RESUMEN
The selectin family consisting of E-, P- and L-selectin plays dominant roles in atherosclerosis, ischemia-reperfusion injury, inflammatory diseases, and metastatic spreading of some cancers. An early goal in selectin-targeted drug discovery campaigns was to identify ligands binding to all three selectins, so-called pan-selectin antagonists. The physiological epitope, tetrasaccharide sialyl Lewisx (sLex, 1) binds to all selectins, albeit with very different affinities. Whereas P- and L-selectin require additional interactions contributed by sulfate groups for high binding affinity, E-selectin can functionally bind sLex-modified glycolipids and glycoproteins. Rivipansel (3) marked the first pan-selectin antagonist, which simultaneously interacted with both the sLex and the sulfate binding site. The aim of this contribution was to improve the pan-selectin affinity of rivipansel (3) by leveraging a new class of sLex mimetics in combination with an optimized linker length to the sulfate bearing group. As a result, the pan-selectin antagonist 11b exhibits an approximatively 5-fold improved affinity for E-, as well as P-selectin.
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Selectinas , Humanos , Selectinas/metabolismo , Relación Estructura-Actividad , Oligosacáridos/química , Oligosacáridos/farmacología , Oligosacáridos/síntesis química , Estructura Molecular , Antígeno Sialil Lewis X , Relación Dosis-Respuesta a Droga , Selectina E/metabolismo , Selectina E/antagonistas & inhibidores , GlucolípidosRESUMEN
The leukocyte adhesion cascade governs the recruitment of circulating immune cells from the vasculature to distal sites. The initial adhesive interactions between cell surface ligands displaying sialyl-LewisX (sLeX) and endothelial E- and P-selectins serve to slow the cells down enough to interact more closely with the surface, polarize, and exit into the tissues. Therefore, precise microfluidic assays are critical in modeling how well immune cells can interact and "roll" on selectins to slow down enough to complete further steps of the cascade. Here, we present a systematic protocol for selectin mediated rolling on recombinant surfaces and endothelial cell monolayers on polyacrylamide gels of varying stiffness. We also describe step-by-step the protocol for setting up and performing the experiment and how to analyze and present the data collected. This protocol serves to simplify and detail the procedure needed to investigate the initial selectin-mediated interactions of immune cells with the vasculature. © 2024 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Preparing dishes for cell rolling experiments Basic Protocol 2: Fabrication of polyacrylamide gels for cell rolling experiments Alternate Protocol 1: Protein conjugation with N6 linker Alternate Protocol 2: HUVEC culturing for monolayers Basic Protocol 3: Conducting cell rolling experiments on polyacrylamide gels Basic Protocol 4: ImageJ analysis of cell rolling movies Basic Protocol 5: Quantification of Fc site density on a surface (e.g., for Fc chimeras).
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Microfluídica , Selectinas , Adhesión Celular , Antígeno Sialil Lewis X , LeucocitosRESUMEN
Insufficient data exist regarding the investigation of the impact of novel oral anticoagulants (NOACs) on coagulation activation biomarkers in the context of left atrial appendage closure (LAAC) and device-related thrombosis (DRT). The study was designed to investigate the changes and presence of coagulation activation biomarkers between different antithrombotic strategies following LAAC. A total of 120 nonvalvular atrial fibrillation patients intolerant of long-term anticoagulants, who underwent successful WATCHMAN closure implantation, were enrolled (rivaroxaban, n = 82; dabigatran, n = 38). Blood samples were obtained from left atrium (LA) and left atrial appendage (LAA) during the operation and fasting blood samples on the same day of LAAC and 45 days after discharge. The biochemical indicators, thrombin-antithrombin complex (TAT), soluble P-selectin (sP-selectin), von Willebrand factor (vWF), and CD40 ligand (CD40L), were measured by enzyme-linked immunosorbent assay. The primary endpoints of this study were the efficacy and safety characteristics of different antithrombotic strategies, including DRT incidence, stroke or transient ischemic attack, systemic embolism, and clinical major and nonmajor bleeding complications during the follow-up of 180 days. The results revealed that TAT, vWF, sP-selectin, and CD40L levels in vein were significantly reduced by 2.4% (p = 0.043), 5.0% (p < 0.001), 8.7% (p < 0.001), and 2.5% (p = 0.043) from their baseline levels after rivaroxaban treatment. Conversely, no significant changes were detected in the dabigatran group. Furthermore, the plasma levels of platelet activation biomarkers (CD40L and sP-selectin) in both LA and LAA groups were significantly lower after anticoagulation with rivaroxaban, as compared to dabigatran treatment (CD40L: 554.62 ± 155.54 vs. 445.02 ± 130.04 for LA p = 0.0013, 578.51 ± 156.28 vs. 480.13 ± 164.37 for LAA p = 0.0052; sP-selectin: 2849.07 ± 846.69 vs. 2225.54 ± 799.96 for LA p = 0.0105, 2915.52 ± 1402.40 vs. 2203.41 ± 1061.67 for LAA p = 0.0022). Notably, the present study suggests that rivaroxaban may be more effective in the prevention of DRT for patients undergoing LAAC.
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Apéndice Atrial , Fibrilación Atrial , Accidente Cerebrovascular , Trombosis , Humanos , Rivaroxabán/efectos adversos , Anticoagulantes/efectos adversos , Dabigatrán/efectos adversos , Cierre del Apéndice Auricular Izquierdo , Administración Oral , Factor de von Willebrand/farmacología , Factor de von Willebrand/uso terapéutico , Fibrinolíticos/uso terapéutico , Ligando de CD40/farmacología , Ligando de CD40/uso terapéutico , Resultado del Tratamiento , Accidente Cerebrovascular/prevención & control , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/tratamiento farmacológico , Fibrilación Atrial/complicaciones , Activación Plaquetaria , Biomarcadores , Selectinas/farmacología , Selectinas/uso terapéuticoRESUMEN
Among the long-standing efforts to elucidate the physical mechanisms of protein-ligand catch bonding, particular attention has been directed at the family of selectin proteins. Selectins exhibit slip, catch-slip, and slip-catch-slip bonding, with minor structural modifications causing major changes in selectins' response to force. How can a single structural mechanism allow interconversion between these various behaviors? We present a unifying theory of selectin-ligand catch bonding, using a structurally motivated free energy landscape to show how the topology of force-induced deformations of the molecular system produces the full range of observed behaviors. We find that the pathway of bond rupture deforms in non-trivial ways, such that unbinding dynamics depend sensitively on force. This implies a severe breakdown of Bell's theory-a paradigmatic theory used widely in catch bond modeling-raising questions about the suitability of Bell's theory in modeling other catch bonds. Our approach can be applied broadly to other protein-ligand systems.
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Proteínas , Selectinas , Ligandos , Selectinas/química , Unión ProteicaRESUMEN
BACKGROUND: Increasing evidence suggests an association between schizophrenia and atherosclerosis. We conducted a systematic review and meta-analysis of cell adhesion molecules, critically involved in early atherosclerosis, in schizophrenia. METHODS: We searched electronic databases from inception to 11 November 2023 for case-control studies assessing vascular cell, VCAM-1, intercellular, ICAM-1, platelet endothelial cell, PECAM-1, neural cell, NCAM, and Down syndrome cell, DSCAM, adhesion molecules, selectins (E-, L-, and P-selectin), integrins, and cadherins in patients with schizophrenia and healthy controls. Risk of bias and certainty of evidence were assessed using the JBI checklist and GRADE, respectively. RESULTS: In 19 eligible studies, there were non-significant between-group differences in the concentrations of cell adhesion molecules, barring higher P-selectin in patients with schizophrenia (standard mean difference, SMD = 2.05, 95 % CI 0.72 to 3.38, p = 0.003; I2 = 97.2 %, p<0.001; very low certainty of evidence). Limited or no information was available regarding PECAM-1, DSCAM, ESAM, integrins, and cadherins. In meta-regression and subgroup analysis, there were significant associations between the SMD of ICAM-1 and matrix used (plasma or serum) and pharmacological treatment of schizophrenia, and between the SMD of VCAM-1 and pharmacological treatment, but not with other study and patient characteristics. CONCLUSIONS: The results of our systematic review and meta-analysis do not support a significant role of immunoglobulin-like adhesion molecules, selectins, integrins, or cadherins in mediating the associations between schizophrenia, atherosclerosis, and cardiovascular disease. Further studies are warranted to investigate these associations in patients with different cardiovascular risk and the effects of antipsychotic treatments on cell adhesion molecules and surrogate markers of atherosclerosis (PROSPERO registration number: CRD42023463916).
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Aterosclerosis , Esquizofrenia , Humanos , Cadherinas , Moléculas de Adhesión Celular , Selectina E/análisis , Integrinas/análisis , Molécula 1 de Adhesión Intercelular , Selectina-P/análisis , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/análisis , Selectinas , Molécula 1 de Adhesión Celular Vascular/análisisRESUMEN
Sickle cell anemia (SCA) causes a long-standing vascular inflammation state, leading to endothelial dysfunction and chronic overexpression of several adhesion molecules, which contributes to acute and constant vaso-occlusive (VOC) episodes. It has been demonstrated that hydroxyurea (HU) can reduce VOC events, organ damage, blood transfusions, and even the adhesion properties to endothelial cells of SCA subjects. Due to VOC episodes, these patients are also more susceptible to recurrent bacterial translocation and dysbiosis. Given this, our study aimed to uncover the interplay between adhesion molecules, gut microbiome, and hydroxyurea in a population of Angolan SCA children. Serum and fecal samples were obtained before and after HU treatment in 35 children. After HU, four of these adhesion molecules were significantly reduced: sE-selectin (p = 0.002), ADAMTS13 (p = 0.023), sICAM-1 (p = 0.003), and sVCAM-1 (p = 0.018). A positive correlation was observed between the number of neutrophils and sICAM-1, platelets, and sP-selectin, and also between leukocytes, sICAM-1, and sVCAM-1. Most taxa showing a significant correlation mainly belonged to the Clostridiales order. Specifically, from the Clostridium genera, the groups g19, g21, and g34 were all negatively correlated with HbF levels; g19, g21, and g24 positively correlated with leukocytes; g19 positively with neutrophils and sVCAM-1; and g34 positively with E- and P-selectin. Serratia, an opportunistic pathogen, was positively correlated with sE-selectin and sICAM-1 levels. Additionally, a negative correlation was observed between sP-selectin and Bifidobacterium. Research studies in this area could improve our understanding and contribute to finding new prognostic biomarkers to guarantee precise SCA patient stratification and predict severe complications.
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Anemia de Células Falciformes , Microbioma Gastrointestinal , Compuestos Orgánicos Volátiles , Niño , Humanos , Hidroxiurea/uso terapéutico , Células Endoteliales , Moléculas de Adhesión Celular , Anemia de Células Falciformes/tratamiento farmacológico , SelectinasRESUMEN
ABSTRACT: Data from a small trial in patients with cancer suggest that isoquercetin (IQ) treatment lowered thrombosis biomarkers and prevented clinical thrombosis, but, to our knowledge, no studies of IQ have been conducted to target thromboinflammation in adults with sickle cell disease (SCD). We conducted a randomized, double-blind, placebo-controlled trial in adults with steady-state SCD (hemoglobin SS [HbSS], HbSß0thal, HbSß+thal, or HbSC). The primary outcome was the change in plasma soluble P-selectin (sP-selectin) after treatment compared with baseline, analyzed in the intention-to-treat population. Between November 2019 and July 2022, 46 patients (aged 40 ± 11 years, 56% female, 75% under hydroxyurea treatment) were randomized to receive IQ (n = 23) or placebo (n = 23). IQ was well tolerated and all the adverse events (AEs; n = 21) or serious AEs (n = 14) recorded were not attributable to the study drug. The mean posttreatment change for sP-selectin showed no significant difference between the treatment groups (IQ, 0.10 ± 6.53 vs placebo, 0.74 ± 4.54; P = .64). In patients treated with IQ, whole-blood coagulation (P = .03) and collagen-induced platelet aggregation (P = .03) were significantly reduced from the baseline. Inducible mononuclear cell tissue factor gene expression and plasma protein disulfide isomerase reductase activity were also significantly inhibited (P = .003 and P = .02, respectively). Short-term fixed-dose IQ in patients with SCD was safe with no off-target bleeding and was associated with changes from the baseline in the appropriate direction for several biomarkers of thromboinflammation. The trial was registered at www.clinicaltrials.gov as #NCT04514510.
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Anemia de Células Falciformes , Trombosis , Adulto , Femenino , Humanos , Masculino , Anemia de Células Falciformes/complicaciones , Anemia de Células Falciformes/tratamiento farmacológico , Biomarcadores , Inflamación/tratamiento farmacológico , Inflamación/etiología , Selectinas , Tromboinflamación , Trombosis/tratamiento farmacológico , Trombosis/etiología , Método Doble CiegoRESUMEN
Ulcerative colitis (UC) is a chronic inflammatory bowel disease that primarily affects the mucosal layer of the colon (large intestine). However, the relationship between Intercellular Adhesion Molecule-1 (ICAM1), SELL and UC is unclear. The UC datasets, GSE87466 and GSE36807, were downloaded from the gene expression omnibus database. The R package limma was utilized to identify differentially expressed genes (DEGs). Weighted gene co-expression network analysis was conducted. The construction and analysis of protein-protein interaction network, functional enrichment analysis, gene set enrichment analysis, and comparative toxicogenomics database analysis were performed. TargetScan was employed to screen miRNAs regulating central DEGs. Western blot (WB) was used to verify. A total of 2118 DEGs were identified in our study. Gene ontology analysis indicated their enrichment primarily in immune system processes, cellular responses to chemical stimuli, responses to organic substances, responses to external stimuli, and immune responses. Kyoto Encyclopedia of Genes and Genomes analysis revealed that the target cells were mainly enriched in chemokine signaling pathways and TNF signaling pathways. Gene set enrichment analysis enrichment analysis showed significant enrichment in chemokine signaling pathways and cell adhesion molecules. In the Metascape enrichment project, gene ontology terms included regulation of cell activation and positive regulation of immune response. Through the construction and analysis of a protein-protein interaction network, we identified 11 core genes (ICAM1, SELL, CD44, CD40, CCR7, CXCL8, CD19, CCL4, CD274, IL7R, IL1B). We found that the core genes (ICAM1, SELL) were highly expressed in UC samples and lowly expressed in normal samples, suggesting their potential regulatory roles in UC. These core genes were associated with lymphoproliferative disorders, inflammation and necrosis. WB results confirmed the high expression of ICAM1 and SELL in UC. ICAM1 and SELL are highly expressed in UC, and the higher the ICAM1 and SELL genes, the worse the prognosis.
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Colitis Ulcerosa , Molécula 1 de Adhesión Intercelular , Selectinas , Humanos , Quimiocinas/genética , Colitis Ulcerosa/genética , Biología Computacional/métodos , Perfilación de la Expresión Génica , Redes Reguladoras de Genes , Molécula 1 de Adhesión Intercelular/genética , Selectinas/genéticaRESUMEN
PURPOSE: Assessment of individual VTE risk in cancer patients prior to chemotherapy is critical for determining necessity of interventions. Risk assessment models (RAM) are available but have not been validated for haematological malignancy. We aimed to assess the validity of the Vienna Cancer and Thrombosis Study (V-CATS) score in prediction of VTE in a variety of haematological malignancies. METHODS: This is a prospective cohort study conducted on 81 newly diagnosed cancer patients undergoing chemotherapy. Demographic, clinical and cancer related data were collected, patients were followed up for 6 months, and VTE events were recorded. Khorana score (KS) was calculated. Plasma D-dimer and sP-selectin were measured, and then, V-CATS score was calculated. Receiver operator curve (ROC) was used to assess the sensitivity and specificity of RAMs. A modified V-CATS was generated and subsequently assessed by using new cut-off levels of d-dimer and sP-selectin based on ROC curve of the patients' results and compared the probability of VTE occurrence using all three RAMs. RESULTS: Among the 81 patients included in this study, a total of 2.7% were diagnosed with advanced metastatic cancer. The most frequent cancer was non-Hodgkin lymphoma (39.5%), and 8 patients (9.8%) developed VTE events. The calculated probability of VTE occurrence using KS, V-CATS and modified V-CATS scores at cut-off levels ≥ 3 was 87.5%, 87.5% and 100%, respectively. The AUC in ROC curve of modified Vienna CATS score showed significant difference when compared to that of V-CATS and KS (P = 0.047 and 0.029, respectively). CONCLUSION: The findings of our study highlight the value of three VTE risk assessment models in haematological malignancies. The modified V-CATS score demonstrated higher specificity compared to both V-CATS and KS, while all three scores exhibited similar sensitivity. We encourage the implementation of RAMs in haematological cancers for an appropriate use of thromboprophylaxis.
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Neoplasias Hematológicas , Neoplasias , Tromboembolia Venosa , Humanos , Tromboembolia Venosa/epidemiología , Tromboembolia Venosa/etiología , Factores de Riesgo , Anticoagulantes , Estudios Prospectivos , Neoplasias/patología , Medición de Riesgo , Neoplasias Hematológicas/complicaciones , Neoplasias Hematológicas/tratamiento farmacológico , Selectinas , Estudios RetrospectivosRESUMEN
INTRODUCTION: This study aimed to investigate circulating biomarkers associated with the risk of developing diabetic peripheral neuropathy (DPN) and nephropathy in type 1 diabetes (T1D). MATERIALS AND METHODS: Patients with childhood-onset T1D (n = 49, age 38.3 ± 3.8 yrs.) followed prospectively were evaluated after 30 years of diabetes duration. DPN was defined as an abnormality in nerve conduction tests. Matrix metalloproteinase-9 (MMP-9) and its tissue inhibitor TIMP-1, neutrophil gelatinase-associated lipocalin-2 (NGAL), soluble P-selectin (sP-selectin), estimated GFR (eGFR), micro/macroalbuminuria and routine biochemistry were assessed. For comparison, control subjects were included (n = 30, age 37.9 ± 5.5 yrs.). RESULTS: In all, twenty-five patients (51 %) were diagnosed with DPN, and nine patients (18 %) had nephropathy (five microalbuminuria and four macroalbuminuria). Patients with DPN had higher levels of TIMP-1 (p = 0.036) and sP-selectin (p = 0.005) than controls. Patients with DPN also displayed higher levels of TIMP-1 compared to patients without DPN (p = 0.035). Patients with macroalbuminuria had kidney disease stage 3 with lower eGFR, higher levels of TIMP-1 (p = 0.038), and NGAL (p = 0.002). In all patients, we found only weak negative correlations between eGFR and TIMP-1 (rho = -0.304, p = 0.040) and NGAL (rho = -0.277, p = 0.062, ns), respectively. MMP-9 was higher in patients with microalbuminuria (p = 0.021) compared with normoalbuminuric patients. CONCLUSIONS: Our findings indicate that TIMP-1 and MMP-9, as well as sP-selectin and NGAL, are involved in microvascular complications in T1D. Monitoring and targeting these biomarkers may be a potential strategy for treating diabetic nephropathy and neuropathy.
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Diabetes Mellitus Tipo 1 , Nefropatías Diabéticas , Humanos , Niño , Adulto , Lipocalina 2 , Diabetes Mellitus Tipo 1/complicaciones , Inhibidor Tisular de Metaloproteinasa-1 , Metaloproteinasa 9 de la Matriz , Estudios de Seguimiento , Proteínas de Fase Aguda , Lipocalinas , Proteínas Proto-Oncogénicas , Estudios Prospectivos , Biomarcadores , Nefropatías Diabéticas/diagnóstico , SelectinasRESUMEN
Purpose: To measure the levels of inflammatory factors in tear fluid of pre-term infants with and without retinopathy of prematurity (ROP). Methods: The cross-sectional pilot study included 29 pre-term infants undergoing routine ROP screening. Pre-term infants were grouped as those without ROP (no ROP; n = 14) and with ROP (ROP; n = 15). Sterile Schirmer's strips were used to collect the tear fluid from pre-term infants. Inflammatory factors such as interleukin (IL)-6, IL-8, MCP1 (Monocyte Chemoattractant Protein 1; CCL2), RANTES (Regulated on Activation, Normal T Cell Expressed and Secreted; CCL5), and soluble L-selectin (sL-selectin) were measured by cytometric bead array using a flow cytometer. Results: Birth weight (BW) and gestation age (GA) were significantly (P < 0.05) lower in pre-term infants with ROP compared with those without ROP. Higher levels of RANTES (P < 0.05) and IL-8 (P = 0.09) were observed in the tear fluid of pre-term infants with ROP compared with those without ROP. Lower levels of tear fluid IL-6 (P = 0.14) and sL-selectin (P = 0.18) were measured in pre-term infants with ROP compared with those without ROP. IL-8 and RANTES were significantly (P < 0.05) higher in the tear fluid of pre-term infants with stage 3 ROP compared with those without ROP. Tear fluid RANTES level was observed to be inversely associated with GA and BW of pre-term infants with ROP and not in those without ROP. Furthermore, the area under the curve and odds ratio analysis demonstrated the relevance of RANTES/BW (AUC = 0.798; OR-7.2) and RANTES/MCP1 (AUC = 0.824; OR-6.8) ratios in ROP. Conclusions: Distinct changes were observed in the levels of tear inflammatory factors in ROP infants. The status of RANTES in ROP suggests its possible role in pathobiology and warrants further mechanistic studies to harness it in ROP screening and management.
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Retinopatía de la Prematuridad , Recién Nacido , Lactante , Humanos , Retinopatía de la Prematuridad/diagnóstico , Estudios Transversales , Interleucina-8 , Proyectos Piloto , Edad Gestacional , Factores de Riesgo , Recien Nacido Prematuro , Peso al Nacer , Selectinas , Estudios RetrospectivosRESUMEN
BACKGROUND: Porto-sinusoidal vascular disorder (PSVD) is characterised by lesions involving portal veins and sinusoids in absence of cirrhosis with an unclear pathophysiology. However, its association with immunodeficiency, bowel disorders and abdominal bacterial infections supports the role of altered intestinal permeability and gut-derived endotoxins. The study aimed at assessing the association between serological markers of increased intestinal permeability, pro-aggregating/procoagulant state and liver injury in PSVD and portal hypertension. METHODS: Thirty-three patients with biopsy-proven PSVD and portal hypertension and 33 healthy subjects were submitted to a venous blood sampling for the measurement of zonulin and lipopolysaccharides (LPS) as markers of intestinal permeability, of s-Glycoprotein VI, sP-selectin, ADAMTS13 and von Willebrand factor (vWF), as markers of platelet aggregation and microvascular inflammation, factor VIII and F1 + 2 as markers of hypercoagulability. In 17 PSVD patients, histomorphological and immunohistochemical study on liver biopsies was performed. RESULTS: Compared with controls, PSVD patients had higher levels of LPS, zonulin, vWF, factor VIII and sP-selectin, F1 + 2. ADAMTS13 was reduced. Serum LPS correlated with zonulin, sP-selectin, FVIII and vWF. At histological analysis, PSVD specimens had increased LPS localisation, toll-like receptor-4(TLR4)-positive macrophages and platelet number compared with samples from healthy liver donors. TLR4+ macrophage number correlated with portal inflammation and fibrosis. Sinusoid dilation and capillarisation were observed. PSVD biopsies showed signs of biliary damage and reduced ductular reaction without alteration in Sox9+ cell population. CONCLUSIONS: PSVD patients display an altered intestinal permeability and endotoxemia correlated to a pro-aggregating/procoagulant state; histologically, PSVD was associated with increased TLR4+ cell involvement and platelet clumps within sinusoids. Our study suggests that LPS-TLR4 pathway could contribute to the pathophysiological basis of PSVD with portal hypertension.
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Endotoxinas , Hipertensión Portal , Humanos , Factor VIII , Factor de von Willebrand/metabolismo , Receptor Toll-Like 4 , Lipopolisacáridos , Hipertensión Portal/complicaciones , Cirrosis Hepática/complicaciones , Inflamación/complicaciones , SelectinasRESUMEN
Selectins and their ability to interact with specific ligands are a cornerstone in cell communication. Over the last three decades, a considerable wealth of experimental and molecular modeling insights into their structure and modus operandi were gathered. Nonetheless, explaining the role of individual selectin residues on a quantitative level remained elusive, despite its importance in understanding the structure-function relationship in these molecules and designing their inhibitors. This work explores essential interactions of selectin-ligand binding, employing a multiscale approach that combines molecular dynamics, quantum-chemical calculations, and residue interaction network models. Such an approach successfully reproduces most of the experimental findings. It proves to be helpful, with the potential for becoming an established tool for quantitative predictions of residue contribution to the binding of biomolecular complexes. The results empower us to quantify the importance of particular residues and functional groups in the protein-ligand interface and to pinpoint differences in molecular recognition by the three selectins. We show that mutations in the E-, L-, and P-selectins, e.g., different residues in positions 46, 85, 97, and 107, present a crucial difference in how the ligand is engaged. We assess the role of sulfation of tyrosine residues in PSGL-1 and suggest that TyrSO3- in position 51 interacting with Arg85 in P-selectin is a significant factor in the increased affinity of P-selectin to PSGL-1 compared to E- and L-selectins. We propose an original pharmacophore targeting five essential PSGL-binding sites based on the analysis of the selectin···PSGL-1 interactions.
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Selectina-P , Selectinas , Selectina-P/metabolismo , Antígeno Sialil Lewis X , Ligandos , Adhesión CelularRESUMEN
PURPOSE: We evaluated the safety, pharmacokinetics (PK), pharmacodynamics (PD), and immunogenicity of intravenous (IV) inclacumab, a fully human IgG4 anti-P-selectin monoclonal antibody in development for the treatment of sickle cell disease, at doses up to and exceeding those previously tested in healthy individuals. METHODS: In this phase 1, open-label, single-ascending-dose study, 15 healthy participants were enrolled into cohorts receiving 20 mg/kg (n = 6) or 40 mg/kg (n = 9) IV inclacumab and observed for up to 29 weeks post-dose. Safety, PK parameters, thrombin receptor-activating peptide (TRAP)-activated platelet-leukocyte aggregate (PLA) formation, P-selectin inhibition, plasma soluble P-selectin, and anti-drug antibodies were characterized. RESULTS: Two inclacumab-related treatment-emergent adverse events were reported in 1 participant; no dose-limiting toxicities were observed. Plasma PK parameters were generally dose-proportional, with a terminal half-life of 13 to 17 days. Mean TRAP-activated PLA formation decreased within 3 h from the start of infusion, and inhibition was sustained for ~ 23 weeks. Mean P-selectin inhibition > 90% was observed up to 12 weeks post-dose. The mean ratio of free to total soluble P-selectin decreased rapidly from pre-dose to end of infusion, then increased gradually to 78% of the baseline ratio by week 29. Treatment-emergent anti-drug antibodies were observed in 2 of 15 participants (13%), without apparent impact on safety, PK, or PD. CONCLUSIONS: Inclacumab was well tolerated, with PK as expected for a monoclonal antibody against a membrane-bound target and a long duration of PD effects after both single IV doses, supporting a prolonged dosing interval. TRIAL REGISTRATION: ACTRN12620001156976; registered November 4, 2020.
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Anemia de Células Falciformes , Anticuerpos Monoclonales , Humanos , Voluntarios Sanos , Anticuerpos Monoclonales/efectos adversos , Anemia de Células Falciformes/tratamiento farmacológico , Anemia de Células Falciformes/inducido químicamente , Selectinas , Poliésteres , Método Doble Ciego , Relación Dosis-Respuesta a DrogaRESUMEN
Sickle cell disease (SCD) is a hereditary hemoglobinopathy characterized by painful vaso-occlusive crises (VOC) and chronic hemolysis. The mononuclear phagocyte system is pivotal to SCD pathophysiology, but the mechanisms governing monocyte/macrophage differentiation remain unknown. This study examined the influence of hemolysis on circulating monocyte trajectories in SCD. We discovered that hemolysis stimulated CSF-1 production, partly by endothelial cells via Nrf2, promoting classical monocyte (CMo) differentiation into blood patrolling monocytes (PMo) in SCD mice. However, hemolysis also upregulated CCL-2 through IFN-I, inducing CMo transmigration and differentiation into tissue monocyte-derived macrophages. Blocking CMo transmigration by anti-P selectin antibody in SCD mice increased circulating PMo, corroborating that CMo-to-tissue macrophage differentiation occurs at the expense of CMo-to-blood PMo differentiation. We observed a positive correlation between plasma CSF-1/CCL-2 ratios and blood PMo levels in patients with SCD, underscoring the clinical significance of these two opposing factors in monocyte differentiation. Combined treatment with CSF-1 and anti-P selectin antibody more effectively increased PMo numbers and reduced stasis compared with single-agent therapies in SCD mice. Altogether, these data indicate that monocyte fates are regulated by the balance between two heme pathways, Nrf2/CSF-1 and IFN-I/CCL-2, and suggest that the CSF-1/CCL-2 ratio may present a diagnostic and therapeutic target in SCD.
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Anemia de Células Falciformes , Enfermedades Vasculares , Ratones , Animales , Hemólisis , Monocitos/metabolismo , Factor Estimulante de Colonias de Macrófagos/metabolismo , Factor Estimulante de Colonias de Macrófagos/uso terapéutico , Células Endoteliales/metabolismo , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Anemia de Células Falciformes/genética , Anemia de Células Falciformes/tratamiento farmacológico , Enfermedades Vasculares/metabolismo , Diferenciación Celular , Selectinas/metabolismo , Selectinas/uso terapéuticoRESUMEN
OBJECTIVES: We employed Mendelian randomization to determine whether genetically predicted circulating levels of endothelial-derived adhesion molecules (soluble intercellular adhesion molecule-1 [sICAM-1]), soluble vascular-leukocyte adhesion molecule-1 [sVCAM-1], and soluble-endothelial-leukocyte adhesion molecule [sE-selectin]) were associated with functional outcome after ischemic stroke. METHODS: Independent genetic variants robustly associated with soluble adhesion molecules, located at or close to the coding gene (cis), were used as genetic instruments. The functional outcome was evaluated using the 3-month modified Rankin Scale (mRS) score after ischemic stroke. A poor functional outcome was defined as mRS ≥ 3 at 3 months. We extracted summary data for functional outcome after ischemic stroke from the Genetics of Ischaemic Stroke Functional Outcome network (n = 6,021). RESULTS: Genetically elevated sICAM-1 (OR 1.28, 95% CI 1.05-1.56) and sE-selectin (OR 2.69, 95% CI 1.23-5.86) levels were related with poor post-stroke outcome. However, we found no evidence that genetically elevated sVCAM-1 were associated with post-stroke outcome (OR 1.36, 95% CI 0.39-4.66). CONCLUSIONS: We found that genetically elevated higher sICAM-1 and sE-selectin levels are associated with poor post-stroke outcome. Further studies are warranted to evaluate the potential of ICAM-1 and E-selectin to be drug targets for post-stroke recovery.
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Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/genética , Isquemia Encefálica/terapia , Molécula 1 de Adhesión Celular Vascular/genética , Accidente Cerebrovascular Isquémico/diagnóstico , Accidente Cerebrovascular Isquémico/genética , Accidente Cerebrovascular Isquémico/terapia , Análisis de la Aleatorización Mendeliana , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/genética , Accidente Cerebrovascular/terapia , Moléculas de Adhesión Celular/genética , Molécula 1 de Adhesión Intercelular/genética , SelectinasRESUMEN
The brain functions through neuronal circuits and networks that are synaptically connected. This type of connection can exist due to physical forces that interact to stabilize local contacts in the brain. Adhesion is a fundamental physical phenomenon that allows different layers, phases, and tissues to connect. Similarly, synaptic connections are stabilized by specialized adhesion proteins. This review discusses the basic physical and chemical properties of adhesion. Cell adhesion molecules (CAMs) such as cadherins, integrins, selectins, and immunoglobulin family of cell adhesion molecules (IgSF) will be discussed, and their role in physiological and pathological brain function. Finally, the role of CAMs at the synapse will be described. In addition, methods for studying adhesion in the brain will be presented.
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Moléculas de Adhesión Celular , Selectinas , Adhesión Celular/fisiología , Moléculas de Adhesión Celular/metabolismo , Selectinas/metabolismo , Integrinas/metabolismo , Encéfalo/metabolismoRESUMEN
Objective: Chronic hyperglycemia induces pathogenic changes in the vascular endothelium and leads to the development of microvascular complications in patients with type 2 diabetes mellitus. Early identification of markers of diabetes complications may help to minimize the risk of the development and progression of microvascular complications. Methods: This follow-up study was conducted in type 2 diabetic cohort aged between 30-70 years. Out of 160 eligible participants, 70 of them completed follow-up. Levels of cell adhesion molecules and selectins (VCAM-1, ICAM-1, E-selectin, L-selectin and P-selectin) at baseline and follow-up were measured using Randox Evidence biochip analyzer (UK). Development of microvascular complications (diabetic neuropathy, retinopathy and nephropathy) was evaluated. Results: During the follow-up (2 years, median), 31 (44.3%) developed diabetic neuropathy, 10 (14.3%) developed diabetic retinopathy and, 27 (38.6%) developed diabetic nephropathy. A significant difference in levels of cell adhesion molecules and selectins were found in type 2 diabetic patients with and without microvascular complications. Multiple logistic regression analysis reveals that baseline level of VCAM-1 is significantly associated with microvascular complications; diabetic neuropathy(p=0.028), retinopathy (p=0.007) and nephropathy(p=<0.001). Additionally, levels of P-selectin (p=0.05) and L-selectin (p=0.008) is associated with diabetic nephropathy while retinopathy associated with L-selectin (p=0.005) only. Conclusion: Cell adhesion molecules and selectins are indicators of microvascular complication among patients with type 2 diabetes (T2D). Association of these markers with the development of microvascular complications may provide additive information for developing strategies for diabetes management and prediction of microvascular complications.
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Diabetes Mellitus Tipo 2 , Nefropatías Diabéticas , Neuropatías Diabéticas , Retinopatía Diabética , Humanos , Adulto , Persona de Mediana Edad , Anciano , Molécula 1 de Adhesión Celular Vascular , Selectina L , Estudios de Seguimiento , Selectina-P , Molécula 1 de Adhesión Intercelular , Diabetes Mellitus Tipo 2/complicaciones , Nefropatías Diabéticas/etiología , Moléculas de Adhesión Celular , Selectinas , Retinopatía Diabética/epidemiología , Retinopatía Diabética/etiologíaRESUMEN
ß-glucosylceramide (ß-GlcCer) accumulates in Gaucher disease, but how ß-GlcCer, a Mincle ligand, causes characteristic neuroinflammation and neuronopathy is poorly understood. In this issue of Immunity, Shimizu et al. reveal that Mincle-dependent activation of microglia led to phagocytosis of neurons and neurologic symptoms.
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Lectinas , Microglía , Neuronas , Fagocitosis , SelectinasRESUMEN
BACKGROUND: Patients with COVID-19 are at increased risk of thrombosis, which is associated with altered platelet function and coagulopathy, contributing to excess mortality. OBJECTIVES: To characterize the mechanism of altered platelet function in COVID-19 patients. METHODS: The platelet proteome, platelet functional responses, and platelet-neutrophil aggregates were compared between patients hospitalized with COVID-19 and healthy control subjects using tandem mass tag proteomic analysis, Western blotting, and flow cytometry. RESULTS: COVID-19 patients showed a different profile of platelet protein expression (858 altered of the 5773 quantified). Levels of COVID-19 plasma markers were enhanced in the platelets of COVID-19 patients. Gene ontology pathway analysis demonstrated that the levels of granule secretory proteins were raised, whereas those of platelet activation proteins, such as the thrombopoietin receptor and protein kinase Cα, were lowered. Basally, platelets of COVID-19 patients showed enhanced phosphatidylserine exposure, with unaltered integrin αIIbß3 activation and P-selectin expression. Agonist-stimulated integrin αIIbß3 activation and phosphatidylserine exposure, but not P-selectin expression, were decreased in COVID-19 patients. COVID-19 patients had high levels of platelet-neutrophil aggregates, even under basal conditions, compared to controls. This association was disrupted by blocking P-selectin, demonstrating that platelet P-selectin is critical for the interaction. CONCLUSIONS: Overall, our data suggest the presence of 2 platelet populations in patients with COVID-19: one of circulating platelets with an altered proteome and reduced functional responses and another of P-selectin-expressing neutrophil-associated platelets. Platelet-driven thromboinflammation may therefore be one of the key factors enhancing the risk of thrombosis in COVID-19 patients.