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2.
Sci Rep ; 14(1): 292, 2024 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-38167636

RESUMEN

The chemokine receptor CCR5 is known to exist in cell surface subpopulations that differ in their capacity to engage ligands. One proposed explanation for this phenomenon is the presence of CCR5 species with different levels of post-translational modifications (PTMs). Tyrosine sulfation and O-glycan sialylation are PTMs that add negative charges to the extracellular domain of CCR5 and make strong contributions to chemokine binding but it is not known whether cellular mechanisms to control their levels exist. In this study we used a combination of sulfation-sensitive and sulfation-insensitive CCR5 ligands to show that the rate of turnover of CCR5 tyrosine sulfation is more rapid than the rate of turnover of the receptor itself. This suggests that the steady state level of CCR5 sulfation is maintained through the combination of tyrosine protein sulfotransferase (TPST), the trans-Golgi network (TGN)-resident 'source enzyme, and a 'sink' activity that removes tyrosine sulfation from CCR5. By measuring the effects on ligand binding of knockdown and overexpression experiments, we provided evidence that non-lysosomal cellular arylsulfatases, particularly ARSG, ARSI and ARSJ, are CCR5 sulfation 'sink' enzymes. We also used targeted knockdown and sialylation-sensitive and insensitive chemokines to identify the sialidase NEU3 as a candidate 'sink' enzyme for CCR5 O-glycan sialylation. This study provides the first experimental evidence of activity of sulfatase and sialidase 'sink' enzymes on CCR5, providing a potential mechanism for cells to control steady-state levels of these PTMs and thereby exert dynamic control over receptor-ligand interactions at the cell surface and during receptor desensitization.


Asunto(s)
Arilsulfatasas , Neuraminidasa , Ligandos , Electricidad Estática , Quimiocinas , Tirosina/metabolismo , Polisacáridos , Receptores CCR5/metabolismo
3.
Proc Natl Acad Sci U S A ; 120(21): e2214936120, 2023 05 23.
Artículo en Inglés | MEDLINE | ID: mdl-37192162

RESUMEN

Influenza A virus (IAV) enters host cells mostly through clathrin-dependent receptor-mediated endocytosis. A single bona fide entry receptor protein supporting this entry mechanism remains elusive. Here we performed proximity ligation of biotin to host cell surface proteins in the vicinity of attached trimeric hemagglutinin-HRP and characterized biotinylated targets using mass spectrometry. This approach identified transferrin receptor 1 (TfR1) as a candidate entry protein. Genetic gain-of-function and loss-of-function experiments, as well as in vitro and in vivo chemical inhibition, confirmed the functional involvement of TfR1 in IAV entry. Recycling deficient mutants of TfR1 do not support entry, indicating that TfR1 recycling is essential for this function. The binding of virions to TfR1 via sialic acids confirmed its role as a directly acting entry factor, but unexpectedly even headless TfR1 promoted IAV particle uptake in trans. TIRF microscopy localized the entering virus-like particles in the vicinity of TfR1. Our data identify TfR1 recycling as a revolving door mechanism exploited by IAV to enter host cells.


Asunto(s)
Virus de la Influenza A , Transferrina , Virus de la Influenza A/fisiología , Internalización del Virus , Endocitosis/fisiología , Receptores de Transferrina/genética , Receptores de Transferrina/metabolismo
4.
Front Immunol ; 14: 1155200, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37063899

RESUMEN

Introduction: C-type lectin receptor (CLR) agonists emerged as superior inducers of primary B cell responses in early life compared with Toll-like receptor (TLR) agonists, while both types of adjuvants are potent in adults. Methods: Here, we explored the mechanisms accounting for the differences in neonatal adjuvanticity between a CLR-based (CAF®01) and a TLR4-based (GLA-SE) adjuvant administered with influenza hemagglutinin (HA) in neonatal mice, by using transcriptomics and systems biology analyses. Results: On day 7 after immunization, HA/CAF01 increased IL6 and IL21 levels in the draining lymph nodes, while HA/GLA-SE increased IL10. CAF01 induced mixed Th1/Th17 neonatal responses while T cell responses induced by GLA-SE had a more pronounced Th2-profile. Only CAF01 induced T follicular helper (Tfh) cells expressing high levels of IL21 similar to levels induced in adult mice, which is essential for germinal center (GC) formation. Accordingly, only CAF01- induced neonatal Tfh cells activated adoptively transferred hen egg lysozyme (HEL)-specific B cells to form HEL+ GC B cells in neonatal mice upon vaccination with HEL-OVA. Discussion: Collectively, the data show that CLR-based adjuvants are promising neonatal and infant adjuvants due to their ability to harness Tfh responses in early life.


Asunto(s)
Linfocitos B , Centro Germinal , Lectinas Tipo C , Células T Auxiliares Foliculares , Animales , Ratones , Adyuvantes Inmunológicos/farmacología , Lectinas Tipo C/agonistas , Animales Recién Nacidos
5.
Eur J Clin Invest ; 51(11): e13661, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34324704

RESUMEN

BACKGROUND: Unravelling autoimmune targets triggered by SARS-CoV-2 infection may provide crucial insights into the physiopathology of the disease and foster the development of potential therapeutic candidate targets and prognostic tools. We aimed at determining (a) the association between anti-SARS-CoV-2 and anti-apoA-1 humoral response and (b) the degree of linear homology between SARS-CoV-2, apoA-1 and Toll-like receptor 2 (TLR2) epitopes. DESIGN: Bioinformatics modelling coupled with mimic peptides engineering and competition experiments were used to assess epitopes sequence homologies. Anti-SARS-CoV-2 and anti-apoA-1 IgG as well as cytokines were assessed by immunoassays on a case-control (n = 101), an intensive care unit (ICU; n = 126) and a general population cohort (n = 663) with available samples in the pre and post-pandemic period. RESULTS: Using bioinformatics modelling, linear sequence homologies between apoA-1, TLR2 and Spike epitopes were identified but without experimental evidence of cross-reactivity. Overall, anti-apoA-1 IgG levels were higher in COVID-19 patients or anti-SARS-CoV-2 seropositive individuals than in healthy donors or anti-SARS-CoV-2 seronegative individuals (P < .0001). Significant and similar associations were noted between anti-apoA-1, anti-SARS-CoV-2 IgG, cytokines and lipid profile. In ICU patients, anti-SARS-CoV-2 and anti-apoA-1 seroconversion rates displayed similar 7-day kinetics, reaching 82% for anti-apoA-1 seropositivity. In the general population, SARS-CoV-2-exposed individuals displayed higher anti-apoA-1 IgG seropositivity rates than nonexposed ones (34% vs 16.8%; P = .004). CONCLUSION: COVID-19 induces a marked humoral response against the major protein of high-density lipoproteins. As a correlate of poorer prognosis in other clinical settings, such autoimmunity signatures may relate to long-term COVID-19 prognosis assessment and warrant further scrutiny in the current COVID-19 pandemic.


Asunto(s)
Anticuerpos Antivirales/inmunología , Apolipoproteína A-I/inmunología , Autoanticuerpos/inmunología , COVID-19/inmunología , Citocinas/inmunología , Inmunidad Humoral/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Apolipoproteína A-I/química , Biología Computacional , Epítopos/química , Femenino , Humanos , Inmunoglobulina G/inmunología , Masculino , Persona de Mediana Edad , Fragmentos de Péptidos/química , Fragmentos de Péptidos/inmunología , Péptidos , SARS-CoV-2 , Homología de Secuencia de Aminoácido , Glicoproteína de la Espiga del Coronavirus/química , Receptor Toll-Like 2/química , Receptor Toll-Like 2/inmunología , Adulto Joven
6.
Chimia (Aarau) ; 75(6): 489-494, 2021 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-34233810

RESUMEN

Numerous members of the human G protein-coupled receptor (GPCR) superfamily are receptors of therapeutic interest. GPCRs are considered to be highly tractable for drug discovery, representing the targets of approximately one-third of currently licensed drugs. These successful drug discovery outcomes cover only a relatively small subset of the superfamily, however, and many other attractive receptors have proven to present significant challenges. Among these difficult GPCRs are those whose natural ligands are peptides and proteins. In this review we explain the obstacles faced by GPCR drug discovery campaigns, with particular focus on those related to peptide and protein GPCRs. We describe a novel and promising approach for these targets based on engineering of their natural ligands and describe an integrated discovery platform that allows potent ligand analogs to be discovered rapidly and efficiently. Finally, we present a case study involving the chemokine receptor CCR5 to show that this approach can be used to generate new drugs for peptide and protein GPCR targets combining best-in-class potency with tunable signaling activity.


Asunto(s)
Péptidos , Receptores Acoplados a Proteínas G , Descubrimiento de Drogas , Humanos , Ligandos , Transducción de Señal
7.
Sci Adv ; 7(25)2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34134983

RESUMEN

The human CC chemokine receptor 5 (CCR5) is a G protein-coupled receptor (GPCR) that plays a major role in inflammation and is involved in cancer, HIV, and COVID-19. Despite its importance as a drug target, the molecular activation mechanism of CCR5, i.e., how chemokine agonists transduce the activation signal through the receptor, is yet unknown. Here, we report the cryo-EM structure of wild-type CCR5 in an active conformation bound to the chemokine super-agonist [6P4]CCL5 and the heterotrimeric Gi protein. The structure provides the rationale for the sequence-activity relation of agonist and antagonist chemokines. The N terminus of agonist chemokines pushes onto specific structural motifs at the bottom of the orthosteric pocket that activate the canonical GPCR microswitch network. This activation mechanism differs substantially from other CC chemokine receptors that bind chemokines with shorter N termini in a shallow binding mode involving unique sequence signatures and a specialized activation mechanism.


Asunto(s)
Receptores CCR5/química , Receptores CCR5/metabolismo , Quimiocina CCL5/química , Quimiocina CCL5/metabolismo , Microscopía por Crioelectrón , Humanos , Modelos Moleculares , Simulación de Dinámica Molecular , Conformación Proteica , Receptores CCR5/agonistas , Receptores CCR5/genética , Transducción de Señal , Relación Estructura-Actividad
8.
AIDS Res Hum Retroviruses ; 37(6): 453-460, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33749321

RESUMEN

OB-002 is an extremely potent CCR5 antagonist that has previously been shown to completely block transmission in a nonhuman primate model of HIV infection. The purpose of this study was to characterize the safety, acceptability, and pharmacokinetic profile of a gel formulation of OB-002 (OB-002H). The trial had two phases, an open label single dose exposure (vaginal and rectal) and a randomized placebo controlled multiple dose phase during which study participants received five vaginal daily doses of OB-002H gel or matched placebo in a 2:1 ratio. Serum OB-002 levels were quantified at multiple time points up to 24 h after the first dose. A total of thirty female and male participants were enrolled in the study (12 in the single dose phase and 18 in the multiple dose phase). All adverse events were Grade 1 or 2, and the majority was unrelated to study product. Only two product-related transient Grade 2 events (both vulval dryness) occurred in the study, both in the OB-002H gel randomized multiple dose arm. All colposcopic and anoscopic assessments following product exposure were normal. There was no evidence of systemic absorption of OB-002. Overall, the product had a positive acceptability profile, and most study participants would consider using the product for protection against HIV or pregnancy. Future studies are needed to assess the extended safety and acceptability of OB-002H gel in sexually active participants. Clinical Trial Registration Number: NCT04791007.


Asunto(s)
Infecciones por VIH , Animales , Método Doble Ciego , Femenino , Infecciones por VIH/tratamiento farmacológico , Voluntarios Sanos , Humanos , Masculino , Embarazo , Recto , Vagina
9.
Clin Transl Immunology ; 9(12): e1220, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33343896

RESUMEN

OBJECTIVES: Autoantibodies against apolipoprotein A1 (anti-apoA1 IgGs) and its C-terminal region (cter apoA1) have emerged as an independent biomarker for cardiovascular disease. Cter apoA1 mimetic peptides were shown to reverse the deleterious anti-apoA1 IgG effects in vitro. We evaluated the association of anti-cter apoA1 IgGs with overall mortality in the general population and tested the ability of a cter apoA1 mimetic peptide to reverse the anti-apoA1 IgG-induced inflammatory response and mortality in vitro and in vivo, respectively. METHODS: Anti-cter apoA1 IgGs were measured in serum samples of 6386 participants of the CoLaus study of which 5220 were followed for a median duration of 5.6 years. The primary outcome was overall mortality. The peptide inhibitory concentration 50% (IC50) was determined in vitro on HEK-Blue-4 and RAW cells. ApoE-/- mice were exposed to 16 weeks of anti-apoA1IgG passive immunisation with and without peptide co-incubation. RESULTS: Anti-cter apoA1 IgGs were associated with higher interleukin 6 levels and independently predicted overall mortality; an increase of one standard deviation of anti-cter apoA1 IgG level was associated with an 18% increase in mortality risk (hazard ratio: 1.18, 95% confidence interval: 1.04-1.33; P = 0.009). The cterApoA1 analogue reversed the antibody-mediated inflammatory response with an IC50 of 1 µm in vitro but did not rescue the significant anti-apoA1 IgG-induced mortality rate in vivo (69% vs. 23%, LogRank P = 0.02). CONCLUSION: Anti-cter apoA1 IgG independently predicts overall mortality in the general population. Despite being effective in vitro, our cter apoA1 analogue did not reverse the anti-apoA1 IgG-induced mortality in mice. Our data suggest that these autoantibodies are not readily treatable through cognate peptide immunomodulation.

10.
Praxis (Bern 1994) ; 109(11): 871-878, 2020 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-32873171

RESUMEN

Studying Human Medicine at the University of Geneva: An Up-to-Date, Integrated Curriculum Abstract. The curriculum of human medicine at the Faculty of Medicine of the University of Geneva has been thoroughly renovated in 1995. It offers an integrated program allowing for a constant adaptation of the content to the explosion of biomedical knowledge and the changes in society. It uses active, student-centred learning methods. In line with the Bologna process since 2006, it has been accredited several times, most recently in 2019. It evolved to strengthen the importance of primary care and to introduce interprofessional training, in particular through its simulation centre. Through early and continuous clinical immersion, students acquire their practical skills in an integrated manner. These conditions are conducive to the introduction of new concepts, such as the Entrustable Professional Activities (EPAs) conveyed by the recent national competence framework PROFILES.


Résumé. Le curriculum de médecine humaine de la faculté de médecine de l'Université de Genève a été complètement rénové en 1995 et propose un programme d'études intégré garantissant une adaptation constante du contenu de son enseignement à l'explosion des connaissances biomédicales et aux mutations de la société, en utilisant des méthodes d'apprentissage actif, centrées sur l'étudiant-e. Conforme au processus de Bologne depuis 2006, il a été accrédité à plusieurs reprises, la dernière fois en 2019. Il s'est adapté pour renforcer l'enseignement de la médecine de premier recours et introduire des formations interprofessionnelles, notamment grâce à son centre de simulation. Grâce à une immersion clinique précoce et continue, les étudiant-es acquièrent de façon intégrée leurs compétences pratiques. Ces conditions sont favorables à l'introduction de nouveaux concepts, tels les Entrustable Professional Activities (EPAs) véhiculés par le récent référentiel national d'apprentissage PROFILES.


Asunto(s)
Curriculum , Medicina , Competencia Clínica , Humanos , Atención Primaria de Salud , Suiza
11.
Mol Pharmacol ; 98(5): 599-611, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32943494

RESUMEN

C-C chemokine receptor 5 (CCR5) is a chemokine receptor belonging to the G protein-coupled receptor (GPCR) superfamily. An established anti-human immunodeficiency virus drug target, CCR5 is attracting significant additional interest in both cancer and neuroinflammation. Several N-terminally engineered analogs of C-C chemokine ligand 5 (CCL5), a natural ligand of CCR5, are highly potent CCR5 inhibitors. The inhibitory mechanisms of certain analogs relate to modulation of receptor desensitization, but the cellular and molecular mechanisms have not been fully elucidated. Here we made use of a collection of CCR5 phosphorylation mutants and arrestin variants to investigate how CCL5 analogs differ from CCL5 in their capacity to elicit both CCR5 phosphorylation and arrestin recruitment, with reference to the current "core" and "tail" interaction model for arrestin-GPCR interaction. We showed that CCL5 recruits both arrestin 2 and arrestin 3 to CCR5 with recruitment, particularly of arrestin 2, strongly dependent on the arrestin tail interaction. 5P12-RANTES does not elicit receptor phosphorylation or arrestin recruitment. In contrast, PSC-RANTES induces CCR5 hyperphosphorylation, driving enhanced arrestin recruitment with lower dependence on the arrestin tail interaction. 5P14-RANTES induces comparable levels of receptor phosphorylation to CCL5, but arrestin recruitment is absolutely dependent on the arrestin tail interaction, and in one of the cellular backgrounds used, recruitment showed isoform bias toward arrestin 3 versus arrestin 2. No evidence for ligand-specific differences in receptor phosphorylation patterns across the four implicated serine residues was observed. Our results improve understanding of the molecular pharmacology of CCR5 and help further elucidate the inhibitory mechanisms of a group of potent inhibitors. SIGNIFICANCE STATEMENT: C-C chemokine receptor 5 (CCR5) is a key drug target for human immunodeficiency virus, cancer, and inflammation. Highly potent chemokine analog inhibitors act via the modulation of receptor desensitization, a process initiated by the recruitment of arrestin proteins. This study shows that potent C-C chemokine ligand 5 analogs differ from each other and from the parent chemokine in the extent and quality of CCR5-arrestin association that they elicit, providing valuable insights into CCR5 pharmacology and cell biology that will facilitate the development of new medicines targeting this important receptor.


Asunto(s)
Arrestina/metabolismo , Quimiocina CCL5/metabolismo , Quimiocinas CC/metabolismo , Fosforilación/fisiología , Isoformas de Proteínas/metabolismo , Animales , Arrestinas/metabolismo , Células CHO , Línea Celular , Quimiocinas/metabolismo , Cricetulus , Células HEK293 , Humanos , Ligandos , Receptores de Quimiocina/metabolismo , Transducción de Señal/fisiología , beta-Arrestina 1/metabolismo
12.
Biophys J ; 117(5): 903-919, 2019 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-31421836

RESUMEN

The chemokine receptor CCR5 is a drug target to prevent transmission of HIV/AIDS. We studied four analogs of the native chemokine regulated, on activation, normal T-cell-expressed, and secreted (RANTES) (CCL5) that have anti-HIV potencies of around 25 pM, which is more than four orders of magnitude higher than that of RANTES itself. It has been hypothesized that the ultrahigh potency of the analogs is due to their ability to bind populations of receptors not accessible to native chemokines. To test this hypothesis, we developed a homogeneous dual-color fluorescence cross-correlation spectroscopy assay for saturation- and competition-binding experiments. The fluorescence cross-correlation spectroscopy assay has the advantage that it does not rely on competition with radioactively labeled native chemokines used in conventional assays. We prepared site-specifically labeled fluorescent analogs using native chemical ligation of synthetic peptides, followed by bioorthogonal fluorescent labeling. We engineered a mammalian cell expression construct to provide fluorescently labeled CCR5, which was purified using a tandem immunoaffinity and size-exclusion chromatography approach to obtain monomeric fluorescent CCR5 in detergent solution. We found subnanomolar binding affinities for the two analogs 5P12-RANTES and 5P14-RANTES and about 20-fold reduced affinities for PSC-RANTES and 6P4-RANTES. Using homologous and heterologous competition experiments with unlabeled chemokine analogs, we conclude that the analogs all bind at the same binding site, whereas the native chemokines (RANTES and MIP-1α) fail to displace bound fluorescent analogs even at tens of micromolar concentrations. Our results can be rationalized with de novo structural models of the N-terminal tails of the synthetic chemokines that adopt a different binding mode as compared to the parent compound.


Asunto(s)
Quimiocinas/metabolismo , VIH-1/metabolismo , Receptores CCR5/metabolismo , Unión Competitiva , Quimiocina CCL5/metabolismo , Células HEK293 , Humanos , Ligandos , Modelos Biológicos , Unión Proteica
13.
Sci Transl Med ; 11(498)2019 06 26.
Artículo en Inglés | MEDLINE | ID: mdl-31243152

RESUMEN

Epidemiological studies associate viral infections during childhood with the risk of developing autoimmune disease during adulthood. However, the mechanistic link between these events remains elusive. We report that transient viral infection of the brain in early life, but not at a later age, precipitates brain autoimmune disease elicited by adoptive transfer of myelin-specific CD4+ T cells at sites of previous infection in adult mice. Early-life infection of mouse brains imprinted a chronic inflammatory signature that consisted of brain-resident memory T cells expressing the chemokine (C-C motif) ligand 5 (CCL5). Blockade of CCL5 signaling via C-C chemokine receptor type 5 prevented the formation of brain lesions in a mouse model of autoimmune disease. In mouse and human brain, CCL5+ TRM were located predominantly to sites of microglial activation. This study uncovers how transient brain viral infections in a critical window in life might leave persisting chemotactic cues and create a long-lived permissive environment for autoimmunity.


Asunto(s)
Enfermedades Autoinmunes/inmunología , Encéfalo/inmunología , Memoria Inmunológica , Linfocitos T/inmunología , Animales , Células Presentadoras de Antígenos/inmunología , Quimiocina CCL5/metabolismo , Susceptibilidad a Enfermedades , Antígenos HLA-DR/metabolismo , Humanos , Virus de la Coriomeningitis Linfocítica/inmunología , Ratones Endogámicos C57BL , Esclerosis Múltiple/inmunología , Esclerosis Múltiple/patología
14.
JCI Insight ; 4(7)2019 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-30944244

RESUMEN

Paraneoplastic neurological disorders result from an autoimmune response against neural self-antigens that are ectopically expressed in neoplastic cells. In paraneoplastic disorders associated to autoantibodies against intracellular proteins, such as paraneoplastic cerebellar degeneration (PCD), current data point to a major role of cell-mediated immunity. In an animal model, in which a neo-self-antigen was expressed in both Purkinje neurons and implanted breast tumor cells, immune checkpoint blockade led to complete tumor control at the expense of cerebellum infiltration by T cells and Purkinje neuron loss, thereby mimicking PCD. Here, we identify 2 potential therapeutic targets expressed by cerebellum-infiltrating T cells in this model, namely α4 integrin and IFN-γ. Mice with PCD were treated with anti-α4 integrin antibodies or neutralizing anti-IFN-γ antibodies at the onset of neurological signs. Although blocking α4 integrin had little or no impact on disease development, treatment using the anti-IFN-γ antibody led to almost complete protection from PCD. These findings strongly suggest that the production of IFN-γ by cerebellum-invading T cells plays a major role in Purkinje neuron death. Our successful preclinical use of neutralizing anti-IFN-γ antibody for the treatment of PCD offers a potentially new therapeutic opportunity for cancer patients at the onset of paraneoplastic neurological disorders.


Asunto(s)
Interferón gamma/antagonistas & inhibidores , Neoplasias Mamarias Experimentales/complicaciones , Degeneración Cerebelosa Paraneoplásica/tratamiento farmacológico , Células de Purkinje/patología , Linfocitos T/efectos de los fármacos , Animales , Antígenos de Neoplasias/inmunología , Autoanticuerpos/inmunología , Autoantígenos/inmunología , Línea Celular Tumoral/trasplante , Femenino , Integrina alfa4/antagonistas & inhibidores , Integrina alfa4/inmunología , Integrina alfa4/metabolismo , Interferón gamma/inmunología , Interferón gamma/metabolismo , Neoplasias Mamarias Experimentales/inmunología , Ratones , Ratones Noqueados , Degeneración Cerebelosa Paraneoplásica/inmunología , Degeneración Cerebelosa Paraneoplásica/patología , Células de Purkinje/inmunología , Células de Purkinje/metabolismo , Linfocitos T/inmunología , Linfocitos T/metabolismo
15.
Int J Pharm ; 564: 207-213, 2019 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-30999049

RESUMEN

The past fifteen years have witnessed a resurgence of interest in vaginal ring technologies for drug delivery applications, mostly driven by the impetus for development of vaginally-administered antiretroviral microbicides to help reduce the high acquisition rates for human immunodeficiency virus (HIV) among Sub-Saharan African women. Currently, the lead candidate microbicide is a 28-day silicone elastomer vaginal ring releasing dapivirine (Ring-004), an experimental non-nucleoside reverse transcriptase inhibitor. The ring was tested in two pivotal Phase III clinical studies in 2016 and is currently undergoing review by the European Medicines Agency. Recently, we described a new type of silicone elastomer vaginal ring offering sustained release of the protein molecule 5P12-RANTES, a potent experimental chemokine analogue that potently blocks the HIV CCR5 coreceptor. Building on our previous work, here we report the preclinical development of a new combination vaginal ring that offers sustained release of both 5P12-RANTES and dapivirine, in which the 5P12-RANTES is incorporated into an exposed core within the ring body and the dapivirine in the sheath. In this way, in vitro release of dapivirine matches closely that for Ring-004. Also, we report the pharmacokinetic testing of this combination ring formulation in sheep, where vaginal concentrations of both drugs are maintained over 28 days at levels potentially useful for preventing HIV infection in women.


Asunto(s)
Fármacos Anti-VIH/administración & dosificación , Quimiocinas CC/administración & dosificación , Dispositivos Anticonceptivos Femeninos , Infecciones por VIH/prevención & control , Pirimidinas/administración & dosificación , Animales , Fármacos Anti-VIH/farmacocinética , Quimiocinas CC/farmacocinética , Preparaciones de Acción Retardada/administración & dosificación , Combinación de Medicamentos , Femenino , Pirimidinas/farmacocinética , Ovinos , Vagina/metabolismo
16.
J Control Release ; 298: 1-11, 2019 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-30731150

RESUMEN

Antiretroviral-releasing vaginal rings are at the forefront of ongoing efforts to develop microbicide-based strategies for prevention of heterosexual transmission of the human immunodeficiency virus (HIV). However, traditional ring designs are generally only useful for vaginal administration of relatively potent, lipophilic, and small molecular weight drug molecules that have sufficient permeability in the non-biodegradable silicone elastomer or thermoplastic polymers. Here, we report a novel, easy-to-manufacture 'exposed-core' vaginal ring that provides sustained release of the protein microbicide candidate 5P12-RANTES, an experimental chemokine analogue that potently blocks the HIV CCR5 coreceptor. In vitro release, mechanical, and stability testing demonstrated the utility and practicality of this novel ring design. In a sheep pharmacokinetic model, a ring containing two »-length excipient-modified silicone elastomer cores - each containing lyophilised 5P12-RANTES and exposed to the external environment by two large windows - provided sustained concentrations of 5P12-RANTES in vaginal fluid and vaginal tissue between 10 and 10,000 ng/g over 28days, at least 50 and up to 50,000 times the reported in vitro IC50 value.


Asunto(s)
Antagonistas de los Receptores CCR5/administración & dosificación , Quimiocinas CC/administración & dosificación , Dispositivos Anticonceptivos Femeninos , Sistemas de Liberación de Medicamentos , Administración Intravaginal , Animales , Fármacos Anti-VIH/administración & dosificación , Fármacos Anti-VIH/farmacocinética , Antagonistas de los Receptores CCR5/farmacocinética , Quimiocinas CC/farmacocinética , Preparaciones de Acción Retardada , Femenino , Infecciones por VIH/prevención & control , Humanos , Concentración 50 Inhibidora , Ovinos
17.
J Biol Chem ; 293(49): 19092-19100, 2018 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-30305389

RESUMEN

Peptides represent a promising source of new medicines, but improved technologies are needed to facilitate discovery and optimization campaigns. In particular, longer peptides with multiple disulfide bridges are challenging to produce, and producing large numbers of structurally related variants is dissuasively costly and time-consuming. The principal cost and time drivers are the multiple column chromatography purification steps that are used during the multistep chemical synthesis procedure, which involves both ligation and oxidative refolding steps. In this study, we developed a method for multiplex parallel synthesis of complex peptide analogs in which the structurally variant region of the molecule is produced as a small peptide on a 384-well synthesizer with subsequent ligation to the longer, structurally invariant region and oxidative refolding carried out in-well without any column purification steps. To test the method, we used a panel of 96 analogs of the chemokine RANTES (regulated on activation normal T cell expressed and secreted)/CCL5 (69 residues, two disulfide bridges), which had been synthesized using standard approaches and characterized pharmacologically in an earlier study. Although, as expected, the multiplex method generated chemokine analogs of lower purity than those produced in the original study, it was nonetheless possible to closely match the pharmacological attributes (anti-HIV potency, capacity to elicit G protein signaling, and capacity to elicit intracellular receptor sequestration) of each chemokine analog to reference data from the earlier study. This rapid, low-cost approach has the potential to support discovery and optimization campaigns based on analogs of other chemokines as well as those of other complex peptide and small protein targets of a similar size.


Asunto(s)
Quimiocina CCL5/síntesis química , Animales , Fármacos Anti-VIH/síntesis química , Fármacos Anti-VIH/química , Fármacos Anti-VIH/farmacología , Células CHO , Técnicas de Química Sintética/economía , Técnicas de Química Sintética/métodos , Quimiocina CCL5/química , Quimiocina CCL5/farmacología , Cricetulus , Células HEK293 , Humanos , Oxidación-Reducción , Pliegue de Proteína , Receptores CCR5/agonistas
18.
Cytokine ; 109: 81-93, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29903576

RESUMEN

Because of the level of attention it received due to its role as the principal HIV coreceptor, CCR5 has been described as a 'celebrity' chemokine receptor. Here we describe the development of CCR5 inhibitory strategies that have been developed for HIV therapy and which are now additionally being considered for use in HIV prevention and cure. The wealth of CCR5-related tools that have been developed during the intensive investigation of CCR5 as an HIV drug target can now be turned towards the study of CCR5 as a model chemokine receptor. We also summarize what is currently known about the cell biology and pharmacology of CCR5, providing an update on new areas of investigation that have emerged in recent research. Finally, we discuss the potential of CCR5 as a drug target for diseases other than HIV, discussing the evidence linking CCR5 and its natural chemokine ligands with inflammatory diseases, particularly neuroinflammation, and certain cancers. These pathologies may provide new uses for the strategies for CCR5 blockade originally developed to combat HIV/AIDS.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/prevención & control , VIH-1/metabolismo , Receptores CCR5/metabolismo , Receptores del VIH/antagonistas & inhibidores , Receptores del VIH/metabolismo , Humanos , Inflamación/patología , Transducción de Señal/fisiología
19.
Swiss Med Wkly ; 148: w14580, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29376550

RESUMEN

Of the two million people estimated to be newly infected with human immunodeficiency virus (HIV) every year, 95% live in poorer regions of the world where effective HIV treatment is not universally available. Strategies to reduce the spread of HIV infection, which predominantly occurs via sexual contact, are urgently required. In the absence of an effective vaccine, a number of approaches to prevent HIV infection have been developed. These include using potent anti-HIV drugs prophylactically, either through systemic administration or topical application to the mucosal tissues that HIV initially encounters during sexual transmission. Genetic deficiency of the chemokine receptor CCR5 provides individuals with a remarkable degree of protection from HIV acquisition. This is because CCR5 is the major coreceptor used by HIV to infect new target cells. Since CCR5 deficiency does not appear to carry any health disadvantages, targeting the receptor is a promising strategy for both therapy and prevention of HIV. In this review we first describe the advantages and limitations of the currently available strategies for HIV prevention, then we focus on strategies targeting CCR5, covering the progress that has been made in developing different classes of CCR5 inhibitors for prophylaxis, and the perspectives for their future development as new weapons in the global fight against HIV/AIDS.


Asunto(s)
Infecciones por VIH/prevención & control , Receptores CCR5/genética , Terapia Genética/métodos , Humanos , Profilaxis Pre-Exposición
20.
Arterioscler Thromb Vasc Biol ; 37(12): 2342-2349, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29074586

RESUMEN

OBJECTIVE: We aimed to determine whether autoantibodies against apoA-1 (apolipoprotein A-1; anti-apoA-1 IgG) predict incident coronary artery disease (CAD), defined as adjudicated incident myocardial infarction, angina, percutaneous coronary revascularization, or bypass grafting, in the general population. We further investigated whether this association is modulated by a functional CD14 receptor single nucleotide polymorphism. APPROACH AND RESULTS: In a prospectively studied, population-based cohort of 5220 subjects (mean age 52.6±10.7 years, 47.4% males), followed over a median period of 5.6 years, subjects positive versus negative for anti-apoA-1 IgG presented a total CAD rate of 3.9% versus 2.8% (P=0.077) and a nonfatal CAD rate of 3.6% versus 2.3% (P=0.018), respectively. After multivariate adjustment for established cardiovascular risk factors, the hazard ratios of anti-apoA-1 IgG for total and nonfatal CAD were: hazard ratio=1.36 (95% confidence interval, 0.94-1.97; P=0.105) and hazard ratio=1.53 (95% confidence interval, 1.03-2.26; P=0.034), respectively. In subjects with available genetic data for the C260T rs2569190 single nucleotide polymorphism in the CD14 receptor gene (n=4247), we observed a significant interaction between anti-apoA-1 IgG and rs2569190 allele status with regards to CAD risk, with anti-apoA-1 IgG conferring the highest risk for total and nonfatal CAD in non-TT carriers, whereas being associated with the lowest risk for total and nonfatal CAD in TT homozygotes (P for interaction =0.011 and P for interaction =0.033, respectively). CONCLUSIONS: Anti-apoA-1 IgG are independent predictors of nonfatal incident CAD in the general population. The strength of this association is dependent on a functional polymorphism of the CD14 receptor gene, a finding suggesting a gene-autoantibody interaction for the development of CAD.


Asunto(s)
Apolipoproteína A-I/inmunología , Autoanticuerpos/sangre , Enfermedad de la Arteria Coronaria/genética , Inmunoglobulina G/sangre , Receptores de Lipopolisacáridos/genética , Polimorfismo de Nucleótido Simple , Adulto , Biomarcadores/sangre , Distribución de Chi-Cuadrado , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/epidemiología , Enfermedad de la Arteria Coronaria/inmunología , Femenino , Frecuencia de los Genes , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Heterocigoto , Homocigoto , Humanos , Incidencia , Estimación de Kaplan-Meier , Receptores de Lipopolisacáridos/inmunología , Masculino , Persona de Mediana Edad , Análisis Multivariante , Fenotipo , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Medición de Riesgo , Factores de Riesgo , Suiza/epidemiología , Factores de Tiempo
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