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1.
Int J Biol Macromol ; : 133692, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38972657

RESUMEN

Bombus terrestris are efficient pollinators in forestry and agriculture, with higher cold tolerance than other bees. Yet, their cold tolerance mechanism remains unclear. Aquaporins (AQPs) function as cell membrane proteins facilitating rapid water flow, aiding in osmoregulation. Recent studies highlight the importance of insect AQPs in dehydration and cold stress. Comparative transcriptome analysis of B. terrestris under cold stress revealed up-regulation of four AQPs, indicating their potential role in cold tolerance. Seven AQPs-Eglp1, Eglp2, Eglp3, DRIP, PRIP, Bib, and AQP12L-have been identified in B. terrestris. These are widely expressed in various tissues, particularly in the alimentary canal and Malpighian tubules. Functional analysis of BterAQPs in the Xenopus laevis oocytes expressing system showed distinct water and glycerol selectivity, with BterDrip exhibiting the highest water permeability. Molecular modeling of BterDrip revealed six transmembrane domains, two NPA motifs, and an ar/R constriction region (Phe131, His256, Ser265, and Arg271), likely contributing to its water selectivity. Silencing BterDRIP accelerated mortality in B. terrestris under cold stress, highlighting the crucial role of BterDRIP in their cold tolerance and providing a molecular mechanism for their cold adaptation.

2.
J Invest Dermatol ; 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38960086

RESUMEN

Exudates of non-healing wounds contain drivers of pathogenicity. We utilized >800 exudates from non-healing and healing wounds of diverse etiologies, collected by three different methods, to develop a wound-specific, cell-based functional biomarker assay. Human dermal fibroblast proliferation served as readout to a) to differentiate between healing and non-healing wounds, b) follow the healing process of individual patients, and c) assess the effects of therapeutics for chronic wounds ex vivo. We observed a strong correlation between wound chronicity and inhibitory effects of individual exudates on fibroblast proliferation, with good diagnostic sensitivity (76-90%, depending on the sample collection method). Transition of a clinically non-healing to a healing phenotype restored fibroblast proliferation and extracellular matrix formation while reducing inflammatory cytokine production. Transcriptional analysis of fibroblasts exposed to ex vivo non-healing wound exudates revealed an induction of inflammatory cytokine- and chemokine pathways and the unfolded protein response, indicating that these changes may contribute to the pathology of non-healing wounds. Testing the wound therapeutics platelet derived growth factor and silver sulfadiazine yielded responses in line with clinical experience and indicate the usefulness of the assay to search for and profile new therapeutics.

3.
J Immunol Methods ; 530: 113696, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38797274

RESUMEN

Autoantibodies against type I interferon (IFN) are associated with a worse outcome in COVID-19. The measurement of cytokine-neutralizing autoantibodies has been limited, hindering understanding of their role in clinical practice. We showed that an easy and reliable assay can be reproduced and validated to measure the neutralizing potency of autoantibodies directed to type I or type II IFN. Identifying of anti-cytokine autoantibodies might reflect on early treatments for subsequent infections, such as with antivirals or virus-neutralizing monoclonal antibodies.


Asunto(s)
Anticuerpos Neutralizantes , Autoanticuerpos , COVID-19 , SARS-CoV-2 , Humanos , Autoanticuerpos/sangre , Autoanticuerpos/inmunología , COVID-19/inmunología , COVID-19/diagnóstico , COVID-19/sangre , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/sangre , SARS-CoV-2/inmunología , Citocinas/inmunología , Citocinas/sangre , Interferón Tipo I/inmunología , Masculino , Femenino , Persona de Mediana Edad , Reproducibilidad de los Resultados
4.
Autoimmunity ; 57(1): 2341629, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38616577

RESUMEN

Most investigations on the immune cell-activating potency of IgA used purified total IgA and/or specific isolated cell populations. As IgA2 has been reported to be more pro-inflammatory than IgA1, we aimed to employ a fast and convenient whole blood-based assay to individually probe the capacity of the two IgA subclasses to activate immune cells in close physiological conditions. To this end, whole blood from healthy donors (n = 10) was stimulated with immobilized IgA1, IgA2m1 or IgA2m2 (the two main allotypic variants of IgA2). Activation of major leukocyte subsets was measured using a 10-color flow cytometry panel providing access to the expression of 5 activation markers on 6 different immune cell subsets. While capturing some heterogeneity of responses among donors, IgA2m1 and IgA2m2 systematically showed a stronger activation profile compared to IgA1 in a variety of dimensions. For example, both IgA2 allotypes led to stronger modulations of CD54, CD11b, CD62L, CD66b or CD69, on both or either monocytes or neutrophils, indicating a more pronounced pro-inflammatory effect for this subclass than IgA1. By taking into account donor-specific soluble and cellular components this whole blood-based functional approach provides new perspectives to further investigate IgA effector functions in mechanistic studies and/or translational research.


Asunto(s)
Inmunoglobulina A , Monocitos , Neutrófilos , Leucocitos , Citometría de Flujo
5.
Front Immunol ; 15: 1374293, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38680489

RESUMEN

Introduction: Shigella is the etiologic agent of a bacillary dysentery known as shigellosis, which causes millions of infections and thousands of deaths worldwide each year due to Shigella's unique lifestyle within intestinal epithelial cells. Cell adhesion/invasion assays have been extensively used not only to identify targets mediating host-pathogen interaction, but also to evaluate the ability of Shigella-specific antibodies to reduce virulence. However, these assays are time-consuming and labor-intensive and fail to assess differences at the single-cell level. Objectives and methods: Here, we developed a simple, fast and high-content method named visual Adhesion/Invasion Inhibition Assay (vAIA) to measure the ability of anti-Shigellaantibodies to inhibit bacterial adhesion to and invasion of epithelial cells by using the confocal microscope Opera Phenix. Results: We showed that vAIA performed well with a pooled human serum from subjects challenged with S. sonnei and that a specific anti-IpaD monoclonal antibody effectively reduced bacterial virulence in a dose-dependent manner. Discussion: vAIA can therefore inform on the functionality of polyclonal and monoclonal responses thereby supporting the discovery of pathogenicity mechanisms and the development of candidate vaccines and immunotherapies. Lastly, this assay is very versatile and may be easily applied to other Shigella species or serotypes and to different pathogens.


Asunto(s)
Anticuerpos Antibacterianos , Adhesión Bacteriana , Disentería Bacilar , Humanos , Adhesión Bacteriana/inmunología , Disentería Bacilar/inmunología , Disentería Bacilar/microbiología , Disentería Bacilar/diagnóstico , Anticuerpos Antibacterianos/inmunología , Interacciones Huésped-Patógeno/inmunología , Shigella/inmunología , Shigella/patogenicidad , Células Epiteliales/microbiología , Células Epiteliales/inmunología , Shigella sonnei/inmunología , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/farmacología , Células HeLa
6.
Front Microbiol ; 15: 1361270, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38510998

RESUMEN

Introduction: Bacteria inhabit the in- and outside of the human body, such as skin, gut or the oral cavity where they play an innoxious, beneficial or even pathogenic role. It is well known that bacteria can secrete membrane vesicles (MVs) like eukaryotic cells with extracellular vesicles (EVs). Several studies indicate that bacterial membrane vesicles (bMVs) play a crucial role in microbiome-host interactions. However, the composition of such bMVs and their functionality under different culture conditions are still largely unknown. Methods: To gain a better insight into bMVs, we investigated the composition and functionality of E. coli (DSM 105380) bMVs from the culture media Lysogeny broth (LB) and RPMI 1640 throughout the different phases of growth (lag-, log- and stationary-phase). bMVs from three time points (8 h, 54 h, and 168 h) and two media (LB and RPMI 1640) were isolated by ultracentrifugation and analyzed using nanoparticle tracking analysis (NTA), cryogenic electron microscopy (Cryo-EM), conventional transmission electron microscopy (TEM) and mass spectrometry-based proteomics (LC-MS/MS). Furthermore, we examined pro-inflammatory cytokines IL-1ß and IL-8 in the human monocyte cell line THP-1 upon bMV treatment. Results: Particle numbers increased with inoculation periods. The bMV morphologies in Cryo-EM/TEM were similar at each time point and condition. Using proteomics, we identified 140 proteins, such as the common bMV markers OmpA and GroEL, present in bMVs isolated from both media and at all time points. Additionally, we were able to detect growth-condition-specific proteins. Treatment of THP-1 cells with bMVs of all six groups lead to significantly high IL-1ß and IL-8 expressions. Conclusion: Our study showed that the choice of medium and the duration of culturing significantly influence both E. coli bMV numbers and protein composition. Our TEM/Cryo-EM results demonstrated the presence of intact E. coli bMVs. Common E. coli proteins, including OmpA, GroEL, and ribosome proteins, can consistently be identified across all six tested growth conditions. Furthermore, our functional assays imply that bMVs isolated from the six groups retain their function and result in comparable cytokine induction.

7.
Hum Mol Genet ; 33(12): 1090-1104, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38538566

RESUMEN

RATIONALE: Pathogenic (P)/likely pathogenic (LP) SMAD3 variants cause Loeys-Dietz syndrome type 3 (LDS3), which is characterized by arterial aneurysms, dissections and tortuosity throughout the vascular system combined with osteoarthritis. OBJECTIVES: Investigate the impact of P/LP SMAD3 variants with functional tests on patient-derived fibroblasts and vascular smooth muscle cells (VSMCs), to optimize interpretation of SMAD3 variants. METHODS: A retrospective analysis on clinical data from individuals with a P/LP SMAD3 variant and functional analyses on SMAD3 patient-derived VSMCs and SMAD3 patient-derived fibroblasts, differentiated into myofibroblasts. RESULTS: Individuals with dominant negative (DN) SMAD3 variant in the MH2 domain exhibited more major events (66.7% vs. 44.0%, P = 0.054), occurring at a younger age compared to those with haploinsufficient (HI) variants. The age at first major event was 35.0 years [IQR 29.0-47.0] in individuals with DN variants in MH2, compared to 46.0 years [IQR 40.0-54.0] in those with HI variants (P = 0.065). Fibroblasts carrying DN SMAD3 variants displayed reduced differentiation potential, contrasting with increased differentiation potential in HI SMAD3 variant fibroblasts. HI SMAD3 variant VSMCs showed elevated SMA expression and altered expression of alternative MYH11 isoforms. DN SMAD3 variant myofibroblasts demonstrated reduced extracellular matrix formation compared to control cell lines. CONCLUSION: Distinguishing between P/LP HI and DN SMAD3 variants can be achieved by assessing differentiation potential, and SMA and MYH11 expression. The differences between DN and HI SMAD3 variant fibroblasts and VSMCs potentially contribute to the differences in disease manifestation. Notably, myofibroblast differentiation seems a suitable alternative in vitro test system compared to VSMCs.


Asunto(s)
Fibroblastos , Estudios de Asociación Genética , Síndrome de Loeys-Dietz , Músculo Liso Vascular , Proteína smad3 , Humanos , Proteína smad3/genética , Proteína smad3/metabolismo , Síndrome de Loeys-Dietz/genética , Síndrome de Loeys-Dietz/patología , Masculino , Femenino , Fibroblastos/metabolismo , Adulto , Persona de Mediana Edad , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patología , Diferenciación Celular/genética , Línea Celular , Miocitos del Músculo Liso/metabolismo , Estudios Retrospectivos , Fenotipo , Miofibroblastos/metabolismo , Miofibroblastos/patología , Mutación
8.
Arch Med Sci ; 20(1): 267-279, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38414469

RESUMEN

Introduction: The ITGB6 gene encoding a protein that can regulate the integrin αvß6 heterodimer protein expression in different status was shown to play an important role in multiple human cancers, such as brain cancer, colon cancer and oral cancer, and is related to clinical progression. This study aims to explore the function and the mechanism of the ITGB6 gene or protein in pancreatic cancer. Material and methods: We examined the expression of ITGB6 in pancreatic cancer using immunohistochemistry and analyzed the relationship between the expression of ITGB6 and the clinicopathologic features in pancreatic cancer patients. In addition, a bioinformatic method was used to analyze the ITGB6 mRNA level in pancreatic tumor tissues compared with normal pancreatic tissues and to analyze the correlation between high KIF23 expression and prognosis in pancreatic cancer patients. Moreover, colony formation assay, MTT assay, cell scratch, cell invasion and western blot assays in vitro and a xenograft mouse model in vivo were performed to analyze the effect of KIF23 on proliferation and invasion of pancreatic cancer cells. Results: Increased expression of ITGB6 was significantly correlated with poor clinical outcome in both our clinical data and TCGA data of pancreatic cancer. Furthermore, functional assays revealed that ITGB6 knockdown in vivo and in vitro might inhibit cancer cell proliferation and the ability of invasion or migration. Conclusions: Our data suggest that ITGB6 is associated with pancreatic cancer malignant progression. Hence, ITGB6 may serve as a potential target of pancreatic cancer for future research, and further study is needed.

9.
ACS Biomater Sci Eng ; 10(3): 1856-1868, 2024 03 11.
Artículo en Inglés | MEDLINE | ID: mdl-38385618

RESUMEN

Alzheimer's disease (AD) is a neurodegenerative disease and the most frequent cause of dementia. It is characterized by the accumulation in the brain of two pathological protein aggregates: amyloid-ß peptides (Aß) and abnormally phosphorylated tau. The progressive cognitive decline observed in patients strongly correlates with the synaptic loss. Many lines of evidence suggest that soluble forms of Aß accumulate into the brain where they cause synapse degeneration. Stopping their spreading and/or targeting the pathophysiological mechanisms leading to synaptic loss would logically be beneficial for the patients. However, we are still far from understanding these processes. Our objective was therefore to develop a versatile model to assay and study Aß-induced synaptotoxicity. We integrated a microfluidic device that physically isolates synapses from presynaptic and postsynaptic neurons with a microelectrode array. We seeded mouse primary cortical cells in the presynaptic and postsynaptic chambers. After functional synapses have formed in the synaptic chamber, we exposed them to concentrated conditioned media from cell lines overexpressing the wild-type or mutated amyloid precursor protein and thus secreting different levels of Aß. We recorded the neuronal activity before and after exposition to Aß and quantified Aß's effects on the connectivity between presynaptic and postsynaptic neurons. We observed that the application of Aß on the synapses for 48 h strongly decreased the interchamber connectivity without significantly affecting the neuronal activity in the presynaptic or postsynaptic chambers. Thus, through this model, we are able to functionally assay the impact of Aß peptides (or other molecules) on synaptic connectivity and to use the latter as a proxy to study Aß-induced synaptotoxicity. Moreover, since the presynaptic, postsynaptic, and synaptic chambers can be individually targeted, our assay provides a powerful tool to evaluate the involvement of candidate genes in synaptic vulnerability and/or test therapeutic strategies for AD.


Asunto(s)
Enfermedad de Alzheimer , Enfermedades Neurodegenerativas , Ratones , Animales , Humanos , Microelectrodos , Péptidos beta-Amiloides/genética , Péptidos beta-Amiloides/química , Péptidos beta-Amiloides/metabolismo , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Dispositivos Laboratorio en un Chip
10.
ACS Chem Neurosci ; 15(4): 854-867, 2024 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-38345920

RESUMEN

Novel synthetic opioids (NSOs), including both fentanyl and non-fentanyl analogs that act as µ-opioid receptor (MOR) agonists, are associated with serious intoxication and fatal overdose. Previous studies proposed that G-protein-biased MOR agonists are safer pain medications, while other evidence indicates that low intrinsic efficacy at MOR better explains the reduced opioid side effects. Here, we characterized the in vitro functional profiles of various NSOs at the MOR using adenylate cyclase inhibition and ß-arrestin2 recruitment assays, in conjunction with the application of the receptor depletion approach. By fitting the concentration-response data to the operational model of agonism, we deduced the intrinsic efficacy and affinity for each opioid in the Gi protein signaling and ß-arrestin2 recruitment pathways. Compared to the reference agonist [d-Ala2,N-MePhe4,Gly-ol5]enkephalin, we found that several fentanyl analogs were more efficacious at inhibiting cAMP production, whereas all fentanyl analogs were less efficacious at recruiting ß-arrestin2. In contrast, the non-fentanyl 2-benzylbenzimidazole (i.e., nitazene) analogs were highly efficacious and potent in both the cAMP and ß-arrestin2 assays. Our findings suggest that the high intrinsic efficacy of the NSOs in Gi protein signaling is a common property that may underlie their high risk of intoxication and overdose, highlighting the limitation of using in vitro functional bias to predict the adverse effects of opioids. In addition, the extremely high potency of many NSOs now infiltrating illicit drug markets further contributes to the danger posed to public health.


Asunto(s)
Analgésicos Opioides , Fentanilo , Fentanilo/farmacología , Analgésicos Opioides/farmacología , Receptores Opioides mu/agonistas , Transducción de Señal , Proteínas de Unión al GTP/metabolismo , Encefalinas/farmacología , Encefalina Ala(2)-MeFe(4)-Gli(5)/farmacología
11.
J Immunol Methods ; 526: 113618, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38237697

RESUMEN

The high burden of disease and the long-lasting sequelae following Streptococcus pyogenes (Strep A) infections make the development of an effective vaccine a global health priority. Streptolysin O (SLO), is a key toxin in the complex pathogenesis of Strep A infection. Antibodies are elicited against SLO after natural exposure and represent a key target for vaccine-induced immunity. Here we present the setup and characterization of a hemolysis assay to measure functionality of anti-SLO antibodies in human sera. Assay specificity, precision, linearity, reproducibility, and repeatability were determined. The assay was demonstrated to be highly sensitive, specific, reproducible, linear and performed well in assessing functionality of anti-SLO antibodies induced by exposed individuals. Moreover, different sources of critical reagents, in particular red- blood cells, have been compared and had minimal impact on assay performance. The assay presented here has throughput suitable for evaluating sera in vaccine clinical trials and sero-epidemiological studies to gain further insights into the functionality of infection- and vaccine-induced antibodies.


Asunto(s)
Infecciones Estreptocócicas , Vacunas , Humanos , Streptococcus pyogenes , Hemólisis , Reproducibilidad de los Resultados , Estreptolisinas/farmacología , Proteínas Bacterianas , Anticuerpos/farmacología , Infecciones Estreptocócicas/diagnóstico
12.
HGG Adv ; 5(2): 100270, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38219013

RESUMEN

Long QT syndrome (LQTS), caused by the dysfunction of cardiac ion channels, increases the risk of sudden death in otherwise healthy young people. For many variants in LQTS genes, there is insufficient evidence to make a definitive genetic diagnosis. We have established a robust functional patch-clamp assay to facilitate classification of missense variants in KCNH2, one of the key LQTS genes. A curated set of 30 benign and 30 pathogenic missense variants were used to establish the range of normal and abnormal function. The extent to which variants reduced protein function was quantified using Z scores, the number of standard deviations from the mean of the normalized current density of the set of benign variant controls. A Z score of -2 defined the threshold for abnormal loss of function, which corresponds to 55% wild-type function. More extreme Z scores were observed for variants with a greater loss-of-function effect. We propose that the Z score for each variant can be used to inform the application and weighting of abnormal and normal functional evidence criteria (PS3 and BS3) within the American College of Medical Genetics and Genomics variant classification framework. The validity of this approach was demonstrated using a series of 18 KCNH2 missense variants detected in a childhood onset LQTS cohort, where the level of function assessed using our assay correlated to the Schwartz score (a scoring system used to quantify the probability of a clinical diagnosis of LQTS) and the length of the corrected QT (QTc) interval.


Asunto(s)
Síndrome de QT Prolongado , Mutación Missense , Niño , Humanos , Muerte Súbita , Canal de Potasio ERG1/genética , Corazón , Síndrome de QT Prolongado/diagnóstico
13.
Anticancer Agents Med Chem ; 24(5): 358-371, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37957911

RESUMEN

BACKGROUND: Thiazine, a 6-membered distinctive heterocyclic motif with sulfur and nitrogen atoms, is one of the heterocyclic compounds that functions as a core scaffold in a number of medicinally significant molecules. Small thiazine-based compounds may operate simultaneously on numerous therapeutic targets and by employing a variety of methods to halt the development, proliferation, and vasculature of cancer cells. We have, herein, reported a series of substituted 1,4 benzothiazines as potential anticancer agents for the treatment of lung cancer. METHODS: In order to synthesize 2,3-disubstituted-1,4 benzothiazines in good yield, a facile green approach for the oxidative cycloaddition of 2-amino benzenethiol and 1,3-dicarbonyls employing a catalytic amount of ceric ammonium nitrate has been devised. All the molecules have been characterized by spectral analysis and tested for anticancer activity against the A-549 lung cancer cell line using various functional assays. Further in silico screening of compound 3c against six crucial inflammatory molecular targets, such as Il1-α (PDB ID: 5UC6), Il1- ß (PDB ID: 6Y8I), Il6 (PDB ID: 1P9M), vimentin (PDB ID: 3TRT), COX-2 (PDB ID: 5KIR), Il8 (PDB ID: 5D14), and TNF-α (PDB ID: 2AZ5), was done using AutoDock tool. RESULTS: Among the synthesized compounds, propyl 3-methyl-3,4-dihydro-2H-benzo[b][1,4]thiazine-2- carboxylate (3c) was found to be most active based on cell viability assays using A-549 lung cancer cell line and was found to effectively downregulate various pro-inflammatory genes, like Il1-α, Il1-ß, Il6, vimentin, COX-2, Il8, and TNF-α in vitro. The ability of the molecule to effectively suppress the proliferation and migration of lung cancer cells in vitro has been further demonstrated by the colony formation unit assay and wound healing assay. Molecular docking analysis showed the maximal binding affinity (- 7.54 kcal/mol) to be exhibited by compound 3c against IL8. CONCLUSION: A green unconventional route for the synthesis of 2,3-disubstituted-1,4 benzothiazines has been developed. All the molecules were screened for their activity against lung cancer and the data suggested that the presence of an additional unbranched alkyl group attached to the thiazine ring increased their activity. Also, in vitro and in silico modeling confirmed the anti-cancer efficiency of compound 3c, encouraging the exploration of such small molecules against cancer.


Asunto(s)
Antineoplásicos , Neoplasias Pulmonares , Tiazinas , Humanos , Simulación del Acoplamiento Molecular , Vimentina , Relación Estructura-Actividad , Línea Celular Tumoral , Ciclooxigenasa 2 , Interleucina-6 , Interleucina-8/farmacología , Factor de Necrosis Tumoral alfa , Antineoplásicos/química , Tiazinas/farmacología , Neoplasias Pulmonares/tratamiento farmacológico , Proliferación Celular , Ensayos de Selección de Medicamentos Antitumorales
14.
Ann Biomed Eng ; 52(2): 327-341, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37899379

RESUMEN

The integrity of the barrier between blood and the selective filtrate of solutes is important for homeostasis and its disruption contributes to many diseases. Microphysiological systems that incorporate synthetic or natural membranes with human cells can mimic biological filtration barriers, such as the glomerular filtration barrier in the kidney, and they can readily be used to study cellular filtration processes as well as drug effects and interactions. We present an affordable, open-source platform for the real-time monitoring of functional filtration status in engineered microphysiological systems. Using readily available components, our assay can linearly detect real-time concentrations of two target molecules, FITC-labeled inulin and Texas Red-labeled human-serum albumin, within clinically relevant ranges, and it can be easily modified for different target molecules of varying sizes and tags. We demonstrate the platform's ability to determine the concentration of our target molecules automatically and consistently. We show through an acellular context that the platform enables real-time tracking of size-dependent diffusion with minimal fluid volume loss and without manual extraction of media, making it suitable for continuous operational monitoring of filtration status in microphysiological system applications. The platform's affordability and integrability with microphysiological systems make it ideal for many precision medicine applications, including evaluation of drug nephrotoxicity and other forms of drug discovery.


Asunto(s)
Barrera de Filtración Glomerular , Riñón , Humanos , Riñón/fisiología , Barrera de Filtración Glomerular/fisiología
16.
Pharmaceuticals (Basel) ; 16(12)2023 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-38139828

RESUMEN

Cystic fibrosis (CF), the most common autosomal recessive fatal genetic disease in the Caucasian population, is caused by mutations in the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR), an anion channel that regulates salt and water transport across a variety of secretory epithelia. Deletion of phenylalanine at position 508, F508del, the most common CF-causing mutation, destabilises the CFTR protein, causing folding and trafficking defects that lead to a dramatic reduction in its functional expression. Small molecules called correctors have been developed to rescue processing-defective F508del CFTR. We have combined in silico and in vitro approaches to investigate the mechanism of action and potential as CFTR correctors of three hybrid derivatives (2a, 7a, and 7m) obtained by merging the amino-arylthiazole core with the benzodioxole carboxamide moiety characterising the corrector lumacaftor. Molecular modelling analyses suggested that the three hybrids interact with a putative region located at the MSD1/NBD1 interface. Biochemical analyses confirmed these results, showing that the three molecules affect the expression and stability of the F508del NBD1. Finally, the YFP assay was used to evaluate the influence of the three hybrid derivatives on F508del CFTR function, assessing that their effect is additive to that of the correctors VX661 and VX445. Our study shows that the development and testing of optimised compounds targeting different structural and functional defects of mutant CFTR is the best strategy to provide more effective correctors that could be used alone or in combination as a valuable therapeutic option to treat an even larger cohort of people affected by CF.

17.
Cell Rep Methods ; 3(11): 100628, 2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-37922907

RESUMEN

Sequencing of genes, such as BRCA1 and BRCA2, is recommended for individuals with a personal or family history of early onset and/or bilateral breast and/or ovarian cancer or a history of male breast cancer. Such sequencing efforts have resulted in the identification of more than 17,000 BRCA2 variants. The functional significance of most variants remains unknown; consequently, they are called variants of uncertain clinical significance (VUSs). We have previously developed mouse embryonic stem cell (mESC)-based assays for functional classification of BRCA2 variants. We now developed a next-generation sequencing (NGS)-based approach for functional evaluation of BRCA2 variants using pools of mESCs expressing 10-25 BRCA2 variants from a given exon. We use this approach for functional evaluation of 223 variants listed in ClinVar. Our functional classification of BRCA2 variants is concordant with the classification reported in ClinVar or those reported by other orthogonal assays.


Asunto(s)
Genes BRCA2 , Neoplasias Ováricas , Humanos , Femenino , Masculino , Animales , Ratones , Células Madre Embrionarias de Ratones , Neoplasias Ováricas/genética , Proteína BRCA2/genética
18.
Methods Enzymol ; 692: 177-215, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37925179

RESUMEN

RNase J is involved in RNA maturation as well as degradation of RNA to the level of mononucleotides. This enzyme plays a vital role in maintaining intracellular RNA levels and governs different steps of the cellular metabolism in bacteria. RNase J is the first ribonuclease that was shown to have both endonuclease and 5'-3' exonuclease activity. RNase J enzymes can be identified by their characteristic sequence features and domain architecture. The quaternary structure of RNase J plays a role in regulating enzyme activity. The structure of RNase J has been characterized from several homologs. These reveal extensive overall structural similarity alongside a distinct active site topology that coordinates a metal cofactor. The metal cofactor is essential for catalytic activity. The catalytic activity of RNase J is influenced by oligomerization, the choice and stoichiometry of metal cofactors, and the 5' phosphorylation state of the RNA substrate. Here we describe the sequence and structural features of RNase J alongside phylogenetic analysis and reported functional roles in diverse organisms. We also provide a detailed purification strategy to obtain an RNase J enzyme sample with or without a metal cofactor. Different methods to identify the nature of the bound metal cofactor, the binding affinity and stoichiometry are presented. Finally, we describe enzyme assays to characterize RNase J using radioactive and fluorescence-based strategies with diverse RNA substrates.


Asunto(s)
Endorribonucleasas , Ribonucleasas , Ribonucleasas/metabolismo , Filogenia , Endorribonucleasas/metabolismo , ARN/química , Ribonucleasa Pancreática , Metales
19.
Front Immunol ; 14: 1279612, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37954579

RESUMEN

Factor I (FI) is an essential regulator of the complement system. Together with co-factors, FI degrades C3b, which inhibits further complement activation. Genetic mutations in FI are associated with pathological conditions like age-related macular degeneration and atypical hemolytic uremic syndome. Here, we evaluated eight recombinant FI genetic variants found in patients. We assessed FI's co-factor activity in the presence of two co-factors; Factor H and soluble CR1. Different analytical assays were employed; SDS-PAGE to evaluate the degradation of C3b, ELISA to measure the generation of fluid phase iC3b and the degradation of surface-bound C3b using a novel Luminex bead-based assay. We demonstrate that mutations in the FIMAC and SP domains of FI led to significantly reduced protease activity, whereas the two analyzed mutations in the LDLRA2 domain did not result in any profound changes in FI's function. The different assays employed displayed a strong positive correlation, but differences in the activity of the genetic variants Ile55Phe and Gly261Asp could only be observed by combining different methods and co-factors for evaluating FI activity. In conclusion, our results provide a new perspective regarding available diagnostic tools for assessing the impact of mutations in FI.


Asunto(s)
Complemento C3b , Factor I de Complemento , Humanos , Factor I de Complemento/genética , Factor I de Complemento/metabolismo , Complemento C3b/metabolismo , Mutación , Ensayo de Inmunoadsorción Enzimática , Electroforesis en Gel de Poliacrilamida
20.
Front Pediatr ; 11: 1269560, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37800011

RESUMEN

Acute lymphoblastic leukemia (ALL) is the most common pediatric cancer, with survival rates exceeding 85%. However, 15% of patients will relapse; consequently, their survival rates decrease to below 50%. Therefore, several research and innovation studies are focusing on pediatric relapsed or refractory ALL (R/R ALL). Driven by this context and following the European strategic plan to implement precision medicine equitably, the Relapsed ALL Network (ReALLNet) was launched under the umbrella of SEHOP in 2021, aiming to connect bedside patient care with expert groups in R/R ALL in an interdisciplinary and multicentric network. To achieve this objective, a board consisting of experts in diagnosis, management, preclinical research, and clinical trials has been established. The requirements of treatment centers have been evaluated, and the available oncogenomic and functional study resources have been assessed and organized. A shipping platform has been developed to process samples requiring study derivation, and an integrated diagnostic committee has been established to report results. These biological data, as well as patient outcomes, are collected in a national registry. Additionally, samples from all patients are stored in a biobank. This comprehensive repository of data and samples is expected to foster an environment where preclinical researchers and data scientists can seek to meet the complex needs of this challenging population. This proof of concept aims to demonstrate that a network-based organization, such as that embodied by ReALLNet, provides the ideal niche for the equitable and efficient implementation of "what's next" in the management of children with R/R ALL.

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