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1.
Front Immunol ; 13: 868496, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35720315

RESUMO

Natural killer (NK) cell responses depend on the balance of signals from inhibitory and activating receptors. However, how the integration of antagonistic signals occurs upon NK cell-target cell interaction is not fully understood. Here we provide evidence that NK cell inhibition via the inhibitory receptor Ly49A is dependent on its relative colocalization at the nanometer scale with the activating receptor NKG2D upon immune synapse (IS) formation. NKG2D and Ly49A signal integration and colocalization were studied using NKG2D-GFP and Ly49A-RFP-expressing primary NK cells, forming ISs with NIH3T3 target cells, with or without the expression of single-chain trimer (SCT) H2-Dd and an extended form of SCT H2-Dd-CD4 MHC-I molecules. Nanoscale colocalization was assessed by Förster resonance energy transfer between NKG2D-GFP and Ly49A-RFP and measured for each synapse. In the presence of their respective cognate ligands, NKG2D and Ly49A colocalize at the nanometer scale, leading to NK cell inhibition. However, increasing the size of the Ly49A ligand reduced the nanoscale colocalization with NKG2D, consequently impairing Ly49A-mediated inhibition. Thus, our data shows that NK cell signal integration is critically dependent on the dimensions of NK cell ligand-receptor pairs by affecting their relative nanometer-scale colocalization at the IS. Our results together suggest that the balance of NK cell signals and NK cell responses is determined by the relative nanoscale colocalization of activating and inhibitory receptors in the immune synapse.


Assuntos
Subfamília A de Receptores Semelhantes a Lectina de Células NK , Subfamília K de Receptores Semelhantes a Lectina de Células NK , Animais , Proteínas de Transporte/metabolismo , Antígenos H-2 , Antígeno de Histocompatibilidade H-2D/metabolismo , Células Matadoras Naturais , Lectinas Tipo C/metabolismo , Ligantes , Camundongos , Células NIH 3T3 , Subfamília A de Receptores Semelhantes a Lectina de Células NK/metabolismo , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Receptores Semelhantes a Lectina de Células NK/metabolismo , Receptores de Células Matadoras Naturais/metabolismo
2.
Microbiome ; 10(1): 91, 2022 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-35698210

RESUMO

BACKGROUND: Innate immunity genes have been reported to affect susceptibility to inflammatory bowel diseases (IBDs) and colitis in mice. Dectin-1, a receptor for fungal cell wall ß-glucans, has been clearly implicated in gut microbiota modulation and modification of the susceptibility to gut inflammation. Here, we explored the role of Dectin-1 and Dectin-2 (another receptor for fungal cell wall molecules) deficiency in intestinal inflammation. DESIGN: Susceptibility to dextran sodium sulfate (DSS)-induced colitis was assessed in wild-type, Dectin-1 knockout (KO), Dectin-2KO, and double Dectin-1KO and Dectin-2KO (D-1/2KO) mice. Inflammation severity, as well as bacterial and fungal microbiota compositions, was monitored. RESULTS: While deletion of Dectin-1 or Dectin-2 did not have a strong effect on DSS-induced colitis, double deletion of Dectin-1 and Dectin-2 significantly protected the mice from colitis. The protection was largely mediated by the gut microbiota, as demonstrated by fecal transfer experiments. Treatment of D-1/2KO mice with opportunistic fungal pathogens or antifungal agents did not affect the protection against gut inflammation, suggesting that the fungal microbiota had no role in the protective phenotype. Amplicon-based microbiota analysis of the fecal bacterial and fungal microbiota of D-1/2KO mice confirmed the absence of changes in the mycobiota but strong modification of the bacterial microbiota. We showed that bacteria from the Lachnospiraceae family were at least partly involved in this protection and that treatment with Blautia hansenii was enough to recapitulate the protection. CONCLUSIONS: Deletion of both the Dectin-1 and Dectin-2 receptors triggered a global shift in the microbial gut environment, affecting, surprisingly, mainly the bacterial population and driving protective effects in colitis. Members of the Lachnospiraceae family seem to play a central role in this protection. These findings provide new insights into the role of the Dectin receptors, which have been described to date as affecting only the fungal population, in intestinal physiopathology and in IBD. Video Abstract.


Assuntos
Colite , Microbioma Gastrointestinal , Micobioma , Animais , Bactérias/genética , Sulfato de Dextrana/efeitos adversos , Modelos Animais de Doenças , Inflamação , Lectinas Tipo C/metabolismo , Camundongos , Camundongos Endogâmicos C57BL
3.
Int J Mol Sci ; 23(11)2022 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-35682991

RESUMO

Despite diagnostic and therapeutic improvements, glioblastoma (GB) remains one of the most threatening brain tumor in adults, underlining the urgent need of new therapeutic targets. Lectins are glycan-binding proteins that regulate several biological processes through the recognition of specific sugar motifs. Lectins and their ligands are found on immune cells, endothelial cells and, also, tumor cells, pointing out a strong correlation among immunity, tumor microenvironment and vascularization. In GB, altered glycans and lectins contribute to tumor progression and immune evasion, shaping the tumor-immune landscape promoting immunosuppressive cell subsets, such as myeloid-derived suppressor cells (MDSCs) and M2-macrophages, and affecting immunoeffector populations, such as CD8+ T cells and dendritic cells (DCs). Here, we discuss the latest knowledge on the immune cells, immune related lectin receptors (C-type lectins, Siglecs, galectins) and changes in glycosylation that are involved in immunosuppressive mechanisms in GB, highlighting their interest as possible novel therapeutical targets.


Assuntos
Glioblastoma , Linfócitos T CD8-Positivos , Células Endoteliais/metabolismo , Galectinas/metabolismo , Humanos , Lectinas Tipo C , Polissacarídeos/metabolismo , Microambiente Tumoral
4.
Mem Inst Oswaldo Cruz ; 117: e220014, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35703715

RESUMO

BACKGROUND: Leprosy, caused by Mycobacterium leprae, is a public health problem in Brazil that affects peripheral nerves, resulting in physical disabilities. During host-pathogen interactions, the immune response determines leprosy outcomes from a localised (paucibacillary) form to a disseminated (multibacillary) form. The recognition of M. leprae involves the DC-SIGN receptor, which is present on the dendritic cells (DCs) and participates in immune activation. OBJECTIVES: To evaluate the association of polymorphisms in the promoter region of the gene encoding DC-SIGN (CD209) and the clinical form of leprosy, and to investigate its functional effects. METHODS: The study population included 406 leprosy patients from an endemic area in Brazil [310 multibacillary (MB); 96 paucibacillary (PB)]. A functional evaluation based on the effects of the single nucleotide variant (SNV) associated with PB leprosy on the specific immune response was also performed. RESULTS: The GA genotype and the presence of the A allele of rs735240 (-939G>A) were associated with PB leprosy [OR: 2.09 (1.18-3.69) and 1.84 (1.07-3.14), respectively]. Carriers of the A allele showed reduced expression of CD209 and TGF-ß1 in leprosy lesions in comparison with individuals with GG genotype, in addition to a higher response to the Mitsuda test. CONCLUSION: These data suggest that rs735240 influences the immune response against M. leprae and clinical presentation of leprosy.


Assuntos
Hanseníase Paucibacilar , Hanseníase , Brasil , Moléculas de Adesão Celular , Humanos , Lectinas Tipo C , Hanseníase/genética , Hanseníase Paucibacilar/genética , Mycobacterium leprae/genética , Receptores de Superfície Celular
5.
Exp Cell Res ; 417(2): 113219, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35643179

RESUMO

Induction of differentiation sensitizes chronic myeloid leukemia (CML) cells to the BCR-ABL inhibitor imatinib by mechanisms that remain unknown. We previously identified the BCR-ABL downstream effector CD69 which inhibits imatinib-induced CML cell differentiation. Herein, we found that the erythroid differentiation inducers activin A and aclacinomycin A induced expression of erythroid markers (α-globin, ζ-globin, GATA-1, and glycophorin A) and simultaneously reduced CD69 levels in K562 CML cells. Blockade of p38MAPK by SB203580 and shRNA eliminated the inhibitory effect of activin A on the promoter, mRNA, and protein levels and positive cell population of CD69. CD69 overexpression inhibited activin A-induced erythroid marker expression. Pretreatment of K562 cells with activin A to induce differentiation followed by a subtoxic concentration of imatinib caused growth inhibition and apoptosis that was reduced by CD69 overexpression. Activin A also reduced the expression of CD69's potential downstream molecule metallothionein 2A (MT2A) via p38MAPK. MT2A-knockdown reduced CD69 inhibition of activin A-induced erythroid marker expression. Furthermore, MT2A-knockdown reduced CD69 inhibition of activin A-imatinib sequential treatment-mediated growth inhibition and apoptosis in K562 and BCR-ABL-expressing CD34+ cells. These results suggest that CD69 inhibits activin A induction of erythroid differentiation-mediated CML cell sensitivity to imatinib via MT2A. Therefore, activin A induction of erythroid differentiation sensitizes BCR-ABL-positive cells to imatinib by downregulating the erythroid differentiation suppressors CD69 and MT2A.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva , Proteínas Quinases p38 Ativadas por Mitógeno , Ativinas , Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Apoptose , Diferenciação Celular , Resistencia a Medicamentos Antineoplásicos , Proteínas de Fusão bcr-abl/metabolismo , Humanos , Mesilato de Imatinib/farmacologia , Células K562 , Lectinas Tipo C/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Metalotioneína , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
6.
BMC Genomics ; 23(1): 420, 2022 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-35659564

RESUMO

BACKGROUND: The group XIV of C-type lectin domain-containing proteins (CTLDcps) is one of the seventeen groups of CTLDcps discovered in mammals and composed by four members: CD93, Clec14A, CD248 and Thrombomodulin, which have shown to be important players in cancer and vascular biology. Although these proteins belong to the same family, their phylogenetic relationship has never been dissected. To resolve their evolution and characterize their protein domain composition we investigated CTLDcp genes in gnathostomes and cyclostomes and, by means of phylogenetic approaches as well as synteny analyses, we inferred an evolutionary scheme that attempts to unravel their evolution in modern vertebrates. RESULTS: Here, we evidenced the paralogy of the group XIV of CTLDcps in gnathostomes and discovered that a gene loss of CD248 and Clec14A occurred in different vertebrate groups, with CD248 being lost due to chromosome disruption in birds, while Clec14A loss in monotremes and marsupials did not involve chromosome rearrangements. Moreover, employing genome annotations of different lampreys as well as one hagfish species, we investigated the origin and evolution of modern group XIV of CTLDcps. Furthermore, we carefully retrieved and annotated gnathostome CTLDcp domains, pointed out important differences in domain composition between gnathostome classes, and assessed codon substitution rate of each domain by analyzing nonsynonymous (Ka) over synonymous (Ks) substitutions using one representative species per gnathostome order. CONCLUSIONS: CTLDcps appeared with the advent of early vertebrates after a whole genome duplication followed by a sporadic tandem duplication. These duplication events gave rise to three CTLDcps in the ancestral vertebrate that underwent further duplications caused by the independent polyploidizations that characterized the evolution of cyclostomes and gnathostomes. Importantly, our analyses of CTLDcps in gnathostomes revealed critical inter-class differences in both extracellular and intracellular domains, which might help the interpretation of experimental results and the understanding of differences between animal models.


Assuntos
Feiticeiras (Peixe) , Lectinas Tipo C , Animais , Evolução Molecular , Feiticeiras (Peixe)/genética , Feiticeiras (Peixe)/metabolismo , Lampreias/genética , Lampreias/metabolismo , Lectinas Tipo C/genética , Mamíferos/metabolismo , Filogenia , Domínios Proteicos , Vertebrados/genética
7.
Front Immunol ; 13: 877027, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35663984

RESUMO

Parasitoids are widespread in natural ecosystems and normally equipped with diverse viral factors to defeat host immune responses. On the other hand, parasitoids can enhance the antibacterial abilities and improve the hypoimmunity traits of parasitized hosts that may encounter pathogenic infections. These adaptive strategies guarantee the survival of parasitoid offspring, yet their underlying mechanisms are poorly understood. Here, we focused on Cotesia vestalis, an endoparasitoid of the diamondback moth Plutella xylostella, and found that C. vestalis parasitization decreases the number of host hemocytes, leading to disruption of the encapsulation reaction. We further found that one bracovirus C-type lectin gene, CvBV_28-1, is highly expressed in the hemocytes of parasitized hosts and participates in suppressing the proliferation rate of host hemocytes, which in turn reduces their population and represses the process of encapsulation. Moreover, CvBV_28-1 presents a classical bacterial clearance ability via the agglutination response in a Ca2+-dependent manner in response to gram-positive bacteria. Our study provides insights into the innovative strategy of a parasitoid-derived viral gene that has dual functions to manipulate host immunity for a successful parasitism.


Assuntos
Mariposas , Polydnaviridae , Vespas , Animais , Ecossistema , Imunidade , Lectinas Tipo C , Polydnaviridae/genética , Proteínas Virais/genética
8.
J Biomed Sci ; 29(1): 43, 2022 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-35717171

RESUMO

BACKGROUND: Human traits, diseases susceptibility, and clinical outcomes vary hugely among individuals. Despite a fundamental understanding of genetic (or environmental) contributions, the detailed mechanisms of how genetic variation impacts molecular or cellular behaviours of a gene, and subsequently leads to such variability remain poorly understood. METHODS: Here, in addition to phenome-wide correlations, we leveraged multiomics to exploit mechanistic links, from genetic polymorphism to protein structural or functional changes and a cross-omics perturbation landscape of a germline variant. RESULTS: We identified a missense cis-acting expression quantitative trait locus in CLEC18A (rs75776403) in which the altered residue (T151→M151) disrupts the lipid-binding ability of the protein domain. The altered allele carriage led to a metabolic and proliferative shift, as well as immune deactivation, therefore determines human anthropometrics (body height), kidney, and hematological traits. CONCLUSIONS: Collectively, we uncovered genetic pleiotropy in human complex traits and diseases via CLEC18A rs75776403-regulated pathways.


Assuntos
Pleiotropia Genética , Polimorfismo Genético , Alelos , Estudo de Associação Genômica Ampla , Humanos , Lectinas Tipo C/genética , Fenótipo , Polimorfismo de Nucleotídeo Único
9.
Nat Commun ; 13(1): 3267, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35672358

RESUMO

The host's gene expression and gene regulatory response to pathogen exposure can be influenced by a combination of the host's genetic background, the type of and exposure time to pathogens. Here we provide a detailed dissection of this using single-cell RNA-sequencing of 1.3M peripheral blood mononuclear cells from 120 individuals, longitudinally exposed to three different pathogens. These analyses indicate that cell-type-specificity is a more prominent factor than pathogen-specificity regarding contexts that affect how genetics influences gene expression (i.e., eQTL) and co-expression (i.e., co-expression QTL). In monocytes, the strongest responder to pathogen stimulations, 71.4% of the genetic variants whose effect on gene expression is influenced by pathogen exposure (i.e., response QTL) also affect the co-expression between genes. This indicates widespread, context-specific changes in gene expression level and its regulation that are driven by genetics. Pathway analysis on the CLEC12A gene that exemplifies cell-type-, exposure-time- and genetic-background-dependent co-expression interactions, shows enrichment of the interferon (IFN) pathway specifically at 3-h post-exposure in monocytes. Similar genetic background-dependent association between IFN activity and CLEC12A co-expression patterns is confirmed in systemic lupus erythematosus by in silico analysis, which implies that CLEC12A might be an IFN-regulated gene. Altogether, this study highlights the importance of context for gaining a better understanding of the mechanisms of gene regulation in health and disease.


Assuntos
Leucócitos Mononucleares , Lúpus Eritematoso Sistêmico , Regulação da Expressão Gênica , Humanos , Lectinas Tipo C/genética , Leucócitos Mononucleares/metabolismo , Lúpus Eritematoso Sistêmico/genética , RNA/metabolismo , Receptores Mitogênicos/genética , Transdução de Sinais
10.
Am J Vet Res ; 83(6)2022 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-35524958

RESUMO

OBJECTIVE: To quantify dectin-1 expression in bronchoalveolar lavage fluid (BALF), create polyclonal antibodies against equine dectin-1 and localize it in tissues, and quantify fungal exposure in pastured and stabled asthmatic and nonasthmatic horses. SAMPLES: BALF samples from 6 controls and 6 horses with severe asthma. Stored lung and nasal wash samples. PROCEDURES: Dectin-1 expression was quantified by quantitative PCR (qPCR). Purified peptide from equine dectin-1 was used to generate polyclonal antibodies and was confirmed with immunological testing. Fungal exposure was quantified in BALF samples by counting fungal-like intracellular particles in phagocytic cells, by qPCR quantification of the "universal" 18S rRNA fungal gene, and by quantifying 36 specific fungi in equine and dust samples using qPCR assays. RESULTS: Equine dectin-1 was localized in tissues and cells, and functional isoforms were upregulated significantly in BALF after stabling. Pastured horses from both groups had low levels of fungi in BALF, and there was a significant increase in some specific fungi, most notably for Eurotium amstelodami, Wallemia sebi, and Aspergillus niger after stabling. However, stabled asthmatic horses had fewer phagocytized particles, less 18S rRNA signal, and fewer specific fungi compared to nonasthmatic horses. CLINICAL RELEVANCE: Stabling increases exposure to fungi, but asthmatic horses had fewer fungi reaching their lower airways, presumably resulting from congestion and narrowing of the airways. Exposure to fungi could contribute to airway inflammation by increasing dectin-1 functional isoforms, and exposure to indoor molds should be avoided.


Assuntos
Asma , Doenças dos Cavalos , Animais , Asma/veterinária , Líquido da Lavagem Broncoalveolar , Cavalos , Lectinas Tipo C , RNA Ribossômico 18S
11.
J Immunol ; 208(10): 2343-2362, 2022 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-35508356

RESUMO

The C-type lectin family with the signature C-type lectin-like domain promotes antibacterial host defense within the animal kingdom. We examined the role of Chinese mitten crab, Eriocheir sinensis (H. Milne-Edwards) (Decapoda: Grapsidae) Ig domain-containing C-type lectin (EsIgLectin), a novel and poorly understood member of the C-type lectin family. EsIgLectin was expressed primarily by both hemocytes (E sinensis) and intestines, with significantly induced mRNA expression on intestinal or hemolymph bacterial infections. As a soluble protein, both its C-type lectin-like domain and the Ig domain were required for bacterial binding, bacterial agglutination, bacterial growth inhibition, and in vivo bacterial clearance. Polymeric EsIgLectin could be constructed via the disulfide bond in the Ig domain, significantly enhancing EsIgLectin antibacterial activity. EsIgLectin promoted bacterial phagocytosis in an Ig domain-dependent manner in hemocytes, while it controlled microbial homeostasis and protected against bacteria-induced inflammation in the intestine. Protein interaction studies revealed that the EsIgLectin Ig domain bound to the first Ig domain of the polymeric Ig receptor, which was essential for EsIgLectin-induced bacterial phagocytosis. The temporal sequence of cell interactions during intestinal inflammation is only beginning to be understood. In this article, we show that hemocyte-derived EsIgLectin entered the intestinal wall at the later phase of intestinal inflammation. Moreover, EsIgLectin protected the host against intestinal and hemolymph infections in a polymeric Ig receptor-dependent manner. Therefore, the EsIgLectin promoted bacterial clearance and protected against inflammatory disease through an independent or synergistic effect of hemocytes and intestines in invertebrates.


Assuntos
Hemócitos , Receptores de Imunoglobulina Polimérica , Animais , Antibacterianos , Proteínas de Artrópodes/genética , Bactérias , Imunidade Inata , Domínios de Imunoglobulina , Inflamação , Intestinos , Lectinas Tipo C , Filogenia
12.
Front Immunol ; 13: 894445, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35619716

RESUMO

As a subset of pattern recognition receptors (PRRs), C-type lectin-like receptors (CLRs) are mainly expressed by myeloid cells as both transmembrane and soluble forms. CLRs recognize not only pathogen associated molecular patterns (PAMPs), but also damage-associated molecular patterns (DAMPs) to promote innate immune responses and affect adaptive immune responses. Upon engagement by PAMPs or DAMPs, CLR signaling initiates various biological activities in vivo, such as cytokine secretion and immune cell recruitment. Recently, several CLRs have been implicated as contributory to the pathogenesis of intestinal inflammation, which represents a prominent risk factor for colorectal cancer (CRC). CLRs function as an interface among microbiota, intestinal epithelial barrier and immune system, so we firstly discussed the relationship between dysbiosis caused by microbiota alteration and inflammatory bowel disease (IBD), then focused on the role of CLRs signaling in pathogenesis of IBD (including Mincle, Dectin-3, Dectin-1, DCIR, DC-SIGN, LOX-1 and their downstream CARD9). Given that CLRs mediate intricate inflammatory signals and inflammation plays a significant role in tumorigenesis, we finally highlight the specific effects of CLRs on CRC, especially colitis-associated cancer (CAC), hoping to open new horizons on pathogenesis and therapeutics of IBD and CAC.


Assuntos
Microbioma Gastrointestinal , Doenças Inflamatórias Intestinais , Neoplasias Intestinais , Microbiota , Humanos , Inflamação , Lectinas Tipo C , Padrões Moleculares Associados a Patógenos
13.
Clin Drug Investig ; 42(5): 447-458, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35501592

RESUMO

BACKGROUND AND OBJECTIVE: The search for potential gene loci that affect the pharmacodynamics and pharmacokinetics of ticagrelor is a matter of broad clinical interest. The objective of this study was to investigate the effect of genetic polymorphisms on the pharmacokinetics and pharmacodynamics of ticagrelor in healthy Chinese subjects. METHODS: This is a multi-center study in China, including three hospitals from Beijing, Nanchang, and Changsha. Healthy Chinese subjects aged 18-45 years with unknown genotypes were included. All subjects received a single oral dose of 90 mg of ticagrelor. Platelet aggregation and the area under the concentration-time curve for ticagrelor and its major active metabolite in plasma samples were assessed. Genome-wide association studies and candidate gene association analysis related to ticagrelor were performed. RESULTS: One hundred and seventy-five native Chinese subjects were enrolled and completed the study. According to the p value, the threshold of ticagrelor population was 6.57 × 10-7 (0.05/76106), one single-nucleotide polymorphism chr6:17616513 of gene NUP153 (p = 2.03 × 10-7) related to the area under the concentration-time curve for plasma concentration at time zero versus the last measurable timepoint, and one single nucleotide polymorphism rs17204533 of gene SVEP1 (p = 3.96 × 10-7) related to P2Y12 reaction unit12h of ticagrelor was identified. In addition, L1TD1, CETP, CLEC2A, CHSY1, PDZRN3, CTU2, PIEZO1, APOBEC1, SEMA6A, KAZN, and FASN polymorphisms might influence the pharmacokinetics of ticagrelor, while PARP10, TRIB1, CYP2C19, and UGT2B7 might affected its pharmacodynamics. CONCLUSIONS: Genetic variation affects the pharmacokinetics and pharmacodynamics of ticagrelor in healthy individuals. The detection of NUP153, SVEP1 gene variation will be helpful for pharmacodynamic prediction and evaluation, and the regulation of these genes may be the target of new drug development. Further studies are required to confirm the results and explore whether these single-nucleotide polymorphisms are associated only with platelet activity or also with cardiovascular events and all-cause mortality. CLINICAL TRIAL REGISTRATION: NCT03161002.


Assuntos
Estudo de Associação Genômica Ampla , Antagonistas do Receptor Purinérgico P2Y , Adenosina , Moléculas de Adesão Celular , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/farmacologia , Canais Iônicos , Lectinas Tipo C , Complexo de Proteínas Formadoras de Poros Nucleares/farmacologia , Nucleotídeos/farmacologia , Agregação Plaquetária , Inibidores da Agregação Plaquetária , Poli(ADP-Ribose) Polimerases/farmacologia , Polimorfismo de Nucleotídeo Único/genética , Proteínas Proto-Oncogênicas , Ticagrelor
14.
Front Immunol ; 13: 898198, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35634312

RESUMO

Aedes aegypti is one of the world's most dangerous mosquitoes, and a vector of diseases such as dengue fever, chikungunya virus, yellow fever, and Zika virus disease. Currently, a major global challenge is the scarcity of antiviral medicine and vaccine for arboviruses. Bacillus thuringiensis var israelensis (Bti) toxins are used as biological mosquito control agents. Endotoxins, including Cry4Aa, Cry4Ba, Cry10Aa, Cry11Aa, and Cyt1Aa, are toxic to mosquitoes. Insect eradication by Cry toxin relies primarily on the interaction of cry toxins with key toxin receptors, such as aminopeptidase (APN), alkaline phosphatase (ALP), cadherin (CAD), and ATP-binding cassette transporters. The carbohydrate recognition domains (CRDs) of lectins and domains II and III of Cry toxins share similar structural folds, suggesting that midgut proteins, such as C-type lectins (CTLs), may interfere with interactions among Cry toxins and receptors by binding to both and alter Cry toxicity. In the present review, we summarize the functional role of C-type lectins in Ae. aegypti mosquitoes and the mechanism underlying the alteration of Cry toxin activity by CTLs. Furthermore, we outline future research directions on elucidating the Bti resistance mechanism. This study provides a basis for understanding Bti resistance, which can be used to develop novel insecticides.


Assuntos
Aedes , Infecção por Zika virus , Zika virus , Aedes/metabolismo , Animais , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/metabolismo , Lectinas Tipo C/metabolismo , Mosquitos Vetores , Zika virus/metabolismo
15.
Sci Rep ; 12(1): 7282, 2022 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-35508614

RESUMO

As photoreceptor cells die during retinal degeneration, the surrounding microenvironment undergoes significant changes that are increasingly recognized to play a prominent role in determining the efficacy of therapeutic interventions. Chondroitin Sulphate Proteoglycans (CSPGs) are a major component of the extracellular matrix that have been shown to inhibit neuronal regrowth and regeneration in the brain and spinal cord, but comparatively little is known about their expression in retinal degeneration. Here we provide a comprehensive atlas of the expression patterns of four individual CSPGs in three models of inherited retinal degeneration and wildtype mice. In wildtype mice, Aggrecan presented a biphasic expression, while Neurocan and Phosphacan expression declined dramatically with time and Versican expression remained broadly constant. In degeneration, Aggrecan expression increased markedly in Aipl1-/- and Pde6brd1/rd1, while Versican showed regional increases in the periphery of Rho-/- mice. Conversely, Neurocan and Phosphacan broadly decrease with time in all models. Our data reveal significant heterogeneity in the expression of individual CSPGs. Moreover, there are striking differences in the expression patterns of specific CSPGs in the diseased retina, compared with those reported following injury elsewhere in the CNS. Better understanding of the distinct distributions of individual CSPGs will contribute to creating more permissive microenvironments for neuro-regeneration and repair.


Assuntos
Neurocam , Degeneração Retiniana , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Agrecanas/genética , Agrecanas/metabolismo , Animais , Proteoglicanas de Sulfatos de Condroitina/genética , Proteoglicanas de Sulfatos de Condroitina/metabolismo , Lectinas Tipo C/metabolismo , Camundongos , Proteínas do Tecido Nervoso/metabolismo , Neurocam/metabolismo , Proteínas Tirosina Fosfatases Classe 5 Semelhantes a Receptores/metabolismo , Retina/metabolismo , Degeneração Retiniana/genética , Versicanas/genética , Versicanas/metabolismo
16.
Eur J Pharmacol ; 926: 175032, 2022 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-35584710

RESUMO

Recent evidence suggests that Nod-like receptor protein-3 (NLRP3) inflammasome is a key mediator of inflammatory response and can induce the activation of apoptosis signaling pathways in ischemic stroke. In this research, we assessed the effects of anfibatide (ANF) on inflammatory and apoptosis in cerebral ischemic injury and the potential mechanisms. Middle cerebral artery occlusion (MCAO) model was established on male Sprague-Dawley rats to induce cerebral ischemia/reperfusion (I/R) injury in vivo. Primary cortical neurons (PCN) cells were exposed to oxygen-glucose deprivation and reintroduction (OGD/R) to mimic cerebral I/R injury in vitro. The results showed that ANF markedly alleviated infarct volume, neurological deficit and neurobehavioral impairment in MCAO/R rats, enhanced cell viability and decreased LDH release in PCN after OGD/R. The number of TUNEL-positive cells, Bax, cleaved-caspase-3, p-IκBα, p-p65, NLRP3, ASC, cleaved caspase-1, IL-ß and IL-18 proteins expression were significantly upregulated in the cortex of MCAO/R rats and PCN exposed to OGD/R, NLRP3 and caspase-1 mRNA levels were also evidently elevated. Bcl-2 protein expression significantly decreased in the cortex of MCAO/R rats. Treatment with ANF obviously inhibited the expression of p-IκBα, p-p65, NLRP3, ASC, cleaved caspase-1, Bax and cleaved-caspase-3, promoted the expression of Bcl-2, then decreased the TUNEL-positive cell number and the level of inflammatory cytokines (IL-ß and IL-18) in cerebral ischemia reperfusion in vito and in vitro. Our findings suggest that ANF exerts effects of alleviating inflammation and apoptosis through inhibiting NF-kappaB/NLRP3 axis. ANF is a potential candidate for treating cerebral I/R injury.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Traumatismo por Reperfusão , Animais , Apoptose , Fator Natriurético Atrial/farmacologia , Isquemia Encefálica/complicações , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Caspase 3 , Venenos de Crotalídeos , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/metabolismo , Inflamação/tratamento farmacológico , Interleucina-18 , Lectinas Tipo C , Masculino , Inibidor de NF-kappaB alfa , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteínas NLR , Carbonitrila de Pregnenolona/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2 , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/complicações , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo , Proteína X Associada a bcl-2
17.
J Proteomics ; 263: 104613, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35589061

RESUMO

Lataste's viper (Vipera latastei) is a venomous European viper endemic to the Iberian Peninsula, recognised as medically important by the World Health Organization. To date, no comprehensive characterisation of this species' venom has been reported. Here, we analysed the venoms of juvenile and adult specimens of V. latastei from two environmentally different populations from northern Portugal. Using bottom-up venomics, we produced six venom proteomes (three per population) from vipers belonging to both age classes (i.e., two juveniles and four adults), and RP-HPLC profiles of 54 venoms collected from wild specimens. Venoms from juveniles and adults differed in their chromatographic profiles and relative abundances of their toxins, suggesting the occurrence of ontogenetic changes in venom composition. Specifically, snake venom metalloproteinase (SVMP) was the most abundant toxin family in juvenile venoms, while snake venom serine proteinases (SVSPs), phospholipases A2 (PLA2s), and C-type lectin-like (CTLs) proteins were the main toxins comprising adult venoms. The RP-HPLC venom profiles were found to vary significantly between the two sampled localities, indicating geographic variability. Furthermore, the presence/absence of certain peaks in the venom chromatographic profiles appeared to be significantly correlated also to factors like body size and sex of the vipers. Our findings show that V. latastei venom is a variable phenotype. The intraspecific differences we detected in its composition likely mirror changes in the feeding ecology of this species, taking place during different life stages and under different environmental pressures. SIGNIFICANCE: Lataste's viper (Vipera latastei) is a medically important viper endemic to the Iberian Peninsula, inhabiting different habitats and undergoing a marked ontogenetic dietary shift. In the current study, we report the first proteomic analysis of V. latastei venom from two environmentally different localities in northern Portugal. Our bottom-up venomic analyses show that snake venom serine proteinases (SVSPs), phospholipases A2 (PLA2s), and C-type lectin-like (CTLs) proteins are the major components of adult V. latastei venom. The comparative analysis of young and adult venoms suggests the occurrence of ontogenetic shift in toxin abundances, with snake venom metalloproteinases (SVMPs) being the predominant toxins in juvenile venoms. Moreover, geographic venom variation between the two studied populations is also detected, with our statistical analyses suggesting that factors like body size and sex of the vipers are possibly at play in its determination. Our work represents the first assessment of the composition of V. latastei venom, and the first step towards a better understanding of the drivers behind its variability.


Assuntos
Toxinas Biológicas , Viperidae , Animais , Lectinas Tipo C , Metaloproteases/metabolismo , Fosfolipases A2/análise , Portugal , Proteômica/métodos , Serina Proteases , Venenos de Serpentes/química , Toxinas Biológicas/análise , Venenos de Víboras/química , Viperidae/metabolismo
18.
Carbohydr Res ; 517: 108580, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35561476

RESUMO

Food allergy induced by lipid transfer proteins (LTPs) of Rosacea fruit family, such as peach, is becoming an important health problem in the Mediterranean area. Current treatments, such as allergen specific immunotherapy (AIT) with allergenic extracts show promising, but in many cases, they need an improvement in homogeneity, availability and induction of tolerant responses. Peptide-based vaccines containing adjuvants, such as carbohydrates for C-type lectin receptors (CLRs) are presented as an alternative approach. In this work, we have prepared fucosylated glycodendropeptides (GDPs) functionalized with Pru p 3 peptides via click chemistry. These GDPs, DnFuc9Prup3, induced changes in moDC maturation and lymphocyte proliferation in food allergic patients, indicating specific recognition via DC-SIGN receptor. From these data, D4Fuc9Prup3 can be considered a promising candidate for specific immunotherapy development.


Assuntos
Antígenos de Plantas , Proteínas de Plantas , Alérgenos , Antígenos de Plantas/metabolismo , Moléculas de Adesão Celular , Células Dendríticas/metabolismo , Humanos , Lectinas Tipo C/metabolismo , Proteínas de Plantas/metabolismo , Receptores de Superfície Celular
19.
Fish Shellfish Immunol ; 125: 17-25, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35525410

RESUMO

C-type lectins (CTLs), as a member of the Ca2+-dependent carbohydrate recognition protein superfamily, play multiple roles in non-self recognition and the elimination of invading pathogens. In this study, a C-type lectin was identified and characterized from the Pacific abalone Haliotis discus hannai (designed as HdClec), and its open reading frame (ORF) encoded a polypeptide of 163 amino acids containing a typical signal peptide and only one carbohydrate-recognition domain (CRD). The deduced amino acid sequence of CRD in HdClec shared identities ranging from 22.4% to 39.8% with that of other identified CRDs of CTLs. A novel NPN motif was found in Ca2+-binding site 2 of HdClec. The mRNA transcripts of HdClec were detectable in all the examined tissues of non-stimulated abalones, with the highest expression in hepatopancreas (224.13-fold of that in gills). The expression of HdClec mRNA in hemocytes was significantly up-regulated after Vibrio harveyi challenge. Recombinant HdClec protein (rHdClec) could bind lipopolysaccharide (LPS) and peptidoglycan (PGN) in vitro in the presence of Ca2+. Coinciding with the PAMPs binding assay, rHdClec displayed broad agglutination activities towards Gram-negative bacteria V. splendidus, V. anguillarum, V. parahaemolyticus, V. harveyi, Escherichia coli, and Gram-positive bacteria Micrococcus luteus. Moreover, rHdClec could significantly elicit the chemotactic response of hemocytes in vitro. And the phagocytosis and encapsulation ability of hemocytes could be significantly enhanced by rHdClec. All these results showed that HdClec could function as pattern recognition receptors (PRRs) and further enhance the opsonization of hemocytes, which might play a crucial role in the innate immune responses of Pacific abalone.


Assuntos
Hemócitos , Lectinas Tipo C , Animais , Carboidratos , Imunidade Inata/genética , Filogenia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Reconhecimento de Padrão/genética , Receptores de Reconhecimento de Padrão/metabolismo
20.
Front Immunol ; 13: 879337, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35615362

RESUMO

The clam Ruditapes philippinarum is an important species in the marine aquaculture industry in China. However, in recent years, the aquaculture of R. philippinarum has been negatively impacted by various bacterial pathogens. In this study, the transcriptome libraries of R. philippinarum showing different levels of resistance to challenge with Vibrio anguillarum were constructed and RNA-seq was performed using the Illumina sequencing platform. Host immune factors were identified that responded to V. anguillarum infection, including C-type lectin domain, glutathione S-transferase 9, lysozyme, methyltransferase FkbM domain, heat shock 70 kDa protein, Ras-like GTP-binding protein RHO, C1q, F-box and BTB/POZ domain protein zf-C2H2. Ten genes were selected and verified by RT-qPCR, and nine of the gene expression results were consistent with those of RNA-seq. The lectin gene in the phagosome pathway was expressed at a significantly higher level after V. anguillarum infection, which might indicate the role of lectin in the immune response to V. anguillarum. Comparing the results from R. philippinarum resistant and nonresistant to V. anguillarum increases our understanding of the resistant genes and key pathways related to Vibrio challenge in this species. The results obtained here provide a reference for future immunological research focusing on the response of R. philippinarum to V. anguillarum infection.


Assuntos
Bivalves , Vibrio , Animais , Bivalves/genética , Bivalves/imunologia , Bivalves/microbiologia , Perfilação da Expressão Gênica/métodos , Lectinas Tipo C/genética , Transcriptoma , Vibrio/imunologia , Vibrio/fisiologia
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