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1.
Hum Mutat ; 43(12): 1780-1794, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36251279

RESUMEN

The Multiple Endocrine Neoplasia type 2 (MEN2) RET proto-oncogene database, originally published in 2008, is a comprehensive repository of all publicly available RET gene variations associated with MEN2 syndromes. The variant-specific genotype/phenotype information, age of earliest reported medullary thyroid carcinoma (MTC) onset, and relevant references with a brief summary of findings are cataloged. The ACMG/AMP 2015 consensus statement on variant classification was modified specifically for MEN2 syndromes and RET variants using ClinGen sequence variant interpretation working group recommendations and ClinGen expert panel manuscripts, as well as manuscripts from the American Thyroid Association Guidelines Task Force on Medullary Thyroid Carcinoma and other MEN2 RET literature. The classifications for the 166 single unique variants in the MEN2 RET database were reanalyzed using the MEN2 RET specifically modified ACMG/AMP classification guidelines (version 1). Applying these guidelines added two new variant classifications to the database (likely benign and likely pathogenic) and resulted in clinically significant classification changes (e.g., from pathogenic to uncertain) in 15.7% (26/166) of the original variants. Of those clinically significant changes, the highest percentage of changes, 46.2% (12/26), were changes from uncertain to benign or likely benign. The modified ACMG/AMP criteria with MEN2 RET specifications will optimize and standardize RET variant classifications.


Asunto(s)
Carcinoma Medular , Neoplasia Endocrina Múltiple Tipo 2a , Neoplasias de la Tiroides , Humanos , Neoplasia Endocrina Múltiple Tipo 2a/genética , Neoplasia Endocrina Múltiple Tipo 2a/patología , Carcinoma Medular/genética , Proteínas Proto-Oncogénicas c-ret/genética , Síndrome , Neoplasias de la Tiroides/diagnóstico , Neoplasias de la Tiroides/genética , Adenosina Monofosfato
2.
Biomedicines ; 10(3)2022 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-35327363

RESUMEN

The evidence for an environmental component in chronic psychotic disorders is strong and research on the epigenetic manifestations of these environmental impacts has commenced in earnest. In reviewing this research, the focus is on three genes as models for differential methylation, MCHR1, AKT1 and TDO2, each of which have been investigated for genetic association with psychotic disorders. Environmental factors associated with psychotic disorders, and which interact with these model genes, are explored in depth. The location of transcription factor motifs relative to key methylation sites is evaluated for predicted gene expression results, and for other sites, evidence is presented for methylation directing alternative splicing. Experimental results from key studies show differential methylation: for MCHR1, in psychosis cases versus controls; for AKT1, as a pre-existing methylation pattern influencing brain activation following acute administration of a psychosis-eliciting environmental stimulus; and for TDO2, in a pattern associated with a developmental factor of risk for psychosis, in all cases the predicted expression impact being highly dependent on location. Methylation induced by smoking, a confounding variable, exhibits an intriguing pattern for all three genes. Finally, how differential methylation meshes with Darwinian principles is examined, in particular as it relates to the "flexible stem" theory of evolution.

3.
J Exp Med ; 218(6)2021 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-33914024

RESUMEN

For the large array of self-peptide/MHC class II (pMHC-II) complexes displayed in the body, it is unclear whether CD4+ T cell tolerance must be imparted for each individual complex or whether pMHC-II-nonspecific bystander mechanisms are sufficient to confer tolerance by acting broadly on T cells reactive to multiple self-pMHC-II ligands. Here, via reconstitution of T cell-deficient mice, we demonstrate that altered T cell selection on a single prostate-specific self-pMHC-II ligand renders recipient mice susceptible to prostate-specific T cell infiltration. Mechanistically, this self-pMHC-II complex is required for directing antigen-specific cells into the Foxp3+ regulatory T cell lineage but does not induce clonal deletion to a measurable extent. Thus, our data demonstrate that polyclonal T reg cells are unable to functionally compensate for a breach in tolerance to a single self-pMHC-II complex in this setting, revealing vulnerabilities in antigen-nonspecific bystander mechanisms of immune tolerance.


Asunto(s)
Linfocitos T Reguladores/inmunología , Animales , Antígenos/inmunología , Linfocitos T CD4-Positivos/inmunología , Línea Celular , Células Dendríticas/inmunología , Antígenos de Histocompatibilidad Clase II/inmunología , Tolerancia Inmunológica/inmunología , Insectos , Ligandos , Activación de Linfocitos/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Péptidos/inmunología
4.
Can Geriatr J ; 24(1): 73-76, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33680264

RESUMEN

The COVID-19 pandemic has recently put a stop to elective surgical procedures across Canada, inherently compounding already lengthy waitlists that exist within most disciplines of surgery. These long waits for elective procedures within Canadian provinces have not been caused by the COVID-19 pandemic; it is an acute-on-chronic issue that has been exacerbated by the ongoing COVID-19 pandemic. As hospitals begin to reschedule elective surgeries, patients are likely to be prioritized by clinical urgency using both established and newly created surgical triage severity scales. The objective of this commentary is to discuss issues related to the rebooking of elderly surgical patients during the COVID-19 pandemic within the context of northern medicine. Northern and rural hospitals may already face a multitude of barriers related to the rebooking of surgical patients due to a paucity of available surgical resources, as well as difficulties related to accessing care at the local level. While current surgical rebooking tools have been developed in response to the COVID-19 pandemic, they fail to explore certain risks related to the older adult population which may lead to increased mortality and morbidity. Review of the literature indicates that redistribution of surgical resources for older adults in the COVID-19 era will require consideration of clinical medical ethics vs. population health ethics regarding who should be prioritized in re-bookings for elective surgical procedures. This should be done in conjunction with encompassing surgical triage severity scales specifically made for older adults in the time of COVID-19.

5.
J Genet Couns ; 30(2): 606-615, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33135283

RESUMEN

Expanded carrier screening (ECS) is increasingly offered to a broader population and raises challenges of how to best educate and counsel the volume of screened individuals. For this study, we compared three educational tools (brochure, video and comic) about ECS on knowledge and decision making. A convenience online sample of 151 pregnant women was randomized to one of three groups (Video, n = 42; Comic n = 54; Brochure n = 55). Knowledge scores were significantly higher for the comic group compared to the video or the brochure groups (p < .001). No significant differences in preparation for decision making, decisional conflict, or perceptions of shared decision making were identified between the study groups. This study suggests that a comic about ECS may improve patient attention and retention of information. The use of graphic narratives may enable individuals to better understand medical information in general.


Asunto(s)
Conocimiento , Tamizaje Masivo , Toma de Decisiones , Escolaridad , Femenino , Tamización de Portadores Genéticos , Humanos , Embarazo
6.
Nat Immunol ; 21(5): 567-577, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32284593

RESUMEN

Unprimed mice harbor a substantial population of 'memory-phenotype' CD8+ T cells (CD8-MP cells) that exhibit hallmarks of activation and innate-like functional properties. Due to the lack of faithful markers to distinguish CD8-MP cells from bona fide CD8+ memory T cells, the developmental origins and antigen specificities of CD8-MP cells remain incompletely defined. Using deep T cell antigen receptor (TCR) sequencing, we found that the TCRs expressed by CD8-MP cells are highly recurrent and distinct from the TCRs expressed by naive-phenotype CD8+ T cells. CD8-MP clones exhibited reactivity to widely expressed self-ligands. T cell precursors expressing CD8-MP TCRs showed upregulation of the transcription factor Eomes during maturation in the thymus, prior to induction of the full memory phenotype, which is suggestive of a unique program triggered by recognition of self-ligands. Moreover, CD8-MP cells infiltrate oncogene-driven prostate tumors and express high densities of PD-1, which suggests potential roles in antitumor immunity and the response to immunotherapy.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Neoplasias de la Próstata/inmunología , Receptores de Antígenos de Linfocitos T/genética , Proteínas de Dominio T Box/metabolismo , Timo/fisiología , Animales , Autoantígenos/inmunología , Diferenciación Celular , Selección Clonal Mediada por Antígenos , Células Clonales , Memoria Inmunológica , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Receptor de Muerte Celular Programada 1/metabolismo , Proteínas de Dominio T Box/genética , Regulación hacia Arriba
7.
Annu Rev Immunol ; 38: 421-453, 2020 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-31990619

RESUMEN

Foxp3-expressing CD4+ regulatory T (Treg) cells play key roles in the prevention of autoimmunity and the maintenance of immune homeostasis and represent a major barrier to the induction of robust antitumor immune responses. Thus, a clear understanding of the mechanisms coordinating Treg cell differentiation is crucial for understanding numerous facets of health and disease and for developing approaches to modulate Treg cells for clinical benefit. Here, we discuss current knowledge of the signals that coordinate Treg cell development, the antigen-presenting cell types that direct Treg cell selection, and the nature of endogenous Treg cell ligands, focusing on evidence from studies in mice. We also highlight recent advances in this area and identify key unanswered questions.


Asunto(s)
Diferenciación Celular/inmunología , Linfopoyesis/inmunología , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Animales , Presentación de Antígeno/inmunología , Células Presentadoras de Antígenos/inmunología , Células Presentadoras de Antígenos/metabolismo , Biomarcadores , Diferenciación Celular/genética , Supresión Clonal , Selección Clonal Mediada por Antígenos , Humanos , Activación de Linfocitos/genética , Activación de Linfocitos/inmunología , Linfopoyesis/genética , Subgrupos de Linfocitos T/citología , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Linfocitos T Reguladores/citología , Timo/citología , Timo/inmunología , Timo/metabolismo
8.
PLoS Med ; 15(9): e1002655, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30265679

RESUMEN

BACKGROUND: Intravaginal rings (IVRs) for HIV pre-exposure prophylaxis (PrEP) theoretically overcome some adherence concerns associated with frequent dosing that can occur with oral or vaginal film/gel regimens. An innovative pod-IVR, composed of an elastomer scaffold that can hold up to 10 polymer-coated drug cores (or "pods"), is distinct from other IVR designs as drug release from each pod can be controlled independently. A pod-IVR has been developed for the delivery of tenofovir (TFV) disoproxil fumarate (TDF) in combination with emtricitabine (FTC), as daily oral TDF-FTC is the only Food and Drug Administration (FDA)-approved regimen for HIV PrEP. A triple combination IVR building on this platform and delivering TDF-FTC along with the antiretroviral (ARV) agent maraviroc (MVC) also is under development. METHODOLOGY AND FINDINGS: This pilot Phase I trial conducted between June 23, 2015, and July 15, 2016, evaluated the safety, pharmacokinetics (PKs), and acceptability of pod-IVRs delivering 3 different ARV regimens: 1) TDF only, 2) TDF-FTC, and 3) TDF-FTC-MVC over 7 d. The crossover, open-label portion of the trial (N = 6) consisted of 7 d of continuous TDF pod-IVR use, a wash-out phase, and 7 d of continuous TDF-FTC pod-IVR use. After a 3-mo pause to evaluate safety and PK of the TDF and TDF-FTC pod-IVRs, TDF-FTC-MVC pod-IVRs (N = 6) were evaluated over 7 d of continuous use. Safety was assessed by adverse events (AEs), colposcopy, and culture-independent analysis of the vaginal microbiome (VMB). Drug and drug metabolite concentrations in plasma, cervicovaginal fluids (CVFs), cervicovaginal lavages (CVLs), and vaginal tissue (VT) biopsies were determined via liquid chromatographic-tandem mass spectrometry (LC-MS/MS). Perceptibility and acceptability were assessed by surveys and interviews. Median participant age was as follows: TDF/TDF-FTC group, 26 y (range 24-35 y), 2 White, 2 Hispanic, and 2 African American; TDF-FTC-MVC group, 24.5 y (range 21-41 y), 3 White, 1 Hispanic, and 2 African American. Reported acceptability was high for all 3 products, and pod-IVR use was confirmed by residual drug levels in used IVRs. There were no serious adverse events (SAEs) during the study. There were 26 AEs reported during TDF/TDF-FTC IVR use (itching, discharge, discomfort), with no differences between TDF alone or in combination with FTC observed. In the TDF-FTC-MVC IVR group, there were 12 AEs (itching, discharge, discomfort) during IVR use regardless of attribution to study product. No epithelial disruption/thinning was seen by colposcopy, and no systematic VMB shifts were observed. Median (IQR) tenofovir diphosphate (TFV-DP) tissue concentrations of 303 (277-938) fmol/10(6) cells (TDF), 289 (110-603) fmol/10(6) cells (TDF-FTC), and 302 (177.1-823.8) fmol/10(6) cells (TDF-FTC-MVC) were sustained for 7 d, exceeding theoretical target concentrations for vaginal HIV prevention. The study's main limitations include the small sample size, short duration (7 d versus 28 d), and the lack of FTC triphosphate measurements in VT biopsies. CONCLUSIONS: An innovative pod-IVR delivery device with 3 different formulations delivering different regimens of ARV drugs vaginally appeared to be safe and acceptable and provided drug concentrations in CVFs and tissues exceeding concentrations achieved by highly protective oral dosing, suggesting that efficacy for vaginal HIV PrEP is achievable. These results show that an alternate, more adherence-independent, longer-acting prevention device based on the only FDA-approved PrEP combination regimen can be advanced to safety and efficacy testing. TRIAL REGISTRATION: ClinicalTrials.gov NCT02431273.


Asunto(s)
Fármacos Anti-VIH/administración & dosificación , Infecciones por VIH/prevención & control , VIH-1 , Profilaxis Pre-Exposición/métodos , Administración Intravaginal , Adulto , Fármacos Anti-VIH/efectos adversos , Fármacos Anti-VIH/farmacocinética , Dispositivos Anticonceptivos Femeninos , Estudios Cruzados , Composición de Medicamentos , Sistemas de Liberación de Medicamentos , Emtricitabina/administración & dosificación , Emtricitabina/efectos adversos , Emtricitabina/farmacocinética , Femenino , Humanos , Maraviroc/administración & dosificación , Maraviroc/efectos adversos , Maraviroc/farmacocinética , Satisfacción del Paciente , Tenofovir/administración & dosificación , Tenofovir/efectos adversos , Tenofovir/farmacocinética , Adulto Joven
9.
J Zoo Wildl Med ; 48(1): 241-244, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28363070

RESUMEN

Multihormonal pancreatic islet cell carcinomas were found in one female and two male captive geriatric Komodo dragons (Varanus komodoensis). Gross changes in the pancreas were visible in two of the cases. Clinical signs noted in the Komodo dragons were lethargy, weakness, and anorexia. Histologically, the tumors were comprised of nests and cords of well-differentiated neoplastic islet cells with scant amounts of eosinophilic cytoplasm and round, euchromatic nuclei, with rare mitoses. Infiltration by the islet cell tumor into the surrounding acinar tissue was observed in all cases, but no metastatic foci were seen. Multihormone expression was observed in all tumors, which labeled strongly positive for glucagon and somatostatin and focally positive for polypeptide. Pancreatic islet cell neoplasms should be considered in the differential diagnosis for geriatric Komodo dragons presenting with weakness, lethargy, and poor appetite.


Asunto(s)
Carcinoma de Células de los Islotes Pancreáticos/veterinaria , Lagartos , Neoplasias Pancreáticas/veterinaria , Animales , Carcinoma de Células de los Islotes Pancreáticos/patología , Resultado Fatal , Femenino , Masculino , Neoplasias Hormono-Dependientes , Neoplasias Pancreáticas/patología
10.
J Immunol ; 198(9): 3436-3447, 2017 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-28314855

RESUMEN

Inflammatory bone resorption mediated by osteoclasts is a major cause of morbidity and disability in many inflammatory disorders, including rheumatoid arthritis (RA). The mechanisms that regulate osteoclastogenesis and bone resorption in inflammatory settings are complex and have not been well elucidated. In this study, we identify the immunoregulator differentially expressed in FDCP 6 homolog (Def6) as a novel inhibitor of osteoclastogenesis in physiological and inflammatory conditions. Def6 deficiency in Def6-/- mice enhanced the sensitivity of osteoclast precursors to the physiological osteoclastogenic inducer receptor activator for NF-κB ligand, and Def6-/- osteoclasts formed actin rings. Furthermore, Def6 deficiency markedly increased TNF-α-induced osteoclastogenesis in vitro and in vivo and enhanced bone resorption in an inflammatory osteolysis mouse model. TNF-α serum levels correlated negatively with Def6 expression levels in osteoclast precursors obtained from RA patients, and the osteoclastogenic capacity of the osteoclast precursors was significantly inversely correlated with their Def6 expression levels, indicating that Def6 functions as an inhibitor of excessive osteoclast formation and bone destruction in RA. Mechanistically, Def6 suppressed osteoclastogenesis and the expression of key osteoclastogenic factors NFATc1, B lymphocyte-induced maturation protein-1, and c-Fos by regulating an endogenous IFN-ß-mediated autocrine feedback loop. The Def6-dependent pathway may represent a novel therapeutic target to prevent pathological bone destruction.


Asunto(s)
Artritis Reumatoide/metabolismo , Resorción Ósea/inmunología , Proteínas de Unión al ADN/metabolismo , Macrófagos/fisiología , Proteínas Nucleares/metabolismo , Osteoclastos/fisiología , Osteogénesis , Osteólisis/inmunología , Actinas/metabolismo , Animales , Artritis Reumatoide/genética , Comunicación Autocrina , Resorción Ósea/genética , Diferenciación Celular/genética , Células Cultivadas , Proteínas de Unión al ADN/genética , Modelos Animales de Enfermedad , Factores de Intercambio de Guanina Nucleótido , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Nucleares/genética , Osteogénesis/genética , Osteólisis/genética , Ligando RANK/inmunología
11.
Endocrinology ; 157(10): 4066-4075, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27526034

RESUMEN

Ligand-dependent actions of the vitamin D receptor (VDR) play a pleiotropic role in the regulation of innate and adaptive immunity. The liganded VDR is required for recruitment of macrophages during the inflammatory phase of cutaneous wound healing. Although the number of macrophages in the granulation tissue 2 days after wounding is markedly reduced in VDR knockout (KO) compared with wild-type mice, VDR ablation does not alter macrophage polarization. Parabiosis studies demonstrate that circulatory chimerism with wild-type mice is unable to rescue the macrophage defect in the wounds of VDR KO mice and reveal that wound macrophages are of local origin, regardless of VDR status. Wound cytokine analyses demonstrated a decrease in macrophage colony-stimulating factor (M-CSF) protein levels in VDR KO mice. Consistent with this, induction of M-CSF gene expression by TGFß and 1,25-dihydroxyvitamin D was impaired in dermal fibroblasts isolated from VDR KO mice. Because M-CSF is important for macrophage self-renewal, studies were performed to evaluate the response of tissue resident macrophages to this cytokine. A decrease in M-CSF induced proliferation and cyclin D1 expression was observed in peritoneal resident macrophages isolated from VDR KO mice, suggesting an intrinsic macrophage abnormality. Consistent with this, wound-healing assays in mice with macrophage-specific VDR ablation demonstrate that a normal wound microenvironment cannot compensate for the absence of the VDR in macrophages and thus confirm a critical role for the macrophage VDR in the inflammatory response to injury.


Asunto(s)
Macrófagos/fisiología , Receptores de Calcitriol/metabolismo , Cicatrización de Heridas/inmunología , Animales , Células Cultivadas , Citocinas/metabolismo , Femenino , Tejido de Granulación/inmunología , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados
12.
J Immunol ; 196(12): 4977-86, 2016 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-27183593

RESUMEN

Increased osteoclastogenesis is responsible for osteolysis, which is a severe consequence of inflammatory diseases associated with bone destruction, such as rheumatoid arthritis and periodontitis. The mechanisms that limit osteoclastogenesis under inflammatory conditions are largely unknown. We previously identified transcription factor RBP-J as a key negative regulator that restrains TNF-α-induced osteoclastogenesis and inflammatory bone resorption. In this study, we tested whether RBP-J suppresses inflammatory osteoclastogenesis by regulating the expression of microRNAs (miRNAs) important for this process. Using high-throughput sequencing of miRNAs, we obtained the first, to our knowledge, genome-wide profile of miRNA expression induced by TNF-α in mouse bone marrow-derived macrophages/osteoclast precursors during inflammatory osteoclastogenesis. Furthermore, we identified miR-182 as a novel miRNA that promotes inflammatory osteoclastogenesis driven by TNF-α and whose expression is suppressed by RBP-J. Downregulation of miR-182 dramatically suppressed the enhanced osteoclastogenesis program induced by TNF-α in RBP-J-deficient cells. Complementary loss- and gain-of-function approaches showed that miR-182 is a positive regulator of osteoclastogenic transcription factors NFATc1 and B lymphocyte-induced maturation protein-1. Moreover, we identified that direct miR-182 targets, Foxo3 and Maml1, play important inhibitory roles in TNF-α-mediated osteoclastogenesis. Thus, RBP-J-regulated miR-182 promotes TNF-α-induced osteoclastogenesis via inhibition of Foxo3 and Maml1. Suppression of miR-182 by RBP-J serves as an important mechanism that restrains TNF-α-induced osteoclastogenesis. Our results provide a novel miRNA-mediated mechanism by which RBP-J inhibits osteoclastogenesis and suggest that targeting of the newly described RBP-J-miR-182-Foxo3/Maml1 axis may represent an effective therapeutic approach to suppress inflammatory osteoclastogenesis and bone resorption.


Asunto(s)
Regulación de la Expresión Génica , Proteína de Unión a la Señal Recombinante J de las Inmunoglobulinas/metabolismo , MicroARNs/genética , Osteoclastos/metabolismo , Osteogénesis , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Resorción Ósea , Regulación hacia Abajo , Proteína Forkhead Box O3/genética , Proteína Forkhead Box O3/metabolismo , Proteína de Unión a la Señal Recombinante J de las Inmunoglobulinas/genética , Inflamación , Macrófagos/inmunología , Macrófagos/patología , Ratones , MicroARNs/antagonistas & inhibidores , Factores de Transcripción NFATC/genética , Factores de Transcripción NFATC/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Factor 1 de Unión al Dominio 1 de Regulación Positiva , Análisis de Secuencia de ARN , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores
13.
Clin Transl Sci ; 8(4): 330-3, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26053284

RESUMEN

Malnutrition is one of the earliest clinical manifestations of cystic fibrosis (CF) and is associated with poorer pulmonary and cognitive outcomes and survival later in life. Infant growth can be a responsive measure for clinical research in this age group if obtained and characterized accurately. We report here the methods to standardize and implement research-quality anthropometric measurement of infants with cystic fibrosis in the Baby Observational Nutrition Study multicenter trial.


Asunto(s)
Estatura , Peso Corporal , Fibrosis Quística/fisiopatología , Investigación Biomédica/normas , Cabeza/anatomía & histología , Humanos , Lactante
14.
J Immunol ; 194(10): 4784-95, 2015 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-25870244

RESUMEN

The thymus reaches its maximum size early in life and then begins to shrink, producing fewer T cells with increasing age. This thymic decline is thought to contribute to age-related T cell lymphopenias and hinder T cell recovery after bone marrow transplantation. Although several cellular and molecular processes have been implicated in age-related thymic involution, their relative contributions are not known. Using heterochronic parabiosis, we observe that young circulating factors are not sufficient to drive regeneration of the aged thymus. In contrast, we find that resupplying young, engraftable thymic epithelial cells (TECs) to a middle-aged or defective thymus leads to thymic growth and increased T cell production. Intrathymic transplantation and in vitro colony-forming assays reveal that the engraftment and proliferative capacities of TECs diminish early in life, whereas the receptivity of the thymus to TEC engraftment remains relatively constant with age. These results support a model in which thymic growth and subsequent involution are driven by cell-intrinsic changes in the proliferative capacity of TECs, and further show that young TECs can engraft and directly drive the growth of involuted thymuses.


Asunto(s)
Envejecimiento/fisiología , Células Epiteliales/trasplante , Timo/crecimiento & desarrollo , Animales , Proliferación Celular , Citometría de Flujo , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Parabiosis
15.
J Proteome Res ; 14(2): 1299-307, 2015 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-25411686

RESUMEN

We report the implementation of high-quality signal processing algorithms into ProteoWizard, an efficient, open-source software package designed for analyzing proteomics tandem mass spectrometry data. Specifically, a new wavelet-based peak-picker (CantWaiT) and a precursor charge determination algorithm (Turbocharger) have been implemented. These additions into ProteoWizard provide universal tools that are independent of vendor platform for tandem mass spectrometry analyses and have particular utility for intralaboratory studies requiring the advantages of different platforms convergent on a particular workflow or for interlaboratory investigations spanning multiple platforms. We compared results from these tools to those obtained using vendor and commercial software, finding that in all cases our algorithms resulted in a comparable number of identified peptides for simple and complex samples measured on Waters, Agilent, and AB SCIEX quadrupole time-of-flight and Thermo Q-Exactive mass spectrometers. The mass accuracy of matched precursor ions also compared favorably with vendor and commercial tools. Additionally, typical analysis runtimes (∼1-100 ms per MS/MS spectrum) were short enough to enable the practical use of these high-quality signal processing tools for large clinical and research data sets.


Asunto(s)
Péptidos/química , Espectrometría de Masas en Tándem/métodos , Algoritmos , Bases de Datos de Proteínas
16.
J Clin Invest ; 124(11): 5057-73, 2014 11.
Artículo en Inglés | MEDLINE | ID: mdl-25329696

RESUMEN

Osteoclastogenesis requires activation of RANK signaling as well as costimulatory signals from immunoreceptor tyrosine-based activation motif-containing (ITAM-containing) receptors/adaptors, predominantly tyrosine kinase-binding proteins DAP12 and FcRγ, in osteoclast precursors. It is not well understood how costimulatory signals are regulated and integrated with RANK signaling. Here, we found that osteopetrotic bone phenotypes in mice lacking DAP12 or DAP12 and FcRγ are mediated by the transcription factor RBP-J, as deletion of Rbpj in these mice substantially rescued the defects of bone remodeling. Using a TNF-α-induced model of inflammatory bone resorption, we determined that RBP-J deficiency enables TNF-α to induce osteoclast formation and bone resorption in DAP12-deficient animals. Thus, RBP-J imposes a requirement for ITAM-mediated costimulation of RANKL or TNF-α-induced osteoclastogenesis. Mechanistically, RBP-J suppressed induction of key osteoclastogenic factors NFATc1, BLIMP1, and c-FOS by inhibiting ITAM-mediated expression and function of PLCγ2 and activation of downstream calcium-CaMKK/PYK2 signaling. Moreover, RBP-J suppressed Plcg2 expression and downstream calcium oscillations indirectly by a TGF-ß/PLCγ2/calcium axis. Together, our findings indicate that RBP-J suppresses ITAM-mediated costimulation, thereby limiting crosstalk between ITAM and RANK/TNFR signaling and allowing fine tuning of osteoclastogenesis during bone homeostasis and under inflammatory conditions. Furthermore, these data suggest that environmental cues that regulate RBP-J expression/function potentially modulate the requirement for costimulatory signaling for osteoclast differentiation and bone remodeling.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteína de Unión a la Señal Recombinante J de las Inmunoglobulinas/fisiología , Osteoclastos/fisiología , Receptores de IgG/metabolismo , Animales , Resorción Ósea , Señalización del Calcio , Diferenciación Celular , Células Cultivadas , Ratones Noqueados , Factores de Transcripción NFATC/metabolismo , Fosfolipasa C gamma/metabolismo , Factor 1 de Unión al Dominio 1 de Regulación Positiva , Proteínas Proto-Oncogénicas c-fos/metabolismo , Factores de Transcripción/metabolismo , Factor de Necrosis Tumoral alfa/fisiología
17.
Stem Cells Dev ; 23(2): 115-23, 2014 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-24007236

RESUMEN

Human induced pluripotent stem cell (hiPSC) reprogramming possesses enormous potential in stem cell research and disease modeling. Chemical and mechanical signaling has been implicated in the maintenance of pluripotency of hiPSCs, as well as their differentiation pathways toward various lineages. Primary cilia have been shown to play a critical role in mechanochemical signaling across a wide spectrum of cell types. The functions of primary cilia in hiPSCs and their characteristic changes during the reprogramming process remain largely vague. This work focused on understanding how reprogramming affects the mechanical characteristics of primary cilia. Using immunofluorescence imaging assays, we validated the presence of primary cilia on reprogrammed cells. These reprogrammed cells had high expression levels of pluripotency markers, Nanog and Cripto, shown by quantitative polymerase chain reaction assays. We also found high expression of hedgehog signaling proteins Patched1 (Ptch1), Smoothened (Smo), Gli1, and Gli2 in reprogrammed cells. Stimulation of the hedgehog pathway resulted in the concerted movement of Ptch1 out of the cilia and Smo into the cilia, implying that the cilia on iPSCs contain functioning hedgehog machinery. The mean length of primary cilia in reprogrammed cells was shorter than those of parental human fibroblasts. Morphometric analyses revealed that reprogramming resulted in an increase in the curvature of primary cilia from ∼0.015 to 0.064 µm(-1), indicating an underlying approximately fourfold decrease in their rigidity, and a decrease in length of primary cilia from ∼2.38 to ∼1.45 µm. Furthermore, reprogramming resulted in fewer primary cilia displaying kinked geometries.


Asunto(s)
Diferenciación Celular/genética , Reprogramación Celular/genética , Cilios/fisiología , Células Madre Pluripotentes Inducidas/citología , Células Cultivadas , Proteínas Ligadas a GPI/biosíntesis , Proteínas de Homeodominio/biosíntesis , Humanos , Células Madre Pluripotentes Inducidas/fisiología , Péptidos y Proteínas de Señalización Intercelular/biosíntesis , Factores de Transcripción de Tipo Kruppel/biosíntesis , Proteína Homeótica Nanog , Proteínas de Neoplasias/biosíntesis , Proteínas Nucleares/biosíntesis , Receptores Patched , Receptor Patched-1 , Receptores de Superficie Celular/biosíntesis , Receptores Acoplados a Proteínas G/biosíntesis , Transducción de Señal/genética , Receptor Smoothened , Factores de Transcripción/biosíntesis , Proteína con Dedos de Zinc GLI1 , Proteína Gli2 con Dedos de Zinc
18.
J Clin Bioinforma ; 3(1): 3, 2013 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-23343000

RESUMEN

BACKGROUND: The recent introduction of high throughput sequencing technologies into clinical genetics has made it practical to simultaneously sequence many genes. In contrast, previous technologies limited sequencing based tests to only a handful of genes. While the ability to more accurately diagnose inherited diseases is a great benefit it introduces specific challenges. Interpretation of missense mutations continues to be challenging and the number of variants of uncertain significance continues to grow. RESULTS: We leveraged the data available at ARUP Laboratories, a major reference laboratory, for the CFTR gene to explore specific challenges related to variant interpretation, including a focus on understanding ethnic-specific variants and an evaluation of existing databases for clinical interpretation of variants. In this study we analyzed 555 patients representing eight different ethnic groups. We observed 184 different variants, most of which were ethnic group specific. Eighty-five percent of these variants were present in the Cystic Fibrosis Mutation Database, whereas the Human Mutation Database and dbSNP/1000 Genomes had far fewer of the observed variants. Finally, 21 of the variants were novel and we report these variants and their clinical classifications. CONCLUSIONS: Based on our analyses of data from six years of CFTR testing at ARUP Laboratories a more comprehensive, clinical grade database is needed for the accurate interpretation of observed variants. Furthermore, there is a particular need for more and better information regarding variants from individuals of non-Caucasian ethnicity.

19.
J Vet Diagn Invest ; 25(1): 99-106, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23345273

RESUMEN

A novel herpesvirus was detected in sun bears (Helarctos malayanus) with oral squamous cell carcinoma. Five captive sun bears from 4 institutions in the United States presented with oral lesions ranging from erythema and mild erosions to nodular, ulcerated masses. All 5 were diagnosed with squamous cell carcinoma. The tumors were treated with surgical resection but recurrence, local extension, or appearance of new lesions was noted in all cases. Intralesional chemotherapy was administered in 2 cases, and the nonsteroidal anti-inflammatory drug piroxicam was administered in 3 cases. Virus was detected in 4 of the 5 bears' tissue samples using a consensus herpesvirus polymerase chain reaction. Nucleotide sequencing and phylogenetic analysis showed that this herpesvirus is in the subfamily Gammaherpesvirinae and distinct from other known herpesviruses. The association between the herpesvirus and squamous cell carcinoma is unknown. The current study presents a novel gammaherpesvirus within the order Ursidae, with the name Ursid herpesvirus 1 proposed.


Asunto(s)
Carcinoma de Células Escamosas/veterinaria , Gammaherpesvirinae/aislamiento & purificación , Infecciones por Herpesviridae/veterinaria , Neoplasias de la Boca/veterinaria , Infecciones Tumorales por Virus/veterinaria , Ursidae/virología , Secuencia de Aminoácidos , Animales , Antiinflamatorios no Esteroideos/uso terapéutico , Secuencia de Bases , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/terapia , Carcinoma de Células Escamosas/virología , ADN Viral/química , ADN Viral/genética , Femenino , Gammaherpesvirinae/genética , Infecciones por Herpesviridae/patología , Infecciones por Herpesviridae/terapia , Infecciones por Herpesviridae/virología , Histocitoquímica/veterinaria , Masculino , Datos de Secuencia Molecular , Neoplasias de la Boca/patología , Neoplasias de la Boca/terapia , Neoplasias de la Boca/virología , Filogenia , Piroxicam/uso terapéutico , Reacción en Cadena de la Polimerasa/veterinaria , Alineación de Secuencia , Análisis de Secuencia de ADN , Infecciones Tumorales por Virus/patología , Infecciones Tumorales por Virus/terapia , Infecciones Tumorales por Virus/virología
20.
J Proteome Res ; 11(12): 5642-9, 2012 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-23126378

RESUMEN

We investigated the utility of an SPE-MS/MS platform in combination with a modified SISCAPA workflow for chromatography-free MRM analysis of proteotypic peptides in digested human plasma. This combination of SISCAPA and SPE-MS/MS technology allows sensitive, MRM-based quantification of peptides from plasma digests with a sample cycle time of ∼7 s, a 300-fold improvement over typical MRM analyses with analysis times of 30-40 min that use liquid chromatography upstream of MS. The optimized system includes capture and enrichment to near purity of target proteotypic peptides using rigorously selected, high affinity, antipeptide monoclonal antibodies and reduction of background peptides using a novel treatment of magnetic bead immunoadsorbents. Using this method, we have successfully quantitated LPS-binding protein and mesothelin (concentrations of ∼5000 ng/mL and ∼10 ng/mL, respectively) in human plasma. The method eliminates the need for upstream liquid-chromatography and can be multiplexed, thus facilitating quantitative analysis of proteins, including biomarkers, in large sample sets. The method is ideal for high-throughput biomarker validation after affinity enrichment and has the potential for applications in clinical laboratories.


Asunto(s)
Proteínas Sanguíneas/análisis , Ensayos Analíticos de Alto Rendimiento/métodos , Espectrometría de Masas/métodos , Péptidos/sangre , Programas Informáticos , Proteínas de Fase Aguda/análisis , Anticuerpos Monoclonales/química , Afinidad de Anticuerpos , Biomarcadores/sangre , Proteínas Portadoras/análisis , Cromatografía Liquida , Proteínas Ligadas a GPI/sangre , Humanos , Glicoproteínas de Membrana/análisis , Mesotelina , Proteómica/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Factores de Tiempo
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