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1.
BMC Genomics ; 24(1): 773, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38093209

RESUMO

Plasmodium falciparum is responsible for malaria-related morbidity and mortality. PfEMP1 (P. falciparum erythrocyte membrane protein 1) mediates infected erythrocytes adhesion to various surface vascular receptors, including intercellular adhesion molecule-1 (ICAM-1), associating this interaction with severe malaria in several studies. Genetic variation in host ICAM-1 plays a significant role in determining susceptibility to malaria infection via clinical phenotypes such as the ICAM-1Kilifi variant which has been reported to be associated with susceptibility in populations. Our genomic and structural analysis of single nucleotide polymorphisms (SNPs) in ICAM-1 revealed 9 unique mutations each in its distinct A-type and BC-type PfEMP1 DBLß-interacting regions. These mutations are noted in only a few field isolates and mainly in the African/African American population. The ICAM-1Kilifi variant lies in a flexible loop proximal to the DBLß-interacting region. This analysis will assist in establishing functional correlations of reported global mutations via experimental and clinical studies and in the tailored design of population-specific genetic surveillance studies. Understanding host polymorphism as an evolutionary force in diverse populations can help to predict predisposition to disease severity and will contribute towards laying the framework for designing population-specific personalized medicines for severe malaria.


Assuntos
Malária Falciparum , Malária , Humanos , Adesão Celular , Eritrócitos/metabolismo , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/química , Molécula 1 de Adesão Intercelular/metabolismo , Malária Falciparum/genética , Mutação , Plasmodium falciparum/genética , Ligação Proteica , Proteínas de Protozoários/genética
2.
Mol Biol Cell ; 32(18): 1749-1757, 2021 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-34232700

RESUMO

To carry out their physiological responsibilities, CD4+ T lymphocytes interact with various tissues of different mechanical properties. Recent studies suggest that T cells migrate upstream on surfaces expressing intracellular adhesion molecule-1 (ICAM-1) through interaction with leukocyte function-associated antigen-1 (αLß2) (LFA-1) integrins. LFA-1 likely behaves as a mechanosensor, and thus we hypothesized that substrate mechanics might affect the ability of LFA-1 to support upstream migration of T cells under flow. Here we measured motility of CD4+ T lymphocytes on polyacrylamide gels with predetermined stiffnesses containing ICAM-1, vascular cell adhesion molecule-1 (VCAM-1), or a 1:1 mixture of VCAM-1/ICAM-1. Under static conditions, we found that CD4+ T cells exhibit an increase in motility on ICAM-1, but not on VCAM-1 or VCAM-1/ICAM-1 mixed, surfaces as a function of matrix stiffness. The mechanosensitivity of T-cell motility on ICAM-1 is overcome when VLA-4 (very late antigen-4 [α4ß1]) is ligated with soluble VCAM-1. Last, we observed that CD4+ T cells migrate upstream under flow on ICAM-1-functionalized hydrogels, independent of substrate stiffness. In summary, we show that CD4+ T cells under no flow respond to matrix stiffness through LFA-1, and that the cross-talk of VLA-4 and LFA-1 can compensate for deformable substrates. Interestingly, CD4+ T lymphocytes migrated upstream on ICAM-1 regardless of the substrate stiffness, suggesting that flow can compensate for substrate stiffness.


Assuntos
Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/fisiologia , Integrinas/metabolismo , Resinas Acrílicas/química , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos , Movimento Celular , Humanos , Hidrogéis/química , Integrina alfa4beta1/química , Integrina alfa4beta1/metabolismo , Molécula 1 de Adesão Intercelular/química , Molécula 1 de Adesão Intercelular/metabolismo , Antígeno-1 Associado à Função Linfocitária/metabolismo , Mecanotransdução Celular , Molécula 1 de Adesão de Célula Vascular/química , Molécula 1 de Adesão de Célula Vascular/metabolismo
3.
Proc Natl Acad Sci U S A ; 118(19)2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33947819

RESUMO

Most rhinoviruses, which are the leading cause of the common cold, utilize intercellular adhesion molecule-1 (ICAM-1) as a receptor to infect cells. To release their genomes, rhinoviruses convert to activated particles that contain pores in the capsid, lack minor capsid protein VP4, and have an altered genome organization. The binding of rhinoviruses to ICAM-1 promotes virus activation; however, the molecular details of the process remain unknown. Here, we present the structures of virion of rhinovirus 14 and its complex with ICAM-1 determined to resolutions of 2.6 and 2.4 Å, respectively. The cryo-electron microscopy reconstruction of rhinovirus 14 virions contains the resolved density of octanucleotide segments from the RNA genome that interact with VP2 subunits. We show that the binding of ICAM-1 to rhinovirus 14 is required to prime the virus for activation and genome release at acidic pH. Formation of the rhinovirus 14-ICAM-1 complex induces conformational changes to the rhinovirus 14 capsid, including translocation of the C termini of VP4 subunits, which become poised for release through pores that open in the capsids of activated particles. VP4 subunits with altered conformation block the RNA-VP2 interactions and expose patches of positively charged residues. The conformational changes to the capsid induce the redistribution of the virus genome by altering the capsid-RNA interactions. The restructuring of the rhinovirus 14 capsid and genome prepares the virions for conversion to activated particles. The high-resolution structure of rhinovirus 14 in complex with ICAM-1 explains how the binding of uncoating receptors enables enterovirus genome release.


Assuntos
Capsídeo/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , RNA Viral/metabolismo , Rhinovirus/metabolismo , Ativação Viral/fisiologia , Desenvelopamento do Vírus/fisiologia , Sequência de Aminoácidos , Proteínas do Capsídeo/química , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Microscopia Crioeletrônica , Cristalografia por Raios X , Infecções por Enterovirus/metabolismo , Infecções por Enterovirus/virologia , Genoma Viral/genética , Células HeLa , Humanos , Molécula 1 de Adesão Intercelular/química , Molécula 1 de Adesão Intercelular/genética , Modelos Moleculares , Conformação de Ácido Nucleico , Ligação Proteica , Conformação Proteica , RNA Viral/química , RNA Viral/genética , Rhinovirus/genética , Rhinovirus/fisiologia , Homologia de Sequência de Aminoácidos , Vírion/genética , Vírion/metabolismo , Vírion/ultraestrutura
4.
Anal Biochem ; 628: 114262, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34038704

RESUMO

Cancer is the second leading cause of death worldwide and most of the cancer-related deaths result from metastasis. As expressed on the surface of various cancer cell types, intercellular adhesion molecule-1 (ICAM-1) has been shown to play a role in the attachment, invasion and migration of tumor cells. In this study, DNA aptamers were generated against ICAM-1 by cell-SELEX and protein SELEX method using ICAM-1(+) CHO-ICAM-1 cells and ICAM-1 protein, respectively. The pools obtained at the end of the 10th round of both SELEX were sequenced and the most enriched sequences were characterized for their binding behaviors and affinities to ICAM-1(+) CHO-ICAM-1 and ICAM-1(-) MIA PaCa-2 cells. Moreover, the inhibition abilities of sequences on migration and invasion were measured. The seven aptamer sequences were obtained selectively binding to CHO-ICAM-1 cells with Kd values in the ranging from 13.8 to 47.1 nM. Four of these aptamers showed inhibition in both migration and invasion of CHO-ICAM-1 cells at least 61%. All these results suggested that these aptamers have potential to detect specifically ICAM-1 expressing tumor cells and inhibit migration and invasion by blocking ICAM-1 related interactions of circulating tumor cells.


Assuntos
Aptâmeros de Nucleotídeos/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , Técnica de Seleção de Aptâmeros , Animais , Aptâmeros de Nucleotídeos/química , Sítios de Ligação , Movimento Celular , Células Cultivadas , Cricetulus , Citometria de Fluxo , Humanos , Molécula 1 de Adesão Intercelular/química
5.
Front Immunol ; 12: 626308, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33854501

RESUMO

We have previously shown that conformational change in the ß2-integrin is a very early activation marker that can be detected with fluorescent multimers of its ligand intercellular adhesion molecule (ICAM)-1 for rapid assessment of antigen-specific CD8+ T cells. In this study, we describe a modified protocol of this assay for sensitive detection of functional antigen-specific CD4+ T cells using a monoclonal antibody (clone m24 Ab) specific for the open, high-affinity conformation of the ß2-integrin. The kinetics of ß2-integrin activation was different on CD4+ and CD8+ T cells (several hours vs. few minutes, respectively); however, m24 Ab readily stained both cell types 4-6 h after antigen stimulation. With this protocol, we were able to monitor ex vivo effector and memory CD4+ and CD8+ T cells specific for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), cytomegalovirus (CMV), Epstein-Barr virus (EBV), and hepatitis B virus (HBV) in whole blood or cryopreserved peripheral blood mononuclear cells (PBMCs) of infected or vaccinated individuals. By costaining ß2-integrin with m24 and CD154 Abs, we assessed extremely low frequencies of polyfunctional CD4+ T cell responses. The novel assay used in this study allows very sensitive and simultaneous screening of both CD4+ and CD8+ T cell reactivities, with versatile applicability in clinical and vaccination studies.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Interações Hospedeiro-Patógeno/imunologia , Integrinas/metabolismo , Adulto , Idoso , Sequência de Aminoácidos , Sítios de Ligação , COVID-19/genética , COVID-19/imunologia , COVID-19/metabolismo , COVID-19/virologia , Proteínas de Transporte/química , Citocinas/metabolismo , Citomegalovirus/imunologia , Epitopos de Linfócito T/química , Epitopos de Linfócito T/imunologia , Feminino , Antígenos HLA/química , Antígenos HLA/imunologia , Interações Hospedeiro-Patógeno/genética , Humanos , Imuno-Histoquímica , Imunofenotipagem , Integrinas/genética , Molécula 1 de Adesão Intercelular/química , Molécula 1 de Adesão Intercelular/metabolismo , Ativação Linfocitária/imunologia , Masculino , Pessoa de Meia-Idade , Ligação Proteica , Multimerização Proteica , SARS-CoV-2/imunologia , Especificidade do Receptor de Antígeno de Linfócitos T , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo
6.
J Proteomics ; 234: 104083, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33373718

RESUMO

Using high-throughput BioPlex assays, we determined that six fractions from the venom of Conus nux inhibit the adhesion of various recombinant PfEMP-1 protein domains (PF08_0106 CIDR1α3.1, PF11_0521 DBL2ß3, and PFL0030c DBL3X and DBL5e) to their corresponding receptors (CD36, ICAM-1, and CSA, respectively). The protein domain-receptor interactions permit P. falciparum-infected erythrocytes (IE) to evade elimination in the spleen by adhering to the microvasculature in various organs including the placenta. The sequences for the main components of the fractions, determined by tandem mass spectrometry, yielded four T-superfamily conotoxins, one (CC-Loop-CC) with I-IV, II-III connectivity and three (CC-Loop-CXaaC) with a I-III, II-IV connectivity. The 3D structure for one of the latter, NuxVA = GCCPAPLTCHCVIY, revealed a novel scaffold defined by double turns forming a hairpin-like structure stabilized by the two disulfide bonds. Two other main fraction components were a miniM conotoxin, and a O2-superfamily conotoxin with cysteine framework VI/VII. This study is the first one of its kind suggesting the use of conotoxins for developing pharmacological tools for anti-adhesion adjunct therapy against malaria. Similarly, mitigation of emerging diseases like AIDS and COVID-19, can also benefit from conotoxins as inhibitors of protein-protein interactions as treatment. BIOLOGICAL SIGNIFICANCE: Among the 850+ species of cone snail species there are hundreds of thousands of diverse venom exopeptides that have been selected throughout several million years of evolution to capture prey and deter predators. They do so by targeting several surface proteins present in target excitable cells. This immense biomolecular library of conopeptides can be explored for potential use as therapeutic leads against persistent and emerging diseases affecting non-excitable systems. We aim to expand the pharmacological reach of conotoxins/conopeptides by revealing their in vitro capacity to disrupt protein-protein and protein-polysaccharide interactions that directly contribute to pathology of Plasmodium falciparum malaria. This is significant for severe forms of malaria, which might be deadly even after treated with current parasite-killing drugs because of persistent cytoadhesion of P. falciparum infected erythrocytes even when parasites within red blood cells are dead. Anti-adhesion adjunct drugs would de-sequester or prevent additional sequestration of infected erythrocytes and may significantly improve survival of malaria patients. These results provide a lead for further investigations into conotoxins and other venom peptides as potential candidates for anti-adhesion or blockade-therapies. This study is the first of its kind and it suggests that conotoxins can be developed as pharmacological tools for anti-adhesion adjunct therapy against malaria. Similarly, mitigation of emerging diseases like AIDS and COVID-19, can also benefit from conotoxins as potential inhibitors of protein-protein interactions as treatment.


Assuntos
Antígenos CD36 , Enzimas Reparadoras do DNA , Eritrócitos , Molécula 1 de Adesão Intercelular , Venenos de Moluscos , Plasmodium falciparum , Fatores de Transcrição , Animais , Antígenos CD36/química , Antígenos CD36/metabolismo , COVID-19 , Caramujo Conus , Enzimas Reparadoras do DNA/química , Enzimas Reparadoras do DNA/metabolismo , Eritrócitos/química , Eritrócitos/metabolismo , Eritrócitos/parasitologia , Humanos , Molécula 1 de Adesão Intercelular/química , Molécula 1 de Adesão Intercelular/metabolismo , Venenos de Moluscos/química , Venenos de Moluscos/farmacologia , Plasmodium falciparum/química , Plasmodium falciparum/metabolismo , Domínios Proteicos , Proteínas de Protozoários , SARS-CoV-2 , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo
7.
Molecules ; 26(1)2020 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-33374825

RESUMO

By using various chromatographic steps (silica flash, CPC, preparative HPLC), 16 sesquiterpenes could be isolated from an ethanolic extract of myrrh resin. Their chemical structures were elucidated by 1D and 2D NMR spectroscopy and HRESIMS. Among them, six previously unknown compounds (1-6) and another four metabolites previously not described for the genus Commiphora (7, 10, 12, 13) could be identified. Sesquiterpenes 1 and 2 are novel 9,10-seco-eudesmanes and exhibited an unprecedented sesquiterpene carbon skeleton, which is described here for the first time. New compound 3 is an 9,10 seco-guaian and the only peroxide isolated from myrrh so far. Compounds 1, 2, 4, 7-9, 11, 13-16 were tested in an ICAM-1 in vitro assay. Compound 7, as well as the reference compound furanoeudesma-1,3-diene, acted as moderate inhibitors of this adhesion molecule ICAM-1 (IC50: 44.8 and 46.3 µM, respectively). These results give new hints on the activity of sesquiterpenes with regard to ICAM-1 inhibition and possible modes of action of myrrh in anti-inflammatory processes.


Assuntos
Commiphora/química , Molécula 1 de Adesão Intercelular/química , Extratos Vegetais/farmacologia , Sesquiterpenos/farmacologia , Humanos , Técnicas In Vitro , Molécula 1 de Adesão Intercelular/metabolismo , Estrutura Molecular
8.
Proc Natl Acad Sci U S A ; 117(41): 25254-25262, 2020 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-32989130

RESUMO

Multisystem Inflammatory Syndrome in Children (MIS-C) associated with COVID-19 is a newly recognized condition in children with recent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. These children and adult patients with severe hyperinflammation present with a constellation of symptoms that strongly resemble toxic shock syndrome, an escalation of the cytotoxic adaptive immune response triggered upon the binding of pathogenic superantigens to T cell receptors (TCRs) and/or major histocompatibility complex class II (MHCII) molecules. Here, using structure-based computational models, we demonstrate that the SARS-CoV-2 spike (S) glycoprotein exhibits a high-affinity motif for binding TCRs, and may form a ternary complex with MHCII. The binding epitope on S harbors a sequence motif unique to SARS-CoV-2 (not present in other SARS-related coronaviruses), which is highly similar in both sequence and structure to the bacterial superantigen staphylococcal enterotoxin B. This interaction between the virus and human T cells could be strengthened by a rare mutation (D839Y/N/E) from a European strain of SARS-CoV-2. Furthermore, the interfacial region includes selected residues from an intercellular adhesion molecule (ICAM)-like motif shared between the SARS viruses from the 2003 and 2019 pandemics. A neurotoxin-like sequence motif on the receptor-binding domain also exhibits a high tendency to bind TCRs. Analysis of the TCR repertoire in adult COVID-19 patients demonstrates that those with severe hyperinflammatory disease exhibit TCR skewing consistent with superantigen activation. These data suggest that SARS-CoV-2 S may act as a superantigen to trigger the development of MIS-C as well as cytokine storm in adult COVID-19 patients, with important implications for the development of therapeutic approaches.


Assuntos
Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Pneumonia Viral/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo , Superantígenos/metabolismo , Síndrome de Resposta Inflamatória Sistêmica/imunologia , Motivos de Aminoácidos , Betacoronavirus/química , Betacoronavirus/genética , Betacoronavirus/metabolismo , COVID-19 , Infecções por Coronavirus/genética , Infecções por Coronavirus/patologia , Enterotoxinas/química , Epitopos de Linfócito T , Humanos , Molécula 1 de Adesão Intercelular/química , Modelos Moleculares , Mutação , Neurotoxinas/química , Pandemias , Pneumonia Viral/genética , Pneumonia Viral/patologia , Ligação Proteica , Receptores de Antígenos de Linfócitos T/química , Receptores de Antígenos de Linfócitos T/genética , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Superantígenos/química , Superantígenos/genética , Síndrome de Resposta Inflamatória Sistêmica/genética , Síndrome de Resposta Inflamatória Sistêmica/patologia
9.
J Leukoc Biol ; 108(3): 787-799, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32182390

RESUMO

ICAM-1 is a cell surface glycoprotein and an adhesion receptor that is best known for regulating leukocyte recruitment from circulation to sites of inflammation. However, in addition to vascular endothelial cells, ICAM-1 expression is also robustly induced on epithelial and immune cells in response to inflammatory stimulation. Importantly, ICAM-1 serves as a biosensor to transduce outside-in-signaling via association of its cytoplasmic domain with the actin cytoskeleton following ligand engagement of the extracellular domain. Thus, ICAM-1 has emerged as a master regulator of many essential cellular functions both at the onset and at the resolution of pathologic conditions. Because the role of ICAM-1 in driving inflammatory responses is well recognized, this review will mainly focus on newly emerging roles of ICAM-1 in epithelial injury-resolution responses, as well as immune cell effector function in inflammation and tumorigenesis. ICAM-1 has been of clinical and therapeutic interest for some time now; however, several attempts at inhibiting its function to improve injury resolution have failed. Perhaps, better understanding of its beneficial roles in resolution of inflammation or its emerging function in tumorigenesis will spark new interest in revisiting the clinical value of ICAM-1 as a potential therapeutic target.


Assuntos
Carcinogênese , Inflamação/fisiopatologia , Molécula 1 de Adesão Intercelular/fisiologia , Cicatrização/fisiologia , Processamento Alternativo , Animais , Biomarcadores , Quimiotaxia de Leucócito/fisiologia , Endotélio Vascular/fisiologia , Epitélio/fisiologia , Humanos , Inflamação/sangue , Molécula 1 de Adesão Intercelular/sangue , Molécula 1 de Adesão Intercelular/química , Camundongos , Metástase Neoplásica , Células-Tronco Neoplásicas/citologia , Fosforilação , Prognóstico , Processamento de Proteína Pós-Traducional , Nicho de Células-Tronco
10.
Proc Natl Acad Sci U S A ; 116(40): 20124-20134, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31527263

RESUMO

A major determinant of pathogenicity in malaria caused by Plasmodium falciparum is the adhesion of parasite-infected erythrocytes to the vasculature or tissues of infected individuals. This occludes blood flow, leads to inflammation, and increases parasitemia by reducing spleen-mediated clearance of the parasite. This adhesion is mediated by PfEMP1, a multivariant family of around 60 proteins per parasite genome which interact with specific host receptors. One of the most common of these receptors is intracellular adhesion molecule-1 (ICAM-1), which is bound by 2 distinct groups of PfEMP1, A-type and B or C (BC)-type. Here, we present the structure of a domain from a B-type PfEMP1 bound to ICAM-1, revealing a complex binding site. Comparison with the existing structure of an A-type PfEMP1 bound to ICAM-1 shows that the 2 complexes share a globally similar architecture. However, while the A-type PfEMP1 bind ICAM-1 through a highly conserved binding surface, the BC-type PfEMP1 use a binding site that is more diverse in sequence, similar to how PfEMP1 interact with other human receptors. We also show that A- and BC-type PfEMP1 present ICAM-1 at different angles, perhaps influencing the ability of neighboring PfEMP1 domains to bind additional receptors. This illustrates the deep diversity of the PfEMP1 and demonstrates how variations in a single domain architecture can modulate binding to a specific ligand to control function and facilitate immune evasion.


Assuntos
Eritrócitos/metabolismo , Eritrócitos/parasitologia , Molécula 1 de Adesão Intercelular/química , Molécula 1 de Adesão Intercelular/metabolismo , Malária Falciparum/parasitologia , Plasmodium falciparum/fisiologia , Motivos de Aminoácidos , Sequência de Aminoácidos , Sítios de Ligação , Adesão Celular , Humanos , Malária Falciparum/metabolismo , Modelos Moleculares , Ligação Proteica , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas , Proteínas de Protozoários/química , Proteínas de Protozoários/metabolismo , Relação Estrutura-Atividade
11.
Cytometry A ; 95(8): 843-853, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31294926

RESUMO

A rapid, high-throughput, and quantitative method for cell entry route characterization is still lacking in nanomedicine research. Here, we report the application of imaging flow cytometry for quantitatively analyzing cell entry routes of actively targeted nanomedicines. We first engineered ICAM1 antibody-directed fusogenic nanoliposomes (ICAM1-FusoNLPs) and ICAM1 antibody-directed endocytic nanolipogels (ICAM1-EndoNLGs) featuring highly similar surface properties but different cell entry routes: receptor-mediated membrane fusion and receptor-mediated endocytosis, respectively. By using imaging flow cytometry, we characterized their intracellular delivery into human breast cancer MDA-MB-231 cells. We found that ICAM1-FusoNLPs mediated a 2.8-fold increased cell uptake of fluorescent payload, FITC-dextran, with a 2.4-fold increased intracellular distribution area in comparison with ICAM1-EndoNLGs. We also investigated the effects of incubation time and endocytic inhibitors on the cell entry routes of ICAM1-FusoNLP and ICAM1-EndoNLG. Our results indicate that receptor-mediated membrane fusion is a faster and more efficient cell entry route than receptor-mediated endocytosis, bringing with it a significant therapeutic benefit in a proof-of-principle nanomedicine-mediated siRNA transfection experiment. Our studies suggest that cell entry route may be an important design parameter to be considered in the development of next-generation nanomedicines. © 2019 International Society for Advancement of Cytometry.


Assuntos
Endocitose/genética , Citometria de Fluxo , Molécula 1 de Adesão Intercelular/ultraestrutura , Lipossomos/química , Anticorpos/química , Linhagem Celular Tumoral , Humanos , Molécula 1 de Adesão Intercelular/química , Molécula 1 de Adesão Intercelular/genética , Lipossomos/ultraestrutura , Nanomedicina , RNA Interferente Pequeno/química , RNA Interferente Pequeno/ultraestrutura , Internalização do Vírus
12.
Int J Radiat Oncol Biol Phys ; 103(3): 697-708, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30342090

RESUMO

PURPOSE: This study examined tumor growth delay resulting from partial irradiation in preclinical mouse models. METHODS AND MATERIALS: We investigated 67NR murine orthotopic breast tumors in both immunocompetent and nude mice. Treatment was delivered to 50% or 100% of the tumor using a 2 × 2 cm collimator on a microirradiator. Radiation response was modulated by treatment with anti-CD8 and anti-intercellular adhesion molecule (anti-ICAM) antibodies. Similar experiments were performed using the less immunogenic Lewis lung carcinoma mouse model. Tumor growth delay and γ-H2AX phosphorylation were measured, and immune response was assessed by immunofluorescence and flow cytometry at 1 and 7 days after radiation therapy. Tumor expression of cellular adhesion molecules was also measured at different times after radiation therapy. RESULTS: Partial irradiation led to tumor responses similar to those of fully exposed tumors in immunocompetent mice, but not in nude mice. After a single dose of 10 Gy, infiltration of CD8+ T cells was observed along with increased expression of ICAM. The response to 10 Gy in hemi-irradiated tumors was abrogated by treatment with either anti-CD8 or anti-ICAM antibodies. Similar responses were obtained in the less immunogenic Lewis lung carcinoma mouse model delivering 15 Gy to half the tumor volume. Treatment with FTY720, a compound that inhibits T-cell egress from lymph nodes, did not affect tumor response at the time of CD8+ T cells infiltration in the nonirradiated area of the tumor. This result indicated that the most likely source of these cells is the irradiated portion of the hemi-irradiated tumors. In addition, a significant abscopal effect was observed after partial irradiation with a single dose of 10 Gy in the 67NR model. CONCLUSIONS: In these models, radiation controls tumor growth both directly through cell killing and indirectly through immune activation. This outcome raises the possibility that this effect could be induced in the clinic.


Assuntos
Antineoplásicos/uso terapêutico , Sistema Imunitário/efeitos da radiação , Transplante de Neoplasias , Radioterapia/métodos , Animais , Linfócitos T CD8-Positivos/citologia , Carcinoma Pulmonar de Lewis , Linhagem Celular Tumoral , Dano ao DNA , Modelos Animais de Doenças , Molécula 1 de Adesão Intercelular/química , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Nus , Microscopia de Fluorescência , Neoplasias/radioterapia , Dosagem Radioterapêutica , Linfócitos T/efeitos da radiação
13.
Nanomedicine ; 15(1): 25-36, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30193816

RESUMO

Effective treatment for acute lung injury (ALI) is in high demand. Lung-targeted ternary nanoparticles containing anti-intercellular adhesion molecule-1 (ICAM-1) antibody-conjugated simvastatin-loaded nanostructured lipid carrier (ICAM/NLC), protamine (Pro), and angiopoietin-1 (Ang-1) gene (ICAM-NLC/Pro/Ang) were developed for ALI therapy. The ternary nanoparticles with different weight ratios of ICAM-NLC to Ang-1 gene were prepared via charge interaction. The anti-ICAM-1 antibody-conjugated ternary nanoparticles exhibited higher cellular uptake and transfection efficiency (from 26.7% to 30.9%) in human vascular endothelial cell line EAhy926 than the non-targeted control. The largest size of ICAM-NLC/Pro/Ang (357.1 nm) was employed for further study, which significantly up-regulated in vitro and in vivo Ang-1 protein expression. In vivo i.v. administration of ICAM-NLC/Pro/Ang (357.1 nm) significantly attenuated pulmonary TNF-α and IL-6 levels, inflammatory cell infiltration, and led to positive histological improvements in lipopolysaccharide-induced ALI mice. Collectively, the ICAM-NLC/Pro/Ang that co-delivered simvastatin and Ang-1 gene may represent a potential treatment modality for ALI.


Assuntos
Lesão Pulmonar Aguda/terapia , Angiopoietina-1/administração & dosagem , Anticorpos/administração & dosagem , Sistemas de Liberação de Medicamentos , Molécula 1 de Adesão Intercelular/administração & dosagem , Nanopartículas/administração & dosagem , Sinvastatina/administração & dosagem , Células A549 , Lesão Pulmonar Aguda/genética , Lesão Pulmonar Aguda/patologia , Angiopoietina-1/química , Angiopoietina-1/genética , Animais , Anticorpos/química , Anticolesterolemiantes/administração & dosagem , Anticolesterolemiantes/química , Células Cultivadas , Terapia Combinada , Portadores de Fármacos , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Terapia Genética , Humanos , Molécula 1 de Adesão Intercelular/química , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/química , Sinvastatina/química
14.
J Colloid Interface Sci ; 538: 630-637, 2019 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-30554096

RESUMO

The development of effective targeted therapies for triple negative breast cancer (TNBC) remains a challenge. This targeted drug delivery system used a near-infrared fluorescence dye cyanine 5.5 (Cy5.5) and an ICAM-1 antibody on thioether-bridged periodic mesoporous organosilica nanoparticles (PMOs). The ICAM-1 antibody and cyanine 5.5-engineered PMOs (PMO-Cy5.5-ICAM) offer excellent in vivo and in vitro biocompatibility. The PMO-Cy5.5-ICAM shows a loading capacity up to 400 mg/g of doxorubicin (DOX). The drug release profile of the DOX-loaded targeted delivery system (DOX@PMO-Cy5.5-ICAM) is pH-sensitive. Confocal microscopy showed that the PMO-Cy5.5-ICAM efficiently targets and enters TNBC cells. In in vivo experiments, the DOX@PMO-Cy5.5-ICAM accumulates more in TNBCs than in the control groups and exhibits better therapeutic effects on TNBC; thus, it is a promising treatment strategy for TNBC.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Anticorpos/química , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Molécula 1 de Adesão Intercelular/química , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Animais , Antibióticos Antineoplásicos/química , Carbocianinas/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Doxorrubicina/química , Portadores de Fármacos/química , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/química , Compostos de Organossilício/química , Tamanho da Partícula , Porosidade , Relação Estrutura-Atividade , Propriedades de Superfície , Neoplasias de Mama Triplo Negativas/patologia
15.
Front Immunol ; 9: 952, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29774029

RESUMO

Maintenance of homeostatic immune surveillance and development of effective adaptive immune responses require precise regulation of spatial and temporal lymphocyte trafficking throughout the body to ensure pathogen clearance and memory generation. Dysregulation of lymphocyte activation and migration can lead to impaired adaptive immunity, recurrent infections, and an array of autoimmune diseases and chronic inflammation. Central to the recruitment of T cells, integrins are cell surface receptors that regulate adhesion, signal transduction, and migration. With 24 integrin pairs having been discovered to date, integrins are defined not only by the composition of the heterodimeric pair but by cell-type specific expression and their ligands. Furthermore, integrins not only facilitate adhesion but also induce intracellular signaling and have recently been uncovered as mechanosensors providing additional complexity to the signaling pathways. Among several leukocyte-specific integrins, lymphocyte function-associated antigen-1 (LFA-1 or αLß2; CD11a/CD18) is a key T cell integrin, which plays a major role in regulating T cell activation and migration. Adhesion to LFA-1's ligand, intracellular adhesion receptor 1 (ICAM-1) facilitates firm endothelium adhesion, prolonged contact with antigen-presenting cells, and binding to target cells for killing. While the downstream signaling pathways utilized by LFA-1 are vastly conserved they allow for highly disparate responses. Here, we summarize the roles of LFA-1 and ongoing studies to better understand its functions and regulation.


Assuntos
Diferenciação Celular/genética , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Linfócitos T/citologia , Linfócitos T/fisiologia , Animais , Quimiotaxia de Leucócito/genética , Quimiotaxia de Leucócito/imunologia , Citotoxicidade Imunológica/genética , Humanos , Memória Imunológica/genética , Molécula 1 de Adesão Intercelular/química , Ativação Linfocitária/genética , Ativação Linfocitária/imunologia , Mecanotransdução Celular , Transdução de Sinais , Relação Estrutura-Atividade
16.
J Biol Chem ; 293(17): 6565-6577, 2018 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-29507098

RESUMO

In αI integrins, including leukocyte function-associated antigen 1 (LFA-1), ligand-binding function is delegated to the αI domain, requiring extra steps in the relay of signals that activate ligand binding and coordinate it with cytoplasmic signals. Crystal structures reveal great variation in orientation between the αI domain and the remainder of the integrin head. Here, we investigated the mechanisms involved in signal relay to the αI domain, including whether binding of the ligand intercellular adhesion molecule-1 (ICAM-1) to the αI domain is linked to headpiece opening and engenders a preferred αI domain orientation. Using small-angle X-ray scattering and negative-stain EM, we define structures of ICAM-1, LFA-1, and their complex, and the effect of activation by Mn2+ Headpiece opening was substantially stabilized by substitution of Mg2+ with Mn2+ and became complete upon ICAM-1 addition. These agents stabilized αI-headpiece orientation, resulting in a well-defined orientation of ICAM-1 such that its tandem Ig-like domains pointed in the opposite direction from the ß-subunit leg of LFA-1. Mutations in the integrin ßI domain α1/α1' helix stabilizing either the open or the closed ßI-domain conformation indicated that α1/α1' helix movements are linked to ICAM-1 binding by the αI domain and to the extended-open conformation of the ectodomain. The LFA-1-ICAM-1 orientation described here with ICAM-1 pointing anti-parallel to the LFA-1 ß-subunit leg is the same orientation that would be stabilized by tensile force transmitted between the ligand and the actin cytoskeleton and is consistent with the cytoskeletal force model of integrin activation.


Assuntos
Molécula 1 de Adesão Intercelular/química , Antígeno-1 Associado à Função Linfocitária/química , Magnésio/química , Manganês/química , Células HEK293 , Humanos , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Antígeno-1 Associado à Função Linfocitária/genética , Antígeno-1 Associado à Função Linfocitária/metabolismo , Magnésio/metabolismo , Manganês/metabolismo , Domínios Proteicos , Estrutura Quaternária de Proteína , Difração de Raios X
17.
Eur J Nutr ; 57(3): 877-891, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28275869

RESUMO

PURPOSE: The aim of the current meta-analysis was to investigate the effect of increasing dietary ALA intake on the blood concentration of inflammatory markers including tumor necrosis factor (TNF), interleukin 6 (IL-6), C-reactive protein (CRP), soluble intercellular adhesion molecule-1 (sICAM-1), and soluble vascular cell adhesion molecule-1 (sVCAM-1) in adults. METHODS: After a systemic search on PubMed, Embase, and Cochrane library and bibliographies of relevant articles, 25 randomized controlled trials that met the inclusion criteria were identified. RESULTS: No significant effect of dietary ALA supplementation was observed on TNF (SMD: -0.03, 95% CI -0.36 to 0.29), IL-6 (SMD: -0.17, 95% CI -0.46 to 0.12), CRP (SMD: -0.06, 95% CI -0.24 to 0.12), sICAM-1 (SMD: -0.06, 95% CI -0.26 to 0.13), and sVCAM-1 (SMD: -0.24, 95% CI -0.56 to 0.09). Subgroup analysis revealed that increasing dietary ALA tends to elevate CRP concentration in healthy subjects. However, the null effect of ALA supplementation on other inflammatory markers was not changed in various subgroups, indicating that the results are stable. Meta-regression results revealed a negative relationship between the effect size on CRP and its baseline concentration. No significant publication bias was observed for all inflammatory markers as suggested by funnel plot and Begg's test. CONCLUSION: Our meta-analysis did not find any beneficial effect of ALA supplementation on reducing inflammatory markers including TNF, IL-6, CRP, sICAM-1, and sVCAM-1. However, in healthy subjects, ALA supplementation might increase CRP concentration.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Doença Crônica/prevenção & controle , Suplementos Nutricionais , Medicina Baseada em Evidências , Mediadores da Inflamação/sangue , Ácido alfa-Linolênico/uso terapêutico , Anti-Inflamatórios não Esteroides/efeitos adversos , Biomarcadores/sangue , Proteína C-Reativa/análise , Suplementos Nutricionais/efeitos adversos , Humanos , Mediadores da Inflamação/química , Molécula 1 de Adesão Intercelular/sangue , Molécula 1 de Adesão Intercelular/química , Interleucina-6/sangue , Ensaios Clínicos Controlados Aleatórios como Assunto , Solubilidade , Fator de Necrose Tumoral alfa/sangue , Molécula 1 de Adesão de Célula Vascular/sangue , Molécula 1 de Adesão de Célula Vascular/química , Ácido alfa-Linolênico/efeitos adversos
18.
Bioconjug Chem ; 29(1): 56-66, 2018 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-29200285

RESUMO

The conjugation of antibodies to drugs and drug carriers improves delivery to target tissues. Widespread implementation and effective translation of this pharmacologic strategy awaits the development of affinity ligands capable of a defined degree of modification and highly efficient bioconjugation without loss of affinity. To date, such ligands are lacking for the targeting of therapeutics to vascular endothelial cells. To enable site-specific, click-chemistry conjugation to therapeutic cargo, we used the bacterial transpeptidase, sortase A, to attach short azidolysine containing peptides to three endothelial-specific single chain antibody fragments (scFv). While direct fusion of a recognition motif (sortag) to the scFv C-terminus generally resulted in low levels of sortase-mediated modification, improved reaction efficiency was observed for one protein, in which two amino acids had been introduced during cloning. This prompted insertion of a short, semi-rigid linker between scFv and sortag. The linker significantly enhanced modification of all three proteins, to the extent that unmodified scFv could no longer be detected. As proof of principle, purified, azide-modified scFv was conjugated to the antioxidant enzyme, catalase, resulting in robust endothelial targeting of functional cargo in vitro and in vivo.


Assuntos
Química Click/métodos , Anticorpos de Cadeia Única/química , Anticorpos de Cadeia Única/farmacocinética , Sequência de Aminoácidos , Aminoaciltransferases/metabolismo , Animais , Proteínas de Bactérias/metabolismo , Catalase/metabolismo , Linhagem Celular , Cisteína Endopeptidases/metabolismo , Humanos , Molécula 1 de Adesão Intercelular/administração & dosagem , Molécula 1 de Adesão Intercelular/química , Molécula 1 de Adesão Intercelular/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Modelos Moleculares , Molécula-1 de Adesão Celular Endotelial a Plaquetas/administração & dosagem , Molécula-1 de Adesão Celular Endotelial a Plaquetas/química , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Molécula-1 de Adesão Celular Endotelial a Plaquetas/farmacocinética , Anticorpos de Cadeia Única/administração & dosagem , Anticorpos de Cadeia Única/metabolismo , Distribuição Tecidual
19.
Arch Physiol Biochem ; 124(4): 357-360, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29183155

RESUMO

OBJECTIVE: To examine some anthropometric parameters, arterial stiffness, lipid profile, and soluble adhesion molecules in young adults with reduced physical activity. MATERIAL AND METHODS: The study is carried on 54 healthy young adults aged 20.97 ± 2.04 years. Two groups: 23 with reduced physical activity (INAC) and 31 with optimal physical activity (AC). Body mass index (BMI), basal metabolic rate (BMR), central aortic systolic blood pressure (CSBP, mmHg), plasma atherogenic index (AIP), and serum soluble cell adhesion molecules (sICAM-1, sVCAM-1) are followed up. RESULTS: CSBP [115.56 ± 10.22 vs. 105.13 ± 9.88*], AIP [-0.04 ± 0.18 vs. -0.08 ± 0.08**] and sICAM-1 [362.5 ± 49.95 vs. 281.75 ± 80.39**] are significantly higher, and BMR [1431 ± 297.9 vs. 1674.6 ± 365.57*] is significantly lower in the physically inactive young healthy adults. CONCLUSIONS: CSBP, AIP, and sICAM-1 are higher in young adults with reduced physical activity. This plays substantial role in the acceleration of atherogenic process and in long-term perspective could promote cardiovascular diseases.


Assuntos
Doenças Assintomáticas , Aterosclerose/fisiopatologia , Molécula 1 de Adesão Intercelular/sangue , Pré-Hipertensão/fisiopatologia , Comportamento Sedentário , Regulação para Cima , Rigidez Vascular , Adolescente , Adulto , Doenças Assintomáticas/epidemiologia , Doenças Assintomáticas/terapia , Aterosclerose/epidemiologia , Aterosclerose/metabolismo , Aterosclerose/prevenção & controle , Metabolismo Basal , Biomarcadores/sangue , Bulgária/epidemiologia , Exercício Físico , Seguimentos , Humanos , Molécula 1 de Adesão Intercelular/química , Pré-Hipertensão/epidemiologia , Pré-Hipertensão/metabolismo , Pré-Hipertensão/prevenção & controle , Fatores de Risco , Índice de Gravidade de Doença , Solubilidade , Estudantes de Odontologia , Estudantes de Medicina , Molécula 1 de Adesão de Célula Vascular/sangue , Molécula 1 de Adesão de Célula Vascular/química , Adulto Jovem
20.
Proc Natl Acad Sci U S A ; 115(2): 397-402, 2018 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-29284752

RESUMO

Acute hemorrhagic conjunctivitis (AHC) is a painful, contagious eye disease, with millions of cases in the last decades. Coxsackievirus A24 (CV-A24) was not originally associated with human disease, but in 1970 a pathogenic "variant" (CV-A24v) emerged, which is now the main cause of AHC. Initially, this variant circulated only in Southeast Asia, but it later spread worldwide, accounting for numerous AHC outbreaks and two pandemics. While both CV-A24 variant and nonvariant strains still circulate in humans, only variant strains cause AHC for reasons that are yet unknown. Since receptors are important determinants of viral tropism, we set out to map the CV-A24 receptor repertoire and establish whether changes in receptor preference have led to the increased pathogenicity and rapid spread of CV-A24v. Here, we identify ICAM-1 as an essential receptor for both AHC-causing and non-AHC strains. We provide a high-resolution cryo-EM structure of a virus-ICAM-1 complex, which revealed critical ICAM-1-binding residues. These data could help identify a possible conserved mode of receptor engagement among ICAM-1-binding enteroviruses and rhinoviruses. Moreover, we identify a single capsid substitution that has been adopted by all pandemic CV-A24v strains and we reveal that this adaptation enhances the capacity of CV-A24v to bind sialic acid. Our data elucidate the CV-A24v receptor repertoire and point to a role of enhanced receptor engagement in the adaptation to the eye, possibly enabling pandemic spread.


Assuntos
Conjuntivite Hemorrágica Aguda/metabolismo , Enterovirus Humano C/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , Receptores Virais/metabolismo , Sequência de Aminoácidos , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Conjuntivite Hemorrágica Aguda/epidemiologia , Conjuntivite Hemorrágica Aguda/virologia , Microscopia Crioeletrônica , Surtos de Doenças , Enterovirus Humano C/genética , Enterovirus Humano C/fisiologia , Humanos , Molécula 1 de Adesão Intercelular/química , Mutação , Ácido N-Acetilneuramínico/metabolismo , Pandemias , Filogenia , Ligação Proteica , Receptores Virais/química , Homologia de Sequência de Aminoácidos , Tropismo Viral/fisiologia
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