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1.
Cell ; 175(1): 171-185.e25, 2018 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-30146162

RESUMEN

CKIα ablation induces p53 activation, and CKIα degradation underlies the therapeutic effect of lenalidomide in a pre-leukemia syndrome. Here we describe the development of CKIα inhibitors, which co-target the transcriptional kinases CDK7 and CDK9, thereby augmenting CKIα-induced p53 activation and its anti-leukemic activity. Oncogene-driving super-enhancers (SEs) are highly sensitive to CDK7/9 inhibition. We identified multiple newly gained SEs in primary mouse acute myeloid leukemia (AML) cells and demonstrate that the inhibitors abolish many SEs and preferentially suppress the transcription elongation of SE-driven oncogenes. We show that blocking CKIα together with CDK7 and/or CDK9 synergistically stabilize p53, deprive leukemia cells of survival and proliferation-maintaining SE-driven oncogenes, and induce apoptosis. Leukemia progenitors are selectively eliminated by the inhibitors, explaining their therapeutic efficacy with preserved hematopoiesis and leukemia cure potential; they eradicate leukemia in MLL-AF9 and Tet2-/-;Flt3ITD AML mouse models and in several patient-derived AML xenograft models, supporting their potential efficacy in curing human leukemia.


Asunto(s)
Caseína Quinasa Ialfa/antagonistas & inhibidores , Leucemia Mieloide Aguda/tratamiento farmacológico , Animales , Apoptosis/efectos de los fármacos , Caseína Quinasa Ialfa/fisiología , Proliferación Celular/efectos de los fármacos , Quinasa 9 Dependiente de la Ciclina/antagonistas & inhibidores , Quinasa 9 Dependiente de la Ciclina/fisiología , Quinasas Ciclina-Dependientes/antagonistas & inhibidores , Quinasas Ciclina-Dependientes/fisiología , Proteínas de Unión al ADN , Modelos Animales de Enfermedad , Elementos de Facilitación Genéticos/genética , Hematopoyesis , Humanos , Ratones , Ratones Endogámicos C57BL , Proteínas de Fusión Oncogénica/metabolismo , Proteínas Serina-Treonina Quinasas , Proteínas Proto-Oncogénicas , Proteína p53 Supresora de Tumor/fisiología , Ensayos Antitumor por Modelo de Xenoinjerto
2.
Immunity ; 53(4): 775-792.e9, 2020 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-33002412

RESUMEN

Innate lymphoid cells (ILCs) are generated early during ontogeny and persist predominantly as tissue-resident cells. Here, we examined how ILCs are maintained and renewed within tissues. We generated a single cell atlas of lung ILC2s and found that Il18r1+ ILCs comprise circulating and tissue-resident ILC progenitors (ILCP) and effector-cells with heterogeneous expression of the transcription factors Tcf7 and Zbtb16, and CD103. Our analyses revealed a continuous differentiation trajectory from Il18r1+ ST2- ILCPs to Il18r- ST2+ ILC2s, which was experimentally validated. Upon helminth infection, recruited and BM-derived cells generated the entire spectrum of ILC2s in parabiotic and shield chimeric mice, consistent with their potential role in the renewal of tissue ILC2s. Our findings identify local ILCPs and reveal ILCP in situ differentiation and tissue adaptation as a mechanism of ILC maintenance and phenotypic diversification. Local niches, rather than progenitor origin, or the developmental window during ontogeny, may dominantly imprint ILC phenotypes in adult tissues.


Asunto(s)
Inmunidad Innata/inmunología , Linfocitos/inmunología , Células Progenitoras Linfoides/inmunología , Animales , Diferenciación Celular/inmunología , Células Cultivadas , Femenino , Humanos , Subunidad alfa del Receptor de Interleucina-18/inmunología , Pulmón/inmunología , Ratones , Ratones Endogámicos C57BL , Proteína de la Leucemia Promielocítica con Dedos de Zinc/inmunología , Transducción de Señal/inmunología , Análisis de la Célula Individual/métodos , Factor 1 de Transcripción de Linfocitos T/inmunología , Factores de Transcripción/inmunología
3.
Br J Haematol ; 203(5): 840-851, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37614192

RESUMEN

Comorbidity assessment before allogeneic haematopoietic cell transplantation (allo-HCT) is essential for estimating non-relapse mortality (NRM) risk. We previously developed the Simplified Comorbidity Index (SCI), which captures a small number of 'high-yield' comorbidities and older age. The SCI was predictive of NRM in myeloablative CD34-selected allo-HCT. Here, we evaluated the SCI in a single-centre cohort of 327 patients receiving reduced-intensity conditioning followed by unmanipulated allografts from HLA-matched donors. Among the SCI factors, age above 60, mild renal impairment, moderate pulmonary disease and cardiac disease were most frequent. SCI scores ranged from 0 to 8, with 39%, 20%, 20% and 21% having scores of 0-1, 2, 3 and ≥4 respectively. Corresponding cumulative incidences of 3-year NRM were 11%, 16%, 22% and 27%; p = 0.03. In multivariable models, higher SCI scores were associated with incremental risks of all-cause mortality and NRM. The SCI had an area under the receiver operating characteristic curve of 65.9%, 64.1% and 62.9% for predicting 1-, 2- and 3-year NRM versus 58.4%, 60.4% and 59.3% with the haematopoietic cell transplantation comorbidity index. These results demonstrate for the first time that the SCI is predictive of NRM in patients receiving allo-HCT from HLA-matched donors after reduced-intensity conditioning.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Donantes de Tejidos , Humanos , Comorbilidad , Trasplante de Células Madre Hematopoyéticas/métodos , Recurrencia , Estudios Retrospectivos , Acondicionamiento Pretrasplante/métodos , Trasplante Homólogo/métodos , Mortalidad
4.
Haematologica ; 106(7): 1846-1856, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-32467141

RESUMEN

Anti-RhD antibodies are widely used in clinical practice to prevent immunization against RhD, principally in hemolytic disease of the fetus and newborn. Intriguingly, this disease is induced by production of the very same antibodies when an RhD negative woman is pregnant with an RhD positive fetus. Despite over five decades of use, the mechanism of this treatment is, surprisingly, still unclear. Here we show that anti-RhD antibodies induce human natural killer (NK) cell degranulation. Mechanistically, we demonstrate that NK cell degranulation is mediated by binding of the Fc segment of anti-RhD antibodies to CD16, the main Fcγ receptor expressed on NK cells. We found that this CD16 activation is dependent upon glycosylation of the anti-RhD antibodies. Furthermore, we show that anti-RhD antibodies induce NK cell degranulation in vivo in patients who receive this treatment prophylactically. Finally, we demonstrate that the anti-RhD drug KamRho enhances the killing of dendritic cells. We suggest that this killing leads to reduced activation of adaptive immunity and may therefore affect the production of anti-RhD antibodies.


Asunto(s)
Células Asesinas Naturales , Receptores de IgG , Femenino , Feto/metabolismo , Glicosilación , Humanos , Recién Nacido , Activación de Linfocitos , Embarazo , Receptores de IgG/metabolismo
5.
Br J Haematol ; 187(1): 25-38, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31418827

RESUMEN

Regulatory T cells (Treg cells) represent a CD4+ T-cell lineage that plays a critical role in restraining immune responses to self and foreign antigens and associated inflammation. Due to the suppressive function of Treg cells, inhibition or ablation of these cells can be used to boost the immunity against malignant cells. On the other hand, augmenting the activity of Treg cells can be employed for the treatment of inflammatory or autoimmune diseases and allogeneic conflicts associated with transplantation. Graft-versus-host disease (GvHD) is a leading cause of morbidity and mortality after haematopoietic stem cell transplantation (HSCT). In this review, we describe basic biological properties of Treg cells and their role in GvHD. We focus on the application of adoptive transfer of Treg cells and the therapeutic modulation of their activity for the prevention and treatment of GvHD in pre-clinical models and in clinical settings. We also discuss the main obstacles to applying Treg cell-based therapies for GvHD in clinical practice.


Asunto(s)
Enfermedad Injerto contra Huésped/terapia , Transfusión de Linfocitos/métodos , Linfocitos T Reguladores/trasplante , Animales , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/terapia , Modelos Animales de Enfermedad , Enfermedad Injerto contra Huésped/inmunología , Humanos , Inmunoterapia Adoptiva/métodos , Activación de Linfocitos/inmunología , Linfocitos T Reguladores/inmunología
6.
J Foot Ankle Surg ; 56(4): 851-853, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28633790

RESUMEN

Osteomyelitis due to Ochrobactrum anthropi, a new genus Ochrobacterum widely distributed in the environment and occasionally associated with human infection, has been described in only a few case reports. We present a report of an unusual case of osteomyelitis caused by O. anthropi that was identified 9 years after a nail puncture to the lateral cuneiform bone. The patient was an 18-year-old male with a painful foot lesion that had originally been misdiagnosed as an osteolytic tumor. He underwent surgery and 2 firm pieces of rubber measuring 7 and 10 mm were removed from the lower portion of the lateral cuneiform bone, which appeared to be affected by an infection. After surgical debridement, O. anthropi was isolated from the bone cultures. The patient was successfully treated with a 6-week course of oral ciprofloxacin and clindamycin. At 1 year after the corrected diagnosis and appropriate treatment, he was symptom free and had resumed regular activities and an athletic lifestyle.


Asunto(s)
Infecciones por Bacterias Gramnegativas/microbiología , Ochrobactrum anthropi/aislamiento & purificación , Osteomielitis/diagnóstico , Osteomielitis/microbiología , Heridas Penetrantes/microbiología , Adolescente , Antibacterianos/uso terapéutico , Neoplasias Óseas/diagnóstico , Ciprofloxacina/uso terapéutico , Clindamicina/uso terapéutico , Desbridamiento , Diagnóstico Diferencial , Infecciones por Bacterias Gramnegativas/complicaciones , Infecciones por Bacterias Gramnegativas/diagnóstico , Infecciones por Bacterias Gramnegativas/terapia , Humanos , Masculino , Osteomielitis/diagnóstico por imagen , Osteomielitis/terapia , Heridas Penetrantes/terapia
7.
Blood ; 123(10): 1535-43, 2014 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-24449212

RESUMEN

PML-RARA and AML1-ETO are important oncogenic fusion proteins that play a central role in transformation to acute myeloid leukemia (AML). Whether these fusion proteins render the tumor cells with immune evasion properties is unknown. Here we show that both oncogenic proteins specifically downregulate the expression of CD48, a ligand of the natural killer (NK) cell activating receptor 2B4, thereby leading to decreased killing by NK cells. We demonstrate that this process is histone deacetylase (HDAC)-dependent, that it is mediated through the downregulation of CD48 messenger RNA, and that treatment with HDAC inhibitors (HDACi) restores the expression of CD48. Furthermore, by using chromatin immunoprecepitation (ChIP) experiments, we show that AML1-ETO directly interacts with CD48. Finally, we show that AML patients who are carrying these specific translocations have low expression of CD48.


Asunto(s)
Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/inmunología , Proteínas de Fusión Oncogénica/genética , Proteínas de Fusión Oncogénica/inmunología , Escape del Tumor/genética , Escape del Tumor/inmunología , Antígenos CD/química , Antígenos CD/genética , Antígenos CD/metabolismo , Secuencia de Bases , Antígeno CD48 , Línea Celular Tumoral , Subunidad alfa 2 del Factor de Unión al Sitio Principal/genética , Subunidad alfa 2 del Factor de Unión al Sitio Principal/inmunología , Citotoxicidad Inmunológica , Expresión Génica , Regulación de la Expresión Génica , Histona Desacetilasas/metabolismo , Humanos , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/metabolismo , Leucemia Mieloide Aguda/metabolismo , Datos de Secuencia Molecular , Proteínas de Fusión Oncogénica/metabolismo , Proteína 1 Compañera de Translocación de RUNX1
8.
PLoS Pathog ; 9(8): e1003568, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23966863

RESUMEN

Natural killer (NK) cells are innate immune cells able to rapidly kill virus-infected and tumor cells. Two NK cell populations are found in the blood; the majority (90%) expresses the CD16 receptor and also express the CD56 protein in intermediate levels (CD56(Dim) CD16(Pos)) while the remaining 10% are CD16 negative and express CD56 in high levels (CD56(Bright) CD16(Neg)). NK cells also reside in some tissues and traffic to various infected organs through the usage of different chemokines and chemokine receptors. Kaposi's sarcoma-associated herpesvirus (KSHV) is a human virus that has developed numerous sophisticated and versatile strategies to escape the attack of immune cells such as NK cells. Here, we investigate whether the KSHV derived cytokine (vIL-6) and chemokines (vMIP-I, vMIP-II, vMIP-III) affect NK cell activity. Using transwell migration assays, KSHV infected cells, as well as fusion and recombinant proteins, we show that out of the four cytokine/chemokines encoded by KSHV, vMIP-II is the only one that binds to the majority of NK cells, affecting their migration. We demonstrate that vMIP-II binds to two different receptors, CX3CR1 and CCR5, expressed by naïve CD56(Dim) CD16(Pos) NK cells and activated NK cells, respectively. Furthermore, we show that the binding of vMIP-II to CX3CR1 and CCR5 blocks the binding of the natural ligands of these receptors, Fractalkine (Fck) and RANTES, respectively. Finally, we show that vMIP-II inhibits the migration of naïve and activated NK cells towards Fck and RANTES. Thus, we present here a novel mechanism in which KSHV uses a unique protein that antagonizes the activity of two distinct chemokine receptors to inhibit the migration of naïve and activated NK cells.


Asunto(s)
Fármacos Anti-VIH/farmacología , Antagonistas de los Receptores CCR5 , Movimiento Celular/efectos de los fármacos , Quimiocinas/farmacología , Herpesvirus Humano 8/química , Células Asesinas Naturales/efectos de los fármacos , Receptores de Quimiocina/antagonistas & inhibidores , Receptor 1 de Quimiocinas CX3C , Células Cultivadas , Quimiocina CCL5/metabolismo , Quimiocina CX3CL1/metabolismo , Citocinas/genética , Citocinas/metabolismo , Humanos , Immunoblotting , Interleucina-6 , Células Asesinas Naturales/citología , Células Asesinas Naturales/metabolismo , Reacción en Cadena de la Polimerasa , Receptores CCR5/genética , Receptores CCR5/metabolismo , Receptores de Quimiocina/genética , Receptores de Quimiocina/metabolismo
9.
Emerg Med J ; 32(2): 149-52, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24123168

RESUMEN

INTRODUCTION: Patients' gender remains a contributor for bias in pain management. Implementation of standardised analgesic protocols has been shown to minimise bias in analgesic care. The purpose of this study was to assess whether gender-related bias in pain management exists in our emergency department (ED) setting, where a standardised pain management protocol based on patients' subjective pain rating is routinely used. METHODS: Pain management measures (ie, analgesia administration, waiting time for analgesia, pain relief and patients' satisfaction) were prospectively assessed in 328 patients (150 women and 178 men, average age 36±18 years) who were treated in our ED for acute musculoskeletal pain. RESULTS: Patients' subjective pain rating on arrival were similar for men and women (59±24 mm vs 61±26 mm, respectively; p=0.47). Interestingly, physicians using the same scale assessed the women's pain level to be higher than that of men (75±25 mm vs 63±22 mm, respectively; p<0.001) and higher than that of women's subjective pain rating (75±25 mm vs 61±26 mm respectively; p<0.001). Nevertheless, the rates of analgesia administration, waiting time for analgesia, pain relief and patient satisfaction were similar for both genders. Physicians' own gender did not affect analgesic care. CONCLUSIONS: Our findings suggest that a standardised pain management protocol based on patients' subjective pain rating may reduce gender-related bias in acute musculoskeletal pain management.


Asunto(s)
Analgésicos/uso terapéutico , Servicio de Urgencia en Hospital , Dolor Musculoesquelético/tratamiento farmacológico , Manejo del Dolor/estadística & datos numéricos , Sexismo , Adulto , Anciano , Analgesia/métodos , Servicio de Urgencia en Hospital/estadística & datos numéricos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor/métodos , Satisfacción del Paciente , Estudios Prospectivos , Factores Sexuales , Factores de Tiempo , Adulto Joven
10.
Blood Adv ; 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38768428

RESUMEN

HBI0101 is an academic chimeric antigen receptor T (CART) targeted to BCMA for the treatment of relapsed and refractory multiple myeloma (RRMM) and light chain amyloidosis. Herein, we present the Phase Ib/II results of fifty heavily pre-treated RRMM patients dosed with 800x106 CART cells (NCT04720313). Inclusion criteria were relatively permissive (i.e., performance status and baseline organ function) and consequently, about half of the enrolled patients would have been ineligible for pivotal clinical trials. The median time elapsed from patient enrolment until CART delivery was 25 days (range, 14-65). HBI0101-related toxicities included grade 1-3 cytokine-release syndrome, grade 3-4 hematologic toxicities and grade 1-2 immune effector cell-associated neurotoxicity syndrome. Responses were achieved in 90% of the patients, 56% achieved stringent and complete response (sCR/CR), and 70% reached a minimal residual disease negativity. Within a median follow-up of 12.3 months, the median progression-free survival (PFS) was 11.0 months; (95% CI, 6.2-14.6), and the overall survival was not reached (95% CI, 13.3-not reached). Multivariable analysis on patient/disease and CART cell-related characteristics revealed that high-risk cytogenetic, extramedullary disease, and increased number of effector-memory T-cells in CART products were independently associated with inferior PFS. In conclusion, comprehensive analyses of the parameters affecting the response to CART therapy are essential for improving patients' outcome.

11.
J Allergy Clin Immunol Glob ; 2(3): 100128, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37779518

RESUMEN

Background: Pruritus can be an intolerable symptom in patients with cancer. Type 2 inflammation, and specifically, the cytokines IL-4, IL-13, and IL-31, play major roles in the itching process. Dupilumab is an antibody against IL-4Rα, which is a common IL-4 and IL-13 receptor subunit. Blocking IL-4 and IL-13 activity reduces the synthesis of IL-31, the "itch cytokine," and receptors for these 3 cytokines are expressed on itch nerves. Dupilumab is approved for treating moderate-to-severe atopic dermatitis, of which itching is a significant symptom. Objective: The objective of this case study was to present the initial evidence of the safety and efficacy of dupilumab as a treatment for intractable malignancy-associated pruritus in 3 patients, thereby providing a basis for further investigation in a larger cohort. Methods: As a proof of concept, we used dupilumab in our center to treat 3 patients with intractable malignancy-associated pruritus. The first patient was a 73-year-old male with a history of prostate cancer, the second patient was a 75-year-old female with cutaneous T-cell lymphoma, and the third patient was a 32-year-old male with metastatic melanoma. All 3 patients experienced debilitating itching, which started at some stage after the malignancy had been diagnosed. Moreover, none of the 3 patients showed clinical evidence of atopic dermatitis or other causes of itching (eg, uremia or liver failure), and none of the 3 patients responded to conventional treatments for pruritus. Results: Biweekly treatment with dupilumab led to an immediate improvement in itching, which subsided entirely after a few doses without any significant adverse effects. Conclusion: We propose that dupilumab is a safe and effective treatment for intractable malignancy-associated pruritus, and we are currently testing it in a large cohort.

12.
RNA Biol ; 9(6): 792-8, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22617882

RESUMEN

Natural killer (NK) cells play an important role in the direct killing of cancerous and virus-infected cells. One of the important activating receptors which mediates this killing is NKG2D. This receptor recognizes various stress-induced ligands including the major histocompatibility complex class I-related chain A and B (MICA and MICB respectively). The mechanisms controlling the expression of the NKG2D ligands are not completely understood, yet various studies have demonstrated that the expression of the NKG2D ligands is manipulated by viruses and by tumor cells in order to escape the NKG2D detection. Cumulative data have emphasized that various microRNAs (miRNAs) of both human and viral origin control the expression of NKG2D ligands, particularly MICB. Herein we review recent findings regarding the miRNA regulation of the NKG2D ligands. We propose that these miRNAs generate a complex network of interactions that control the expression of the NKG2D ligands under normal conditions and during disease development.


Asunto(s)
Antígenos de Histocompatibilidad Clase I/genética , Péptidos y Proteínas de Señalización Intercelular/genética , MicroARNs/fisiología , Interferencia de ARN , Secuencia de Bases , Proteínas Ligadas a GPI/genética , Proteínas Ligadas a GPI/metabolismo , Redes Reguladoras de Genes , Antígenos de Histocompatibilidad Clase I/metabolismo , Interacciones Huésped-Patógeno , Humanos , Inmunidad Innata/genética , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Subfamilia K de Receptores Similares a Lectina de Células NK/fisiología , ARN Viral/fisiología
13.
J Exp Med ; 219(7)2022 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-35670812

RESUMEN

Regulatory T (Treg) cells represent a specialized lineage of suppressive CD4+ T cells whose functionality is critically dependent on their ability to migrate to and dwell in the proximity of cells they control. Here we show that continuous expression of the chemokine receptor CXCR4 in Treg cells is required for their ability to accumulate in the bone marrow (BM). Induced CXCR4 ablation in Treg cells led to their rapid depletion and consequent increase in mature B cells, foremost the B-1 subset, observed exclusively in the BM without detectable changes in plasma cells or hematopoietic stem cells or any signs of systemic or local immune activation elsewhere. Dysregulation of BM B-1 B cells was associated with a highly specific increase in IgM autoantibodies and total serum IgM levels. Thus, Treg cells control autoreactive B-1 B cells in a CXCR4-dependent manner. These findings have significant implications for understanding the regulation of B cell autoreactivity and malignancies.


Asunto(s)
Subgrupos de Linfocitos B , Linfocitos T Reguladores , Subgrupos de Linfocitos B/metabolismo , Médula Ósea/metabolismo , Células de la Médula Ósea/metabolismo , Inmunoglobulina M/metabolismo , Receptores CXCR4/metabolismo
14.
Respir Care ; 56(10): 1611-3, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21513610

RESUMEN

We describe the case of a woman who presented to the intensive care unit with acute respiratory failure that required mechanical ventilation. She had severe pulmonary hypertension secondary to interstitial lung disease, and her history included sarcoidosis and tuberculosis. She was dependent on inhaled nitric oxide (INO) to maintain safe arterial oxygen saturation and could not be weaned from mechanical ventilation. Echocardiography revealed a patent foramen ovale with substantial right-to-left shunt, which probably contributed to her hypoxemia. Sildenafil enabled weaning from INO and substantially reduced the flow through the patent foramen ovale. She was successfully extubated and discharged home. To our knowledge, this is the first report of weaning from INO and mechanical ventilation in a patient with both severe secondary pulmonary hypertension and a right-to-left shunt through a patent foramen ovale.


Asunto(s)
Broncodilatadores/administración & dosificación , Hipertensión Pulmonar/terapia , Óxido Nítrico/administración & dosificación , Piperazinas/uso terapéutico , Insuficiencia Respiratoria/etiología , Sulfonas/uso terapéutico , Vasodilatadores/uso terapéutico , Desconexión del Ventilador/métodos , Anciano , Comorbilidad , Disnea/etiología , Femenino , Foramen Oval Permeable/epidemiología , Humanos , Hipertensión Pulmonar/complicaciones , Hipertensión Pulmonar/epidemiología , Inhibidores de Fosfodiesterasa 5/administración & dosificación , Inhibidores de Fosfodiesterasa 5/uso terapéutico , Piperazinas/administración & dosificación , Purinas/administración & dosificación , Purinas/uso terapéutico , Sarcoidosis Pulmonar/complicaciones , Citrato de Sildenafil , Sulfonas/administración & dosificación , Vasodilatadores/administración & dosificación
15.
NAR Cancer ; 3(3): zcab029, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34316716

RESUMEN

Enhancer demethylation in leukemia has been shown to lead to overexpression of genes which promote cancer characteristics. The vascular endothelial growth factor A (VEGFA) enhancer, located 157 Kb downstream of its promoter, is demethylated in chronic myeloid leukemia (CML). VEGFA has several alternative splicing isoforms with different roles in cancer progression. Since transcription and splicing are coupled, we wondered whether VEGFA enhancer activity can also regulate the gene's alternative splicing to contribute to the pathology of CML. Our results show that mutating the VEGFA +157 enhancer promotes exclusion of exons 6a and 7 and activating the enhancer by tethering a chromatin activator has the opposite effect. In line with these results, CML patients present with high expression of +157 eRNA and inclusion of VEGFA exons 6a and 7. In addition, our results show that the positive regulator of RNAPII transcription elongation, CCNT2, binds VEGFA's promoter and enhancer, and its silencing promotes exclusion of exons 6a and 7 as it slows down RNAPII elongation rate. Thus our results suggest that VEGFA's +157 enhancer regulates its alternative splicing by increasing RNAPII elongation rate via CCNT2. Our work demonstrates for the first time a connection between an endogenous enhancer and alternative splicing regulation of its target gene.

16.
J Vis Exp ; (143)2019 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-30663643

RESUMEN

Interactions between receptors and ligands constitute a fundamental biological process. However, direct experiments with cells that express the native receptor and the ligand are challenging since the ligand of a specific receptor may be unknown and experimental procedures with the native ligand can be technically complicated. To address these obstacles, we describe a reporter system to detect the binding and activation of a specific receptor by a ligand of interest. In this reporter system, the extracellular domain of a specific receptor is conjugated to mouse CD3ζ and this chimeric protein is then expressed in mouse BW cells. These transfected BW cells can then be incubated with different targets (e.g., cells or antibodies). Activation of a transfected receptor leads to the secretion of mouse interleukin-2 (mIL-2) which can be detected by enzyme-linked immunosorbent assay (ELISA). This reporter system has the advantages of being sensitive and specific to a single receptor. In addition, the activation level of a specific receptor can easily be quantified and can be used even in cases where the ligand of the receptor is unknown. This system has been implemented successfully in many of our studies to characterize receptor-ligand interactions. We have recently employed this system to study the activation of human Fcγ receptors (FcγRs) by different monoclonal anti-CD20 antibodies in clinical use.


Asunto(s)
Sistemas de Liberación de Medicamentos/métodos , Ensayo de Inmunoadsorción Enzimática/métodos , Animales , Humanos , Ligandos , Ratones , Transfección
17.
Clin Biomech (Bristol, Avon) ; 65: 87-91, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-31005694

RESUMEN

BACKGROUND: Functional scores and radiographs are often used to assess function and predict development of osteoarthritis in patients with multi-fragmentary tibial plateau fractures (TPFs). Locomotion, which is the primary goal of fracture treatment, is rarely assessed. The objective of this study was to assess functional ability of patients after TPF fixation using spatio-temporal gait analysis (STGA), and to compare STGA variables with self-reported functional scores and preoperative fracture characteristics. METHODS: Preoperative CT scans of 21 patients with complete articular multi-fragmentary TPFs were evaluated for number of fragments, maximum gap between the fragments and maximum articular depression. All patients underwent STGA (velocity, cadence, step length of the affected and the unaffected leg, single-limb support by the affected and the unaffected leg, and double-leg support) and filled the Knee Society Score and the Short Form-12 questionnaires on average 3 years (SD = 1.56, range, 2-5.8) post-injury. FINDINGS: Step length and single-limb support time of the affected leg were shorter compared to the unaffected leg (p = 0.02 and p = 0.007, respectively). Number of fracture fragments correlated with cadence (R = -0.461, p = 0.04) and velocity (R = -0.447, p = 0.04). INTERPRETATION: Given that both higher fracture comminution and deformity on the one hand and the above gait parameter alterations on the other hand are associated with knee osteoarthritis, STGA may be used for routine postoperative evaluation of patients after TPF fixation.


Asunto(s)
Fijación Interna de Fracturas , Marcha/fisiología , Fracturas de la Tibia , Adulto , Fenómenos Biomecánicos , Femenino , Fijación Interna de Fracturas/métodos , Humanos , Articulación de la Rodilla/fisiopatología , Masculino , Persona de Mediana Edad , Osteoartritis de la Rodilla/fisiopatología , Radiografía , Estudios Retrospectivos , Encuestas y Cuestionarios , Fracturas de la Tibia/diagnóstico por imagen , Fracturas de la Tibia/fisiopatología , Fracturas de la Tibia/cirugía , Tomografía Computarizada por Rayos X
18.
J Neurosci ; 27(10): 2525-38, 2007 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-17344390

RESUMEN

The neurons of many basal ganglia nuclei, including the external and internal globus pallidus (GPe and GPi, respectively) and the substantia nigra pars reticulata (SNr) are characterized by their high-frequency (50-100 spikes/s) tonic discharge (HFD). However, the high firing rate of GPe neurons is interrupted by long pauses. We studied the extracellularly recorded spiking activity of 212 well-isolated HFD GPe and 52 GPi/SNr neurons from five monkeys during different states of behavioral activity. An algorithm that maximizes the surprise function was used to detect pauses and pauser cells ("pausers"). Only 6% of the GPi/SNr neurons versus as many as 56% of the GPe neurons were classified as pausers. The GPe average pause duration equals 0.62 s. The interpause intervals follow a Poissonian distribution with a frequency of 13 pauses/minute. No linear relationship was found between pause parameters (duration or frequency) and the firing rate of the cell. Pauses were preceded by various changes in firing rate but not dominantly by a decrease. The average amplitude and duration of the spike waveform was modulated only after the pause but not before it. Pauses of pairs of cells that were recorded simultaneously were not correlated. The probability of GPe cells to pause spontaneously was extremely variable among monkeys (30-90%) and inversely related to the degree of the monkey's motor activity. These findings suggest that spontaneous GPe pauses are related to low-arousal periods and are generated by a process that is independent of the discharge properties of the cells.


Asunto(s)
Globo Pálido/fisiología , Neuronas/fisiología , Potenciales de Acción , Algoritmos , Animales , Nivel de Alerta/fisiología , Conducta Animal/fisiología , Chlorocebus aethiops , Electrofisiología/estadística & datos numéricos , Femenino , Macaca fascicularis , Masculino , Distribución de Poisson , Tiempo de Reacción , Factores de Tiempo
19.
Oncoimmunology ; 7(6): e1428158, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29872553

RESUMEN

Treatment with monoclonal antibodies has revolutionized clinical medicine, especially in the fields of cancer and immunology. One of the oldest antibodies, which is widely used for the treatment of lymphomas and autoimmune diseases, is the anti-CD20 antibody rituximab. In recent years, new antibodies against CD20 have been developed including ofatumumab and obinutuzumab. An important mechanism of action of therapeutic monoclonal antibodies is activation of immune cells via Fc receptors (FcγRs). However, surprisingly, little is known about triggering of FcγRs by different therapeutic antibodies in general and anti-CD20 antibodies in particular. Here we establish a reporter assay to assess whether a particular antibody activates a certain Fc receptor. Using this assay we corroborated previous reports demonstrating obinutuzumab's ability to highly activate FcγRIIIa (CD16a). Importantly, we discovered that obinutuzumab also activates FcγRI (CD64) significantly more than rituximab and ofatumumab in response to chronic lymphocytic leukemia (CLL) cells obtained from patients. Mechanistically we show that this is due to the lack of FcγRIIb-mediated internalization of obinutuzumab following binding to CD20. Moreover, we show that obinutuzumab induces increased phagocytosis by primary macrophages in an FcγRI-dependent manner. Beyond the discovery of a new mechanism of obinutuzumab activity, the reporter assay can be applied to other therapeutic antibodies and may assist in developing antibodies with improved immunological properties.

20.
J Neurosci Methods ; 163(2): 267-82, 2007 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-17477972

RESUMEN

There have been many approaches to the problem of detection and sorting of extra-cellularly recorded action potentials, but only a few methods actually quantify the quality of this fundamental process. In most cases, the quality assessment is based on the subjective judgment of human observers and the recorded units are divided into "well isolated" or "multi-unit" groups. This subjective evaluation precludes comprehensive assessment of single-unit studies since the most basic parameter, i.e. their data quality, is not explicitly defined. Here we propose objective measures to evaluate the quality of spike data, based on the time-stamps of the detected spikes and the high-frequency sampling of the analog signal of cortical and basal-ganglia data. We show that quantification of recording quality by the signal-to-noise ratio (SNR) may be misleading. The recording quality is better assessed by an isolation score that measures the overlap between the noise (non-spike) and the spike clusters. Furthermore, we use a nearest-neighbors algorithm to estimate the proportion of false positive and false negative classification errors. To validate these quality measures, we simulate spike detection and sorting errors and show that the scores are good predictors of the frequency of errors. The reliability of the isolation score is further verified by errors implanted in real basal ganglia data and by using different sorting algorithms. We conclude that quantitative measures of spike isolation can be obtained independently of the method used for spike detection and sorting, and recommend their reports in any study based on the activity of single neurons.


Asunto(s)
Potenciales de Acción/fisiología , Algoritmos , Encéfalo/fisiología , Electrofisiología/métodos , Neurofisiología/métodos , Procesamiento de Señales Asistido por Computador , Animales , Ganglios Basales/fisiología , Corteza Cerebral/fisiología , Chlorocebus aethiops , Electrodos , Espacio Extracelular/fisiología , Femenino , Macaca fascicularis , Masculino , Neuronas/fisiología
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