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1.
Invest New Drugs ; 42(1): 35-43, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38038862

RESUMEN

BACKGROUND: Indoleamine-2,3-dioxygenase (IDO) helps orchestrate immune suppression and checkpoint inhibitor resistance in hepatocellular carcinoma (HCC). BMS-986,205 is a novel oral drug that potently and selectively inhibits IDO. This Phase I/II study evaluated the safety and tolerability of BMS-986,205 in combination with nivolumab as first-line therapy in advanced HCC. METHODS: Adults with untreated, unresectable/metastatic HCC received BMS-986,205 at two dose levels (50-100 mg orally daily) in combination with fixed dose nivolumab (240mg/m2 IV on Day 1 of each 14-day cycle). The primary objective was to determine the safety and tolerability of this combination; secondary objectives were to obtain preliminary efficacy. RESULTS: Eight patients received a total of 91 treatment cycles in the dose escalation phase. All patients were Child Pugh A and 6 patients had underlying viral hepatitis. In the 6 evaluable patients, no dose-limiting toxicities (DLTs) were observed. The most common treatment-related adverse events (TRAEs) were aspartate transaminase (AST) and alanine transaminase (ALT) elevation (3 patients) and diarrhea, maculopapular rash and increased alkaline phosphatase (2 patients each). Grade 3 events were diarrhea and AST elevation (1 patient), and hyperglycemia and pancreatitis requiring treatment discontinuation (1 patient). No grade 4-5 events occurred. Partial response was observed in 1 patient (12.5%) and stable disease in 3 patients (37.5%), yielding a disease control rate of 50%. Median PFS was 8.5 weeks; median OS was not reached. CONCLUSION: Combination BMS-986,205 and nivolumab showed a manageable safety profile with durable benefit as first-line therapy in a meaningful subset of advanced HCC patients.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Adulto , Humanos , Alanina Transaminasa , Aspartato Aminotransferasas , Carcinoma Hepatocelular/tratamiento farmacológico , Diarrea , Neoplasias Hepáticas/tratamiento farmacológico , Nivolumab/efectos adversos , Nivolumab/uso terapéutico
3.
Cureus ; 15(9): e45934, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37885494

RESUMEN

This case report presents a rare occurrence of basal cell carcinoma (BCC) in the periungual region of the thumb. BCC is the most common type of skin cancer, typically found in sun-exposed areas. The discussion explores the underlying pathogenesis mechanisms, including the role of ultraviolet exposure, the absence of pilosebaceous units, and the involvement of the sonic hedgehog (SHH) pathway. Understanding the complexities of BCC in atypical locations is essential for effective prevention and treatment strategies.

5.
Nat Commun ; 14(1): 5332, 2023 09 02.
Artículo en Inglés | MEDLINE | ID: mdl-37658083

RESUMEN

Stereotactic ablative radiotherapy (SABR) is a standard-of-care for medically-inoperable-early-stage non-small cell lung cancer (NSCLC). One third of patients progress and chemotherapy is rarely used in this population. We questioned if addition of the immune-checkpoint-inhibitor (ICI) atezolizumab to standard-of-care SABR can improve outcomes. We initiated a multi-institutional single-arm phase I study (NCT02599454) enrolling twenty patients with the primary endpoint of maximum tolerated dose (MTD); secondary endpoints of safety and efficacy; and exploratory mechanistic correlatives. Treatment is well tolerated and full dose atezolizumab (1200 mg) is the MTD. Efficacy signals include early responses (after 2 cycles of ICI, before initiation of SABR) in 17% of patients. Biomarkers of functional adaptive immunity, including T cell activation in the tumor and response to ex-vivo stimulation by circulating T cells, are highly predictive of benefit. These results require validation and are being tested in a phase III randomized trial.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Radiocirugia , Carcinoma Pulmonar de Células Pequeñas , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/radioterapia
6.
Molecules ; 28(18)2023 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-37764242

RESUMEN

Twenty novel Mn, Fe, and Cu complexes of ethylene cross-bridged tetraazamacrocycles with potentially copolymerizable allyl and benzyl pendant arms were synthesized and characterized. Multiple X-ray crystal structures demonstrate the cis-folded pseudo-octahedral geometry forced by the rigidifying ethylene cross-bridge and show that two cis coordination cites are available for interaction with substrate and oxidant. The Cu complexes were used to determine kinetic stability under harsh acidic and high-temperature conditions, which revealed that the cyclam-based ligands provide superior stabilization with half-lives of many minutes or even hours in 5 M HCl at 50-90 °C. Cyclic voltammetry studies of the Fe and Mn complexes reveal reversible redox processes indicating stabilization of Fe2+/Fe3+ and Mn2+/Mn3+/Mn4+ oxidation states, indicating the likelihood of catalytic oxidation for these complexes. Finally, dye-bleaching experiments with methylene blue, methyl orange, and rhodamine B demonstrate efficient catalytic decolorization and allow selection of the most successful monomeric catalysts for copolymerization to produce future heterogeneous water purification materials.

7.
Behav Sci (Basel) ; 13(3)2023 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-36975251

RESUMEN

According to the epidemiological paradox, less acculturated Latina/o youth display fewer sexual risk behaviors. A systematic review was performed on psychosocial and cultural mechanisms potentially underlying the epidemiological paradox in sexual risk behaviors of U.S. Latina/o youth across acculturation measures (between January 2000 to October 2022). Thirty-five publications (n = 35) with forty-eight analyses of underlying mechanisms met the inclusion criteria. Thirty-one results from twenty-three publications found supporting evidence that one of the five factors was an underlying mechanism in the epidemiological paradox (n = 13 parenting practices, n = 4 peer influences, n = 4 familismo values, n = 4 religiosity, n = 6 traditional gender norms) as, generally protective, mediators or moderators in the link between acculturation and sexual risk behaviors. Studies varied in the sexual risk behavior examined and measurement of acculturation, but primarily employed cross-sectional designs and recruited samples through schools. Mechanisms that enhance close ties and unity of the family, such as those of familismo values and positive parenting, reduce the likelihood of sexual risk behaviors as Latina/o youth become more acculturated. Future directions are discussed which may provide guidance for risk prevention and intervention.

8.
Molecules ; 28(2)2023 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-36677952

RESUMEN

Tetraazamacrocycles, cyclic molecules with four nitrogen atoms, have long been known to produce highly stable transition metal complexes. Cross-bridging such molecules with two-carbon chains has been shown to enhance the stability of these complexes even further. This provides enough stability to use the resulting compounds in applications as diverse and demanding as aqueous, green oxidation catalysis all the way to drug molecules injected into humans. Although the stability of these compounds is believed to result from the increased rigidity and topological complexity imparted by the cross-bridge, there is insufficient experimental data to exclude other causes. In this study, standard organic and inorganic synthetic methods were used to produce unbridged dibenzyl tetraazamacrocycle complexes of Co, Ni, Cu, and Zn that are analogues of known cross-bridged tetraazamacrocycles and their transition metal complexes to allow direct comparison of molecules that are identical except for the cross-bridge. The syntheses of the known tetraazamacrocycles and the new transition metal complexes were successful with high yields and purity. Initial chemical characterization of the complexes was conducted by UV-Visible spectroscopy, while cyclic voltammetry showed more marked differences in electronic properties from bridged versions. Direct comparison studies of the unbridged and bridged compounds' kinetic stabilities, as demonstrated by decomposition using high acid concentration and elevated temperature, showed that the cyclen-based complex stability did not benefit from cross-bridging. This is likely due to poor complementarity with the Cu2+ ion while cyclam-based complexes benefited greatly. We conclude that ligand-metal complementarity must be maintained in order for the topological and rigidity constraints imparted by the cross-bridge to contribute significantly to complex robustness.


Asunto(s)
Complejos de Coordinación , Ciclamas , Elementos de Transición , Humanos , Complejos de Coordinación/química , Estructura Molecular , Rayos X , Elementos de Transición/química , Etilenos/química , Cristalografía por Rayos X
9.
Nat Med ; 28(9): 1813-1822, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36064599

RESUMEN

Amyotrophic lateral sclerosis (ALS) involves progressive motor neuron loss, leading to paralysis and death typically within 3-5 years of diagnosis. Dysfunctional astrocytes may contribute to disease and glial cell line-derived neurotrophic factor (GDNF) can be protective. Here we show that human neural progenitor cells transduced with GDNF (CNS10-NPC-GDNF) differentiated to astrocytes protected spinal motor neurons and were safe in animal models. CNS10-NPC-GDNF were transplanted unilaterally into the lumbar spinal cord of 18 ALS participants in a phase 1/2a study (NCT02943850). The primary endpoint of safety at 1 year was met, with no negative effect of the transplant on motor function in the treated leg compared with the untreated leg. Tissue analysis of 13 participants who died of disease progression showed graft survival and GDNF production. Benign neuromas near delivery sites were common incidental findings at post-mortem. This study shows that one administration of engineered neural progenitors can provide new support cells and GDNF delivery to the ALS patient spinal cord for up to 42 months post-transplantation.


Asunto(s)
Esclerosis Amiotrófica Lateral , Células-Madre Neurales , Esclerosis Amiotrófica Lateral/terapia , Animales , Modelos Animales de Enfermedad , Factor Neurotrófico Derivado de la Línea Celular Glial/genética , Humanos , Médula Espinal , Superóxido Dismutasa
10.
Eur J Ophthalmol ; 32(3): NP71-NP74, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-33567900

RESUMEN

INTRODUCTION: To report a case of a Hispanic girl with late-onset Retinoblastoma (Rb) who was misdiagnosed as a pars planitis prior to referral. Nearly 95% of all Rb cases are detected before age 5, and this patient was 8 years-old. METHODS: Case report of a late-onset Retinoblastoma with anterior chamber (AC) involvement plus the presence of an Ahmed valve. The patient had a history of a couple of months of topical therapy comprising medication for glaucoma, systemic steroids, and a filtration surgery (Ahmed valve), after that a biopsy was performed prior to referral. Upon arrival at our clinic, we performed an examination under anesthesia (EUA) and a B-scan ultrasound (US). RESULTS: Unilateral Retinoblastoma with an Ahmed valve in an AC filled with Rb seeds was diagnosed with the EUA and US in the left eye. An orbital exenteration with map biopsies of the left orbital cavity was performed with confirmation by histopathology of a poorly differentiated endophytic retinoblastoma with Bruch's membrane invasion. Follow-up sessions were then arranged as well as subsequent systemic chemotherapy cycles. CONCLUSION: Given the rare incidence of retinoblastoma in children older than 5 years old, it can be easily mistaken for other differential diagnoses and treated with filtration surgeries that could put the patient's life at risk. In this report, late-onset Rb diagnosis is highlighted as a differential diagnosis in children and adults with atypical uveitis, which required a multidisciplinary approach.


Asunto(s)
Pars Planitis , Neoplasias de la Retina , Retinoblastoma , Uveítis Intermedia , Cámara Anterior/patología , Niño , Preescolar , Femenino , Hispánicos o Latinos , Humanos , Neoplasias de la Retina/diagnóstico , Neoplasias de la Retina/patología , Retinoblastoma/diagnóstico , Retinoblastoma/patología , Estudios Retrospectivos
11.
Molecules ; 28(1)2022 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-36615426

RESUMEN

Ethylene cross-bridged tetraazamacrocycles are known to produce kinetically stable transition metal complexes that can act as robust oxidation catalysts under harsh aqueous conditions. We have synthesized ligand analogs with single acetate pendant arms that act as pentadentate ligands to Mn, Fe, Co, Ni, Cu, and Zn. These complexes have been synthesized and characterized, including the structural characterization of four Co and Cu complexes. Cyclic voltammetry demonstrates that multiple oxidation states are stabilized by these rigid, bicyclic ligands. Yet, redox potentials of the metal complexes are modified compared to the "parent" ligands due to the pendant acetate arm. Similarly, gains in kinetic stability under harsh acidic conditions, compared to parent complexes without the pendant acetate arm, were demonstrated by a half-life seven times longer for the cyclam copper complex. Due to the reversible, high oxidation states available for the Mn and Fe complexes, the Mn and Fe complexes were examined as catalysts for the bleaching of three commonly used pollutant model dyes (methylene blue, methyl orange, and Rhodamine B) in water with hydrogen peroxide as oxidant. The efficient bleaching of these dyes was observed.


Asunto(s)
Complejos de Coordinación , Ciclamas , Elementos de Transición , Complejos de Coordinación/química , Cristalografía por Rayos X , Etilenos/química , Ligandos , Oxidación-Reducción
12.
Biotechnol Rep (Amst) ; 26: e00456, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32373484

RESUMEN

Technological advances allowed the development of high-throughput instruments such as IntelliCyt iQue Screener PLUS®. Here, we took advantage of this technology to transfer a previously validated cytotoxicity assay. The evaluated parameters were cell permeability, caspase activation and phosphatidyl serine exposure. The assay was accurate (r2 = 0.90), precise (%CV ≤ 18.90) and specific. These results showed that this technology is suitable to be used in control quality environments. In addition, the automation provided a faster acquisition and analysis of data with precise and accurate results. This application could be implemented to evaluate another in vitro mechanism of action of different biotherapeutics.

13.
Biotechnol Rep (Amst) ; 22: e00331, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31061815

RESUMEN

The biotherapeutic type I interferons (IFN-I) are indicated to treat several diseases. These products are regulated to guarantee safety and efficacy through critical quality attributes. For this purpose, the development of robust assays is required, followed by its validation to demonstrate their suitability for its intended purpose. Despite there are some commercial kits to evaluate IFN-I signaling, these are focused on measuring in vitro biological response instead of their validation, which is a pharmaceutical industry requirement. The aim of this work was to validate the HEK-Blue IFN-α/ß system evaluating the biological activity of IFN-α/ß under good laboratory practices, according to international standards. Our results demonstrated that HEK-Blue IFN-α/ß system comply with accuracy (r2>0.95) precision (CV < 20%) and specificity for both IFN-α/ß; confirming that this assay is robust for this biotherapeutics' evaluation. Thereby, this bioassay could be implemented as a complementary method to the classical anti-proliferative and anti-viral assays under quality control environments.

14.
J Food Sci ; 84(3): 430-439, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30768685

RESUMEN

Collagen hydrolysates are dietary supplements used for nutritional and medical purposes. They are complex mixtures of low-molecular-weight peptides obtained from the enzymatic hydrolysis of collagen, which provide intrinsic batch-to-batch heterogeneity. In consequence, the quality of these products, which is related to the reproducibility of their mass distribution pattern, should be addressed. Here, we propose an analytical approach to determine the peptide pattern as a quality attribute of Colagenart®, a product containing collagen hydrolysate. In addition, we evaluated the safety by measuring the viability of two cell lines exposed to the product. The consistency of peptide distribution was determined using Size Exclusion Chromatography (SEC), Mass Spectrometry coupled to a reversed phase UPLC system (MS-RP-UPLC), and Shaped-pulse off-resonance water-presaturation proton nuclear magnetic resonance spectrometry [1 Hwater_presat NMR]. The mass distribution pattern determined by SEC was in a range from 1.35 to 17 kDa, and from 2 to 14 kDa by MS-RP-UPLC. [1 Hwater_presat NMR] showed the detailed spin-systems of the collagen hydrolysates components by global assignment of backbone Hα and NH, as well as side-chain proton resonances. Additionally, short-range intraresidue connectivity pathways of identified spin-regions were obtained by a 2D homonuclear shift correlation Shaped-pulse solvent suppression COSY scheme. Safety analysis of Colagenart® was evaluated in CaCo-2 and HepG2 cells at 2.5 and 25 µg/mL and no negative effects were observed. The results demonstrated batch-to-batch reproducibility, which evinces the utility of this approach to establish the consistency of the quality attributes of collagen hydrolysates. PRACTICAL APPLICATION: We propose state-of-the art analytical methodologies (SEC, MS, and NMR) to evaluate peptide profile and composition of collagen hydrolysates as quality attributes. These methodologies are suitable to be implemented for quality control purposes.


Asunto(s)
Colágeno/química , Péptidos/química , Células CACO-2 , Cromatografía en Gel , Colágeno/metabolismo , Inocuidad de los Alimentos , Humanos , Hidrólisis , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Peso Molecular , Péptidos/aislamiento & purificación , Péptidos/metabolismo , Hidrolisados de Proteína/química , Hidrolisados de Proteína/metabolismo , Control de Calidad
15.
J Immunol Methods ; 464: 87-94, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30395815

RESUMEN

The development of biotherapeutics requires continuous improvement in analytical methodologies for the assessment of their quality attributes. A subset of biotherapeutics is designed to interact with specific antigens that are exposed on the membranes of target cells or circulating in a soluble form, and effector functions are achieved via recognition of their Fc region by effector cells that induce mechanisms such as antibody-dependent cell-mediated cytotoxicity (ADCC). Thus, ADCC induction is a critical quality attribute (CQA) that must be evaluated to ensure biotherapeutic efficacy. Induction of ADCC can be evaluated by employing effector cells from different sources, such as peripheral blood mononuclear cells (PBMC) and genetically modified cell lines (e.g., transfected NKs or Jurkat cells), and different approaches can be used for detection and results interpretation depending on the type of effector cells used. In this regard, validation of the assays is relevant to ensure the reliability of the results according to the intended purpose. Herein, we show the standardization and validation of ADCC assays to test the potency of three biotherapeutic proteins using primary NK cells obtained from fresh blood as effector cells and detecting cell death by flow cytometry. The advantage of using primary NKs instead of modified cells is that the response is closer to that occurring in vivo since cytotoxicity is evaluated in a direct manner. Our results indicate that in all cases, the assays exhibited a characteristic sigmoidal dose/response curve complying with accurate, precise and specific parameters. Thereby, the validated ADCC assay is an appropriate alternative to evaluate the biological activities of these type of biotherapeutics.


Asunto(s)
Adalimumab/farmacología , Citotoxicidad Celular Dependiente de Anticuerpos/efectos de los fármacos , Antineoplásicos Inmunológicos/farmacología , Linfoma de Burkitt/tratamiento farmacológico , Separación Celular/métodos , Etanercept/farmacología , Citometría de Flujo , Células Asesinas Naturales/efectos de los fármacos , Rituximab/farmacología , Animales , Linfoma de Burkitt/inmunología , Linfoma de Burkitt/patología , Células CHO , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Cricetulus , Relación Dosis-Respuesta a Droga , Humanos , Células Asesinas Naturales/inmunología , Cultivo Primario de Células , Reproducibilidad de los Resultados
16.
Med. interna Méx ; 34(6): 1000-1006, nov.-dic. 2018. tab, graf
Artículo en Español | LILACS | ID: biblio-990171

RESUMEN

Resumen Se comunica el caso de un paciente de 55 años de edad que inició con fiebre como síntoma principal de su padecimiento. Después de un protocolo de estudio sistematizado y orientado se llegó al diagnóstico de fiebre de origen desconocido como síndrome, cuyo diagnóstico etiológico fue mielofibrosis primaria, enfermedad hematológica poco frecuente que se distingue por fibrosis de la médula ósea, esplenomegalia y anemia. Se revisa el abordaje de la fiebre y sus etapas de estudio siguiendo las recomendaciones actuales, técnicas y científicas, pero adaptadas a nuestro medio y recursos.


Abstract This paper reports the case of a 55 year-old man who presented with fever as a primary symptom of his condition. A systematic protocol oriented study led to the diagnosis of fever of unknown origin as a syndrome whose etiologic diagnosis was primary myelofibrosis; rare hematologic disease characterized by fibrosis of the bone marrow, anemia and splenomegaly. A review of the approach of fever and stages of study is done according to current recommendations, technical and scientific, but adapted to our environment and resources.

17.
Med. interna Méx ; 34(4): 638-644, jul.-ago. 2018. graf
Artículo en Español | LILACS | ID: biblio-984723

RESUMEN

Resumen La púrpura de Henoch-Schönlein como vasculitis paraneoplásica de tumores sólidos se encuentra en 9 a 11% de los casos reportados en adultos con carcinoma de estómago, mama, pulmón, próstata o riñón; es poco frecuente como paraneoplásico de mieloma múltiple. Se comunica el caso de una paciente que padeció púrpura de Henoch-Schönlein como manifestación inicial de mieloma múltiple.


Abstract Henoch-Schonlein purpura as paraneoplasic vasculitis of solid tumors is found in 9-11% of cases reported in adults with stomach, breast, lung, prostate and kidney carcinomas; it is little frequent as paraneoplastic of multiple myeloma. This paper reports the case of a patient that suffered from Henoch-Schonlein purpura as initial manifestation of multiple myeloma.

18.
Tissue Eng Part A ; 24(21-22): 1641-1651, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29766758

RESUMEN

Recombinant human bone morphogenic protein-2 (BMP-2)-loaded absorbable collagen sponges (ACS) have been successfully used to enhance bone formation and to induce spinal fusion in humans. However, side effects, such as soft tissue edema and inflammation, have been reported. NEMO binding domain peptide (NBD) inhibits activation of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), a central regulator of immune response. In this study, we investigated NBD's potential to reduce BMP-2-induced soft tissue inflammation without affecting BMP-2-mediated spinal fusion in rat. For evaluation of soft tissue inflammation, ACS containing BMP-2, BMP-2+NBD, NBD, or ACS only were implanted into intramuscular paraspinal sites of 32 rats. At day 2 postsurgery, edema formation at the implant sites was assessed using magnetic resonance imaging. T2-weighted relaxation time (T2-RT) values were increased in the BMP-2 group compared with BMP-2+NBD, NBD, and ACS groups. No difference in T2-RT values was detected between BMP-2+NBD versus NBD and ACS controls. Postsacrifice, histological analysis of the implant-surrounding zones showed increased mononuclear cell infiltration in the BMP-2 group compared with BMP-2+NBD and controls. The presence of BMP-2 increased relative NF-κB binding and gene expression of inflammatory markers, interleukin (IL)1ß, IL6, IL18, and chemokine ligand (CCL)2 and CCL3 compared with controls. In the BMP-2+NBD group, cytokine expression was blocked. No differences were found between BMP-2+NBD and control groups. For evaluation of spinal fusion, posterolateral intertransverse lumbar fusion procedures were performed on 16 rats. ACS were loaded with BMP-2 or BMP-2+NBD. After sacrifice at week 12, microcomputed tomographic assessment of the fusion site detected a higher bone volume and reduced trabecular spacing in the BMP-2+NBD group compared with BMP-2. Histological analysis did not show any differences in newly formed bone microarchitecture. In summary, addition of NBD to BMP-2-loaded ACS reduces BMP-2-induced soft tissue edema formation and mononuclear cell infiltration, diminishes NF-κB binding, and thus blocks transcription of NF-κB-regulated cytokines in rat. Furthermore, NBD stimulates bone formation in BMP-2-mediated spinal fusion, possibly through crosstalk of the NF-κB pathway with other pathways. The results of this study might provide the basis to develop new therapeutic bone grafting approaches with combinatory administration of BMP-2 and NBD for spinal fusion.


Asunto(s)
Proteína Morfogenética Ósea 2/farmacología , Edema/prevención & control , Péptidos/farmacología , Fusión Vertebral , Animales , Edema/metabolismo , Edema/patología , Humanos , Masculino , Ratas , Ratas Sprague-Dawley , Proteínas Recombinantes/efectos adversos , Proteínas Recombinantes/farmacología
19.
Stem Cell Reports ; 10(6): 1696-1704, 2018 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-29706501

RESUMEN

Trophic factor delivery to the brain using stem cell-derived neural progenitors is a powerful way to bypass the blood-brain barrier. Protection of diseased neurons using this technology is a promising therapy for neurodegenerative diseases. Glial cell line-derived neurotrophic factor (GDNF) has provided benefits to Parkinsonian patients and is being used in a clinical trial for amyotrophic lateral sclerosis. However, chronic trophic factor delivery prohibits dose adjustment or cessation if side effects develop. To address this, we engineered a doxycycline-regulated vector, allowing inducible and reversible expression of a therapeutic molecule. Human induced pluripotent stem cell (iPSC)-derived neural progenitors were stably transfected with the vector and transplanted into the adult mouse brain. Doxycycline can penetrate the graft, with addition and withdrawal providing inducible and reversible GDNF expression in vivo, over multiple cycles. Our findings provide proof of concept for combining gene and stem cell therapy for effective modulation of ectopic protein expression in transplanted cells.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica , Factor Neurotrófico Derivado de la Línea Celular Glial/genética , Células Madre Pluripotentes Inducidas/citología , Células Madre Pluripotentes Inducidas/metabolismo , Células-Madre Neurales/citología , Células-Madre Neurales/metabolismo , Trasplante de Células Madre , Tratamiento Basado en Trasplante de Células y Tejidos , Expresión Génica , Genes Reporteros , Terapia Genética , Vectores Genéticos/genética , Factor Neurotrófico Derivado de la Línea Celular Glial/metabolismo , Humanos , Plantas Modificadas Genéticamente , Trasplante de Células Madre/métodos , Transducción Genética , Transgenes
20.
Sci Rep ; 7(1): 12125, 2017 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-28935954

RESUMEN

Glatiramer Acetate (GA) is an immunomodulatory medicine approved for the treatment of multiple sclerosis, whose mechanisms of action are yet to be fully elucidated. GA is comprised of a complex mixture of polypeptides with different amino acid sequences and structures. The lack of sensible information about physicochemical characteristics of GA has contributed to its comprehensiveness complexity. Consequently, an unambiguous determination of distinctive attributes that define GA is of highest relevance towards dissecting its identity. Herein we conducted a study of characteristic GA heterogeneities throughout its manufacturing process (process signatures), revealing a strong impact of critical process parameters (CPPs) on the reactivity of amino acid precursors; reaction initiation and polymerization velocities; and peptide solubility, susceptibility to hydrolysis, and size-exclusion properties. Further, distinctive GA heterogeneities were correlated to defined immunological and toxicological profiles, revealing that GA possesses a unique repertoire of active constituents (epitopes) responsible of its immunological responses, whose modification lead to altered profiles. This novel approach established CPPs influence on intact GA peptide mixture, whose physicochemical identity cannot longer rely on reduced properties (based on complete or partial GA degradation), providing advanced knowledge on GA structural and functional relationships to ensure a consistent manufacturing of safe and effective products.

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