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1.
Mol Microbiol ; 120(5): 723-739, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37800599

RESUMEN

DectiSomes are anti-infective drug-loaded liposomes targeted to pathogenic cells by pathogen receptors including the Dectins. We have previously used C-type lectin (CTL) pathogen receptors Dectin-1, Dectin-2, and DC-SIGN to target DectiSomes to the extracellular oligoglycans surrounding diverse pathogenic fungi and kill them. Dectin-3 (also known as MCL, CLEC4D) is a CTL pathogen receptor whose known cognate ligands are partly distinct from other CTLs. We expressed and purified a truncated Dectin-3 polypeptide (DEC3) comprised of its carbohydrate recognition domain and stalk region. We prepared amphotericin B (AmB)-loaded pegylated liposomes (AmB-LLs) and coated them with this isoform of Dectin-3 (DEC3-AmB-LLs), and we prepared control liposomes coated with bovine serum albumin (BSA-AmB-LLs). DEC3-AmB-LLs bound to the exopolysaccharide matrices of Candida albicans, Rhizopus delemar (formerly known as R. oryzae), and Cryptococcus neoformans from one to several orders of magnitude more strongly than untargeted AmB-LLs or BSA-AmB-LLs. The data from our quantitative fluorescent binding assays were standardized using a CellProfiler program, AreaPipe, that was developed for this purpose. Consistent with enhanced binding, DEC3-AmB-LLs inhibited and/or killed C. albicans and R. delemar more efficiently than control liposomes and significantly reduced the effective dose of AmB. In conclusion, Dectin-3 targeting has the potential to advance our goal of building pan-antifungal DectiSomes.


Asunto(s)
Antifúngicos , Criptococosis , Humanos , Antifúngicos/farmacología , Liposomas/química , Liposomas/farmacología , Anfotericina B/farmacología , Anfotericina B/química , Candida albicans
2.
PLoS Pathog ; 17(7): e1009699, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34293050

RESUMEN

Globally, there are several million individuals with life-threatening invasive fungal diseases such as candidiasis, aspergillosis, cryptococcosis, Pneumocystis pneumonia (PCP), and mucormycosis. The mortality rate for these diseases generally exceeds 40%. Annual medical costs to treat these invasive fungal diseases in the United States exceed several billion dollars. In addition to AIDS patients, the risks of invasive mycoses are increasingly found in immune-impaired individuals or in immunosuppressed patients following stem cell or organ transplant or implantation of medical devices. Current antifungal drug therapies are not meeting the challenge, because (1) at safe doses, they do not provide sufficient fungal clearance to prevent reemergence of infection; (2) most become toxic with extended use; (3) drug-resistant fungal isolates are emerging; and (4) only one new class of antifungal drugs has been approved for clinical use in the last 2 decades. DectiSomes represent a novel design of drug delivery to drastically increase drug efficacy. Antifungals packaged in liposomes are targeted specifically to where the pathogen is, through binding to the fungal cell walls or exopolysaccharide matrices using the carbohydrate recognition domains of pathogen receptors. Relative to untargeted liposomal drug, DectiSomes show order of magnitude increases in the binding to and killing of Candida albicans, Cryptococcus neoformans, and Aspergillus fumigatus in vitro and similarly improved efficacy in mouse models of pulmonary aspergillosis. DectiSomes have the potential to usher in a new antifungal drug treatment paradigm.


Asunto(s)
Antifúngicos/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Micosis/tratamiento farmacológico , Animales , Portadores de Fármacos/administración & dosificación , Humanos , Lectinas Tipo C/metabolismo , Liposomas , Ratones
3.
Antimicrob Agents Chemother ; 66(1): e0146721, 2022 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-34633846

RESUMEN

Candida albicans causes life-threatening disseminated candidiasis. Individuals at greatest risk have weakened immune systems. An outer cell wall, exopolysaccharide matrix, and biofilm rich in oligoglucans and oligomannans help Candida spp. evade host defenses. Even after antifungal treatment, the 1-year mortality rate exceeds 25%. Undoubtedly, there is room to improve drug performance. The mammalian C-type lectin pathogen receptors Dectin-1 and Dectin-2 bind to fungal oligoglucans and oligomannans, respectively. We previously coated amphotericin B-loaded liposomes, AmB-LLs, pegylated analogs of AmBisome, with the ligand binding domains of these two Dectins. DectiSomes, DEC1-AmB-LLs and DEC2-AmB-LLs, showed two distinct patterns of binding to the exopolysaccharide matrix surrounding C. albicans hyphae grown in vitro. Here we showed that DectiSomes were preferentially associated with fungal colonies in the kidneys. In a neutropenic mouse model of candidiasis, DEC1-AmB-LLs and DEC2-AmB-LLs delivering only one dose of 0.2 mg/kg AmB reduced the kidney fungal burden several fold relative to AmB-LLs. DEC1-AmB-LLs and DEC2-AmB-LLs increased the percent of surviving mice 2.5-fold and 8.3-fold, respectively, relative to AmB-LLs. Dectin-2 targeting of anidulafungin loaded liposomes, DEC2-AFG-LLs, and of commercial AmBisome, DEC2-AmBisome, reduced fungal burden in the kidneys several fold over their untargeted counterparts. The data herein suggest that targeting of a variety of antifungal drugs to fungal glycans may achieve lower safer effective doses and improve drug efficacy against a variety of invasive fungal infections.


Asunto(s)
Candidiasis , Liposomas , Animales , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Candida albicans , Candidiasis/microbiología , Liposomas/química , Mamíferos , Ratones , Polisacáridos/farmacología
4.
Sleep Breath ; 25(3): 1641-1653, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33037528

RESUMEN

PURPOSE: Obstructive sleep apnea (OSA) results in systemic intermittent hypoxia. By one model, hypoxic stress signaling in OSA patients alters the levels of inflammatory soluble cytokines TNF and IL6, damages the blood brain barrier, and activates microglial targeting of neuronal cell death to increase the risk of neurodegenerative disorders and other diseases. However, it is not yet clear if OSA significantly alters the levels of the soluble isoforms of TNF receptors TNFR1 and TNFR2 and IL6 receptor (IL6R) and co-receptor gp130, which have the potential to modulate TNF and IL6 signaling. METHODS: Picogram per milliliter levels of the soluble isoforms of these four cytokine receptors were estimated in OSA patients, in OSA patients receiving airways therapy, and in healthy control subjects. Triplicate samples were examined using Bio-Plex fluorescent bead microfluidic technology. The statistical significance of cytokine data was estimated using the nonparametric Wilcoxon rank-sum test. The clustering of these high-dimensional data was visualized using t-distributed stochastic neighbor embedding (t-SNE). RESULTS: OSA patients had significant twofold to sevenfold reductions in the soluble serum isoforms of all four cytokine receptors, gp130, IL6R, TNFR1, and TNFR2, as compared with control individuals (p = 1.8 × 10-13 to 4 × 10-8). Relative to untreated OSA patients, airways therapy of OSA patients had significantly higher levels of gp130 (p = 2.8 × 10-13), IL6R (p = 1.1 × 10-9), TNFR1 (p = 2.5 × 10-10), and TNFR2 (p = 5.7 × 10-9), levels indistinguishable from controls (p = 0.29 to 0.95). The data for most airway-treated patients clustered with healthy controls, but the data for a few airway-treated patients clustered with apneic patients. CONCLUSIONS: Patients with OSA have aberrantly low levels of four soluble cytokine receptors associated with neurodegenerative disease, gp130, IL6R, TNFR1, and TNFR2. Most OSA patients receiving airways therapy have receptor levels indistinguishable from healthy controls, suggesting a chronic intermittent hypoxia may be one of the factors contributing to low receptor levels in untreated OSA patients.


Asunto(s)
Presión de las Vías Aéreas Positiva Contínua , Enfermedades Neurodegenerativas/epidemiología , Receptores de Citocinas/sangre , Apnea Obstructiva del Sueño/terapia , Adulto , Anciano , Receptor gp130 de Citocinas/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Receptores de Interleucina-6/sangre , Receptores Tipo I de Factores de Necrosis Tumoral/sangre , Receptores Tipo II del Factor de Necrosis Tumoral/sangre , Apnea Obstructiva del Sueño/sangre , Resultado del Tratamiento
5.
Clin Immunol ; 221: 108601, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33017651

RESUMEN

Obstructive Sleep Apnea (OSA) damages the health of 35% of adult Americans. Disordered sleep results in increased risk of several autoimmune disorders, but the molecular links to autoimmunity are poorly understood. Herein, we identified four cytokines associated with autoimmune disease, whose median serum levels were significantly different for OSA patients receiving airways therapy, from the levels in untreated OSA patients, APRIL (5.2-fold lower, p = 3.5 × 10-11), CD30 (1.6-fold higher, p = 7.7 × 10-5), IFN-Alpha-2 (2.9-fold higher, p = 9.6 × 10-14) and IL-2 (1.9-fold higher, p = 0.0003). Cytokine levels in airways treated patients were similar to the levels in control subjects. t-SNE and UMAP analysis of these high dimensional patient cytokine data identified only two groups, suggesting a similar global response for all four cytokines to airways therapy. Our findings suggest the levels of these four cytokines may be altered by disordered sleep and perhaps by chronic hypoxia. Therapeutic options are discussed.


Asunto(s)
Enfermedades Autoinmunes/terapia , Presión de las Vías Aéreas Positiva Contínua , Citocinas/inmunología , Apnea Obstructiva del Sueño/terapia , Adulto , Anciano , Enfermedades Autoinmunes/sangre , Enfermedades Autoinmunes/inmunología , Citocinas/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Apnea Obstructiva del Sueño/sangre , Apnea Obstructiva del Sueño/inmunología
6.
Plant J ; 94(2): 215-231, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29513366

RESUMEN

Cell differentiation is driven by changes in the activity of transcription factors (TFs) and subsequent alterations in transcription. To study this process, differences in TF binding between cell types can be deduced by probing chromatin accessibility. We used cell type-specific nuclear purification followed by the assay for transposase-accessible chromatin (ATAC-seq) to delineate differences in chromatin accessibility and TF regulatory networks between stem cells of the shoot apical meristem (SAM) and differentiated leaf mesophyll cells in Arabidopsis thaliana. Chromatin accessibility profiles of SAM stem cells and leaf mesophyll cells were very similar at a qualitative level, yet thousands of regions having quantitatively different chromatin accessibility were also identified. Analysis of the genomic regions preferentially accessible in each cell type identified hundreds of overrepresented TF-binding motifs, highlighting sets of TFs that are probably important for each cell type. Within these sets, we found evidence for extensive co-regulation of target genes by multiple TFs that are preferentially expressed in each cell type. Interestingly, the TFs within each of these cell type-enriched sets also showed evidence of extensively co-regulating each other. We further found that preferentially accessible chromatin regions in mesophyll cells tended to also be substantially accessible in the stem cells, whereas the converse was not true. This observation suggests that the generally higher accessibility of regulatory elements in stem cells might contribute to their developmental plasticity. This work demonstrates the utility of cell type-specific chromatin accessibility profiling for the rapid development of testable models of regulatory control differences between cell types.


Asunto(s)
Proteínas de Arabidopsis/fisiología , Arabidopsis/metabolismo , Cromatina/metabolismo , Células del Mesófilo/metabolismo , Células Madre/metabolismo , Factores de Transcripción/fisiología , Arabidopsis/citología , Regulación de la Expresión Génica de las Plantas , Meristema/citología , Meristema/metabolismo , Hojas de la Planta/citología , Hojas de la Planta/metabolismo , Brotes de la Planta/citología , Brotes de la Planta/metabolismo
7.
Biol Blood Marrow Transplant ; 24(1): 142-149, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28951193

RESUMEN

Ex vivo CD34+ selection before allogeneic hematopoietic stem cell transplantation (allo-HCT) reduces graft-versus-host disease without increasing relapse but usually requires myeloablative conditioning. We aimed to identify toxicity patterns in older patients and the association with overall survival (OS) and nonrelapse mortality (NRM). We conducted a retrospective analysis of 200 patients who underwent CD34+ selection allo-HCT using the ClinicMACS® system between 2006 and 2012. All grade 3 to 5 toxicities by CTCAE v4.0 were collected. Eighty patients aged ≥ 60 years with a median age of 64 (range, 60 to 73) were compared with 120 patients aged < 60 years. Median follow-up in survivors was 48.2 months. OS and NRM were similar between ages ≥ 60 and <60, with 1-year OS 70% versus 78% (P = .07) and 1-year NRM 23% versus 13% (P = .38), respectively. In patients aged ≥ 60 the most common toxicities by day 100 were metabolic, with a cumulative incidence of 88% (95% CI, 78% to 93%), infectious 84% (95% CI, 73% to 90%), hematologic 80% (95% CI, 69% to 87%), oral/gastrointestinal (GI) 48% (95% CI, 36% to 58%), cardiovascular (CV) 35% (95% CI, 25% to 46%), and hepatic 25% (95% CI, 16% to 35%). Patients aged ≥ 60 had a higher risk of neurologic (HR, 2.63 [95% CI, 1.45 to 4.78]; P = .001) and CV (HR, 1.65 [95% CI, 1.04 to 2.63]; P = .03) toxicities but a lower risk of oral/GI (HR, .58 [95% CI, .41 to .83]; P = .003) compared with those aged < 60. CV, hepatic, neurologic, pulmonary, and renal toxicities remained independent risk factors for the risk of death and NRM in separate multivariate models adjusting for age and hematopoietic cell transplantation-specific comorbidity index. Overall, the toxicity of a more intense regimen is potentially balanced by the absence of toxicity related to methotrexate and calcineurin inhibitors in older patients. Prospective study of toxicities after allo-HCT in older patients is essential.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas/efectos adversos , Efectos Adversos a Largo Plazo , Adulto , Factores de Edad , Anciano , Antígenos CD34/sangre , Femenino , Trasplante de Células Madre Hematopoyéticas/métodos , Trasplante de Células Madre Hematopoyéticas/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Análisis de Supervivencia , Trasplante Homólogo/efectos adversos , Trasplante Homólogo/mortalidad
8.
Biol Blood Marrow Transplant ; 24(1): 133-141, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28870777

RESUMEN

The late adverse events in long-term survivors after myeloablative-conditioned allogeneic hematopoietic cell transplantation (HCT) with ex vivo CD34+ cell selection are not well characterized. Using the National Cancer Institute's Common Terminology Criteria for Adverse Events, version 4.0, we assessed all grade ≥3 toxicities from the start of conditioning to the date of death, relapse, or last contact in 131 patients who survived >1 year post-HCT, identifying 285 individual toxicities among 17 organ-based toxicity groups. Pretransplantation absolute lymphocyte count >.5 K/µL and serum albumin >4.0 g/dL were associated with a reduced risk of toxicities, death, and nonrelapse mortality (NRM), whereas serum ferritin >1000 ng/mL was associated with an increased risk of toxicities and NRM after 1 year. An HCT Comorbidity Index (HCT-CI) score ≥3 was associated with an increased risk of all-cause death and NRM, but was not associated with a specific increased toxicity risk after 1 year. Patients who incurred more than the median number of toxicities (n = 7) among all patients within the first year subsequently had an increased risk of hematologic, infectious, and metabolic toxicities, as well as an increased risk of NRM and inferior 4-year overall survival (OS) (67% versus 86%; P = .003) after the 1-year landmark. The development of grade II-IV acute graft-versus-host disease (GVHD) within the first year was associated with incurring >7 toxicities within the first year (P = .016), and also with an increased risk of all-cause death and NRM after 1 year. In multivariate models, cardiovascular, hematologic, hepatic, infectious, metabolic, neurologic, and pulmonary toxicities incurred after 1 year were independently associated with increased risk of death and NRM when adjusting for both HCT-CI and grade II-IV acute GVHD within the first year. One-year survivors of ex vivo CD34+ selection had a favorable 4-year OS of 77%, although the development of grade ≥3 toxicities after the first year was associated with poorer outcomes, emphasizing the fundamental importance of improving survivorship efforts that may improve long-term toxicity burden and outcome.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas/efectos adversos , Efectos Adversos a Largo Plazo , Sobrevivientes , Adulto , Anciano , Femenino , Enfermedad Injerto contra Huésped/mortalidad , Trasplante de Células Madre Hematopoyéticas/métodos , Humanos , Masculino , Persona de Mediana Edad , Agonistas Mieloablativos/efectos adversos , Factores de Riesgo , Análisis de Supervivencia , Acondicionamiento Pretrasplante/efectos adversos , Trasplante Homólogo/efectos adversos , Trasplante Homólogo/métodos
9.
Biol Blood Marrow Transplant ; 23(11): 2004-2011, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28733264

RESUMEN

Factors that impact first-year morbidity and mortality in adults undergoing myeloablative allogeneic hematopoietic cell transplantation with ex vivo CD34+ selection have not been previously reported. We assessed all toxicities ≥ grade 3 from the start of conditioning to date of death, relapse, or last contact in 200 patients during the first year after transplantation, identifying 1885 individual toxicities among 17 organ-based toxicity groups. The most prevalent toxicities in the first year were of infectious, metabolic, hematologic, oral/gastrointestinal, hepatic, cardiac, and pulmonary etiologies. Renal complications were minimal. Grades II to IV and III and IV acute GVHD at day 100 were 11.5% and 3%, respectively. In separate multivariate models, cardiovascular, hematologic, hepatic, neurologic, pulmonary, and renal toxicities negatively impacted nonrelapse mortality (NRM) and overall survival during the first year. A higher-than-targeted busulfan level, patient cytomegalovirus seropositivity, and an Hematopoietic Cell Transplantation-Specific Comorbidity Index of ≥3 were associated with increased risk of NRM and all-cause death. Ex vivo CD34+ selection had a favorable 1-year OS of 75% and NRM of 17% and a low incidence of sinusoidal obstruction syndrome. These data establish a benchmark to focus efforts in reducing toxicity burden while improving patient outcomes.


Asunto(s)
Antígenos CD34/metabolismo , Neoplasias Hematológicas/terapia , Trasplante de Células Madre Hematopoyéticas/métodos , Acondicionamiento Pretrasplante/métodos , Trasplante Homólogo/métodos , Adulto , Anciano , Femenino , Neoplasias Hematológicas/patología , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Adulto Joven
10.
Biol Blood Marrow Transplant ; 23(3): 452-458, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28017734

RESUMEN

Ex vivo CD34+-selected T cell depletion (TCD) has been developed as a strategy to reduce the incidence of graft-versus-host disease (GVHD) after allogeneic (allo) hematopoietic stem cell transplantation (HSCT). Clinical characteristics, treatment responses, and outcomes of patients developing acute (aGVHD) and chronic GVHD (cGVHD) after TCD allo-HSCT have not been well established. We evaluated 241 consecutive patients (median age, 57 years) with acute leukemia (n = 191, 79%) or myelodysplastic syndrome (MDS) (n = 50, 21%) undergoing CD34+-selected TCD allo-HSCT without post-HCST immunosuppression in a single institution. Cumulative incidences of grades II-IV and III-IV aGVHD at 180 days were 16% (95% confidence interval [CI], 12 to 21) and 5% (95% CI, 3 to 9), respectively. The skin was the most frequent organ involved, followed by the gastrointestinal tract. Patients were treated with topical corticosteroids, poorly absorbed corticosteroids (budesonide), and/or systemic corticosteroids. The overall day 28 treatment response was high at 82%. The cumulative incidence of any cGVHD at 3 years was 5% (95% CI, 3 to 9), with a median time of onset of 256 days (range, 95 to 1645). The 3-year transplant-related mortality, relapse, overall survival, and disease-free survival were 24% (95% CI, 18 to 30), 22% (95% CI, 17 to 27), 57% (95% CI, 50 to 64), and 54% (95% CI, 47 to 61), respectively. The 1-year and 3-year probabilities of cGVHD-free/relapse-free survival were 65% (95% CI, 59 to 71) and 52% (95% CI, 45 to 59), respectively. Our findings support the use of ex vivo CD34+-selected TCD allograft as a calcineurin inhibitor-free intervention for the prevention of GVHD in patients with acute leukemia and MDS.


Asunto(s)
Enfermedad Injerto contra Huésped/etiología , Trasplante de Células Madre Hematopoyéticas/métodos , Leucemia/terapia , Depleción Linfocítica/métodos , Síndromes Mielodisplásicos/terapia , Enfermedad Aguda , Adulto , Anciano , Antígenos CD34 , Femenino , Enfermedad Injerto contra Huésped/patología , Enfermedad Injerto contra Huésped/prevención & control , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Trasplante de Células Madre Hematopoyéticas/mortalidad , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Trasplante de Células Madre de Sangre Periférica/efectos adversos , Trasplante de Células Madre de Sangre Periférica/métodos , Trasplante de Células Madre de Sangre Periférica/mortalidad , Análisis de Supervivencia , Trasplante Homólogo , Resultado del Tratamiento , Adulto Joven
11.
Int J Vitam Nutr Res ; 87(5-6): 271-278, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30499755

RESUMEN

Folate, a water-soluble vitamin, is a key source of one-carbon groups for DNA methylation, but studies of the DNA methylation response to supplemental folic acid yield inconsistent results. These studies are commonly conducted using whole blood, which contains a mixed population of white blood cells that have been shown to confound results. The objective of this study was to determine if CD16+ neutrophils may provide more specific data than whole blood for identifying DNA methylation response to chronic folic acid supplementation. The study was performed in normal weight (BMI 18.5 - 24.9 kg/m2) women (18 - 35 y; n = 12), with blood samples taken before and after 8 weeks of folic acid supplementation at 800 µg/day. DNA methylation patterns from whole blood and isolated CD16+ neutrophils were measured across >485,000 CpG sites throughout the genome using the Infinium HumanMethylation450 BeadChip. Over the course of the 8-week supplementation, 6746 and 7513 CpG sites changed (p < 0.05) in whole blood and CD16+ neutrophils, respectively. DNA methylation decreased in 68.4% (whole blood) and 71.8% (CD16+ neutrophils) of these sites. There were only 182 CpG sites that changed in both the whole blood and CD16+ neutrophils, 139 of which changed in the same direction. These results suggest that the genome-wide DNA methylation response to chronic folic acid supplementation is different between whole blood and CD16+ neutrophils and that a single white blood cell type may function as a more specific epigenetic reporter of folate status than whole blood.

12.
Blood ; 124(19): 2905-12, 2014 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-25185264

RESUMEN

We investigated the unit characteristics associated with engraftment after double-unit cord blood (CB) transplantation (dCBT) and whether these could be reliably identified during unit selection. Cumulative incidence of neutrophil engraftment in 129 myeloablative dCBT recipients was 95% (95% confidence interval: 90-98%). When precryopreservation characteristics were analyzed, the dominant unit CD34(+) cell dose was the only characteristic independently associated with engraftment (hazard ratio, 1.43; P = .002). When postthaw characteristics were also included, only dominant unit infused viable CD34(+) cell dose independently predicted engraftment (hazard ratio, 1.95; P < .001). We then examined the determinants of infused viable CD34(+) cell dose (precryopreservation count, postthaw recovery, and postthaw viability) in 402 units thawed at our center. This revealed close correlation between precryopreservation and postthaw CD34(+) cell counts (r(2) = 0.73). Median CD34(+) cell recovery was 101%, although it ranged from 12% to 1480%. Notably, units from non-Netcord Foundation for the Accreditation of Cellular Therapy (Netcord-FACT)-accredited banks were more likely to have low recovery (P < .001). Furthermore, although median postthaw CD34(+) cell viability was 92%, 33 (8%) units had <75% viable CD34(+) cells. Units from non-Netcord-FACT-accredited banks and units with cryovolumes other than 24.5 to 26.0 mL were more likely to have poor postthaw viability. Precryopreservation CD34(+) cell dose and banking practices should be incorporated into CB unit selection.


Asunto(s)
Almacenamiento de Sangre/métodos , Trasplante de Células Madre de Sangre del Cordón Umbilical/métodos , Neoplasias Hematológicas/terapia , Trasplante de Células Madre Hematopoyéticas/métodos , Neutrófilos/trasplante , Adolescente , Adulto , Anciano , Antígenos CD34/metabolismo , Biomarcadores/metabolismo , Conservación de la Sangre/métodos , Separación Celular/métodos , Niño , Preescolar , Criopreservación/métodos , Supervivencia de Injerto , Humanos , Lactante , Persona de Mediana Edad , Adulto Joven
13.
Transfusion ; 56(5): 1008-12, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26919388

RESUMEN

Graft-versus-host disease remains the most important source of morbidity and mortality associated with allogeneic stem cell transplantation. The implementation of hematopoietic progenitor cell (HPC) selection is employed by some stem cell processing facilities to mitigate this complication. Current cell selection methods include reducing the number of unwanted T cells (negative selection) and/or enriching CD34+ hematopoietic stem/progenitors (positive selection) using immunomagnetic beads subjected to magnetic fields within columns to separate out targeted cells. Unwanted side effects of cell selection as a result of T-cell reduction are primary graft failure, increased infection rates, delayed immune reconstitution, possible disease relapse, and posttransplant lymphoproliferative disease. The Miltenyi CliniMACS cell isolation system is the only device currently approved for clinical use by the Food and Drug Administration. It uses magnetic microbeads conjugated with a high-affinity anti-CD34 monoclonal antibody capable of binding to HPCs in marrow, peripheral blood, or umbilical cord blood products. The system results in significantly improved CD34+ cell recoveries (50%-100%) and consistent 3-log CD3+ T-cell reductions compared to previous generations of CD34+ cell selection procedures. In this article, the CliniMACS procedure is described in greater detail and the authors provide useful insight into modifications of the system. Successful implementation of cell selection procedures can have a significant positive clinical effect by greatly increasing the pool of donors for recipients requiring transplants. However, before a program implements cell selection techniques, it is important to consider the time and financial resources required to properly and safely perform these procedures.


Asunto(s)
Antígenos CD34/inmunología , Células Madre Hematopoyéticas/citología , Antígenos CD34/aislamiento & purificación , Enfermedad Injerto contra Huésped/etiología , Enfermedad Injerto contra Huésped/prevención & control , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Trasplante de Células Madre Hematopoyéticas/mortalidad , Humanos , Separación Inmunomagnética
14.
Transfusion ; 56(2): 528-32, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26395285

RESUMEN

BACKGROUND: Allogeneic hematopoietic stem cell donor selection is based primarily on human leukocyte antigen degree of match and it often occurs without regard to the red blood cell (RBC) compatibility between donor and recipient. When major ABO-mismatched grafts are infused, it is imperative that an accurate determination of the incompatible RBC content is made to ensure that the product is safe for infusion. RBC content determination requires the hematocrit (Hct) parameter which can be obtained via manual (directly measured) or automated (calculated) methods. STUDY DESIGN AND METHODS: Ninety-seven apheresis hematopoietic progenitor grafts were assessed for Hct by manual testing and by four commercially available automated hematology analyzer instruments. A clinical model was developed to assess the frequency of unnecessary RBC reductions or alteration in standard infusion practice. RESULTS: Significant (p < 0.001) differences were observed where the manual Hct value was markedly lower than automated Hct values. At stringent incompatible RBC threshold of 10 mL, the number of preventable RBC reduction procedures ranged from 18% to 69%. CONCLUSION: Accurate determination of RBC content of hematopoietic progenitor grafts is essential for patient safety. Despite the rapidity and convenience offered by automated Hct methods, they significantly overestimate the incompatible RBC content of grafts, which may trigger unnecessary RBC reduction procedures or split infusions. In products where automated Hct methods indicate excessive amounts of incompatible RBCs are present, we advise the performance of confirmatory testing with a manual Hct method to ensure that the automated Hct value is not a false positive.


Asunto(s)
Sistema del Grupo Sanguíneo ABO , Eliminación de Componentes Sanguíneos/métodos , Incompatibilidad de Grupos Sanguíneos , Eritrocitos , Células Madre Hematopoyéticas/citología , Modelos Biológicos , Femenino , Hematócrito/métodos , Células Madre Hematopoyéticas/metabolismo , Humanos , Masculino
15.
BMC Plant Biol ; 15: 177, 2015 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-26160044

RESUMEN

BACKGROUND: The actin cytoskeleton is involved in an array of integral structural and developmental processes throughout the cell. One of actin's best-studied binding partners is the small ubiquitously expressed protein, profilin. Arabidopsis thaliana is known to encode a family of five profilin sequence variants: three vegetative (also constitutive) profilins that are predominantly expressed in all vegetative tissues and ovules, and two reproductive profilins that are specifically expressed in pollen. This paper analyzes the roles of the three vegetative profilin members, PRF1, PRF2, and PRF3, in plant cell and organ development. RESULTS: Using a collection of knockout or severe knockdown T-DNA single mutants, we found that defects in each of the three variants gave rise to specific developmental deficiencies. Plants lacking PRF1 or PRF2 had defects in rosette leaf morphology and inflorescence stature, while those lacking PRF3 led to plants with slightly elongated petioles. To further examine these effects, double mutants and double and triple gene-silenced RNAi epialleles were created. These plants displayed significantly compounded developmental defects, as well as distinct lateral root growth morphological phenotypes. CONCLUSION: These results suggest that having at least one vegetative profilin gene is essential to viability. Evidence is presented that combinations of independent function, quantitative genetic effects, and functional redundancy have preserved the three vegetative profilin genes in the Arabidopsis lineage.


Asunto(s)
Proteínas de Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Arabidopsis/genética , ADN Bacteriano/genética , ADN de Plantas/genética , Organogénesis de las Plantas , Arabidopsis/citología , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , ADN Bacteriano/metabolismo , ADN de Plantas/metabolismo , Técnicas de Silenciamiento del Gen , Mutación , Fenotipo , Profilinas/genética , Profilinas/metabolismo , Interferencia de ARN
16.
BMC Neurosci ; 16: 51, 2015 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-26260473

RESUMEN

BACKGROUND: Recent evidence identifies the hippocampus, a brain structure commonly associated with learning and memory, as key to the regulation of food intake and the development and consequences of obesity. Intake of a high fat diet (HFD) results in altered consumptive behavior, hippocampal damage, and cognitive deficits. While many studies report the effects of HFD after chronic consumption and in the instance of obesity, few examine the events that occur following acute HFD consumption. In this study, male rats were fed either a control diet (10% fat by kcal) or HFD (45% fat by kcal) for 72 h. At the end of the 72-h period, serum and tissues were collected and weighed. Brains were rapidly frozen or formalin-fixed in preparation for qRT-PCR or immunohistochemistry, respectively. RESULTS: Acute intake of HFD resulted in higher serum levels of leptin and cholesterol, with no significant changes in final body weight or adipose tissue mass. In the dorsal hippocampus, transcription of the neuroprotective peptide galanin was significantly upregulated along with a trend for an increase in brain-derived neurotrophic factor and histone deacetylase 2 in the rats fed HFD. In the ventral hippocampus, there was a significant increase in histone deacetylase 4 and a decrease in galanin receptor 1 in this group. Results from immunohistochemistry validate strong presence of the galanin peptide in the CA1/CA2 region of the dorsal hippocampus. CONCLUSIONS: These results provide evidence for a distinct response in specific functional regions of the hippocampus following acute HFD intake.


Asunto(s)
Dieta Alta en Grasa/efectos adversos , Galanina/metabolismo , Hipocampo/metabolismo , Tejido Adiposo/patología , Tejido Adiposo/fisiología , Animales , Peso Corporal/fisiología , Colesterol/sangre , Ingestión de Alimentos/fisiología , Ensayo de Inmunoadsorción Enzimática , Expresión Génica , Inmunohistoquímica , Leptina/sangre , Masculino , Tamaño de los Órganos , Ratas Long-Evans , Reacción en Cadena en Tiempo Real de la Polimerasa , Factores de Tiempo
17.
Plant Cell ; 24(5): 2041-57, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22589468

RESUMEN

Actin is an essential multifunctional protein encoded by two distinct ancient classes of genes in animals (cytoplasmic and muscle) and plants (vegetative and reproductive). The prevailing view is that each class of actin variants is functionally distinct. However, we propose that the vegetative plant and cytoplasmic animal variants have conserved functional competence for spatial development inherited from an ancestral protist actin sequence. To test this idea, we ectopically expressed animal and protist actins in Arabidopsis thaliana double vegetative actin mutants that are dramatically altered in cell and organ morphologies. We found that expression of cytoplasmic actins from humans and even a highly divergent invertebrate Ciona intestinalis qualitatively and quantitatively suppressed the root cell polarity and organ defects of act8 act7 mutants and moderately suppressed the root-hairless phenotype of act2 act8 mutants. By contrast, human muscle actins were unable to support prominently any aspect of plant development. Furthermore, actins from three protists representing Choanozoa, Archamoeba, and green algae efficiently suppressed all the phenotypes of both the plant mutants. Remarkably, these data imply that actin's competence to carry out a complex suite of processes essential for multicellular development was already fully developed in single-celled protists and evolved nonprogressively from protists to plants and animals.


Asunto(s)
Proteínas de Arabidopsis/clasificación , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Animales , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Archamoebae/genética , Archamoebae/metabolismo , Chlorophyta/genética , Chlorophyta/metabolismo , Coanoflagelados/genética , Coanoflagelados/metabolismo , Ciona intestinalis/genética , Ciona intestinalis/metabolismo , Filogenia
18.
J Immunol ; 190(6): 2966-75, 2013 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-23408834

RESUMEN

Epigenetic changes play important roles in carcinogenesis and influence initial steps in neoplastic transformation by altering genome stability and regulating gene expression. To characterize epigenomic changes during the transformation of normal plasma cells to myeloma, we modified the HpaII tiny fragment enrichment by ligation-mediated PCR assay to work with small numbers of purified primary marrow plasma cells. The nano-HpaII tiny fragment enrichment by ligation-mediated PCR assay was used to analyze the methylome of CD138(+) cells from 56 subjects representing premalignant (monoclonal gammopathy of uncertain significance), early, and advanced stages of myeloma, as well as healthy controls. Plasma cells from premalignant and early stages of myeloma were characterized by striking, widespread hypomethylation. Gene-specific hypermethylation was seen to occur in the advanced stages, and cell lines representative of relapsed cases were found to be sensitive to decitabine. Aberrant demethylation in monoclonal gammopathy of uncertain significance occurred primarily in CpG islands, whereas differentially methylated loci in cases of myeloma occurred predominantly outside of CpG islands and affected distinct sets of gene pathways, demonstrating qualitative epigenetic differences between premalignant and malignant stages. Examination of the methylation machinery revealed that the methyltransferase, DNMT3A, was aberrantly hypermethylated and underexpressed, but not mutated in myeloma. DNMT3A underexpression was also associated with adverse overall survival in a large cohort of patients, providing insights into genesis of hypomethylation in myeloma. These results demonstrate widespread, stage-specific epigenetic changes during myelomagenesis and suggest that early demethylation can be a potential contributor to genome instability seen in myeloma. We also identify DNMT3A expression as a novel prognostic biomarker and suggest that relapsed cases can be therapeutically targeted by hypomethylating agents.


Asunto(s)
Transformación Celular Neoplásica/inmunología , Metilación de ADN/genética , Metilación de ADN/inmunología , Mieloma Múltiple/genética , Mieloma Múltiple/inmunología , Transformación Celular Neoplásica/genética , Estudios de Cohortes , Diagnóstico Precoz , Regulación Neoplásica de la Expresión Génica/inmunología , Humanos , Mieloma Múltiple/patología , Estadificación de Neoplasias , Reacción en Cadena de la Polimerasa , Recurrencia , Inducción de Remisión , Reproducibilidad de los Resultados , Sindecano-1/biosíntesis , Sindecano-1/genética , Células Tumorales Cultivadas
19.
Biol Blood Marrow Transplant ; 20(4): 490-4, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24361912

RESUMEN

Washing cord blood (CB) grafts involves product manipulation and may result in cell loss. We investigated double-unit CB transplantation (CBT) using red blood cell (RBC)-depleted units diluted with albumin-dextran in patients with hematologic malignancies. One-hundred thirty-six patients (median age, 43 years; range, 4 to 71; median weight, 69 kilograms (kg); range, 24 to 111) underwent transplantation with a 4/6 to 6/6 HLA-matched graft. Patients ≤ 20 kg were excluded, as they only received washed units. Units were diluted a median of 8 fold to a median volume of 200 mL/unit. The median infused total nucleated cell doses were 2.7 (larger unit) and 2.0 (smaller unit) x 10(7)/kg, respectively, and the median post-thaw recovery was 86%. Units were infused consecutively (median, 45 minutes/unit). While only 17 patients (13%) had no infusion reactions, reactions in the remaining 119 patients were almost exclusively mild-moderate (by CTCAE v4 criteria 12 grade 1, 43 grade 2, 63 grade 3) with only 1 patient (< 1%) having a severe (grade 4) reaction. Moreover, most were easily treated. Grade 2 to 3 hypertension was the most common in 101 (74%) patients. The cumulative incidence of sustained donor-derived neutrophil engraftment was high: 95% in myeloablative and 94% in nonmyeloablative CBT recipients. With appropriate supportive care, double-unit CBT with RBC-depleted grafts infused after albumin-dextran dilution is safe with high rates of engraftment in patients > 20 kg.


Asunto(s)
Trasplante de Células Madre de Sangre del Cordón Umbilical/métodos , Supervivencia de Injerto , Neoplasias Hematológicas/terapia , Acondicionamiento Pretrasplante , Adolescente , Adulto , Anciano , Niño , Preescolar , Dextranos/administración & dosificación , Femenino , Antígenos HLA/inmunología , Neoplasias Hematológicas/inmunología , Neoplasias Hematológicas/patología , Prueba de Histocompatibilidad , Humanos , Masculino , Persona de Mediana Edad , Agonistas Mieloablativos/uso terapéutico , Vehículos Farmacéuticos/administración & dosificación , Estudios Retrospectivos , Albúmina Sérica/administración & dosificación , Resultado del Tratamiento
20.
Plant Cell ; 23(10): 3711-26, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22010035

RESUMEN

Actin filament arrays are constantly remodeled as the needs of cells change as well as during responses to biotic and abiotic stimuli. Previous studies demonstrate that many single actin filaments in the cortical array of living Arabidopsis thaliana epidermal cells undergo stochastic dynamics, a combination of rapid growth balanced by disassembly from prolific severing activity. Filament turnover and dynamics are well understood from in vitro biochemical analyses and simple reconstituted systems. However, the identification in living cells of the molecular players involved in controlling actin dynamics awaits the use of model systems, especially ones where the power of genetics can be combined with imaging of individual actin filaments at high spatial and temporal resolution. Here, we test the hypothesis that actin depolymerizing factor (ADF)/cofilin contributes to stochastic filament severing and facilitates actin turnover. A knockout mutant for Arabidopsis ADF4 has longer hypocotyls and epidermal cells when compared with wild-type seedlings. This correlates with a change in actin filament architecture; cytoskeletal arrays in adf4 cells are significantly more bundled and less dense than in wild-type cells. Several parameters of single actin filament turnover are also altered. Notably, adf4 mutant cells have a 2.5-fold reduced severing frequency as well as significantly increased actin filament lengths and lifetimes. Thus, we provide evidence that ADF4 contributes to the stochastic dynamic turnover of actin filaments in plant cells.


Asunto(s)
Citoesqueleto de Actina/metabolismo , Factores Despolimerizantes de la Actina/metabolismo , Actinas/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Citoesqueleto de Actina/ultraestructura , Factores Despolimerizantes de la Actina/genética , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Arabidopsis/ultraestructura , Proteínas de Arabidopsis/genética , Expresión Génica , Técnicas de Inactivación de Genes , Hipocótilo/genética , Hipocótilo/crecimiento & desarrollo , Hipocótilo/metabolismo , Hipocótilo/ultraestructura , Familia de Multigenes , Mutación , Fenotipo , Epidermis de la Planta/genética , Epidermis de la Planta/crecimiento & desarrollo , Epidermis de la Planta/metabolismo , Epidermis de la Planta/ultraestructura , Plantas Modificadas Genéticamente , Proteínas Recombinantes , Plantones/genética , Plantones/crecimiento & desarrollo , Plantones/metabolismo , Plantones/ultraestructura , Procesos Estocásticos , Factores de Tiempo
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