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1.
Acad Med ; 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38683902

RESUMEN

PURPOSE: The Johns Hopkins Physician-Scientist Training Program (PSTP) was implemented to overcome well-documented challenges in training and retaining physician-scientists by providing physician-scientist pathway training for residents and clinical fellows. The program's core tenets include monthly seminars, individualized feedback on project proposals, access to mentors, and institutional funding opportunities. This study evaluated the effectiveness and outcomes of the PTSP and provides a framework for replication. METHOD: A query of institutional demographic data and bibliometric variables of the PSTP participants (2017-2020) at a single academic medical center was conducted in 2021. In addition, a voluntary survey collected personal and program evaluation information. RESULTS: Of 145 PSTP scholars, 59 (41%) were women, and 41 (31%), 8 (6%), and 6 (5%) of scholars self-identified as Asian, Hispanic, and Black, respectively. Thirty-three (23%) scholars received PSTP research support or career development microgrants. Of 66 PSTP graduates, 29 (44%) remained at Johns Hopkins as clinical fellows or faculty. Of 48 PSTP graduates in a post-training position, 42 (88%) were in academia, with the majority, 29 (76%), holding the rank of assistant professor. Fifty-nine of 140 available participants responded to the survey (42% response rate). The top-cited reason for joining the PSTP was exposure to mentors and administration (50/58 respondents, 86%), followed by seeking scholarly opportunities (37/58 respondents, 64%). Most scholars intended to continue a career as a physician-scientist. CONCLUSIONS: The PSTP provides internal research support and institutional oversight. Although establishing close mentor-mentee relationships requires individualized approaches, the PSTP provided structured academic pathways that enhanced participating scholars' ability to apply for grants and jobs. The vast majority continued their careers as physician-scientists after training. In light of the national evidence of a "leaky physician-scientist pipeline," programs such as the PSTP can be critical to entry into early academic career positions and institutional retention.

2.
Cell Rep ; 34(3): 108627, 2021 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-33472080

RESUMEN

The JAK/STAT1 pathway is generally activated by cytokines, providing essential antiviral defense. Here, we identify that STAT1 activation is independent of cytokines and JAKs at the early infection stage of some viruses, including influenza A virus (IAV). Instead, STAT1 is activated mainly through spleen tyrosine kinase (Syk) downstream of retinoic acid-inducible gene-I/mitochondrial antiviral-signaling protein (RIG-I/MAVS) signaling. Syk deletion profoundly impairs immediate innate immunity, as evidenced by the finding that Syk deletion attenuates tyrosine phosphorylation of STAT1 and reduces the expressions of interferon-stimulated genes (ISGs) in vitro and in vivo. The antiviral response to IAV infection is also significantly suppressed in the STAT1Y701F knockin mice. The results demonstrate that STAT1 activation is dependent on Syk rather than the cytokine-activated JAK signaling at the early stage of viral infection, which is critical for initial antiviral immunity. Our finding provides insights into the complicated mechanisms underlying host immune responses to viral infection.


Asunto(s)
Inmunidad Innata/inmunología , Factor de Transcripción STAT1/inmunología , Quinasa Syk/inmunología , Virosis/inmunología , Animales , Chlorocebus aethiops , Femenino , Células HEK293 , Humanos , Ratones , Ratones Endogámicos C57BL , Células 3T3 NIH , Fosforilación , Quinasa Syk/metabolismo , Células Vero
4.
Nature ; 564(7735): 273-277, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30542164

RESUMEN

Cytokine release syndrome (CRS) is a life-threatening complication of several new immunotherapies used to treat cancers and autoimmune diseases1-5. Here we report that atrial natriuretic peptide can protect mice from CRS induced by such agents by reducing the levels of circulating catecholamines. Catecholamines were found to orchestrate an immunodysregulation resulting from oncolytic bacteria and lipopolysaccharide through a self-amplifying loop in macrophages. Myeloid-specific deletion of tyrosine hydroxylase inhibited this circuit. Cytokine release induced by T-cell-activating therapeutic agents was also accompanied by a catecholamine surge and inhibition of catecholamine synthesis reduced cytokine release in vitro and in mice. Pharmacologic catecholamine blockade with metyrosine protected mice from lethal complications of CRS resulting from infections and various biotherapeutic agents including oncolytic bacteria, T-cell-targeting antibodies and CAR-T cells. Our study identifies catecholamines as an essential component of the cytokine release that can be modulated by specific blockers without impairing the therapeutic response.


Asunto(s)
Catecolaminas/antagonistas & inhibidores , Catecolaminas/metabolismo , Citocinas/efectos adversos , Síndrome , Animales , Factor Natriurético Atrial/farmacología , Complejo CD3/antagonistas & inhibidores , Catecolaminas/biosíntesis , Citocinas/inmunología , Epinefrina/metabolismo , Femenino , Humanos , Inmunoterapia Adoptiva , Técnicas In Vitro , Estimación de Kaplan-Meier , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Células Mieloides/efectos de los fármacos , Células Mieloides/metabolismo , Norepinefrina/metabolismo , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T/metabolismo , Receptores de Antígenos de Linfocitos T/uso terapéutico , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología , Linfocitos T/metabolismo , alfa-Metiltirosina/farmacología
5.
J Health Organ Manag ; 32(1): 2-8, 2018 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-29508668

RESUMEN

Purpose The purpose of this paper is to offer six principles that health system leaders can apply to establish a governance and management system for the quality of care and patient safety. Design/methodology/approach Leaders of a large academic health system set a goal of high reliability and formed a quality board committee in 2011 to oversee quality and patient safety everywhere care was delivered. Leaders of the health system and every entity, including inpatient hospitals, home care companies, and ambulatory services staff the committee. The committee works with the management for each entity to set and achieve quality goals. Through this work, the six principles emerged to address management structures and processes. Findings The principles are: ensure there is oversight for quality everywhere care is delivered under the health system; create a framework to organize and report the work; identify care areas where quality is ambiguous or underdeveloped (i.e. islands of quality) and work to ensure there is reporting and accountability for quality measures; create a consolidated quality statement similar to a financial statement; ensure the integrity of the data used to measure and report quality and safety performance; and transparently report performance and create an explicit accountability model. Originality/value This governance and management system for quality and safety functions similar to a finance system, with quality performance documented and reported, data integrity monitored, and accountability for performance from board to bedside. To the authors' knowledge, this is the first description of how a board has taken this type of systematic approach to oversee the quality of care.


Asunto(s)
Consejo Directivo/organización & administración , Calidad de la Atención de Salud/organización & administración , Instituciones de Atención Ambulatoria/organización & administración , Servicios de Atención de Salud a Domicilio/organización & administración , Administración Hospitalaria , Humanos , Objetivos Organizacionales , Seguridad del Paciente/normas , Calidad de la Atención de Salud/normas
6.
JAMA Netw Open ; 1(7): e184273, 2018 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-30646347

RESUMEN

Importance: The Johns Hopkins Community Health Partnership was created to improve care coordination across the continuum in East Baltimore, Maryland. Objective: To determine whether the Johns Hopkins Community Health Partnership (J-CHiP) was associated with improved outcomes and lower spending. Design, Setting, and Participants: Nonrandomized acute care intervention (ACI) and community intervention (CI) Medicare and Medicaid participants were analyzed in a quality improvement study using difference-in-differences designs with propensity score-weighted and matched comparison groups. The study spanned 2012 to 2016 and took place in acute care hospitals, primary care clinics, skilled nursing facilities, and community-based organizations. The ACI analysis compared outcomes of participants in Medicare and Medicaid during their 90-day postacute episode with those of a propensity score-weighted preintervention group at Johns Hopkins Community Health Partnership hospitals and a concurrent comparison group drawn from similar Maryland hospitals. The CI analysis compared changes in outcomes of Medicare and Medicaid participants with those of a propensity score-matched comparison group of local residents. Interventions: The ACI bundle aimed to improve transition planning following discharge. The CI included enhanced care coordination and integrated behavioral support from local primary care sites in collaboration with community-based organizations. Main Outcomes and Measures: Utilization measures of hospital admissions, 30-day readmissions, and emergency department visits; quality of care measures of potentially avoidable hospitalizations, practitioner follow-up visits; and total cost of care (TCOC) for Medicare and Medicaid participants. Results: The CI group had 2154 Medicare beneficiaries (1320 [61.3%] female; mean age, 69.3 years) and 2532 Medicaid beneficiaries (1483 [67.3%] female; mean age, 55.1 years). For the CI group's Medicaid participants, aggregate TCOC reduction was $24.4 million, and reductions of hospitalizations, emergency department visits, 30-day readmissions, and avoidable hospitalizations were 33, 51, 36, and 7 per 1000 beneficiaries, respectively. The ACI group had 26 144 beneficiary-episodes for Medicare (13 726 [52.5%] female patients; mean patient age, 68.4 years) and 13 921 beneficiary-episodes for Medicaid (7392 [53.1%] female patients; mean patient age, 52.2 years). For the ACI group's Medicare participants, there was a significant reduction in aggregate TCOC of $29.2 million with increases in 90-day hospitalizations and 30-day readmissions of 11 and 14 per 1000 beneficiary-episodes, respectively, and reduction in practitioner follow-up visits of 41 and 29 per 1000 beneficiary-episodes for 7-day and 30-day visits, respectively. For the ACI group's Medicaid participants, there was a significant reduction in aggregate TCOC of $59.8 million and the 90-day emergency department visit rate decreased by 133 per 1000 episodes, but hospitalizations increased by 49 per 1000 episodes and practitioner follow-up visits decreased by 70 and 182 per 1000 episodes for 7-day and 30-day visits, respectively. In total, the CI and ACI were associated with $113.3 million in cost savings. Conclusions and Relevance: A care coordination model consisting of complementary bundled interventions in an urban academic environment was associated with lower spending and improved health outcomes.


Asunto(s)
Instituciones de Atención Ambulatoria , Servicios de Salud Comunitaria , Análisis Costo-Beneficio , Costos de la Atención en Salud , Hospitales , Aceptación de la Atención de Salud , Calidad de la Atención de Salud , Anciano , Baltimore , Servicios de Salud Comunitaria/economía , Servicios de Salud Comunitaria/normas , Ahorro de Costo , Servicio de Urgencia en Hospital , Femenino , Hospitalización , Humanos , Masculino , Medicaid , Medicare , Persona de Mediana Edad , Readmisión del Paciente , Atención Primaria de Salud , Mejoramiento de la Calidad , Instituciones de Cuidados Especializados de Enfermería , Estados Unidos
9.
Thromb Haemost ; 115(5): 969-78, 2016 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-26790499

RESUMEN

Adaptor proteins play a critical role in the assembly of signalling complexes after engagement of platelet receptors by agonists such as collagen, ADP and thrombin. Recently, using proteomics, the Dok (downstream of tyrosine kinase) adapter proteins were identified in human and mouse platelets. In vitro studies suggest that Dok-1 binds to platelet integrin ß3, but the underlying effects of Dok-1 on αIIbß3 signalling, platelet activation and thrombosis remain to be elucidated. In the present study, using Dok-1-deficient (Dok-1-/-) mice, we determined the phenotypic role of Dok-1 in αIIbß3 signalling. We found that platelets from Dok-1-/- mice displayed normal aggregation, activation of αIIbß3 (assessed by binding of JON/A), P-selectin surface expression (assessed by anti-CD62P), and soluble fibrinogen binding. These findings indicate that Dok-1 does not affect "inside-out" platelet signalling. Compared with platelets from wild-type (WT) mice, platelets from Dok-1-/- mice exhibited increased clot retraction (p < 0.05 vs WT), increased PLCγ2 phosphorylation, and enhanced spreading on fibrinogen after thrombin stimulation (p < 0.01 vs WT), demonstrating that Dok-1 negatively regulates αIIbß3 "outside-in" signalling. Finally, we found that Dok-1-/- mice exhibited significantly shortened bleeding times and accelerated carotid artery thrombosis in response to photochemical injury (p < 0.05 vs WT mice). We conclude that Dok-1 modulates thrombosis and haemostasis by negatively regulating αIIbß3 outside-in signalling.


Asunto(s)
Proteínas de Unión al ADN/sangre , Fosfoproteínas/sangre , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/metabolismo , Proteínas de Unión al ARN/sangre , Trombosis/prevención & control , Animales , Tiempo de Sangría , Trombosis de las Arterias Carótidas/sangre , Trombosis de las Arterias Carótidas/genética , Trombosis de las Arterias Carótidas/prevención & control , Retracción del Coagulo , Proteínas de Unión al ADN/deficiencia , Proteínas de Unión al ADN/genética , Fibrinógeno/metabolismo , Hemostasis , Humanos , Ratones , Ratones de la Cepa 129 , Ratones Noqueados , Selectina-P/sangre , Fosfolipasa C gamma/sangre , Fosfoproteínas/deficiencia , Fosfoproteínas/genética , Activación Plaquetaria , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/antagonistas & inhibidores , Proteínas de Unión al ARN/genética , Transducción de Señal , Trombosis/sangre , Trombosis/genética
10.
J Clin Invest ; 125(9): 3316-20, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26241058
12.
J Immunol ; 194(3): 1011-20, 2015 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-25527786

RESUMEN

Donor T lymphocyte transfer with hematopoietic stem cells suppresses residual tumor growth (graft-versus-tumor [GVT]) in cancer patients undergoing bone marrow transplantation (BMT). However, donor T cell reactivity to host organs causes severe and potentially lethal inflammation called graft-versus-host disease (GVHD). High-dose steroids or other immunosuppressive drugs are used to treat GVHD that have limited ability to control the inflammation while incurring long-term toxicity. Novel strategies are needed to modulate GVHD, preserve GVT, and improve the outcome of BMT. Regulatory T cells (Tregs) control alloantigen-sensitized inflammation of GVHD, sustain GVT, and prevent mortality in BMT. Helminths colonizing the alimentary tract dramatically increase the Treg activity, thereby modulating intestinal or systemic inflammatory responses. These observations led us to hypothesize that helminths can regulate GVHD and maintain GVT in mice. Acute GVHD was induced in helminth (Heligmosomoides polygyrus)-infected or uninfected BALB/c recipients of C57BL/6 donor grafts. Helminth infection suppressed donor T cell inflammatory cytokine generation and reduced GVHD-related mortality, but maintained GVT. H. polygyrus colonization promoted the survival of TGF-ß-generating recipient Tregs after a conditioning regimen with total body irradiation and led to a TGF-ß-dependent in vivo expansion/maturation of donor Tregs after BMT. Helminths did not control GVHD when T cells unresponsive to TGF-ß-mediated immune regulation were used as donor T lymphocytes. These results suggest that helminths suppress acute GVHD using Tregs and TGF-ß-dependent pathways in mice. Helminthic regulation of GVHD and GVT through intestinal immune conditioning may improve the outcome of BMT.


Asunto(s)
Enfermedad Injerto contra Huésped/inmunología , Helmintos/inmunología , Intestinos/inmunología , Intestinos/parasitología , Neoplasias/inmunología , Enfermedad Aguda , Traslado Adoptivo , Animales , Trasplante de Médula Ósea , Citocinas/biosíntesis , Modelos Animales de Enfermedad , Enfermedad Injerto contra Huésped/metabolismo , Enfermedad Injerto contra Huésped/mortalidad , Helmintiasis Animal/inmunología , Inmunomodulación , Inmunofenotipificación , Masculino , Ratones , Neoplasias/metabolismo , Neoplasias/mortalidad , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Acondicionamiento Pretrasplante , Trasplante Homólogo
13.
Acad Med ; 90(2): 165-72, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25517699

RESUMEN

In this article, the authors describe an initiative that established an infrastructure to manage quality and safety efforts throughout a complex health care system and that improved performance on core measures for acute myocardial infarction, heart failure, pneumonia, surgical care, and children's asthma. The Johns Hopkins Medicine Board of Trustees created a governance structure to establish health care system-wide oversight and hospital accountability for quality and safety efforts throughout Johns Hopkins Medicine. The Armstrong Institute for Patient Safety and Quality was formed; institute leaders used a conceptual model nested in a fractal infrastructure to implement this initiative to improve performance at two academic medical centers and three community hospitals, starting in March 2012. The initiative aimed to achieve ≥ 96% compliance on seven inpatient process-of-care core measures and meet the requirements for the Delmarva Foundation and Joint Commission awards. The primary outcome measure was the percentage of patients at each hospital who received the recommended process of care. The authors compared health system and hospital performance before (2011) and after (2012, 2013) the initiative. The health system achieved ≥ 96% compliance on six of the seven targeted measures by 2013. Of the five hospitals, four received the Delmarva Foundation award and two received The Joint Commission award in 2013. The authors argue that, to improve quality and safety, health care systems should establish a system-wide governance structure and accountability process. They also should define and communicate goals and measures and build an infrastructure to support peer learning.


Asunto(s)
Atención a la Salud/organización & administración , Evaluación de Procesos, Atención de Salud , Mejoramiento de la Calidad/organización & administración , Centros Médicos Académicos , Adulto , Asma/terapia , Niño , Insuficiencia Cardíaca/terapia , Hospitalización , Hospitales Comunitarios , Humanos , Maryland , Infarto del Miocardio/terapia , Atención Perioperativa , Neumonía/terapia
14.
Elife ; 3: e01659, 2014 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-24714492

RESUMEN

Natural killer (NK) cells belong to the innate immune system; they can control virus infections and developing tumors by cytotoxicity and producing inflammatory cytokines. Most studies of mouse NK cells, however, have focused on conventional NK (cNK) cells in the spleen. Recently, we described two populations of liver NK cells, tissue-resident NK (trNK) cells and those resembling splenic cNK cells. However, their lineage relationship was unclear; trNK cells could be developing cNK cells, related to thymic NK cells, or a lineage distinct from both cNK and thymic NK cells. Herein we used detailed transcriptomic, flow cytometric, and functional analysis and transcription factor-deficient mice to determine that liver trNK cells form a distinct lineage from cNK and thymic NK cells. Taken together with analysis of trNK cells in other tissues, there are at least four distinct lineages of NK cells: cNK, thymic, liver (and skin) trNK, and uterine trNK cells. DOI: http://dx.doi.org/10.7554/eLife.01659.001.


Asunto(s)
Linaje de la Célula , Células Asesinas Naturales/inmunología , Hígado/inmunología , Piel/inmunología , Bazo/inmunología , Timo/inmunología , Útero/inmunología , Animales , Biomarcadores/metabolismo , Células Cultivadas , Femenino , Citometría de Flujo , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Inmunofenotipificación , Células Asesinas Naturales/metabolismo , Hígado/citología , Hígado/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Fenotipo , Piel/citología , Piel/metabolismo , Bazo/citología , Bazo/metabolismo , Timo/citología , Timo/metabolismo , Factores de Transcripción/deficiencia , Factores de Transcripción/genética , Útero/citología , Útero/metabolismo
15.
J Immunol ; 192(7): 3133-42, 2014 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-24567532

RESUMEN

T cell Ig and mucin domain (Tim) 3 is a surface molecule expressed throughout the immune system that can mediate both stimulatory and inhibitory effects. Previous studies have provided evidence that Tim-3 functions to enforce CD8 T cell exhaustion, a dysfunctional state associated with chronic stimulation. In contrast, the role of Tim-3 in the regulation of CD8 T cell responses to acute and transient stimulation remains undefined. To address this knowledge gap, we examined how Tim-3 affects CD8 T cell responses to acute Listeria monocytogenes infection. Analysis of wild-type (WT) mice infected with L. monocytogenes revealed that Tim-3 was transiently expressed by activated CD8 T cells and was associated primarily with acquisition of an effector phenotype. Comparison of responses to L. monocytogenes by WT and Tim-3 knockout (KO) mice showed that the absence of Tim-3 significantly reduced the magnitudes of both primary and secondary CD8 T cell responses, which correlated with decreased IFN-γ production and degranulation by Tim-3 KO cells stimulated with peptide Ag ex vivo. To address the T cell-intrinsic role of Tim-3, we analyzed responses to L. monocytogenes infection by WT and Tim-3 KO TCR-transgenic CD8 T cells following adoptive transfer into a shared WT host. In this setting, the accumulation of CD8 T cells and the generation of cytokine-producing cells were significantly reduced by the lack of Tim-3, demonstrating that this molecule has a direct effect on CD8 T cell function. Combined, our results suggest that Tim-3 can mediate a stimulatory effect on CD8 T cell responses to an acute infection.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Listeria monocytogenes/inmunología , Listeriosis/inmunología , Receptores Virales/inmunología , Traslado Adoptivo , Animales , Linfocitos T CD8-positivos/metabolismo , Linfocitos T CD8-positivos/trasplante , Proliferación Celular , Supervivencia Celular/genética , Supervivencia Celular/inmunología , Citometría de Flujo , Receptor 2 Celular del Virus de la Hepatitis A , Interacciones Huésped-Patógeno/inmunología , Interferón gamma/inmunología , Interferón gamma/metabolismo , Listeria monocytogenes/fisiología , Listeriosis/microbiología , Ratones , Ratones Congénicos , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T/inmunología , Receptores de Antígenos de Linfocitos T/metabolismo , Receptores Virales/genética , Receptores Virales/metabolismo , Factor de Necrosis Tumoral alfa/inmunología , Factor de Necrosis Tumoral alfa/metabolismo
16.
J Immunol ; 192(4): 1918-27, 2014 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-24442434

RESUMEN

NFIL3 is a transcription factor that regulates multiple immunologic functions. In myeloid cells, NFIL3 is IL-10 inducible and has a key role as a repressor of IL-12p40 transcription. NFIL3 is a susceptibility gene for the human inflammatory bowel diseases. In this article, we describe spontaneous colitis in Nfil3(-/-) mice. Mice lacking both Nfil3 and Il10 had severe early-onset colitis, suggesting that NFIL3 and IL-10 independently regulate mucosal homeostasis. Lymphocytes were necessary for colitis, because Nfil3/Rag1 double-knockout mice were protected from disease. However, Nfil3/Rag1 double-knockout mice adoptively transferred with wild-type CD4(+) T cells developed severe colitis compared with Rag1(-/-) recipients, suggesting that colitis was linked to defects in innate immune cells. Colitis was abrogated in Nfil3/Il12b double-deficient mice, identifying Il12b dysregulation as a central pathogenic event. Finally, germ-free Nfil3(-/-) mice do not develop colonic inflammation. Thus, NFIL3 is a microbiota-dependent, IL-10-independent regulator of mucosal homeostasis via IL-12p40.


Asunto(s)
Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Enfermedades Inflamatorias del Intestino/genética , Enfermedades Inflamatorias del Intestino/microbiología , Interleucina-10/genética , Subunidad p40 de la Interleucina-12/metabolismo , Subunidad p19 de la Interleucina-23/metabolismo , Microbiota/inmunología , Traslado Adoptivo , Animales , Proteínas de Arabidopsis/biosíntesis , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Células Cultivadas , Colon/inmunología , Colon/patología , Predisposición Genética a la Enfermedad , Subunidad p40 de la Interleucina-12/genética , Subunidad p19 de la Interleucina-23/genética , Proteínas de la Membrana/biosíntesis , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Células TH1/inmunología , Células Th17/inmunología , Factor de Necrosis Tumoral alfa/genética
17.
J Exp Med ; 210(13): 2981-90, 2013 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-24277151

RESUMEN

Development of the natural killer (NK) cell lineage is dependent on the transcription factor Nfil3 (or E4BP4), which is thought to act downstream of IL-15 signaling. Nfil3-deficient mice lack NK cells, whereas other lymphocyte lineages (B, T, and NKT cells) remain largely intact. We report the appearance of Ly49H-expressing NK cells in Nfil3(-/-) mice infected with mouse cytomegalovirus (MCMV) or recombinant viruses expressing the viral m157 glycoprotein. Nfil3(-/-) NK cells at the peak of antigen-driven expansion were functionally similar to NK cells from infected wild-type mice with respect to IFN-γ production and cytotoxicity, and could comparably produce long-lived memory NK cells that persisted in lymphoid and nonlymphoid tissues for >60 d. We demonstrate that generation and maintenance of NK cell memory is an Nfil3-independent but IL-15-dependent process. Furthermore, specific ablation of Nfil3 in either immature NK cells in the bone marrow or mature peripheral NK cells had no observable effect on NK cell lineage maintenance or homeostasis. Thus, expression of Nfil3 is crucial only early in the development of NK cells, and signals through activating receptors and proinflammatory cytokines during viral infection can bypass the requirement for Nfil3, promoting the proliferation and long-term survival of virus-specific NK cells.


Asunto(s)
Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Células Asesinas Naturales/citología , Animales , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Linaje de la Célula , Separación Celular , Supervivencia Celular , Citocinas/metabolismo , Citometría de Flujo , Regulación de la Expresión Génica , Homeostasis , Inflamación , Interferón gamma/metabolismo , Interleucina-15/metabolismo , Células Asesinas Naturales/virología , Ligandos , Activación de Linfocitos , Ratones , Ratones Endogámicos C57BL , Muromegalovirus/inmunología , Subfamilia A de Receptores Similares a Lectina de Células NK/metabolismo , Bazo/citología , Tamoxifeno/química
18.
Science ; 342(6159): 727-30, 2013 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-24202171

RESUMEN

Circadian clocks regulate numerous physiological processes that vary across the day-night (diurnal) cycle, but if and how the circadian clock regulates the adaptive immune system is mostly unclear. Interleukin-17-producing CD4(+) T helper (T(H)17) cells are proinflammatory immune cells that protect against bacterial and fungal infections at mucosal surfaces. Their lineage specification is regulated by the orphan nuclear receptor RORγt. We show that the transcription factor NFIL3 suppresses T(H)17 cell development by directly binding and repressing the Rorγt promoter. NFIL3 links T(H)17 cell development to the circadian clock network through the transcription factor REV-ERBα. Accordingly, TH17 lineage specification varies diurnally and is altered in Rev-erbα(-/-) mice. Light-cycle disruption elevated intestinal T(H)17 cell frequencies and increased susceptibility to inflammatory disease. Thus, lineage specification of a key immune cell is under direct circadian control.


Asunto(s)
Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Diferenciación Celular/genética , Relojes Circadianos/inmunología , Regulación de la Expresión Génica , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/genética , Células Th17/citología , Animales , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Proteínas CLOCK/genética , Linaje de la Célula/genética , Relojes Circadianos/genética , Vida Libre de Gérmenes , Células HEK293 , Humanos , Intestino Delgado/inmunología , Intestino Delgado/microbiología , Células Jurkat , Ratones , Ratones Endogámicos C57BL , Ratones Mutantes , Miembro 1 del Grupo D de la Subfamilia 1 de Receptores Nucleares/genética , Miembro 1 del Grupo D de la Subfamilia 1 de Receptores Nucleares/metabolismo , Regiones Promotoras Genéticas
19.
Cancer Res ; 73(15): 4898-908, 2013 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-23749639

RESUMEN

Alterations in translation occur in cancer cells, but the precise pathogenic processes and mechanistic underpinnings are not well understood. In this study, we report that interactions between Pim family kinases and the translation initiation factor eIF4B are critical for Abl oncogenicity. Pim kinases, Pim-1 and Pim-2, both directly phosphorylated eIF4B on Ser406 and Ser422. Phosphorylation of eIF4B on Ser422 was highly sensitive to pharmacologic or RNA interference-mediated inhibition of Pim kinases. Expression and phosphorylation of eIF4B relied upon Abl kinase activity in both v-Abl- and Bcr-Abl-expressing leukemic cells based on their blockade by the Abl kinase inhibitor imatinib. Ectopic expression of phosphomimetic mutants of eIF4B conferred resistance to apoptosis by the Pim kinase inhibitor SMI-4a in Abl-transformed cells. In contrast, silencing eIF4B sensitized Abl-transformed cells to imatinib-induced apoptosis and also inhibited their growth as engrafted tumors in nude mice. Extending these observations, we found that primary bone marrow cells derived from eIF4B-knockdown transgenic mice were less susceptible to Abl transformation, relative to cells from wild-type mice. Taken together, our results identify eIF4B as a critical substrate of Pim kinases in mediating the activity of Abl oncogenes, and they highlight eIF4B as a candidate therapeutic target for treatment of Abl-induced cancers.


Asunto(s)
Transformación Celular Neoplásica/metabolismo , Factores Eucarióticos de Iniciación/metabolismo , Genes abl/fisiología , Proteínas Proto-Oncogénicas c-pim-1/metabolismo , Animales , Línea Celular Tumoral , Técnicas de Silenciamiento del Gen , Humanos , Immunoblotting , Inmunoprecipitación , Ratones , Ratones Transgénicos , Neoplasias/metabolismo , Fosforilación , Ensayos Antitumor por Modelo de Xenoinjerto
20.
BMC Res Notes ; 6: 235, 2013 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-23767996

RESUMEN

BACKGROUND: SOCS7 is a member of the suppressor of cytokine signaling family of proteins and is expressed in skeletal muscle and islets. SOCS7 deficient mice develop islet hyperplasia in the setting of increased insulin sensitivity and normal glucose tolerance. The objective of this study was to determine if variants in SOCS7 play a role in variation of glucose and insulin levels and the development of type 2 diabetes (T2DM). RESULTS: Five SOCS7 tagging SNPs were genotyped in diabetic and nondiabetic Old Order Amish. A case-control study was performed in T2DM (n = 145) and normal glucose tolerant (n = 358) subjects. Nominal associations were observed with T2DM and the minor alleles for rs8068600 (P = 0.01) and rs8074124 (P = 0.04); however, only rs8068600 remained significant after Bonferroni adjustment for multiple comparisons (P = 0.01). Among nondiabetic Amish (n = 765), no significant associations with glucose or insulin traits including fasting or 2 hour glucose and insulin from the oral glucose tolerance test, insulin or glucose area under the curve, Matsuda Index or HOMA-IR were found for any of the SNPs. CONCLUSION: In conclusion, genetic variants in the SOCS7 gene do not impact variation in glucose homeostasis traits and only minimally impact risk of T2DM in the Old Order Amish. Our study was not able to address whether rare variants that potentially impact gene function might influence T2DM risk.


Asunto(s)
Glucosa/metabolismo , Homeostasis , Proteínas Nucleares/genética , Polimorfismo Genético , Proteínas Supresoras de la Señalización de Citocinas/genética , Anciano , Estudios de Casos y Controles , Diabetes Mellitus Tipo 2/genética , Femenino , Humanos , Masculino , Persona de Mediana Edad
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