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1.
Proc Natl Acad Sci U S A ; 119(20): e2117381119, 2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-35533278

RESUMO

Parasitic infections are common, but how they shape ecosystem-level processes is understudied. Using a mathematical model and meta-analysis, we explored the potential for helminth parasites to trigger trophic cascades through lethal and sublethal effects imposed on herbivorous ruminant hosts after infection. First, using the model, we linked negative effects of parasitic infection on host survival, fecundity, and feeding rate to host and producer biomass. Our model, parameterized with data from a well-documented producer­caribou­helminth system, reveals that even moderate impacts of parasites on host survival, fecundity, or feeding rate can have cascading effects on ruminant host and producer biomass. Second, using meta-analysis, we investigated the links between helminth infections and traits of free-living ruminant hosts in nature. We found that helminth infections tend to exert negative but sublethal effects on ruminant hosts. Specifically, infection significantly reduces host feeding rates, body mass, and body condition but has weak and highly variable effects on survival and fecundity. Together, these findings suggest that while helminth parasites can trigger trophic cascades through multiple mechanisms, overlooked sublethal effects on nonreproductive traits likely dominate their impacts on ecosystems. In particular, by reducing ruminant herbivory, pervasive helminth infections may contribute to a greener world.


Assuntos
Helmintos , Parasitos , Animais , Ecossistema , Cadeia Alimentar , Herbivoria , Ruminantes , Simbiose
2.
J Biol Chem ; 292(10): 4185-4197, 2017 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-28154179

RESUMO

To improve our understanding of properties that confer successful inhibition of chemokines in vivo, we analyzed anti-murine CXCL10 monoclonal antibodies (mAb) having different characteristics. 1B6 displayed potent inhibition of cell recruitment in vitro with an IC50 of 0.5 nm but demonstrated little efficacy in various animal models of human disease. On the contrary, 1F11 showed efficacy in several models of inflammation yet was less potent at inhibiting chemotaxis in vitro with an IC50 of 21 nm Furthermore, we observed that 1B6 displayed a rapid dose-dependent clearance (t½ 10-60 h) in contrast to 1F11, which presented a dose-proportional pharmacokinetic profile and a half-life of 12 days. Moreover, 1B6 recognized glycosaminoglycan (GAG)-bound CXCL10, resulting in target-mediated clearance, which was corroborated using CXCL10-deficient mice. In contrast to 1B6, 1F11 inhibited the interaction of CXCL10 with GAGs, did not recognize GAG-bound CXCL10, and did not display target-mediated drug disposition. Confirming previous animal studies, 1B6 was poor at reversing glycemia in a model of type 1 diabetes, whereas 1F11 induced early and prolonged control of diabetes. Furthermore, when using 1A4, a subsequently generated anti-mCXCL10 mAb that shares the property with 1F11 of being unable to recognize CXCL10 immobilized on GAG, we observed a similar superior control of diabetes as compared with 1B6. We therefore concluded that targeting chemokines with antibodies such as 1B6 that recognize the more abundant GAG-bound form of the chemokine may not be the optimal strategy to achieve disease control.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Anticorpos Neutralizantes/administração & dosagem , Quimiocina CXCL10/antagonistas & inibidores , Diabetes Mellitus Experimental/prevenção & controle , Diabetes Mellitus Tipo 1/prevenção & controle , Endotélio Vascular/metabolismo , Glicosaminoglicanos/metabolismo , Animais , Anticorpos Monoclonais/farmacocinética , Células Cultivadas , Quimiocina CXCL10/imunologia , Quimiocina CXCL10/metabolismo , Quimiotaxia de Leucócito/fisiologia , Cricetinae , Diabetes Mellitus Experimental/imunologia , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/patologia , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/imunologia , Feminino , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Distribuição Tecidual
3.
Mol Ther ; 25(2): 523-533, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28153099

RESUMO

CD47 is a ubiquitously expressed immune checkpoint receptor that is often upregulated in cancer. CD47 interacts with its counter-receptor SIRPα on macrophages and other myeloid cells to inhibit cancer cell phagocytosis and drive immune evasion. To overcome tolerability and "antigen sink" issues arising from widespread CD47 expression, we generated dual-targeting bispecific antibodies that selectively block the CD47-SIRPα interaction on malignant cells expressing a specific tumor-associated antigen; e.g., CD19 or mesothelin. These bispecific κλ bodies are fully human, native IgG1 molecules, combining tumor targeting and selective CD47 blockade with immune activating mechanisms mediated by the Fc portion of the antibody. CD47-neutralizing κλ bodies efficiently kill cancer cells in vitro and in vivo but interact only weakly with healthy cells expressing physiological levels of CD47. Accordingly, a κλ body administered to non-human primates showed a typical IgG pharmacokinetic profile and was well tolerated. Importantly, κλ bodies preserve their tumoricidal capabilities in the presence of a CD47 antigen sink. Thus, dual-targeting κλ bodies allow for efficacious yet safe targeting of CD47 in cancer. Such a bispecific design could be applied to limit the extent of neutralization of other ubiquitously expressed therapeutic targets.


Assuntos
Anticorpos Biespecíficos/farmacologia , Antígeno CD47/metabolismo , Animais , Anticorpos Biespecíficos/imunologia , Citotoxicidade Celular Dependente de Anticorpos/imunologia , Antígenos de Neoplasias/imunologia , Antineoplásicos/farmacologia , Antígeno CD47/imunologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Humanos , Mesotelina , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Terapia de Alvo Molecular , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Neoplasias/metabolismo , Fagocitose/imunologia , Ligação Proteica/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto
4.
J Biol Chem ; 290(45): 26943-26953, 2015 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-26363066

RESUMO

The IL-6 signaling complex is described as a hexamer, formed by the association of two IL-6·IL-6 receptor (IL-6R)·gp130 trimers, with gp130 being the signal transducer inducing cis- and trans-mediated signaling via a membrane-bound or soluble form of the IL-6R, respectively. 25F10 is an anti-mouse IL-6R mAb that binds to both membrane-bound IL-6R and soluble IL-6R with the unique property of specifically inhibiting trans-mediated signaling events. In this study, epitope mapping revealed that 25F10 interacts at site IIb of IL-6R but allows the binding of IL-6 to the IL-6R and the recruitment of gp130, forming a trimer complex. Binding of 25F10 to IL-6R prevented the formation of the hexameric complex obligate for trans-mediated signaling, suggesting that the cis- and trans-modes of IL-6 signaling adopt different mechanisms for receptor complex assembly. To study this phenomenon also in the human system, we developed NI-1201, a mAb that targets, in the human IL-6R sequence, the epitope recognized by 25F10 for mice. Interestingly, NI-1201, however, did not selectively inhibit human IL-6 trans-signaling, although both mAbs produced beneficial outcomes in conditions of exacerbated IL-6 as compared with a site I-directed mAb. These findings shed light on the complexity of IL-6 signaling. First, triggering cis- versus trans-mediated IL-6 signaling occurs via distinctive mechanisms for receptor complex assembly in mice. Second, the formation of the receptor complex leading to cis- and trans-signaling biology in mice and humans is different, and this should be taken into account when developing strategies to inhibit IL-6 clinically.


Assuntos
Interleucina-6/química , Interleucina-6/metabolismo , Receptores de Interleucina-6/química , Receptores de Interleucina-6/metabolismo , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais , Receptor gp130 de Citocina/química , Receptor gp130 de Citocina/metabolismo , Feminino , Teste de Complementação Genética , Humanos , Interleucina-6/deficiência , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Camundongos Knockout , Modelos Moleculares , Dados de Sequência Molecular , Complexos Multiproteicos/química , Complexos Multiproteicos/genética , Complexos Multiproteicos/metabolismo , Células NIH 3T3 , Domínios e Motivos de Interação entre Proteínas , Multimerização Proteica , Estrutura Quaternária de Proteína , Ratos , Receptores de Interleucina-6/genética , Homologia de Sequência de Aminoácidos , Transdução de Sinais
5.
Cell Rep ; 43(2): 113776, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38367237

RESUMO

Microglia-mediated synaptic plasticity after CNS injury varies depending on injury severity, but the mechanisms that adjust synaptic plasticity according to injury differences are largely unknown. This study investigates differential actions of microglia on essential spinal motor synaptic circuits following different kinds of nerve injuries. Following nerve transection, microglia and C-C chemokine receptor type 2 signaling permanently remove Ia axons and synapses from the ventral horn, degrading proprioceptive feedback during motor actions and abolishing stretch reflexes. However, Ia synapses and reflexes recover after milder injuries (nerve crush). These different outcomes are related to the length of microglia activation, being longer after nerve cuts, with slower motor-axon regeneration and extended expression of colony-stimulating factor type 1 in injured motoneurons. Prolonged microglia activation induces CCL2 expression, and Ia synapses recover after ccl2 is deleted from microglia. Thus, microglia Ia synapse removal requires the induction of specific microglia phenotypes modulated by nerve regeneration efficiencies. However, synapse preservation was not sufficient to restore the stretch-reflex function.


Assuntos
Axônios , Microglia , Regeneração Nervosa , Receptores de Quimiocinas , Transdução de Sinais
6.
Cancer Res Commun ; 3(4): 576-591, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37066023

RESUMO

PI3K delta (PI3Kδ) inhibitors are used to treat lymphomas but safety concerns and limited target selectivity curbed their clinical usefulness. PI3Kδ inhibition in solid tumors has recently emerged as a potential novel anticancer therapy through the modulation of T-cell responses and direct antitumor activity. Here we report the exploration of IOA-244/MSC2360844, a first-in-class non-ATP-competitive PI3Kδ inhibitor, for the treatment of solid tumors. We confirm IOA-244's selectivity as tested against a large set of kinases, enzymes, and receptors. IOA-244 inhibits the in vitro growth of lymphoma cells and its activity correlates with the expression levels of PIK3CD, suggesting cancer cell-intrinsic effects of IOA-244. Importantly, IOA-244 inhibits regulatory T cell proliferation while having limited antiproliferative effects on conventional CD4+ T cells and no effect on CD8+ T cells. Instead, treatment of CD8 T cells with IOA-244 during activation, favors the differentiation of memory-like, long-lived CD8, known to have increased antitumor capacity. These data highlight immune-modulatory properties that can be exploited in solid tumors. In CT26 colorectal and Lewis lung carcinoma lung cancer models, IOA-244 sensitized the tumors to anti-PD-1 (programmed cell death protein 1) treatment, with similar activity in the Pan-02 pancreatic and A20 lymphoma syngeneic mouse models. IOA-244 reshaped the balance of tumor-infiltrating cells, favoring infiltration of CD8 and natural killer cells, while decreasing suppressive immune cells. IOA-244 presented no detectable safety concerns in animal studies and is currently in clinical phase Ib/II investigation in solid and hematologic tumors. Significance: IOA-244 is a first-in-class non-ATP-competitive, PI3Kδ inhibitor with direct antitumor in vitro activity correlated with PI3Kδ expression. The ability to modulate T cells, in vivo antitumor activity in various models with limited toxicity in animal studies provides the rationale for the ongoing trials in patients with solid tumors and hematologic cancers.


Assuntos
Linfoma , Neoplasias , Camundongos , Animais , Linfócitos T CD8-Positivos , Fosfatidilinositol 3-Quinases , Neoplasias/tratamento farmacológico , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Linfoma/tratamento farmacológico , Tolerância Imunológica
7.
Eur J Obstet Gynecol Reprod Biol ; 269: 90-97, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34979364

RESUMO

OBJECTIVE: Urinary tract infections (UTI) among women form a substantial part of medical practice and both patients and medical professionals have an interest in non-antibiotic treatments and preventative measures. This research provides preliminary data on a multi-functional composition, DAPAD, which explored several biologic activities of relevance to UTI. STUDY DESIGN: This formulation included D-mannose, citric acid, three prebiotic compounds, and extracts of dandelion and astragalus. Studies performed employed 4 bacterial strains that have relevance to UTI including E. coli, Proteus mirabilis, Streptococcus agalactiae and Enterococcus faecalis. RESULTS: Key findings from in vitro studies included: DAPAD at full- and half-strength inhibited growth of all UTI bacteria. Evidence for D-mannose agglutination of E. coli was demonstrated. D-mannose also showed unexpected effects on bacterial membrane integrity with vital staining and modest growth restriction. We did not demonstrate growth inhibition by dandelion or astragalus extracts but the latter showed diminished cytokine elaboration by bladder epithelial cells. CONCLUSION: DAPAD is a multifunctional composition that may warrant further development as a UTI treatment or preventive if supported by clinical evaluation.


Assuntos
Escherichia coli , Infecções Urinárias , Antibacterianos/uso terapêutico , Enterococcus faecalis , Feminino , Humanos , Proteus mirabilis , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/prevenção & controle
8.
G3 (Bethesda) ; 12(11)2022 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-36135804

RESUMO

Spermatogenesis is the process through which mature male gametes are formed and is necessary for the transmission of genetic information. While much work has established how sperm fate is promoted and maintained, less is known about how the sperm morphogenesis program is executed. We previously identified a novel role for the nuclear hormone receptor transcription factor, NHR-23, in promoting Caenorhabditis elegans spermatogenesis. The depletion of NHR-23 along with SPE-44, another transcription factor that promotes spermatogenesis, caused additive phenotypes. Through RNA-seq, we determined that NHR-23 and SPE-44 regulate distinct sets of genes. The depletion of both NHR-23 and SPE-44 produced yet another set of differentially regulated genes. NHR-23-regulated genes are enriched in phosphatases, consistent with the switch from genome quiescence to post-translational regulation in spermatids. In the parasitic nematode Ascaris suum, MFP1 and MFP2 control the polymerization of Major Sperm Protein, the molecule that drives sperm motility and serves as a signal to promote ovulation. NHR-23 and SPE-44 regulate several MFP2 paralogs, and NHR-23 depletion from the male germline caused defective localization of MSD/MFP1 and NSPH-2/MFP2. Although NHR-23 and SPE-44 do not transcriptionally regulate the casein kinase gene spe-6, a key regulator of sperm development, SPE-6 protein is lost following NHR-23+SPE-44 depletion. Together, these experiments provide the first mechanistic insight into how NHR-23 promotes spermatogenesis and an entry point to understanding the synthetic genetic interaction between nhr-23 and spe-44.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animais , Feminino , Masculino , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Mutação , Motilidade dos Espermatozoides , Sêmen/metabolismo , Espermatogênese/genética , Fatores de Transcrição/genética
9.
Cells ; 11(13)2022 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-35805167

RESUMO

Peripheral nerve injuries induce a pronounced immune reaction within the spinal cord, largely governed by microglia activation in both the dorsal and ventral horns. The mechanisms of activation and response of microglia are diverse depending on the location within the spinal cord, type, severity, and proximity of injury, as well as the age and species of the organism. Thanks to recent advancements in neuro-immune research techniques, such as single-cell transcriptomics, novel genetic mouse models, and live imaging, a vast amount of literature has come to light regarding the mechanisms of microglial activation and alluding to the function of microgliosis around injured motoneurons and sensory afferents. Herein, we provide a comparative analysis of the dorsal and ventral horns in relation to mechanisms of microglia activation (CSF1, DAP12, CCR2, Fractalkine signaling, Toll-like receptors, and purinergic signaling), and functionality in neuroprotection, degeneration, regeneration, synaptic plasticity, and spinal circuit reorganization following peripheral nerve injury. This review aims to shed new light on unsettled controversies regarding the diversity of spinal microglial-neuronal interactions following injury.


Assuntos
Neuralgia , Traumatismos dos Nervos Periféricos , Animais , Camundongos , Microglia , Doenças Neuroinflamatórias , Medula Espinal
10.
J Biol Chem ; 285(23): 17713-24, 2010 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-20363748

RESUMO

Chemokines orchestrate the migration of leukocytes in the context of homeostasis and inflammation. In addition to interactions of chemokines with receptors on migrating cells, these processes require interactions of chemokines with glycosaminoglycans (GAGs) for cell surface localization. Most chemokines are basic proteins with Arg/Lys/His residue clusters functioning as recognition epitopes for GAGs. In this study we characterized the GAG-binding epitopes of the chemokine I-TAC/CXCL11. Four separate clusters of basic residues were mutated to alanine and tested for their ability to bind to GAGs in vitro and to activate the receptor, CXCR3. Mutation of a set of basic residues in the C-terminal helix (the 50s cluster, (57)KSKQAR(62)) along with Lys(17), significantly impaired heparin binding in vitro, identifying these residues as components of the dominant epitope. However, this GAG mutant retained nearly wild type receptor binding affinity, and its ability to induce cell migration in vitro was only mildly perturbed. Nevertheless, the mutant was unable to induce cell migration in vivo, establishing a requirement of CXCL11 for GAG binding for in vivo function. These studies also led to some interesting findings. First, CXCL11 exhibits conformational heterogeneity, as evidenced by the doubling of peaks in its HSQC spectra. Second, it exhibits more than one affinity state for both heparin and CXCR3, which may be related to its structural plasticity. Finally, although the binding affinities of chemokines for GAGs are typically weaker than interactions with receptors, the high affinity GAG binding state of CXCL11 is comparable with typical receptor binding affinities, suggesting some unique properties of this chemokine.


Assuntos
Quimiocina CXCL11/metabolismo , Glicosaminoglicanos/química , Heparina/química , Alanina/química , Animais , Sítios de Ligação , Movimento Celular , Epitopos/química , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Mutação , Ligação Proteica , Estrutura Terciária de Proteína , Receptores CXCR3/química , Células Th1/metabolismo
11.
Immunology ; 132(4): 503-15, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21255008

RESUMO

The chemokine receptor CXCR3 and its ligands CXCL9, CXCL10 and CXCL11 are involved in variety of inflammatory disorders including multiple sclerosis, rheumatoid arthritis, psoriasis and sarcoidosis. Two alternatively spliced variants of the human CXCR3-A receptor have been described, termed CXCR3-B and CXCR3-alt. Human CXCR3-B binds CXCL9, CXCL10, CXCL11 as well as an additional ligand CXCL4. In contrast, CXCR3-alt only binds CXCL11. We report that CXCL4 induces intracellular calcium mobilization as well as Akt and p44/p42 extracellular signal-regulated kinase phosphorylation, in activated human T lymphocytes. These responses have similar concentration dependence and time-courses to those induced by established CXCR3 agonists. Moreover, phosphorylation of Akt and p44/p42 is inhibited by pertussis toxin, suggesting coupling to Gα(i) protein. Surprisingly, and in contrast with the other CXCR3 agonists, stimulation of T lymphocytes with CXCL4 failed to elicit migratory responses and did not lead to loss of surface CXCR3 expression. Taken together, our findings show that, although CXCL4 is coupled to downstream biochemical machinery, its role in T cells is probably distinct from that of CXCR3-A agonists.


Assuntos
Variação Genética , Receptores CXCR3/genética , Linfócitos T/metabolismo , Acetamidas/farmacologia , Western Blotting , Cálcio/metabolismo , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Quimiocina CXCL10/genética , Quimiocina CXCL10/farmacologia , Quimiocina CXCL11/genética , Quimiocina CXCL11/farmacologia , Quimiocina CXCL9/genética , Quimiocina CXCL9/farmacologia , Relação Dose-Resposta a Droga , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Expressão Gênica/efeitos dos fármacos , Células HEK293 , Humanos , Toxina Pertussis/farmacologia , Fosforilação/efeitos dos fármacos , Fator Plaquetário 4/genética , Fator Plaquetário 4/farmacologia , Isoformas de Proteínas/agonistas , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Pirimidinas/farmacologia , Receptores CXCR3/agonistas , Receptores CXCR3/metabolismo , Proteínas Recombinantes/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Linfócitos T/citologia , Linfócitos T/efeitos dos fármacos
12.
Stem Cells Transl Med ; 10(8): 1170-1183, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33794062

RESUMO

Craniofacial bones protect vital organs, perform important physiological functions, and shape facial identity. Critical-size defects (CSDs) in calvarial bones, which will not heal spontaneously, are caused by trauma, congenital defects, or tumor resections. They pose a great challenge for patients and physicians, and significantly compromise quality of life. Currently, calvarial CSDs are treated either by allogenic or autologous grafts, metal or other synthetic plates that are associated with considerable complications. While previous studies have explored tissue regeneration for calvarial defects, most have been done in small animal models with limited translational value. Here we define a swine calvarial CSD model and show a novel approach to regenerate high-quality bone in these defects by combining mesenchymal stem cells (MSCs) with a three-dimensional (3D)-printed osteoconductive HA/TCP scaffold. Specifically, we have compared the performance of dental pulp neural crest MSCs (DPNCCs) to bone marrow aspirate (BMA) combined with a 3D-printed HA/TCP scaffold to regenerate bone in a calvarial CSD (>7.0 cm2 ). Both DPNCCs and BMA loaded onto the 3D-printed osteoconductive scaffold support the regeneration of calvarial bone with density, compression strength, and trabecular structures similar to native bone. Our study demonstrates a novel application of an original scaffold design combined with DPNCCs or BMA to support regeneration of high-quality bone in a newly defined and clinically relevant swine calvarial CSD model. This discovery may have important impact on bone regeneration beyond the craniofacial region and will ultimately benefit patients who suffer from debilitating CSDs.


Assuntos
Células-Tronco Mesenquimais , Alicerces Teciduais , Animais , Regeneração Óssea , Humanos , Osteogênese , Qualidade de Vida , Crânio/cirurgia , Suínos , Alicerces Teciduais/química
13.
Int J Infect Dis ; 104: 510-525, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33385583

RESUMO

BACKGROUND: Human immunodeficiency virus (HIV), hepatitis C virus (HCV) and hepatitis B virus (HBV) are substantial public health threats in the region of Central Asia and the Caucasus, where the prevalence of these infections is currently rising. METHODS: A systematic review of MEDLINE, Embase and PsycINFO was conducted with no publication date or language restrictions through October 2019. Additional data were also harvested from national surveillance reports, references found in discovered sources, and other "grey" literature. It included studies conducted on high-risk populations (people who inject drugs (PWID), female sex workers (FSW), men who have sex with men (MSM), prisoners, and migrants) in Central Asia: Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, and Uzbekistan; and the Caucasus: Armenia, Azerbaijan, Georgia, and Northern Caucasus region of the Russian Federation. RESULTS: Wide ranges were noted for HIV prevalence: PWID 0-30.1%, MSM 0-25.1%, prisoners 0-22.8%, FSW 0-10.0%, and migrants 0.06-1.5%, with the highest prevalence of these high-risk groups reported in Kazakhstan (for PWID), Georgia (for MSM and prisoners) and Uzbekistan (for migrants). HCV prevalence also had a wide range: PWID 0.3-92.1%, MSM 0-18.9%, prisoners 23.8-49.7%, FSW 3.3-17.8%, and migrants 0.5-26.5%, with the highest prevalence reported in Georgia (92.1%), Kyrgyzstan (49.7%), and migrants from Tajikistan and Uzbekistan (26.5%). Similarly, HBV prevalence had a wide range: PWID 2.8-79.7%, MSM 0-22.2%, prisoners 2.7-6.2%, FSW 18.4% (one study), and migrants 0.3-15.7%. CONCLUSION: In Central Asia and the Caucasus, prevalence of HIV, HCV and HBV remains exceedingly high among selected populations, notably PWID and MSM.


Assuntos
Infecções por HIV/epidemiologia , Hepatite B/epidemiologia , Hepatite C/epidemiologia , Ásia Central/epidemiologia , Feminino , Homossexualidade Masculina , Humanos , Masculino , Prevalência , Prisioneiros , Fatores de Risco , Federação Russa/epidemiologia , Profissionais do Sexo , Minorias Sexuais e de Gênero , Transtornos Relacionados ao Uso de Substâncias/complicações , Transcaucásia/epidemiologia
14.
Cell Rep ; 37(7): 110013, 2021 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-34788605

RESUMO

Autotaxin (ATX; ENPP2) produces lysophosphatidic acid (LPA) that regulates multiple biological functions via cognate G protein-coupled receptors LPAR1-6. ATX/LPA promotes tumor cell migration and metastasis via LPAR1 and T cell motility via LPAR2, yet its actions in the tumor immune microenvironment remain unclear. Here, we show that ATX secreted by melanoma cells is chemorepulsive for tumor-infiltrating lymphocytes (TILs) and circulating CD8+ T cells ex vivo, with ATX functioning as an LPA-producing chaperone. Mechanistically, T cell repulsion predominantly involves Gα12/13-coupled LPAR6. Upon anti-cancer vaccination of tumor-bearing mice, ATX does not affect the induction of systemic T cell responses but, importantly, suppresses tumor infiltration of cytotoxic CD8+ T cells and thereby impairs tumor regression. Moreover, single-cell data from melanoma tumors are consistent with intratumoral ATX acting as a T cell repellent. These findings highlight an unexpected role for the pro-metastatic ATX-LPAR axis in suppressing CD8+ T cell infiltration to impede anti-tumor immunity, suggesting new therapeutic opportunities.


Assuntos
Linfócitos do Interstício Tumoral/metabolismo , Diester Fosfórico Hidrolases/metabolismo , Animais , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular Tumoral , Quimiotaxia/fisiologia , Feminino , Humanos , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Lisofosfolipídeos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias , Diester Fosfórico Hidrolases/fisiologia , Receptores de Ácidos Lisofosfatídicos/metabolismo , Transdução de Sinais/fisiologia , Microambiente Tumoral
15.
Trends Ecol Evol ; 35(11): 959-962, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33039158

RESUMO

Ruminant livestock are a significant contributor to global methane emissions. Infectious diseases have the potential to exacerbate these contributions by elevating methane outputs associated with animal production. With the increasing spread of many infectious diseases, the emergence of a vicious climate-livestock-disease cycle is a looming threat.


Assuntos
Doenças Transmissíveis , Gado , Animais , Clima , Doenças Transmissíveis/epidemiologia , Doenças Transmissíveis/veterinária , Metano
16.
J Leukoc Biol ; 84(4): 1101-8, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18662971

RESUMO

We demonstrated recently that P8A-CCL2, a monomeric variant of the chemokine CCL2/MCP-1, is unable to induce cellular recruitment in vivo, despite full activity in vitro. Here, we show that this variant is able to inhibit CCL2 and thioglycollate-mediated recruitment of leukocytes into the peritoneal cavity and recruitment of cells into lungs of OVA-sensitized mice. This anti-inflammatory activity translated into a reduction of clinical score in the more complex inflammatory model of murine experimental autoimmune encephalomyelitis. Several hypotheses for the mechanism of action of P8A-CCL2 were tested. Plasma exposure following s.c. injection is similar for P8A-CCL2 and wild-type (WT) CCL2, ruling out the hypothesis that P8A-CCL2 disrupts the chemokine gradient through systemic exposure. P8A-CCL2 and WT induce CCR2 internalization in vitro and in vivo; CCR2 then recycles to the cell surface, but the cells remain refractory to chemotaxis in vitro for several hours. Although the response to P8A-CCL2 is similar to WT, this finding is novel and suggests that despite the presence of the receptor on the cell surface, coupling to the signaling machinery is retarded. In contrast to CCL2, P8A-CCL2 does not oligomerize on glycosaminoglycans (GAGs). However, it retains the ability to bind GAGs and displaces endogenous JE (murine MCP-1) from endothelial surfaces. Intravital microscopy studies indicate that P8A-CCL2 prevents leukocyte adhesion, while CCL2 has no effect, and this phenomenon may be related to the mechanism. These results suggest that oligomerization-deficient chemokines can exhibit anti-inflammatory properties in vivo and may represent new therapeutic modalities.


Assuntos
Anti-Inflamatórios/farmacologia , Quimiocina CCL2/farmacologia , Quimiocinas/fisiologia , Leucócitos/fisiologia , Animais , Encéfalo/citologia , Circulação Cerebrovascular/fisiologia , Quimiocina CCL2/genética , Quimiocinas/química , Quimiotaxia de Leucócito , Feminino , Engenharia Genética , Heparina/farmacologia , Imunização , Leucócitos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/imunologia , Tioglicolatos/farmacologia
17.
Cornea ; 38(1): 8-12, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30199398

RESUMO

PURPOSE: To analyze the incidence, nature, outcomes, and complications of acute chemical eye injuries, including the incidence of limbal stem cell deficiency (LSCD) and to compare the 2 main classifications for ocular chemical injuries: Roper-Hall (RH) and Dua. METHODS: This is a prospective, consecutive, interventional single-center study between April and October 2009 of all new patients with acute chemical eye injury presenting to the Royal Victoria Infirmary eye emergency department (EED). RESULTS: Of 11,683 patients who attended the EED, 98 patients (110 eyes) presented with acute chemical eye injury (60% male). This represents an estimated annual incidence of 5.6 new cases per 100,000 population. Mean age was 36.5 years (1-78; SD 17.1 years), including 7 children (age <10 years). Fifty-one patients (52%) had work-related injuries. The most common chemical agent was alkali (78%). All 4 RH grade IV cases were unilateral, assault with ammonia, and required early amniotic membrane transplantation as per the protocol, but despite full treatment, they developed total LSCD in the affected eye. CONCLUSIONS: Acute chemical eye injuries are rare. Male patients in the working age group are more prone to work-related chemical injuries, whereas young children tend to have domestic injuries. Grade I, II, and III RH and Dua chemical injuries had a very good prognosis with topical treatment only, whereas RH grade IV (Dua grade IV-VI), mainly assaults with ammonia, progressed to total/severe LSCD despite appropriate management including early amniotic membrane transplantation. The Dua classification includes conjunctival involvement, having a greater value in predicting the final clinical outcome when grading chemical eye injuries.


Assuntos
Queimaduras Químicas/epidemiologia , Doenças da Córnea/epidemiologia , Queimaduras Oculares/epidemiologia , Limbo da Córnea/patologia , Células-Tronco/patologia , Acuidade Visual , Doença Aguda , Adolescente , Adulto , Idoso , Álcalis , Queimaduras Químicas/patologia , Criança , Pré-Escolar , Doenças da Córnea/patologia , Queimaduras Oculares/patologia , Feminino , Seguimentos , Humanos , Incidência , Lactente , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reino Unido/epidemiologia , Adulto Jovem
18.
Invest Ophthalmol Vis Sci ; 49(5): 1907-15, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18436824

RESUMO

PURPOSE: To investigate the quality of life and priorities of patients with glaucoma. METHODS: Patients diagnosed with glaucoma and no other ocular comorbidity were consecutively recruited. Clinical information was collected. Participants were asked to complete three questionnaires: EuroQuol (EQ-5D), time tradeoff (TTO), and choice-based conjoint analysis. The latter used five-attribute outcomes: (1) reading and seeing detail, (2) peripheral vision, (3) darkness and glare, (4) household chores, and (5) outdoor mobility. Visual field loss was estimated by using binocular integrated visual fields (IVFs). RESULTS: Of 84 patients invited to participate, 72 were enrolled in the study. The conjoint utilities showed that the two main priorities were "reading and seeing detail" and "outdoor mobility." This rank order was stable across all segmentations of the data by demographic or visual state. However, the relative emphasis of these priorities changed with increasing visual field loss, with concerns for central vision increasing, whereas those for outdoor mobility decreased. Two subgroups of patients with differing priorities on the two main attributes were identified. Only 17% of patients (those with poorer visual acuity) were prepared to consider TTO. A principal component analysis revealed relatively independent components (i.e., low correlations) between the three different methodologies for assessing quality of life. CONCLUSIONS: Assessments of quality of life using different methodologies have been shown to produce different outcomes with low intercorrelations between them. Only a minority of patients were prepared to trade time for a return to normal vision. Conjoint analysis showed two subgroups with different priorities. Severity of glaucoma influenced the relative importance of priorities.


Assuntos
Glaucoma/fisiopatologia , Prioridades em Saúde , Qualidade de Vida , Campos Visuais , Atividades Cotidianas , Idoso , Feminino , Ofuscação , Indicadores Básicos de Saúde , Humanos , Masculino , Leitura , Inquéritos e Questionários , Transtornos da Visão/fisiopatologia , Acuidade Visual
19.
Mol Cancer Ther ; 17(8): 1739-1751, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29743205

RESUMO

CD47, an ubiquitously expressed innate immune checkpoint receptor that serves as a universal "don't eat me" signal of phagocytosis, is often upregulated by hematologic and solid cancers to evade immune surveillance. Development of CD47-targeted modalities is hindered by the ubiquitous expression of the target, often leading to rapid drug elimination and hemotoxicity including anemia. To overcome such liabilities, we have developed a fully human bispecific antibody, NI-1701, designed to coengage CD47 and CD19 selectively on B cells. NI-1701 demonstrates favorable elimination kinetics with no deleterious effects seen on hematologic parameters following single or multiple administrations to nonhuman primates. Potent in vitro and in vivo activity is induced by NI-1701 to kill cancer cells across a plethora of B-cell malignancies and control tumor growth in xenograft mouse models. The mechanism affording maximal tumor growth inhibition by NI-1701 is dependent on the coengagement of CD47/CD19 on B cells inducing potent antibody-dependent cellular phagocytosis of the targeted cells. NI-1701-induced control of tumor growth in immunodeficient NOD/SCID mice was more effective than that achieved with the anti-CD20 targeted antibody, rituximab. Interestingly, a synergistic effect was seen when tumor-implanted mice were coadministered NI-1701 and rituximab leading to significantly improved tumor growth inhibition and regression in some animals. We describe herein, a novel bispecific antibody approach aimed at sensitizing B cells to become more readily phagocytosed and eliminated thus offering an alternative or adjunct therapeutic option to patients with B-cell malignancies refractory/resistant to anti-CD20-targeted therapy. Mol Cancer Ther; 17(8); 1739-51. ©2018 AACR.


Assuntos
Anticorpos Biespecíficos/genética , Leucemia/genética , Leucemia/terapia , Linfoma de Células B/genética , Linfoma de Células B/terapia , Animais , Antígenos CD19 , Antígeno CD47 , Humanos , Leucemia/patologia , Linfoma de Células B/patologia , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Biochem Soc Symp ; (74): 129-39, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17233586

RESUMO

PtdIns(3,5)P2 was discovered about a decade ago and much of the machinery that makes, degrades and senses it has been uncovered. Despite this, we still lack a complete understanding of how the pieces fit together but some patterns are beginning to emerge. Molecular functions for PtdIns(3,5)P2 are also elusive, but the identification of effectors offers a way into some of these processes. An examination of the defects associated with loss of synthesis of PtdIns(3,5)P2 in lower and higher eukaryotes begins to suggest a unifying theme; this lipid regulates membrane retrieval via retrograde trafficking from distal compartments to organelles that are more proximal in the endocytic/lysosomal system. Another unifying theme is stress signalling to organelles, possibly both to change their morphology in response to external insults and to maintain the lumenal pH or membrane potential of organelles. The next few years seem likely to uncover details of the molecular mechanisms underlying the biology of this fascinating lipid. This review also highlights some areas where further research is needed.


Assuntos
Fosfatos de Fosfatidilinositol/metabolismo , Animais , Drosophila/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Modelos Biológicos , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
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