N-Methyl-d-aspartate receptors (NMDARs) play a crucial role in excitatory neurotransmission, with numerous pathogenic variants identified in the GluN subunits, including their ligand-binding domains (LBDs). The prevailing hypothesis postulates that the endoplasmic reticulum (ER) quality control machinery verifies the agonist occupancy of NMDARs, but this was tested in a limited number of studies. Using microscopy and electrophysiology in the human embryonic kidney 293 (HEK293) cells, we found that surface expression of GluN1/GluN2A receptors containing a set of alanine substitutions within the LBDs correlated with the measured EC50 values for glycine (GluN1 subunit mutations) while not correlating with the measured EC50 values for l-glutamate (GluN2A subunit mutations). The mutant cycle of GluN1-S688 residue, including the pathogenic GluN1-S688Y and GluN1-S688P variants, showed a correlation between relative surface expression of the GluN1/GluN2A receptors and the measured EC50 values for glycine, as well as with the calculated ΔGbinding values for glycine obtained from molecular dynamics simulations. In contrast, the mutant cycle of GluN2A-S511 residue did not show any correlation between the relative surface expression of the GluN1/GluN2A receptors and the measured EC50 values for l-glutamate or calculated ΔGbinding values for l-glutamate. Coexpression of both mutated GluN1 and GluN2A subunits led to additive or synergistic alterations in the surface number of GluN1/GluN2A receptors. The synchronized ER release by ARIAD technology confirmed the altered early trafficking of GluN1/GluN2A receptors containing the mutated LBDs. The microscopical analysis from embryonal rat hippocampal neurons (both sexes) corroborated our conclusions from the HEK293 cells.
- MeSH
- Glycine metabolism MeSH
- HEK293 Cells MeSH
- Hippocampus cytology metabolism MeSH
- Rats MeSH
- Glutamic Acid metabolism MeSH
- Humans MeSH
- Ligands MeSH
- Mutation genetics MeSH
- Protein Domains MeSH
- Nerve Tissue Proteins MeSH
- Receptors, N-Methyl-D-Aspartate * metabolism genetics chemistry MeSH
- Protein Transport physiology genetics MeSH
- Animals MeSH
- Check Tag
- Rats MeSH
- Humans MeSH
- Male MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
BACKGROUND: The treatment of non-small cell lung cancer (NSCLC) patients is correlated with the efficacy of immune checkpoint blockade therapy (ICB) targeting programmed cell death ligand 1 (PD-L1) or its cognate receptor (PD-1) on cancer cells or infiltrating immune cells. Analysis of PD-L1/PD-1 expression in tumor tissue represents a crucial step before PD-L1/PD-1 blocker usage. METHODS: We used directed evolution of protein variants derived from a 13 kDa Myomedin loop-type combinatorial library with 12 randomized amino acid residues to select high-affinity binders of human PD-L1 (hPD-L1). After the ribosome display, individual clones were screened by ELISA. Detailed analysis of binding affinity and kinetics was performed using LigandTracer. The specificity of Myomedins was assessed using fluorescent microscopy on HEK293T-transfected cells and cultured cancer cells in vitro, formalin-fixed paraffin-embedded (FFPE) sections of human tonsils, and FFPE tumor samples of NSCLC patients. RESULTS: Seven identified PD-L1 binders, called MLE, showed positive staining for hPD-L1 on transfected HEK293T cells and cultured MCF-7 cells. MLE031, MLE105, MLE249, and MLE309 exhibited high affinity to both human and mouse PD-L1-transfected HEK293T cells measured with LigandTracer. The diagnostic potential of MLE variants was tested on human tonsillitis tissue and compared with diagnostic anti-PD-L1 antibody DAKO 28-8 and PD-L1 IHC 22C3 pharmDx antibody. MLE249 and MLE309 exhibited an excellent overlap with diagnostic DAKO 28-8 (Pearson ́s coefficient (r) = 0.836 and 0.731, respectively) on human tonsils on which MLE309 exhibited also excellent overlap with diagnostic 22C3 antibody (r = 0.876). Using three NSCLC tissues, MLE249 staining overlaps with 28-8 antibody (r = 0.455-0.883), and MLE309 exhibited overlap with 22C3 antibody (r = 0.534-0.619). Three MLE proteins fused with Fc fragments of rabbit IgG, MLE249-rFc, MLE309-rFc and MLE031-rFc, exhibited very good overlap with anti-PD-L1 antibody 28-8 on tonsil tissue (r = 0.691, 0.610, and 0.667, respectively). Finally, MLE249-rFc, MLE309-rFc and MLE031-rFc exhibited higher sensitivity in comparison to IHC 22C3 antibody using routine immunohistochemistry staining system Ventana, which is one of gold standards for PD-L1 diagnosis. CONCLUSIONS: We demonstrated the development of MLE Myomedins specifically recognizing hPD-L1 that may serve as a refinement tool for clinical PD-L1 detection.
Tumor suppressor p53 is a key player in the cell response to DNA damage that suffers by frequent inactivating aberrations. Some of them disturb p53 oligomerization and influence cell decision between proliferation, growth arrest and apoptosis. Active p53 resides mostly in the nucleus, degradation occurs in the cytoplasm. Acute myeloid leukemia (AML)-related mutation of NPM (NPMmut) induces massive mislocalization of p53 to the cytoplasm, which might be related to leukemia initiation. Since both proteins interact and execute their function as oligomers, we investigated the role of perturbed p53 oligomerization in the p53 mislocalization process in live cells by FLIM (fluorescence lifetime imaging microscopy), fluorescence anisotropy imaging (FAIM), fluorescence cross-correlation spectroscopy (FCCS) and immunochemical methods. On a set of fluorescently labeled p53 variants, monomeric R337G and L344P, dimeric L344A, and multimeric D352G and A353S, we correlated their cellular localization, oligomerization and interaction with NPMmut. Interplay between nuclear export signal (NES) and nuclear localization signal (NLS) of p53 was investigated as well. While NLS was found critical for the nuclear p53 localization, NES plays less significant role. We observed cytoplasmic translocation only for multimeric A353S variant with sufficient stability and strong interaction with NPMmut. Less stable multimer D352G and L344A dimer were not translocated, monomeric p53 variants always resided in the nucleus independently of the presence of NPMmut and NES intactness. Oligomeric state of NPMmut is not required for p53 translocation, which happens also in the presence of the nonoligomerizing NPMmut variant. The prominent structural and functional role of the R337 residue is shown.
- MeSH
- Leukemia, Myeloid, Acute * genetics metabolism MeSH
- Cell Nucleus metabolism MeSH
- Cytoplasm metabolism MeSH
- Nuclear Localization Signals metabolism MeSH
- Nuclear Proteins * genetics metabolism MeSH
- Humans MeSH
- Protein Multimerization MeSH
- Mutation * MeSH
- Cell Line, Tumor MeSH
- Tumor Suppressor Protein p53 * metabolism genetics chemistry MeSH
- Nucleophosmin MeSH
- Nuclear Export Signals MeSH
- Protein Transport MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
Despite the significance of neck muscles in musculoskeletal disorders, their microscopic anatomy remains poorly characterized. This study examined the splenius capitis muscle, focusing on its fiber-type composition, fiber size, and capillary network characteristics. For comparison and validation, the vastus lateralis muscle was also analyzed. Muscle samples from 13 young male subjects (mean age ± SD: 35.7 ± 8.6 years) were collected within 24-h post-mortem during autopsy. Myosin heavy chain (MyHC) isoform expression was characterized immunohistochemically in 10 μm sections, while the capillary network architecture was assessed in 100 μm sections. Immunofluorescence staining, confocal microscopy, and 3D image analysis were employed to quantify capillary tortuosity, anisotropy, branch density (Br dens), and the length of capillaries per muscle volume (LV), per muscle fiber length (LL), per fiber surface area (LS), and per fiber volume (LVf). Compared to the vastus lateralis muscle, the splenius capitis muscle had a higher percentage of type 1 fibers (51.2% vs 39.7%), fewer type 2a fibers (16.2% vs 31.4%), and smaller fiber diameters (35.5-40.9 μm vs 47-56.1 μm). It also displayed lower Br dens (P = 0.0069), higher anisotropy (P = 0.0004), and lower LL (P < 0.0001) but higher LVf (P = 0.0486). In the splenius capitis muscle, body mass index (BMI) negatively correlated with LV (P = 0.0155), LS (P = 0.0091), LVf (P = 0.0137), and anisotropy (P = 0.0425), and positively correlated with tortuosity (P = 0.0473), indicating a reduction in the capillary network. In the vastus lateralis muscle, only LV (P = 0.0161) decreased with high BMI. This study characterized the fiber-type composition, fiber size, and 3D capillary network of the splenius capitis muscle, establishing a baseline for investigations into pathological muscle alterations.
Cyanobacterial harmful blooms (CyanoHABs) pose a global ecological problem, and their lipopolysaccharides (LPS) are among the bioactive compounds they release. Previous studies on CyanoHAB-LPS from single cyanobacterial species have shown varying bioactivities in different in vitro cell models. In this study, we isolated LPS from 19 CyanoHAB samples collected at 18 water bodies in the Czech Republic over two consecutive seasons. The proportions of cyanobacteria, Gram-negative bacteria (G-), and other bacteria in the biomass were determined by qPCR, while the cyanobacterial genera were identified using light microscopy. In vitro models of keratinocytes (HaCaT), the intestinal epithelium (co-culture of differentiated Caco-2 cells and peripheral blood mononuclear cells - PBMC), and PBMC alone were treated with isolated LPS at concentrations of 50, 100, and 1 μg/ml, respectively. The endotoxin activities of these concentrations were within the range measured in the aquatic environment. Approximately 85-90% of the samples displayed biological activity. However, the potency of individual LPS effects and response patterns varied across the different in vitro models. Furthermore, the observed activities did not exhibit a clear correlation with the taxonomic composition of the phytoplankton community, the relative share of microbial groups in the biomass, endotoxin activity of the LPS, or LPS migration and staining pattern in SDS-PAGE. These findings suggest that the effects of CyanoHAB-LPS depend on the specific composition and abundance of various LPS structures within the complex environmental sample and their interactions with cellular receptors.
- MeSH
- Biomass MeSH
- Caco-2 Cells MeSH
- Leukocytes, Mononuclear MeSH
- Humans MeSH
- Lipopolysaccharides * toxicity MeSH
- Cyanobacteria * MeSH
- Harmful Algal Bloom MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
Pneumocystis pneumonia (PCP) is a life-threatening complication after allogeneic hematopoietic cell transplantation (allo-HCT). However, allo-HCT procedures have evolved toward older patients, unrelated donors, and reduced-intensity conditioning, possibly modifying the risks. Polymerase chain reaction (PCR), widely used nowadays, is more sensitive than microscopy diagnostic methods. This study aimed to assess the factors associated with PCP in allo-HCT recipients within 2 years of HCT and managed according to current procedures. This multicenter, nested case-control study included PCP cases diagnosed by PCR, cytology, or immunofluorescence on bronchoalveolar lavage fluid between 2016 and 2018. Two controls per case were selected from the ProMISe registry and matched for the center, transplant date, and underlying disease. Fifty-two cases and 104 controls were included among the 5452 patients who underwent allo-HCT in the participating centers. PCP occurred at a median of 11.5 months after transplantation. The mortality rate was 24% on day 30 after the PCP diagnosis and 37% on day 90. The clinical presentation and mortality rates of the 24 patients diagnosed using only PCR were not different from those diagnosed with microscopy methods. Our study demonstrates a substantial incidence of, and mortality from, PCP, after allogeneic HCT despite well-established prophylactic approaches. In our experience, PCP nowadays occurs later after transplant than previously reported, justifying the prolongation of prophylaxis after six months in many cases. Allo-HCT recipients diagnosed with PCR as the only PCP marker should benefit from specific treatment as for other patients.
- MeSH
- Communicable Diseases * etiology MeSH
- Bone Marrow MeSH
- Humans MeSH
- Pneumonia, Pneumocystis * epidemiology etiology diagnosis MeSH
- Risk Factors MeSH
- Case-Control Studies MeSH
- Hematopoietic Stem Cell Transplantation * adverse effects methods MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Multicenter Study MeSH
Bazocelulárny karcinóm je najčastejší typ rakoviny kože a zároveň najčastejšia forma malignity vôbec. Vzhľadom na významnú heterogenitu závažnosti bazocelulárneho karcinómu ale aj širokú škálu dostupných liečebných modalít je efektívna subtypizácia kľúčová pre optimalizáciu terapeutického plánovania. Z hľadiska diagnostickej výťažnosti dermatoskopie pri subtypizácii bazocelulárneho karcinómu výsledky viacerých štúdií nasvedčujú, že ide o spoľahlivú metódu, čo je reflektované aj v odporúčaniach významných odborných spoločností. Dermatoskopické hodnotenie nadobúda význam najmä pri voľbe nechirurgických liečebných modalít ako aj pri selekcii nádorov, ktoré je nevyhnutné ďalej verifikovať histopatologicky. Cieľom príspevku bolo stručne zhrnúť praktické aspekty hodnotenia nádoru z hľadiska stratifikácie rizika, a to na klinickej aj dermatoskopickej úrovni. V oblasti lokálnej liečby bazocelulárneho karcinómu prebieha v súčasnosti rozsiahly výskum, a preto je pravdepodobné, že hodnotenie za použitia neinvazívnych diagnostických modalít nadobudne v budúcnosti ešte väčší význam ako doposiaľ.
Basal cell carcinoma is the most common type of skin cancer and also the most common form of malignancy overall. Given the significant heterogeneity in the severity of basal cell carcinoma as well as the wide range of available treatment modalities, effective subtyping is crucial for optimizing therapeutic planning. In terms of the diagnostic yield of dermoscopy for the subtyping of basal cell carcinoma, results from several studies suggest its reliability, which is reflected in the guidelines of most professional societies.Dermoscopic evaluation becomes particularly important when choosing non-surgical treatment modalities as well as in the selection of tumors that require further histopathological verification. The aim of this article was to briefly summarize the practical aspects of tumor evaluation in terms of risk stratification at both the clinical and dermoscopic level. With extensive research ongoing in local treatments, non-invasive diagnostic tools are poised to play an even greater role in the future.
- MeSH
- Carcinoma, Basal Cell * diagnostic imaging classification ultrastructure MeSH
- Dermoscopy MeSH
- Humans MeSH
- Risk Factors MeSH
- Check Tag
- Humans MeSH
- Publication type
- Review MeSH
Plasmonic photothermal therapy (PPTT) employing plasmonic gold nanorods (GNRs) presents a potent strategy for eradication of tumors including aggressive brain gliomas. Despite its promise, there is a pressing need for a more comprehensive evaluation of PPTT using sophisticated in vitro models that closely resemble tumor tissues, thereby facilitating the elucidation of therapeutic mechanisms. In this study, we exposed 3D glioma spheroids (tumoroids) to (16-mercaptohexadecyl)trimethylammonium bromide-functionalized gold nanorods (MTAB-GNRs) and a near-infrared (NIR) laser. We demonstrate that the photothermal effect can be fine-tuned by adjusting the nanoparticle concentration and laser power. Depending on the selected parameters, the laser can trigger either regulated or non-regulated cell death (necrosis) in both mouse GL261 and human U-87 MG glioma cell lines, accompanied by translocation of phosphatidylserine in the membrane. Our investigation into the mechanism of regulated cell death induced by PPTT revealed an absence of markers associated with classical apoptosis pathways, such as cleaved caspase 3. Instead, we observed the presence of cleaved caspase 1, gasdermin D, and elevated levels of NLRP3 in NIR-irradiated tumoroids, indicating the activation of pyroptosis. This finding correlates with previous observations of lysosomal accumulation of MTAB-GNRs and the known lysosomal pathway of pyroptosis activation. We further confirmed the absence of toxic breakdown products of GNRs using electron microscopy, which showed no melting or fragmentation of gold nanoparticles under the conditions causing regulated cell death. In conclusion, PPTT using coated gold nanorods offers significant potential for glioma cell elimination occurring through the activation of pyroptosis rather than classical apoptosis pathways.
- MeSH
- Spheroids, Cellular drug effects pathology MeSH
- Photothermal Therapy MeSH
- Glioma * pathology drug therapy metabolism MeSH
- Cations chemistry pharmacology MeSH
- Metal Nanoparticles chemistry MeSH
- Quaternary Ammonium Compounds chemistry pharmacology MeSH
- Humans MeSH
- Mice MeSH
- Cell Line, Tumor MeSH
- Tumor Cells, Cultured MeSH
- Nanotubes * chemistry MeSH
- Pyroptosis * drug effects MeSH
- Cell Survival drug effects MeSH
- Gold * chemistry pharmacology MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Mice MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
BACKGROUND: Chemical modifications in mRNAs, tRNAs, rRNAs, and non-coding RNAs stabilize these nucleic acids and regulate their function. In addition to regulating the translation of genetic information from mRNA to proteins, it has been revealed that modifications in RNAs regulate repair processes in the genome. METHODS: Using local laser microirradiation, confocal microscopy, dot blots, and mass spectrometry we studied the role of N7-methylguanosine (m7G), which is co-transcriptionally installed in RNA. RESULTS: Here, we show that after UVC and UVA irradiation, the level of m7G RNA is increased initially in the cytoplasm, and after local laser microirradiation, m7G RNA is highly abundant in UVA-damaged chromatin. This process is poly(ADP-ribose) polymerase (PARP)-dependent, but not accompanied by changes in the level of m7G-writers, including methyltransferases RNMT, METTL1, and WBSCR22. We also observed that METTL1 deficiency does not affect the recruitment of m7G RNA to microirradiated chromatin. Analyzing the levels of mRNA, let-7e, and miR-203a in both the cytoplasm and the cell nucleus, we revealed that UVC irradiation changed the level of mRNA, and significantly increased the pool of both let-7e and miR-203a, which correlated with radiation-induced m7G RNA increase in the cytoplasm. CONCLUSIONS: Irradiation by UV light increases the m7G RNA pool in the cytoplasm and in the microirradiated genome. Thus, epigenetically modified RNAslikely contribute to DNA damage responses or m7G signals the presence of RNA damage.
- Publication type
- Journal Article MeSH
Preterm, prelabor rupture of the human fetal membranes (pPROM) is involved in 40% of spontaneous preterm births worldwide. Cellular-level disturbances and inflammation are effectors of membrane degradation, weakening, and rupture. Maternal risk factors induce oxidative stress (OS), senescence, and senescence-associated inflammation of the fetal membranes as reported mechanisms related to pPROM. Inflammation can also arise in fetal membrane cells (amnion/chorion) due to OS-induced autophagy and epithelial-mesenchymal transition (EMT). Autophagy, EMT, and their correlation in pPROM, along with OS-induced autophagy-related changes in amnion and chorion cells in vitro, were investigated. Immunocytochemistry staining of cytokeratin-18 (epithelial marker)/vimentin (mesenchymal marker) and proautophagy-inducing factor LC3B were performed in fetal membranes from pPROM, term not in labor, and term labor. Ultrastructural changes associated with autophagy were verified by transmission electron microscopy of the fetal membranes and in cells exposed to cigarette smoke extract (an OS inducer). EMT and LC3B staining was compared in the chorion from pPROM versus term not in labor. Transmission electron microscopy confirmed autophagosome formation in pPROM amnion and chorion. In cell culture, autophagosomes were formed in the amnion with OS treatment, while autophagosomes were accumulated in both cell types with autophagy inhibition. This study documents the association between pPROMs and amniochorion autophagy and EMT, and supports a role for OS in inducing dysfunctional cells that increase inflammation, predisposing membranes to rupture.
- MeSH
- Autophagy MeSH
- Epithelial-Mesenchymal Transition MeSH
- Extraembryonic Membranes * metabolism MeSH
- Humans MeSH
- Infant, Newborn MeSH
- Fetal Membranes, Premature Rupture * metabolism MeSH
- Inflammation pathology MeSH
- Check Tag
- Humans MeSH
- Infant, Newborn MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
