,
- MeSH
- interakce hostitele a patogenu MeSH
- lidé MeSH
- mikrobiologické jevy * MeSH
- přirozená imunita * MeSH
- trénovaná imunita MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přehledy MeSH
Mitochondrial oxidative phosphorylation (OXPHOS) fuels cellular ATP demands. OXPHOS defects lead to severe human disorders with unexplained tissue specific pathologies. Mitochondrial gene expression is essential for OXPHOS biogenesis since core subunits of the complexes are mitochondrial-encoded. COX14 is required for translation of COX1, the central mitochondrial-encoded subunit of complex IV. Here we describe a COX14 mutant mouse corresponding to a patient with complex IV deficiency. COX14M19I mice display broad tissue-specific pathologies. A hallmark phenotype is severe liver inflammation linked to release of mitochondrial RNA into the cytosol sensed by RIG-1 pathway. We find that mitochondrial RNA release is triggered by increased reactive oxygen species production in the deficiency of complex IV. Additionally, we describe a COA3Y72C mouse, affected in an assembly factor that cooperates with COX14 in early COX1 biogenesis, which displays a similar yet milder inflammatory phenotype. Our study provides insight into a link between defective mitochondrial gene expression and tissue-specific inflammation.
- MeSH
- cyklooxygenasa 1 * MeSH
- DEAD box protein 58 MeSH
- DEAD-box RNA-helikasy metabolismus genetika MeSH
- játra * metabolismus patologie MeSH
- lidé MeSH
- membránové proteiny MeSH
- mitochondriální proteiny metabolismus genetika MeSH
- mitochondrie metabolismus MeSH
- mutace MeSH
- myši inbrední C57BL MeSH
- myši MeSH
- oxidativní fosforylace * MeSH
- proteosyntéza MeSH
- reaktivní formy kyslíku * metabolismus MeSH
- respirační komplex IV * metabolismus genetika MeSH
- RNA mitochondriální genetika metabolismus MeSH
- zánět * metabolismus genetika patologie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Moderní medicína klade velký důraz nejen na účinnost, ale zejména na bezpečnost léčby. Společným nedostatkem antikoagulancií blokujících společnou cestu koagulační kaskády (inhibitorů trombinu, inhibitorů faktoru Xa či antivitaminů K) je zvýšené riziko klinicky významného krvácení. Přichází nová strategie zaměřená na inhibici vnitřní cesty koagulační kaskády, konkrétně na inhibici syntézy či blokádu funkce faktoru XI/XIa. Tato cesta je slibná, neboť k nejčastějším indikacím antikoagulancií patří aktivace hemostázy kontaktem (navozená např. polyfosfáty na povrchu aktivovaných trombocytů či kontaktem s negativním elektrostatickým povrchem) či reparačně-zánětlivými pochody (zejm. vlákny extracelulárně uvolněné DNA z neutrofilních leukocytů – NET či řadou cytokinů). Podmínkou aktivace této vnitřní cesty koagulace je stagnace krve umožňující dosažení účinné lokální koncentrace enzymů koagulační kaskády. Těmto podmínkám odpovídají dvě nejčastější indikace antikoagulační léčby – prevence tromboembolických příhod provázejících fibrilaci síní či profylaxe a léčba tromboembolické nemoci. Zachování aktivní vnější cesty koagulace pak umožní zachování hemostázy při poškození cévní stěny, tedy např. při poškození sliznic, při úrazech či operačních zákrocích. Typy léčiv prověřované při inhibici faktoru XI/XIa demonstrují současný posun možností farmakologické intervence. Vedle klasických léčiv s malou molekulou (např. asundexian, milvexian) jsou vyvíjeny monoklonální protilátky (např. abelacimab, osocimab) či inhibující oligonukleotidy (např. fesomersen). Řada těchto léčiv má ukončeny časné fáze klinického hodnocení a v řadě indikací (profylaxe tromboembolické nemoci po ortopedických zákrocích, v rámci prevence tromboembolických příhod při fibrilaci síní či v indikaci sekundární prevence po infarktu myokardu či iktu) probíhají poslední předregistrační fáze hodnocení.
Modern medicine places great emphasis not only on the efficacy but especially on the safety of the treatment. A common deficiency of anticoagulants inhibitingg the common pathway of the coagulation cascade (thrombin inhibitors, factor Xa inhibitors or antivitamins K) is an increased risk of clinically significant bleeding. A new strategy is being developed to inhibit the intrinsic pathway of the coagulation cascade, specifically to inhibit the synthesis or block the function of factor XI/XIa. This route is promising, as the most common indications of anticoagulants include activation of haemostasis by contact (induced e.g. by polyphosphates on the surface of activated platelets or by contact with a negative electrostatic surface) or by repair-inflammatory processes (especially by extracellularly released DNA fibres from neutrophilic leukocytes - NETs or by a number of cytokines). The condition for the activation of this intrinsic coagulation pathway is the stagnation of the blood, allowing the achievement of an effective local concentration of enzymes of the coagulation cascade. These conditions correspond to the two most common indications for anticoagulant therapy - prevention of thromboembolic events accompanying atrial fibrillation or prophylaxis and treatment of thromboembolic disease. Maintaining an active external coagulation pathway will then allow for the preservation of hemostasis in the event of damage to the vascular wall, e.g. damage to mucous membranes, injuries or surgeries. The types of drugs investigated in inhibition of factor XI/XIa demonstrate the current shift in pharmacological intervention options. In addition to classical small molecule drugs (e.g. asundexian, milvexian), monoclonal antibodies (e.g. abelacimab, osocimab) or oligonucleotide inhibitors (e.g. fesomersen) are being developed. A number of these drugs have completed the early phases of clinical trials, and in a number of indications (prophylaxis of thromboembolic disease after orthopaedic procedures, as part of the prevention of thromboembolic events in atrial fibrillation or in the indication of secondary prevention after myocardial infarction or stroke), the last preregistration phases of the trial are underway.
- MeSH
- antikoagulancia * aplikace a dávkování farmakologie terapeutické užití MeSH
- faktor IX antagonisté a inhibitory MeSH
- faktor IXa antagonisté a inhibitory MeSH
- hemokoagulace účinky léků MeSH
- hemostáza MeSH
- inhibitory koagulačních faktorů aplikace a dávkování terapeutické užití MeSH
- kardiovaskulární nemoci prevence a kontrola MeSH
- lidé MeSH
- Check Tag
- lidé MeSH
Dolichol is a lipid critical for N-glycosylation as a carrier for activated sugars and nascent oligosaccharides. It is commonly thought to be directly produced from polyprenol by the enzyme SRD5A3. Instead, we found that dolichol synthesis requires a three-step detour involving additional metabolites, where SRD5A3 catalyzes only the second reaction. The first and third steps are performed by DHRSX, whose gene resides on the pseudoautosomal regions of the X and Y chromosomes. Accordingly, we report a pseudoautosomal-recessive disease presenting as a congenital disorder of glycosylation in patients with missense variants in DHRSX (DHRSX-CDG). Of note, DHRSX has a unique dual substrate and cofactor specificity, allowing it to act as a NAD+-dependent dehydrogenase and as a NADPH-dependent reductase in two non-consecutive steps. Thus, our work reveals unexpected complexity in the terminal steps of dolichol biosynthesis. Furthermore, we provide insights into the mechanism by which dolichol metabolism defects contribute to disease.
- MeSH
- 3-oxo-5-alfa-steroid-4-dehydrogenasa metabolismus genetika MeSH
- dolichol * metabolismus biosyntéza MeSH
- glykosylace MeSH
- lidé MeSH
- membránové proteiny metabolismus genetika MeSH
- missense mutace MeSH
- vrozené poruchy glykosylace metabolismus genetika MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
ORMDL3 is a prominent member of a family of highly conserved endoplasmic reticulum resident proteins, ORMs (ORM1 and ORM2) in yeast, dORMDL in Drosophila and ORMDLs (ORMDL1, ORMDL2, and ORMDL3) in mammals. ORMDL3 mediates feedback inhibition of de novo sphingolipid synthesis. Expression levels of ORMDL3 are associated with the development of inflammatory and autoimmune diseases including asthma, systemic lupus erythematosus, type 1 diabetes mellitus and others. It has been shown that simultaneous deletions of other ORMDL family members could potentiate ORMDL3-induced phenotypes. To understand the complex function of ORMDL proteins in immunity in vivo, we analyzed mice with single or double deletions of Ormdl genes. In contrast to other single and double knockouts, simultaneous deletion of ORMDL1 and ORMDL3 proteins disrupted blood homeostasis and reduced immune cell content in peripheral blood and spleens of mice. The reduced number of splenocytes was not caused by aberrant immune cell homing. A competitive bone marrow transplantation assay showed that the development of Ormdl1-/-/Ormdl3-/- B cells was dependent on lymphocyte intrinsic factors. Highly increased sphingolipid production was observed in the spleens and bone marrow of Ormdl1-/-/Ormdl3-/- mice. Slight, yet significant, increase in some sphingolipid species was also observed in the spleens of Ormdl3-/- mice and in the bone marrow of both, Ormdl1-/- and Ormdl3-/- single knockout mice. Taken together, our results demonstrate that the physiological expression of ORMDL proteins is critical for the proper development and circulation of lymphocytes. We also show cell-type specific roles of individual ORMDL family members in the production of different sphingolipid species.
- MeSH
- B-lymfocyty imunologie metabolismus MeSH
- delece genu * MeSH
- homeostáza * MeSH
- membránové proteiny * genetika metabolismus MeSH
- myši inbrední C57BL MeSH
- myši knockoutované MeSH
- myši MeSH
- sfingolipidy metabolismus MeSH
- slezina imunologie metabolismus MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
AIM: Cutaneous T-cell lymphomas (CTCL) can be described as chronic skin inflammation lesions with the content of malignant T cells and they are considered to be T-cell-mediated skin diseases. CD147 is recognized as a 58-kDa cell surface glycoprotein of the immunoglobulin superfamily; it can induce the synthesis of MMPs (matrix metalloproteinases) on the surface of tumor cells where it was originally identified. It can also function in adjacent tumor fibroblasts using CD147-CD147 interactions. The polymorphism rs8259 T/A is situated in the untranslated region (3'UTR) of the CD147 gene. HLA DRB1*1501 takes part in the process of presentation and recognition of different antigens to T cells. It can be expressed by antigen-presenting cells-macrophages, dendritic cells, and B cells. The aim of the study is to test genotype-phenotype associations of both polymorphisms including therapy in a large cohort of CTCL patients. MATERIALS AND METHODS: A final total of 104 CTCL patients were enrolled in the study. For the first remission at the clinic department, they were treated by means of local skin-directed therapy, phototherapy, and systemic therapy. Genomic DNA was isolated from peripheral blood leukocytes. A standard technique using proteinase K was applied. The polymorphisms rs8259 T/A (CD147 gene) and rs3135388 (HLA DRB1*1501) were detected through standard PCR-restriction fragment length polymorphism methods. RESULTS: The severity of the disease (patients with parapsoriasis, stages IA and IB, vs patients with stages IIB, IIIA, and IIIB) was associated with the CD147 genotype: the AA variant was 3.38 times more frequent in more severe cases, which reflects the decision on systemic therapy (p = 0.02, specificity 0.965). The AA genotype in the CD147 polymorphism was 12 times more frequent in patients who underwent systemic therapy of CTCL compared to those not treated with this therapy (p = 0.009, specificity 0.976). The same genotype was also associated with radiotherapy-it was observed 14 times more frequently in patients treated with radiotherapy (p = 0.009, specificity 0.959). In patients treated with interferon α therapy, the AA genotype was observed to be 5.85 times more frequent compared to the patients not treated with interferon therapy (p = 0.03, specificity 0.963). The HLA DRB1*1501 polymorphism was associated with local skin-directed therapy of CTCL. The CC genotype of the polymorphism was observed to be 3.57 times more frequent in patients treated with local therapy (p = 0.008, specificity 0.948). When both polymorphisms had been calculated together, even better results were obtained: the AACC double genotype was 11 times more frequent in patients with severe CTCL (p = 0.009, specificity 0.977). The TACT double genotype was associated with local skin-directed therapy (0.09 times lower frequency, p = 0.007, sensitivity 0.982). The AACC genotype was 8.9 times more frequent in patients treated by means of systemic therapy (p = 0.02, specificity 0.976) and as many as 18.8 times more frequent in patients treated with radiotherapy (p = 0.005, specificity 0.969). Thus, the AACC double genotype of CD147 and DRB1*1501 polymorphisms seems to be a clinically highly specific marker of severity, systemic therapy and radiotherapy of patients with T-cell lymphoma. CONCLUSION: Although genotyping results were not known during the treatment decision and could not modify it, the clinical decision on severity and therapy reflected some aspects of the genetic background of this complicated T-cell-associated disease very well.
- MeSH
- genetické markery MeSH
- HLA-DRB1 řetězec genetika MeSH
- kožní T-buněčný lymfom * farmakoterapie genetika MeSH
- lidé MeSH
- lymfom T-buněčný * MeSH
- nádory kůže * farmakoterapie genetika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH