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1.
Front Immunol ; 15: 1430057, 2024.
Article in English | MEDLINE | ID: mdl-39100678

ABSTRACT

The protozoan parasite Entamoeba histolytica is the causative agent of amebiasis, with clinical outcomes ranging from asymptomatic infections to severe invasive diseases. The innate immune system, particularly macrophages, is of paramount importance in resisting the invasion of host tissues and organs by the trophozoites of E. histolytica. Parasite-derived pathogenic factors, such as lectins, play a pivotal role in the promotion of macrophage polarization phenotypes that have undergone alteration. Nevertheless, the precise mechanisms by which E. histolytica modulates immune polarization remain largely unknown. The current study focused on the immunomodulatory effects of the Igl-C fragment of E. histolytica Gal/GalNAc lectin on macrophage polarization. These results demonstrated that Igl-C could induce the secretion of IL-1ß, IL-6, and other cytokines, activating a mixed M1/M2 polarization state. M1 polarization of macrophages occurs in the early stages and gradually transitions to M2 polarization in the later stages, which may contribute to the persistence of the infection. Igl-C induces the macrophage M1 phenotype and causes the release of immune effector molecules, including iNOS and cytokines, by activating the NF-κB p65 and JAK-STAT1 transcription factor signaling pathways. Furthermore, Igl-C supports the macrophage M2 phenotype via JAK-STAT3 and IL-4-STAT6 pathways, which activate arginase expression in later stages, contributing to the tissue regeneration and persistence of the parasite. The involvement of distinct signaling pathways in mediating this response highlights the complex interplay between the parasite and the host immune system. These findings enhance our understanding of the Igl-C-mediated pathogenic mechanisms during E. histolytica infection.


Subject(s)
Entamoeba histolytica , Entamoebiasis , Lectins , Macrophages , Entamoeba histolytica/immunology , Macrophages/immunology , Macrophages/metabolism , Macrophages/parasitology , Entamoebiasis/immunology , Entamoebiasis/parasitology , Animals , Mice , Lectins/metabolism , Lectins/immunology , Cytokines/metabolism , Macrophage Activation , Humans , Signal Transduction , Protozoan Proteins/immunology , Protozoan Proteins/metabolism
2.
ACS Appl Bio Mater ; 7(8): 5689-5701, 2024 Aug 19.
Article in English | MEDLINE | ID: mdl-39116418

ABSTRACT

Weak binding of carbohydrates with protein receptors possesses serious drawbacks in the advancement of therapeutics; however, the development of strategies for multipoint interactions between carbohydrates and protein can overcome these challenges. One such method is developed in this work where glycopolymer-grafted silica nanoparticles with a large number of carbohydrate units are prepared for the interactions with multiple binding sites of the protein. First, a glycomonomer, ß-d-galactose-hydroxyethyl methacrylate (ß-GEMA), was synthesized in a two-step process by coupling ß-d-galactose pentaacetate and hydroxyethyl methacrylate (HEMA), followed by deacetylation for the preparation of poly(ß-GEMA) glycopolymers (GPs). Further, the poly(ß-GEMA) chains were grafted onto the silica nanoparticle (SiNP) surface by utilizing the "grafting-from" strategy of surface-initiated reversible addition-fragmentation chain transfer (RAFT) polymerization to prepare p(ß-GEMA)-grafted SiNPs (GNPs). Five different chain lengths ranging from 10 to 40 kDa of the GPs and the GNPs were prepared, and various characterization techniques confirmed the formation of GPs and grafting of the GPs on the SiNP surface. The particle size of GNPs and the number of GPs grafted on the SiNP surface showed a strong dependence on the chain length of the GPs. Further, the GNPs were subjected to a binding study with ß-galactose-specific protein peanut agglutinin (PNA). A much stronger binding in the case of GNPs was observed with an association constant ∼320 times and ∼53 times than that of the monomeric methyl-ß-d-galactopyranoside and the GPs, respectively. Additionally, the binding of the PNA with GNPs and GPs was also studied with varying chain lengths to understand the effects of the chain length on the binding affinity. A clear increase in binding constants was observed in the case of GNPs with increasing chain length of grafted GPs, attributed to the enhanced enthalpic and entropic contributions. This work holds its uniqueness in these improved interactions between carbohydrates and proteins, which can be used for carbohydrate-based targeted therapeutics.


Subject(s)
Galactose , Nanoparticles , Silicon Dioxide , Nanoparticles/chemistry , Galactose/chemistry , Silicon Dioxide/chemistry , Particle Size , Materials Testing , Biocompatible Materials/chemistry , Biocompatible Materials/chemical synthesis , Lectins/chemistry , Lectins/metabolism , Polymers/chemistry , Polymers/chemical synthesis , Protein Binding , Surface Properties
3.
Front Immunol ; 15: 1436039, 2024.
Article in English | MEDLINE | ID: mdl-39148735

ABSTRACT

Klebsiella pneumoniae is an opportunistic bacterium that frequently colonizes the nasopharynx and gastrointestinal tract and can also cause severe infections when invading other tissues, particularly in immunocompromised individuals. Moreover, K. pneumoniae variants exhibiting a hypermucoviscous (HMV) phenotype are usually associated with hypervirulent strains that can produce invasive infections even in immunocompetent individuals. Major carbohydrate structures displayed on the K. pneumoniae surface are the polysaccharide capsule and the lipopolysaccharide, which presents an O-polysaccharide chain in its outermost part. Various capsular and O-chain structures have been described. Of note, production of a thick capsule is frequently observed in HMV variants. Here we examined the surface sugar epitopes of a collection of HMV and non-HMV K. pneumoniae clinical isolates and their recognition by several Siglecs and galectins, two lectin families of the innate immune system, using bacteria microarrays as main tool. No significant differences among isolates in sialic acid content or recognition by Siglecs were observed. In contrast, analysis of the binding of model lectins with diverse carbohydrate-binding specificities revealed striking differences in the recognition by galactose- and mannose-specific lectins, which correlated with the binding or lack of binding of galectins and pointed to the O-chain as the plausible ligand. Fluorescence microscopy and microarray analyses of galectin-9 binding to entire cells and outer membranes of two representative HMV isolates supported the bacteria microarray results. In addition, Western blot analysis of the binding of galectin-9 to outer membranes unveiled protein bands recognized by this galectin, and fingerprint analysis of these bands identified several proteins containing potential O-glycosylation sites, thus broadening the spectrum of possible galectin ligands on the K. pneumoniae surface. Moreover, Siglecs and galectins apparently target different structures on K. pneumoniae surfaces, thereby behaving as non-redundant complementary tools of the innate immune system.


Subject(s)
Galectins , Immunity, Innate , Klebsiella Infections , Klebsiella pneumoniae , Sialic Acid Binding Immunoglobulin-like Lectins , Klebsiella pneumoniae/immunology , Klebsiella pneumoniae/metabolism , Humans , Sialic Acid Binding Immunoglobulin-like Lectins/metabolism , Sialic Acid Binding Immunoglobulin-like Lectins/immunology , Galectins/metabolism , Galectins/immunology , Klebsiella Infections/immunology , Klebsiella Infections/microbiology , Bacterial Capsules/immunology , Bacterial Capsules/metabolism , Lectins/metabolism , Lectins/immunology , Protein Binding
4.
Expert Opin Ther Targets ; 28(7): 587-600, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38965991

ABSTRACT

BACKGROUND: Psoriasis is a chronic immune-mediated skin condition with several types of manifestation, including psoriatic arthritis. In recent years, studies have demonstrated multiple molecules and mechanisms that play important roles in the pathophysiology of psoriasis. Studies have been conducted to determine the role of adipokines, bioactive peptides secreted by the adipose tissue, in the pathogenesis of inflammatory diseases. These studies have shown that adipokines are dysregulated in psoriasis and their abnormal expression profile could contribute to the inflammatory mechanisms observed in psoriasis. AREAS COVERED: In this review, we discuss the immunomodulatory features of resistin, omentin-1, and vaspin, and discuss their potential involvement in the pathogenesis of psoriasis. EXPERT OPINION: The adipokines resistin, omentin, and vaspin appear to be promising therapeutic targets in psoriasis. It is important to seek to block the action of resistin, either by blocking its receptors or by blocking its systemic effects with antibodies. In the case of omentin and vaspin, substances that are receptor mimetics of these adipokines should be sought and studies conducted of their analogues for the treatment of psoriasis. To introduce these therapies into clinical practice, multicentre clinical trials are required to confirm their efficacy and safety after initial studies in animal models.


Subject(s)
Cytokines , GPI-Linked Proteins , Lectins , Psoriasis , Resistin , Serpins , Humans , Psoriasis/drug therapy , GPI-Linked Proteins/metabolism , Serpins/pharmacology , Serpins/metabolism , Animals , Cytokines/metabolism , Resistin/metabolism , Adipokines/metabolism
5.
Int J Biol Macromol ; 275(Pt 2): 133664, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38969035

ABSTRACT

Lectins are proteins or glycoproteins of non-immune origin with carbohydrate-binding properties. They are found both prokaryotic and eukaryotic organisms. The most abundant source of the lectins are plants. Many lectins have anticancer effects by directly exerting cytotoxic effects on malignant cells or indirectly activating the immune system. Lectins also have antiviral activities. These proteins can recognise glycoproteins on the surface of enveloped viruses and bind to them. This creates a physical barrier between them and the corresponding receptors on the surface of the host cell, which prevents the virus from entering the cell and can thus effectively inhibit the replication of the virus. In this review, we focus on the anticancer activities of selected lectins and the underlying mechanisms. We also discuss different types of lectins with antiviral activity. We have paid special attention to lectins with inhibitory activity against SARS-CoV-2. Finally, we outline the challenges of using lectins in therapy and suggest future research directions.


Subject(s)
Antineoplastic Agents , Antiviral Agents , COVID-19 Drug Treatment , Lectins , SARS-CoV-2 , Humans , SARS-CoV-2/drug effects , Antiviral Agents/pharmacology , Antiviral Agents/chemistry , Antiviral Agents/therapeutic use , Lectins/pharmacology , Lectins/chemistry , Lectins/therapeutic use , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Neoplasms/drug therapy , Neoplasms/metabolism , COVID-19/virology , Animals
6.
Dev Comp Immunol ; 159: 105222, 2024 Oct.
Article in English | MEDLINE | ID: mdl-38964676

ABSTRACT

Invertebrate lectins exhibit structural diversity and play crucial roles in the innate immune responses by recognizing and eliminating pathogens. In the present study, a novel lectin containing a Gal_Lectin, a CUB and a transmembrane domain was identified from the Pacific oyster Crassostrea gigas (defined as CgGal-CUB). CgGal-CUB mRNA was detectable in all the examined tissues with the highest expression in adductor muscle (11.00-fold of that in haemocytes, p < 0.05). The expression level of CgGal-CUB mRNA in haemocytes was significantly up-regulated at 3, 24, 48 and 72 h (8.37-fold, 12.13-fold, 4.28-fold and 10.14-fold of that in the control group, respectively) after Vibrio splendidus stimulation. The recombinant CgGal-CUB (rCgGal-CUB) displayed binding capability to Mannan (MAN), peptidoglycan (PGN), D-(+)-Galactose and L-Rhamnose monohydrate, as well as Gram-negative bacteria (Escherichia coli, V. splendidus and Vibrio anguillarum), Gram-positive bacteria (Micrococcus luteus, Staphylococcus aureus, and Bacillus sybtilis) and fungus (Pichia pastoris). rCgGal-CUB was also able to agglutinate V. splendidus, and inhibit V. splendidus growth. Furthermore, rCgGal-CUB exhibited the activities of enhancing the haemocyte phagocytosis towards V. splendidus, and the phagocytosis rate of haemocytes was descended in blockage assay with CgGal-CUB antibody. These results suggested that CgGal-CUB served as a pattern recognition receptor to bind various PAMPs and bacteria, and enhanced the haemocyte phagocytosis towards V. splendidus.


Subject(s)
Crassostrea , Hemocytes , Immunity, Innate , Lectins , Phagocytosis , Vibrio , Animals , Hemocytes/immunology , Hemocytes/metabolism , Crassostrea/immunology , Vibrio/immunology , Vibrio/physiology , Lectins/metabolism , Lectins/genetics , Lectins/immunology , Mannans/metabolism , Mannans/immunology , Protein Domains/genetics , Peptidoglycan/immunology , Peptidoglycan/metabolism , Galactose/metabolism , Galactose/immunology , Vibrio Infections/immunology
7.
J Transl Med ; 22(1): 674, 2024 Jul 22.
Article in English | MEDLINE | ID: mdl-39039496

ABSTRACT

BACKGROUND: Preeclampsia, especially early-onset preeclampsia (EO-PE), is a pregnancy complication that has serious consequences for the health of both the mother and the fetus. Although abnormal placentation due to mitochondrial dysfunction is speculated to contribute to the development of EO-PE, the underlying mechanisms have yet to be fully elucidated. METHODS: The expression and localization of Siglec-6 in the placenta from normal pregnancies, preterm birth and EO-PE patients were examined by RT-qPCR, Western blot and IHC. Transwell assays were performed to evaluate the effect of Siglec-6 on trophoblast cell migration and invasion. Seahorse experiments were conducted to assess the impact of disrupting Siglec-6 expression on mitochondrial function. Co-IP assay was used to examine the interaction of Siglec-6 with SHP1/SHP2. RNA-seq was employed to investigate the mechanism by which Siglec-6 inhibits mitochondrial function in trophoblast cells. RESULTS: The expression of Siglec-6 in extravillous trophoblasts is increased in placental tissues from EO-PE patients. Siglec-6 inhibits trophoblast cell migration and invasion and impairs mitochondrial function. Mechanismly, Siglec-6 inhibits the activation of NF-κB by recruiting SHP1/SHP2, leading to increased expression of GPR20. Notably, the importance of GPR20 function downstream of Siglec-6 in trophoblasts is supported by the observation that GPR20 downregulation rescues defects caused by Siglec-6 overexpression. Finally, overexpression of Siglec-6 in the placenta induces a preeclampsia-like phenotype in a pregnant mouse model. CONCLUSIONS: This study indicates that the regulatory pathway Siglec-6/GPR20 has a crucial role in regulating trophoblast mitochondrial function, and we suggest that Siglec-6 and GPR20 could serve as potential markers and targets for the clinical diagnosis and therapy of EO-PE.


Subject(s)
Cell Movement , Mitochondria , Pre-Eclampsia , Receptors, G-Protein-Coupled , Trophoblasts , Up-Regulation , Pre-Eclampsia/metabolism , Pre-Eclampsia/genetics , Pre-Eclampsia/pathology , Humans , Pregnancy , Female , Mitochondria/metabolism , Up-Regulation/genetics , Trophoblasts/metabolism , Animals , Receptors, G-Protein-Coupled/metabolism , Receptors, G-Protein-Coupled/genetics , Cell Movement/genetics , Lectins/metabolism , Placenta/metabolism , Mice , Antigens, Differentiation, Myelomonocytic/metabolism , Antigens, CD/metabolism , Antigens, Differentiation, B-Lymphocyte/metabolism , Antigens, Differentiation, B-Lymphocyte/genetics , Adult
8.
Chem Biol Interact ; 399: 111156, 2024 Aug 25.
Article in English | MEDLINE | ID: mdl-39029856

ABSTRACT

Leishmaniases, caused by Leishmania parasites, are widespread and pose significant health risks globally. Visceral leishmaniasis (VL) is particularly prevalent in Brazil, with high morbidity and mortality rates. Traditional treatments, such as pentavalent antimonials, have limitations due to toxicity and resistance. Therefore, exploring new compounds like lectins is crucial. Concanavalin A (ConA) has shown promise in inhibiting Leishmania growth. This study aimed to evaluate its leishmanicidal effect on L. infantum promastigotes and understand its mechanism of action. In vitro tests demonstrated inhibition of promastigote growth when treated with ConA, with IC50 values ranging from 3 to 5 µM over 24-72 h. This study suggests that ConA interacts with L. infantum glycans. Additionally, ConA caused damage to the membrane integrity of parasites and induced ROS production, contributing to parasite death. Scanning electron microscopy confirmed morphological alterations in treated promastigotes. ConA combined with the amphotericin B (AmB) showed synergistic effects, reducing the required dose of AmB, and potentially mitigating its toxicity. ConA demonstrated no cytotoxic effects on macrophages, instead stimulating their proliferation. These findings reinforce that lectin exhibits promising leishmanicidal activity against L. infantum promastigotes, making ConA a potential candidate for leishmaniasis treatment.


Subject(s)
Antiprotozoal Agents , Canavalia , Concanavalin A , Leishmania infantum , Leishmania infantum/drug effects , Concanavalin A/pharmacology , Animals , Antiprotozoal Agents/pharmacology , Antiprotozoal Agents/chemistry , Seeds/chemistry , Reactive Oxygen Species/metabolism , Mice , Amphotericin B/pharmacology , Lectins/pharmacology , Lectins/chemistry , Lectins/metabolism , Plant Lectins/pharmacology , Plant Lectins/chemistry , Macrophages/drug effects , Macrophages/metabolism , Macrophages/parasitology
9.
Mar Drugs ; 22(7)2024 Jun 30.
Article in English | MEDLINE | ID: mdl-39057416

ABSTRACT

Oncolytic virotherapy is expected to provide a new treatment strategy for cancer. Aphrocallistes vastus lectin (AVL) is a Ca2+-dependent lectin receptor containing the conserved domain of C-type lectin and the hydrophobic N-terminal region, which can bind to the bird's nest glycoprotein and D-galactose. Our previous studies suggested that the oncolytic vaccinia virus (oncoVV) armed with the AVL gene exerted remarkable replication and antitumor effects in vitro and in vivo. In this study, we found that oncoVV-AVL may reprogram the metabolism of hepatocellular carcinoma cells to promote ROS, and elevated ROS subsequently promoted viral replication and induced apoptosis. This study will provide a new theoretical basis for the application of oncoVV-AVL in liver cancer.


Subject(s)
Apoptosis , Carcinoma, Hepatocellular , Lectins , Liver Neoplasms , Oncolytic Virotherapy , Oncolytic Viruses , Reactive Oxygen Species , Vaccinia virus , Virus Replication , Humans , Apoptosis/drug effects , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/therapy , Cell Line, Tumor , Lectins/pharmacology , Liver Neoplasms/drug therapy , Oncolytic Virotherapy/methods , Reactive Oxygen Species/metabolism , Vaccinia virus/drug effects , Virus Replication/drug effects , Animals , Porifera
10.
Anal Chim Acta ; 1316: 342819, 2024 Aug 08.
Article in English | MEDLINE | ID: mdl-38969421

ABSTRACT

BACKGROUND: Exosomes, as emerging biomarkers in liquid biopsies in recent years, offer profound insights into cancer diagnostics due to their unique molecular signatures. The glycosylation profiles of exosomes have emerged as potential biomarkers, offering a novel and less invasive method for cancer diagnosis and monitoring. Colorectal cancer (CRC) represents a substantial global health challenge and burden. Thus there is a great need for the aberrant glycosylation patterns on the surface of CRC cell-derived exosomes, proposing them as potential biomarkers for tumor characterization. RESULTS: The interactions of 27 lectins with exosomes from three CRC cell lines (SW480, SW620, HCT116) and one normal colon epithelial cell line (NCM460) have been analyzed by the lectin microarray. The result indicates that Ulex Europaeus Agglutinin I (UEA-I) exhibits high affinity and specificity towards exosomes derived from SW480 cells. The expression of glycosylation related genes within cells has been analyzed by high-throughput quantitative polymerase chain reaction (HT-qPCR). The experimental result of HT-qPCR is consistent with that of lectin microarray. Moreover, the limit of detection (LOD) of UEA-I microarray is calculated to be as low as 2.7 × 105 extracellular vehicles (EVs) mL-1 (three times standard deviation (3σ) of blank sample). The UEA-I microarray has been successfully utilized to dynamically monitor the progression of tumors in mice-bearing SW480 CRC subtype, applicable in tumor sizes ranging from 2 mm to 20 mm in diameter. SIGNIFICANCE: The results reveal that glycan expression pattern of exosome is linked to specific CRC subtypes, and regulated by glycosyltransferase and glycosidase genes of mother cells. Our findings illuminate the potential of glycosylation molecules on the surface of exosomes as reliable biomarkers for diagnosis of tumor at early stage and monitoring of cancer progression.


Subject(s)
Colorectal Neoplasms , Exosomes , Lectins , Polysaccharides , Exosomes/metabolism , Exosomes/chemistry , Colorectal Neoplasms/metabolism , Colorectal Neoplasms/pathology , Colorectal Neoplasms/diagnosis , Humans , Polysaccharides/metabolism , Polysaccharides/chemistry , Animals , Lectins/metabolism , Lectins/chemistry , Mice , Disease Progression , Cell Line, Tumor , Biomarkers, Tumor/metabolism
11.
Libyan J Med ; 19(1): 2383025, 2024 Dec 31.
Article in English | MEDLINE | ID: mdl-39042809

ABSTRACT

To explore the relationship between serum levels of midkine and omentin-1 and the severity of sepsis in patients, and their prognostic value. A retrospective analysis was conducted on the clinical data of 180 sepsis patients. According to the severity of the patient's condition, they were separated into sepsis group (n = 76), severe sepsis group (n = 59), and sepsis shock group (n = 45). Based on the survival within 28 days of admission, they were grouped into survivors group (n = 128) and nonsurvivors group (n = 52). The serum Midkine level and APACHE II score in the sepsis shock group were higher than those in the severe sepsis group and sepsis group, while the Omentin-1 level was lower than that in the severe sepsis group and sepsis group (p < 0.05). The serum Midkine level and APACHE II score in the severe sepsis group were higher than those in the sepsis group, while the Omentin-1 level was lower than that in the sepsis group (p < 0.05). The Midkine and APACHE II score in the nonsurvivors group was higher than those in the survivors group, while the Omentin-1 score was lower than that in the survivors group (p < 0.05). Midkine and APACHE II score were independent risk factors for the prognosis of sepsis patients, while Omentin-1 was a protective factor for the prognosis of sepsis patients (p < 0.05). The AUC of the combined prediction of serum Midkine and Ommentin-1 for the prognosis of sepsis patients was 0.880, with a sensitivity of 90.38% and a specificity of 72.66%. The combined prediction of serum Midkine and Ommentin-1 was better than that of individual prediction of Midkine and Ommentin-1. Serum Midkine is highly expressed and Omentin-1 is lowly expressed in sepsis patients, and the combination of the two has a high predictive power for the prognosis of sepsis patients.


Subject(s)
APACHE , Cytokines , GPI-Linked Proteins , Lectins , Midkine , Sepsis , Severity of Illness Index , Humans , Lectins/blood , GPI-Linked Proteins/blood , Cytokines/blood , Midkine/blood , Male , Female , Sepsis/blood , Sepsis/mortality , Prognosis , Middle Aged , Retrospective Studies , Aged , Biomarkers/blood , Adult , ROC Curve
12.
J Vis Exp ; (208)2024 Jun 28.
Article in English | MEDLINE | ID: mdl-39007607

ABSTRACT

Protein glycosylation, a critical post-translational modification, influences the stability, efficacy, and immunogenicity of recombinant proteins, including biopharmaceuticals. Glycan structures exhibit significant heterogeneity, varying with production cell types, culture conditions, and purification methods. Consequently, monitoring and evaluating the glycan structures of recombinant proteins is vital, particularly in biopharmaceutical production. The lectin microarray, a technique complementary to mass spectrometry, boasts high sensitivity and ease of use. However, it typically requires more than a day to yield results. To adapt it to non-glycoscience research or drug product process development, an automated, high-throughput alternative is needed. Therefore, the world's first fully automated lectin-based glycan profiling system was developed, utilizing the "bead array in a single tip (BIST)" technology concept. This system allows for the preparation and storage of lectin-immobilized beads in units of 1,000, with customizable parallel insertion orders for various purposes. This article presents a practical protocol for research involving "glyco-qualified" recombinant proteins. After testing their reactivity against 12 polyacrylamide-glycan conjugates, 15 lectins were selected to increase the system's versatility. In addition, the sample labeling process was optimized by switching from Cy3 to biotin, reducing the overall processing time by 30 min. For immediate data qualification, lectin-binding signals are displayed as a dotcode on the top monitor. The system's reliability was confirmed through day-to-day reproducibility tests, repeatability tests, and long-term storage tests, with a coefficient of variation of <10%. This user-friendly and rapid glyco-analyzer has potential applications in the quality monitoring of endogenous glycoproteins for biomarker evaluation and validation. This method facilitates analysis for those new to glycoscience, thereby broadening its practical utility.


Subject(s)
Lectins , Polysaccharides , Recombinant Proteins , Recombinant Proteins/chemistry , Polysaccharides/chemistry , Polysaccharides/analysis , Lectins/chemistry , Glycosylation , Automation, Laboratory/methods
13.
Nanoscale ; 16(29): 13962-13978, 2024 Jul 25.
Article in English | MEDLINE | ID: mdl-38984502

ABSTRACT

Multivalent lectin-glycan interactions (MLGIs) are pivotal for viral infections and immune regulation. Their structural and biophysical data are thus highly valuable, not only for understanding their basic mechanisms but also for designing potent glycoconjugate therapeutics against target MLGIs. However, such information for some important MGLIs remains poorly understood, greatly limiting research progress. We have recently developed densely glycosylated nanoparticles, e.g., ∼4 nm quantum dots (QDs) or ∼5 nm gold nanoparticles (GNPs), as mechanistic probes for MLGIs. Using two important model lectin viral receptors, DC-SIGN and DC-SIGNR, we have shown that these probes can not only offer sensitive fluorescence assays for quantifying MLGI affinities, but also reveal key structural information (e.g., binding site orientation and binding mode) useful for MLGI targeting. However, the small sizes of the previous scaffolds may not be optimal for maximising MLGI affinity and targeting specificity. Herein, using α-manno-α-1,2-biose (DiMan) functionalised GNP (GNP-DiMan) probes, we have systematically studied how GNP scaffold size (e.g., 5, 13, and 27 nm) and glycan density (e.g., 100, 75, 50 and 25%) determine their MLGI affinities, thermodynamics, and antiviral properties. We have developed a new GNP fluorescence quenching assay format to minimise the possible interference of GNP's strong inner filter effect in MLGI affinity quantification, revealing that increasing the GNP size is highly beneficial for enhancing MLGI affinity. We have further determined the MLGI thermodynamics by combining temperature-dependent affinity and Van't Hoff analyses, revealing that GNP-DiMan-DC-SIGN/R binding is enthalpy driven with favourable binding Gibbs free energy changes (ΔG°) being enhanced with increasing GNP size. Finally, we show that increasing the GNP size significantly enhances their antiviral potency. Notably, the DiMan coated 27 nm GNP potently and robustly blocks both DC-SIGN and DC-SIGNR mediated pseudo-Ebola virus cellular entry with an EC50 of ∼23 and ∼49 pM, respectively, making it the most potent glycoconjugate inhibitor against DC-SIGN/R-mediated Ebola cellular infections. Our results have established GNP-glycans as a new tool for quantifying MLGI biophysical parameters and revealed that increasing the GNP scaffold size significantly enhances their MLGI affinities and antiviral potencies.


Subject(s)
Antiviral Agents , Gold , Metal Nanoparticles , Polysaccharides , Thermodynamics , Gold/chemistry , Metal Nanoparticles/chemistry , Humans , Antiviral Agents/chemistry , Antiviral Agents/pharmacology , Polysaccharides/chemistry , Lectins, C-Type/metabolism , Lectins, C-Type/chemistry , Cell Adhesion Molecules/metabolism , Cell Adhesion Molecules/chemistry , Receptors, Cell Surface/metabolism , Receptors, Cell Surface/chemistry , Lectins/chemistry , Lectins/metabolism
14.
Bioconjug Chem ; 35(8): 1200-1206, 2024 Aug 21.
Article in English | MEDLINE | ID: mdl-38982902

ABSTRACT

Glycoamphiphiles have attracted considerable interest in a broad range of application fields owing to their solution and bulk-state self-assembly abilities. Despite their importance, the straightforward synthesis of glycoamphiphiles consisting of a hydrophilic carbohydrate linked to a hydrophobic aglycone remains one of the major challenges in glycosciences. Here, a rapid, simple, and efficient synthetic access to chemically stable glycoamphiphiles at physiological pH, namely, N-(ß-d-glycosyl)-2-alkylbenzamide, is reported. It leverages the nonreductive amination of unprotected carbohydrates with ortho-substituted aniline derivatives which could be readily obtained by reacting commercially available primary alkylamines with isatoic anhydride. This strategy avoids protection and deprotection of sugar hydroxyl groups and the use of reductive agents, which makes it advantageous in terms of atom and step economy. Moreover, in order to circumvent the cons of classical N-aryl glycosylation, we investigate the use of microwave as a heat source that provides fast, clean, and high-yield ß-N-arylation of unprotected carbohydrates. Their self-assembly into water led to multiple morphologies of dynamic supramolecular glycoamphiphiles that were characterized to assess their ability to bind to lectins from pathogenic bacteria. Biophysical interactions probed by isothermal titration microcalorimetry revealed micromolar affinities for most of the synthesized glycoamphiphiles.


Subject(s)
Lectins , Microwaves , Lectins/chemistry , Glycosylation , Carbohydrates/chemistry
15.
mBio ; 15(8): e0110724, 2024 Aug 14.
Article in English | MEDLINE | ID: mdl-39041817

ABSTRACT

Neisserial adhesin A (NadA) is a meningococcal surface protein included as recombinant antigen in 4CMenB, a protein-based vaccine able to induce protective immune responses against Neisseria meningitidis serogroup B (MenB). Although NadA is involved in the adhesion/invasion of epithelial cells and human myeloid cells, its function in meningococcal physiology is still poorly understood. To clarify the role played by NadA in the host-pathogen interaction, we sought to identify its cellular receptors. We screened a protein microarray encompassing 2,846 human and 297 mouse surface/secreted recombinant proteins using recombinant NadA as probe. Efficient NadA binding was revealed on the paired sialic acid-binding immunoglobulin-type lectins receptors 5 and 14 (Siglec-5 and Siglec-14), but not on Siglec-9 therein used as control. The interaction was confirmed by biochemical tools with the determination of the KD value in the order of nanomolar and the identification of the NadA binding site by hydrogen-deuterium exchange coupled to mass spectrometry. The N-terminal domain of the Siglec-5 that recognizes the sialic acid was identified as the NadA binding domain. Intriguingly, exogenously added recombinant soluble Siglecs, including Siglec-9, were found to decorate N. meningitidis surface in a NadA-dependent manner. However, Siglec-5 and Siglec-14 transiently expressed in CHO-K1 cells endorsed NadA binding and increased N. meningitidis adhesion/invasion while Siglec-9 did not. Taken together, Siglec-5 and Siglec-14 satisfy all features of NadA receptors suggesting a possible role of NadA in the acute meningococcal infection.IMPORTANCEBacteria have developed several strategies for cell colonization and immune evasion. Knowledge of the host and pathogen factors involved in these mechanisms is crucial to build efficacious countermoves. Neisserial adhesin A (NadA) is a meningococcal surface protein included in the anti-meningococcus B vaccine 4CMenB, which mediates adhesion to and invasion of epithelial cells. Although NadA has been shown to bind to other cell types, like myeloid and endothelial cells, it still remains orphan of a defined host receptor. We have identified two strong NadA interactors, Siglec-5 and Siglec-14, which are mainly expressed on myeloid cells. This showcases that NadA is an additional and key player among the Neisseria meningitidis factors targeting immune cells. We thus provide novel insights on the strategies exploited by N. meningitidis during the infection process, which can progress to a severe illness and death.


Subject(s)
Adhesins, Bacterial , Antigens, CD , Antigens, Differentiation, Myelomonocytic , Bacterial Adhesion , Host-Pathogen Interactions , Lectins , Humans , Adhesins, Bacterial/metabolism , Adhesins, Bacterial/genetics , Antigens, CD/metabolism , Antigens, CD/genetics , Lectins/metabolism , Lectins/genetics , Lectins/immunology , Animals , Antigens, Differentiation, Myelomonocytic/metabolism , Antigens, Differentiation, Myelomonocytic/genetics , Protein Binding , Mice , CHO Cells , Cricetulus , Neisseria meningitidis/genetics , Neisseria meningitidis/metabolism , Neisseria meningitidis/immunology , Recombinant Proteins/metabolism , Recombinant Proteins/genetics , Sialic Acid Binding Immunoglobulin-like Lectins/metabolism , Sialic Acid Binding Immunoglobulin-like Lectins/genetics , Epithelial Cells/microbiology , Epithelial Cells/metabolism , Epithelial Cells/immunology , Meningococcal Infections/microbiology , Meningococcal Infections/immunology , Receptors, Cell Surface/metabolism , Receptors, Cell Surface/genetics , Neisseria meningitidis, Serogroup B/genetics , Neisseria meningitidis, Serogroup B/immunology , Neisseria meningitidis, Serogroup B/metabolism
16.
Clin Chim Acta ; 562: 119838, 2024 Aug 15.
Article in English | MEDLINE | ID: mdl-38972537

ABSTRACT

Breast cancer (BC) is the most frequently diagnosed cancer and a leading cause of cancer-related mortality among women globally. Resistin, omentin and ghrelin, adipokines involved in inflammation and metabolic regulation, have been implicated in cancer development, yet their associations with BC remain unclear. This systematic review and meta-analysis aimed to elucidate the relationships between resistin, omentin, and ghrelin concentrations and BC, while exploring potential moderators such as body mass index (BMI) and menopausal status. A comprehensive search of electronic databases up to 13 May 2024 identified studies comparing resistin and omentin, but not ghrelin, concentrations in BC patients and healthy controls. Standardized mean differences (SMDs) were calculated using random-effects models, and meta-regression and subgroup analyses were performed to investigate sources of heterogeneity. Analysis of 11 studies showed that BC patients exhibited significantly higher resistin concentrations compared to controls, with a pooled SMD of 2.05 (95 % CI 1.24 to 2.86, p < 0.001). Meta-regression indicated that BMI significantly moderated the resistin-BC association (p = 0.003). In contrast, omentin concentrations presented a complex picture, with a pooled SMD of -0.27 (95 % CI -1.39 to 0.84, I^2 = 96.2 %, p < 0.001), indicating substantial heterogeneity and inconclusive results, whereas only one study investigated ghrelin. Our findings support a significant association between elevated resistin concentrations and BC, suggesting a potential role of resistin in BC pathophysiology. The data on omentin and ghrelin remain inconclusive, warranting further investigation. Future research should focus on large, longitudinal studies with standardized methodologies to validate these findings and clarify the role of adipokines in BC.


Subject(s)
Breast Neoplasms , Cytokines , GPI-Linked Proteins , Lectins , Resistin , Humans , Resistin/blood , Breast Neoplasms/blood , Breast Neoplasms/metabolism , Lectins/blood , GPI-Linked Proteins/blood , Cytokines/blood , Female , Ghrelin/blood
17.
Nutrients ; 16(14)2024 Jul 16.
Article in English | MEDLINE | ID: mdl-39064727

ABSTRACT

Gymnema sylvestre (GS) and berberine (BBR) are natural products that have demonstrated therapeutic potential for the management of obesity and its comorbidities, as effective and safe alternatives to synthetic drugs. Although their anti-obesogenic and antidiabetic properties have been widely studied, comparative research on their impact on the gene expression of adipokines, such as resistin (Res), omentin (Ome), visfatin (Vis) and apelin (Ap), has not been reported. METHODOLOGY: We performed a comparative study in 50 adult Mexican patients with obesity treated with GS or BBR for 3 months. The baseline and final biochemical parameters, body composition, blood pressure, gene expression of Res, Ome, Vis, and Ap, and safety parameters were evaluated. RESULTS: BBR significantly decreased (p < 0.05) body weight, blood pressure and Vis and Ap gene expression and increased Ome, while GS decreased fasting glucose and Res gene expression (p < 0.05). A comparative analysis of the final measurements revealed a lower gene expression of Ap and Vis (p < 0.05) in patients treated with BBR than in those treated with GS. The most frequent adverse effects in both groups were gastrointestinal symptoms, which attenuated during the first month of treatment. CONCLUSION: In patients with obesity, BBR has a better effect on body composition, blood pressure, and the gene expression of adipokines related to metabolic risk, while GS has a better effect on fasting glucose and adipokines related to insulin resistance, with minimal side effects.


Subject(s)
Adipokines , Berberine , Body Composition , Gymnema sylvestre , Obesity , Resistin , Humans , Male , Female , Adult , Obesity/drug therapy , Obesity/metabolism , Adipokines/blood , Adipokines/metabolism , Body Composition/drug effects , Middle Aged , Berberine/pharmacology , Resistin/blood , Resistin/metabolism , Apelin , Blood Pressure/drug effects , Nicotinamide Phosphoribosyltransferase/metabolism , Cytokines/metabolism , Cytokines/blood , Plant Extracts/pharmacology , Blood Glucose/drug effects , Blood Glucose/metabolism , Lectins , GPI-Linked Proteins/metabolism , GPI-Linked Proteins/genetics , Anti-Obesity Agents/pharmacology , Anti-Obesity Agents/therapeutic use
18.
Biochem Biophys Res Commun ; 730: 150355, 2024 Oct 20.
Article in English | MEDLINE | ID: mdl-38996784

ABSTRACT

Aphrocallistes vastus lectin (AVL) is a Ca2+ dependent C-type lectin produced by sponges. Previous studies have demonstrated that oncolytic vaccinia virus harboring AVL (oncoVV-AVL) effectively triggers cell death in various tumors. However, the effects of oncoVV-AVL on human ovarian cancer (OV) remain unknown. This study aims to investigate the mechanism-of-action of oncoVV-AVL in human OV cell lines and in tumor-bearing nude mice. We found that oncoVV-AVL could directly induce apoptosis and autophagy in ovarian cancer cells. Additionally, our results showed that oncoVV-AVL increased the serum levels of mouse IFN-γ (mIFN-γ), leading to the activation of M1-polarized macrophages. Conversely, NADPH, a reducing agent by providing reducing equivalents, reduced the production of mIFN-γ, and suppressed M1-polarization of macrophage. Based on these findings, we propose that oncoVV-AVL not only contributes to direct cytolysis, but also enhances host immune response by promoting ROS levels.


Subject(s)
Mice, Nude , Oncolytic Virotherapy , Oncolytic Viruses , Ovarian Neoplasms , Reactive Oxygen Species , Vaccinia virus , Humans , Animals , Female , Ovarian Neoplasms/immunology , Ovarian Neoplasms/therapy , Ovarian Neoplasms/drug therapy , Ovarian Neoplasms/pathology , Oncolytic Virotherapy/methods , Mice , Reactive Oxygen Species/metabolism , Cell Line, Tumor , Interferon-gamma/metabolism , Mice, Inbred BALB C , Apoptosis/drug effects , Lectins/pharmacology
19.
Breast Dis ; 43(1): 193-211, 2024.
Article in English | MEDLINE | ID: mdl-38905027

ABSTRACT

Efficient treatment of cancer has been a subject of research by scientists for many years. Current treatments for cancer, such as radiotherapy, chemotherapy and surgery have been used in traditional combination therapy, but they have major setbacks like non-specificity, non-responsiveness in certain cancer types towards treatment, tumor recurrence, etc. Epidemiological data has shown that breast cancer accounts for 14% of cancer cases occurring in Indian women. In recent years, scientists have started to focus on the use of natural compounds like lectins obtained from various sources to counter the side effects of traditional therapy. Lectins like Sambucus nigra Agglutinin, Maackia amurensis lectin, Okra lectins, Haliclona caerulea lectin, Sclerotium rolfsii lectin, etc., have been discovered to have both diagnostic and therapeutic potential for breast cancer patients. Lectins have been found to have inhibitory effects on various cancer cell activities such as neo-angiogenesis, causing cell cycle arrest at the G1 phase, and inducing apoptosis. The major idea behind the use of lectins in cancer diagnostics and therapeutics is their capability to bind to glycosylated proteins that are expressed on the cell surface. This review focuses on an exploration of the roles of post-translational modification in cancer cells, especially glycosylation, and the potential of lectins in cancer diagnosis and therapeutics.


Subject(s)
Breast Neoplasms , Lectins , Humans , Breast Neoplasms/drug therapy , Female , Glycosylation , Antineoplastic Agents/therapeutic use , Apoptosis/drug effects , Protein Processing, Post-Translational
20.
Int J Biol Macromol ; 275(Pt 1): 133311, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38909728

ABSTRACT

Lectins are proteins that bind specifically and reversibly to carbohydrates, and some of them have significant anti-tumor activities. Compared to those of lectins from land plants, there are far fewer studies on algal lectins, despite of the high biodiversity of algae. However, canonical strategies based on chromatographic feature-oriented screening cannot satisfy the requirement for algal lectin discovery. In this study, prospecting for novel OAAH family lectins throughout 358 genomes of red algae and cyanobacteria was conducted. Then 35 candidate lectins and 1843 of their simulated mutated forms were virtually screened based on predicted binding specificities to characteristic carbohydrates on cancer cells inferred by a deep learning model. A new lectin, named Siye, was discovered in Kappaphycus alvarezii genome and further verified on different cancer cells. Without causing agglutination of erythrocytes, Siye showed significant cytotoxicity to four human cancer cell lines (IC50 values ranging from 0.11 to 3.95 µg/mL), including breast adenocarcinoma HCC1937, lung carcinoma A549, liver cancer HepG2 and romyelocytic leukemia HL60. And the cytotoxicity was induced through promoting apoptosis by regulating the caspase and the p53 pathway within 24 h. This study testifies the feasibility and efficiency of the genome mining guided by evolutionary theory and artificial intelligence in the discovery of algal lectins.


Subject(s)
Antineoplastic Agents , Computer Simulation , Rhodophyta , Humans , Rhodophyta/chemistry , Rhodophyta/genetics , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Lectins/pharmacology , Lectins/chemistry , Lectins/genetics , Lectins/metabolism , Apoptosis/drug effects , Cell Line, Tumor , Genome , Edible Seaweeds
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