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1.
Immunity ; 54(6): 1290-1303.e7, 2021 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-34022127

RESUMEN

Dissecting the evolution of memory B cells (MBCs) against SARS-CoV-2 is critical for understanding antibody recall upon secondary exposure. Here, we used single-cell sequencing to profile SARS-CoV-2-reactive B cells in 38 COVID-19 patients. Using oligo-tagged antigen baits, we isolated B cells specific to the SARS-CoV-2 spike, nucleoprotein (NP), open reading frame 8 (ORF8), and endemic human coronavirus (HCoV) spike proteins. SARS-CoV-2 spike-specific cells were enriched in the memory compartment of acutely infected and convalescent patients several months post symptom onset. With severe acute infection, substantial populations of endemic HCoV-reactive antibody-secreting cells were identified and possessed highly mutated variable genes, signifying preexisting immunity. Finally, MBCs exhibited pronounced maturation to NP and ORF8 over time, especially in older patients. Monoclonal antibodies against these targets were non-neutralizing and non-protective in vivo. These findings reveal antibody adaptation to non-neutralizing intracellular antigens during infection, emphasizing the importance of vaccination for inducing neutralizing spike-specific MBCs.


Asunto(s)
Anticuerpos Antivirales/inmunología , Formación de Anticuerpos/inmunología , Linfocitos B/inmunología , COVID-19/inmunología , Interacciones Huésped-Patógeno/inmunología , Epítopos Inmunodominantes/inmunología , SARS-CoV-2/inmunología , Anticuerpos Neutralizantes/inmunología , Formación de Anticuerpos/genética , Linfocitos B/metabolismo , Biología Computacional/métodos , Reacciones Cruzadas/inmunología , Mapeo Epitopo , Femenino , Perfilación de la Expresión Génica , Secuenciación de Nucleótidos de Alto Rendimiento , Interacciones Huésped-Patógeno/genética , Humanos , Epítopos Inmunodominantes/genética , Memoria Inmunológica , Masculino , Pruebas de Neutralización , Análisis de la Célula Individual/métodos , Glicoproteína de la Espiga del Coronavirus/inmunología , Transcriptoma
2.
N Engl J Med ; 380(10): 935-946, 2019 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-30855743

RESUMEN

BACKGROUND: Actinic keratosis is the most frequent premalignant skin disease in the white population. In current guidelines, no clear recommendations are made about which treatment is preferred. METHODS: We investigated the effectiveness of four frequently used field-directed treatments (for multiple lesions in a continuous area). Patients with a clinical diagnosis of five or more actinic keratosis lesions on the head, involving one continuous area of 25 to 100 cm2, were enrolled at four Dutch hospitals. Patients were randomly assigned to treatment with 5% fluorouracil cream, 5% imiquimod cream, methyl aminolevulinate photodynamic therapy (MAL-PDT), or 0.015% ingenol mebutate gel. The primary outcome was the proportion of patients with a reduction of 75% or more in the number of actinic keratosis lesions from baseline to 12 months after the end of treatment. Both a modified intention-to-treat analysis and a per-protocol analysis were performed. RESULTS: A total of 624 patients were included from November 2014 through March 2017. At 12 months after the end of treatment, the cumulative probability of remaining free from treatment failure was significantly higher among patients who received fluorouracil (74.7%; 95% confidence interval [CI], 66.8 to 81.0) than among those who received imiquimod (53.9%; 95% CI, 45.4 to 61.6), MAL-PDT (37.7%; 95% CI, 30.0 to 45.3), or ingenol mebutate (28.9%; 95% CI, 21.8 to 36.3). As compared with fluorouracil, the hazard ratio for treatment failure was 2.03 (95% CI, 1.36 to 3.04) with imiquimod, 2.73 (95% CI, 1.87 to 3.99) with MAL-PDT, and 3.33 (95% CI, 2.29 to 4.85) with ingenol mebutate (P≤0.001 for all comparisons). No unexpected toxic effects were documented. CONCLUSIONS: At 12 months after the end of treatment in patients with multiple actinic keratosis lesions on the head, 5% fluorouracil cream was the most effective of four field-directed treatments. (Funded by the Netherlands Organization for Health Research and Development; ClinicalTrials.gov number, NCT02281682.).


Asunto(s)
Diterpenos/administración & dosificación , Fluorouracilo/administración & dosificación , Imiquimod/administración & dosificación , Queratosis Actínica/tratamiento farmacológico , Fotoquimioterapia , Dermatosis del Cuero Cabelludo/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Ácido Aminolevulínico/análogos & derivados , Ácido Aminolevulínico/uso terapéutico , Diterpenos/efectos adversos , Femenino , Fluorouracilo/efectos adversos , Estudios de Seguimiento , Geles , Humanos , Imiquimod/efectos adversos , Análisis de Intención de Tratar , Masculino , Persona de Mediana Edad , Cooperación del Paciente , Fotoquimioterapia/efectos adversos , Fármacos Fotosensibilizantes/uso terapéutico , Modelos de Riesgos Proporcionales , Método Simple Ciego , Crema para la Piel , Resultado del Tratamiento
3.
J Med Ethics ; 47(1): 7-11, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33046590

RESUMEN

Clinical trials emerged in rapid succession as the COVID-19 pandemic created an unprecedented need for life-saving therapies. Fair and equitable subject selection in clinical trials offering investigational therapies ought to be an urgent moral concern. Subject selection determines the distribution of risks and benefits, and impacts the applicability of the study results for the larger population. While Research Ethics Committees monitor fair subject selection within each trial, no standard oversight exists for subject selection across multiple trials for the same disease. Drawing on the experience of multiple clinical trials at a single academic medical centre in the USA, we posit that concurrent COVID-19 trials are liable to unfair and inequitable subject selection on account of scientific uncertainty, lack of transparency, scarcity and, lastly, structural barriers to equity compounded by implicit bias. To address the critical gap in the current literature and international regulation, we propose new ethical guidelines for research design and conduct that bolsters fair and equitable subject selection. Although the proposed guidelines are tailored to the research design and protocol of concurrent trials in the COVID-19 pandemic, they may have broader relevance to single COVID-19 trials.


Asunto(s)
COVID-19 , Ensayos Clínicos como Asunto/ética , Selección de Paciente/ética , Sesgo , Bioética , Humanos , SARS-CoV-2
4.
J Am Acad Dermatol ; 80(4): 1022-1028, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30582993

RESUMEN

BACKGROUND: There have been concerns that recurrences after noninvasive therapy for basal cell carcinoma (BCC) transform into a "more aggressive" histologic subtype. OBJECTIVE: We sought to evaluate the proportion of patients with a nonsuperficial treatment failure after noninvasive therapy for superficial BCC. METHODS: An observational study was performed using data from a single blind, noninferiority, randomized controlled trial (March 2008-August 2010) with 5-year follow-up in patients with primary superficial BCC treated with methylaminolevulinate-photodynamic therapy, 5-fluorouracil, or imiquimod. Data were used from 166 adults with a histologically confirmed treatment failure. RESULTS: A nonsuperficial subtype was found in 64 of 166 treatment failures (38.6%). Proportions with a more aggressive subtype than the primary tumor were 51.3% (38/74) for early and 28.3% (26/92) for later treatment failures (P = .003). The proportion of more aggressive early failures was significantly lower after imiquimod (26.3%) compared with methylaminolevulinate-photodynamic therapy (54.8%, P = .086) and 5-fluorouracil (66.7%, P = .011). LIMITATIONS: There was limited information on the exact time of occurrence of treatment failures. CONCLUSION: More aggressive treatment failure recurrences after noninvasive therapy for superficial BCC occur most often within the first 3 months posttreatment, probably indicating underdiagnosis of more aggressive components in the primary tumor rather than transformation.


Asunto(s)
Carcinoma Basocelular/tratamiento farmacológico , Carcinoma Basocelular/patología , Fotoquimioterapia , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/patología , Anciano , Ácido Aminolevulínico/análogos & derivados , Ácido Aminolevulínico/uso terapéutico , Antimetabolitos Antineoplásicos/uso terapéutico , Antineoplásicos/uso terapéutico , Estudios de Equivalencia como Asunto , Femenino , Fluorouracilo/uso terapéutico , Humanos , Imiquimod/uso terapéutico , Masculino , Persona de Mediana Edad , Fármacos Fotosensibilizantes/uso terapéutico , Insuficiencia del Tratamiento
5.
Dermatol Surg ; 45(11): 1353-1358, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31274528

RESUMEN

BACKGROUND: Incidence trends of nonmelanoma skin cancer show an increase. Few data have been published about the incidence of Bowen disease (BD). Three previous studies, conducted more than 15 years ago in North America, found large variation in incidence rates in Caucasians, and trends over longer periods have never been studied. OBJECTIVE: To estimate the incidence of BD in a Caucasian population in Northern Europe (Maastricht, the Netherlands) between 2003 and 2013. METHODS: Primary and histologically confirmed BD, diagnosed in Maastricht, the Netherlands, in the years 2003, 2008, and 2013, was retrieved from a pathology database. Age-standardized and sex-specific incidence rates per 100,000 inhabitants were calculated by using the age distribution of the European standard population of 2013. RESULTS: A statistically significant increase in the annual age-standardized incidence rates per 100,000 people was found from 8.1 (95% confidence interval [CI] 3.7-12.5) in 2003 to 68.9 (95% CI 57.2-80.7) in 2013 (p < .001). For women, there was an increase from 7.7/100,000 (95% CI 2.0-13.4) in 2003 to 76.8/100,000 (95% CI 60.2-93.5) in 2013, respectively (p < .001). An increase from 8.8/100,000 (95% CI 1.8-15.9) in 2003 to 59.2/100,000 men (95% CI 42.8-75.6) in 2013 (p < .001) was found. CONCLUSION: These findings suggest an increase in the annual age-standardized incidence rates in BD.


Asunto(s)
Enfermedad de Bowen/epidemiología , Neoplasias Cutáneas/epidemiología , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Países Bajos/epidemiología , Distribución por Sexo , Población Blanca/estadística & datos numéricos
6.
N Engl J Med ; 380(23): 2275-2276, 2019 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-31167065
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