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1.
N Engl J Med ; 385(27): 2531-2543, 2021 12 30.
Artículo en Inglés | MEDLINE | ID: mdl-34965338

RESUMEN

BACKGROUND: Children with human immunodeficiency virus type 1 (HIV-1) infection have limited options for effective antiretroviral treatment (ART). METHODS: We conducted an open-label, randomized, noninferiority trial comparing three-drug ART based on the HIV integrase inhibitor dolutegravir with standard care (non-dolutegravir-based ART) in children and adolescents starting first- or second-line ART. The primary end point was the proportion of participants with virologic or clinical treatment failure by 96 weeks, as estimated by the Kaplan-Meier method. Safety was assessed. RESULTS: From September 2016 through June 2018, a total of 707 children and adolescents who weighed at least 14 kg were randomly assigned to receive dolutegravir-based ART (350 participants) or standard care (357). The median age was 12.2 years (range, 2.9 to 18.0), the median weight was 30.7 kg (range, 14.0 to 85.0), and 49% of the participants were girls. By design, 311 participants (44%) started first-line ART (with 92% of those in the standard-care group receiving efavirenz-based ART), and 396 (56%) started second-line ART (with 98% of those in the standard-care group receiving boosted protease inhibitor-based ART). The median follow-up was 142 weeks. By 96 weeks, 47 participants in the dolutegravir group and 75 in the standard-care group had treatment failure (estimated probability, 0.14 vs. 0.22; difference, -0.08; 95% confidence interval, -0.14 to -0.03; P = 0.004). Treatment effects were similar with first- and second-line therapies (P = 0.16 for heterogeneity). A total of 35 participants in the dolutegravir group and 40 in the standard-care group had at least one serious adverse event (P = 0.53), and 73 and 86, respectively, had at least one adverse event of grade 3 or higher (P = 0.24). At least one ART-modifying adverse event occurred in 5 participants in the dolutegravir group and in 17 in the standard-care group (P = 0.01). CONCLUSIONS: In this trial involving children and adolescents with HIV-1 infection who were starting first- or second-line treatment, dolutegravir-based ART was superior to standard care. (Funded by ViiV Healthcare; ODYSSEY ClinicalTrials.gov number, NCT02259127; EUDRACT number, 2014-002632-14; and ISRCTN number, ISRCTN91737921.).


Asunto(s)
Antirretrovirales/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Inhibidores de Integrasa VIH/uso terapéutico , VIH-1 , Compuestos Heterocíclicos con 3 Anillos/uso terapéutico , Oxazinas/uso terapéutico , Piperazinas/uso terapéutico , Piridonas/uso terapéutico , Administración Oral , Adolescente , Alquinos/uso terapéutico , Antirretrovirales/efectos adversos , Benzoxazinas/uso terapéutico , Niño , Preescolar , Colesterol/sangre , Ciclopropanos/uso terapéutico , Quimioterapia Combinada , Femenino , Infecciones por VIH/virología , Inhibidores de Integrasa VIH/administración & dosificación , Inhibidores de Integrasa VIH/efectos adversos , Inhibidores de la Proteasa del VIH/uso terapéutico , VIH-1/aislamiento & purificación , Compuestos Heterocíclicos con 3 Anillos/administración & dosificación , Compuestos Heterocíclicos con 3 Anillos/efectos adversos , Humanos , Masculino , Oxazinas/administración & dosificación , Oxazinas/efectos adversos , Piperazinas/administración & dosificación , Piperazinas/efectos adversos , Piridonas/administración & dosificación , Piridonas/efectos adversos , Carga Viral/efectos de los fármacos
2.
J Clin Immunol ; 43(8): 2076-2089, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37740092

RESUMEN

Variants of uncertain significance (VUS) in CTLA4 are frequently identified in patients with antibody deficiency or immune dysregulation syndromes including, but not limited to, patients with multi-organ autoimmunity and autoinflammation. However, to ascertain the diagnosis of CTLA4 insufficiency, the functional relevance of each variant needs to be determined. Currently, various assays have been proposed to assess the functionality of CTLA4 VUS, including the analysis of transendocytosis, the biological function of CTLA4 to capture CD80 molecules from antigen presenting cells. Challenges of this assay include weak fluorescence intensity of the internalized ligand, poor reproducibility, and poor performance upon analyzing thawed cells. In addition, the distinction of pathogenic from non-pathogenic variants and from wild-type CTLA4, and the classification of the different VUS according to its level of CTLA4 dysfunction, would be desirable. We developed a novel CD80-expressing cell line for the evaluation of CD80-transendocytosis and compared it to the published transendocytosis assay. Our approach showed lower inter-assay variability and better robustness regardless the type of starting material (fresh or thawed peripheral mononuclear cells). In addition, receiver operating characteristic analysis showed 100% specificity, avoiding false positive results and allowing for a clear distinction between pathogenic and non-pathogenic variants in CTLA4-variant carriers. With our transendocytosis assay, we assessed the pathogenicity of 24 distinct CTLA4 variants from patients submitted to our diagnostic unit. Significantly impaired transendocytosis was demonstrated for 17 CTLA4 variants, whereas seven variants tested normal. In conclusion, our upgraded transendocytosis assay allows a reliable assessment of newly identified variants in CTLA4.


Asunto(s)
Células Presentadoras de Antígenos , Autoinmunidad , Humanos , Antígeno CTLA-4/genética , Citometría de Flujo , Reproducibilidad de los Resultados
3.
J Clin Immunol ; 43(1): 46-56, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36121535

RESUMEN

Almost 2 years into the pandemic and with vaccination of children significantly lagging behind adults, long-term pediatric humoral immune responses to SARS-CoV-2 are understudied. The C19.CHILD Hamburg (COVID-19 Child Health Investigation of Latent Disease) Study is a prospective cohort study designed to identify and follow up children and their household contacts infected in the early 2020 first wave of SARS-CoV-2. We screened 6113 children < 18 years by nasopharyngeal swab-PCR in a low-incidence setting after general lockdown, from May 11 to June 30, 2020. A total of 4657 participants underwent antibody testing. Positive tests were followed up by repeated PCR and serological testing of all household contacts over 6 months. In total, the study identified 67 seropositive children (1.44%); the median time after infection at first presentation was 83 days post-symptom onset (PSO). Follow-up of household contacts showed less than 100% seroprevalence in most families, with higher seroprevalence in families with adult index cases compared to pediatric index cases (OR 1.79, P = 0.047). Most importantly, children showed sustained seroconversion up to 9 months PSO, and serum antibody concentrations persistently surpassed adult levels (ratio serum IgG spike children vs. adults 90 days PSO 1.75, P < 0.001; 180 days 1.38, P = 0.01; 270 days 1.54, P = 0.001). In a low-incidence setting, SARS-CoV-2 infection and humoral immune response present distinct patterns in children including higher antibody levels, and lower seroprevalence in families with pediatric index cases. Children show long-term SARS-CoV-2 antibody responses. These findings are relevant to novel variants with increased disease burden in children, as well as for the planning of age-appropriate vaccination strategies.


Asunto(s)
Formación de Anticuerpos , COVID-19 , Adulto , Humanos , Niño , SARS-CoV-2 , COVID-19/diagnóstico , COVID-19/epidemiología , Estudios Prospectivos , Estudios Seroepidemiológicos , Control de Enfermedades Transmisibles , Anticuerpos Antivirales
4.
J Clin Immunol ; 42(3): 500-511, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34973143

RESUMEN

PURPOSE: The purpose of this phase 3 study was to evaluate the efficacy, pharmacokinetics (PK), and safety of Immune Globulin Subcutaneous (Human), 20% Caprylate/Chromatography Purified (IGSC 20%) in patients with primary immunodeficiency (PI). METHODS: Immunoglobulin treatment-experienced subjects with PI received 52 weeks of IGSC 20% given weekly at the same dose as the subject's previous IgG regimen (DAF 1:1); the minimum dose was 100 mg/kg/week. The primary endpoint was serious bacterial infections (SBIs [null vs alternative hypothesis: SBI rate per person per year ≥ 1 vs < 1]). IgG subclasses and specific pathogen antibody levels were also measured. RESULTS: Sixty-one subjects (19 children [≤ 12 years], 10 adolescents [> 12-16 years], and 32 adults) were enrolled. The rate of SBIs per person per year was 0.017. The 1-sided 99% upper confidence limit was 0.036 (< 1), and the null hypothesis was rejected. The rate of hospitalization due to infection per person per year was 0.017 (2-sided 95% confidence interval: 0.008-0.033) overall. The mean trough total IgG concentrations were comparable to the previous IgG replacement regimen. The average of the individual mean trough ratios (IGSC 20%:previous regimen) was 1.078 (range: 0.83-1.54). The average steady-state mean trough IgG concentrations were 947.64 and 891.37 mg/dL, respectively. Seven subjects had serious treatment-emergent adverse events (TEAEs); none was drug-related. The rate of all TEAEs, including local infusion site reactions, during 3045 IGSC 20% infusions was 0.135. Most TEAEs were mild or moderate. CONCLUSIONS: IGSC 20% demonstrated efficacy and good safety and tolerability in subjects with PI.


Asunto(s)
Síndromes de Inmunodeficiencia , Adolescente , Adulto , Niño , Humanos , Inmunoglobulina G/uso terapéutico , Inmunoglobulinas Intravenosas , Síndromes de Inmunodeficiencia/diagnóstico , Síndromes de Inmunodeficiencia/tratamiento farmacológico , Factores Inmunológicos/uso terapéutico , Infusiones Subcutáneas
5.
J Med Virol ; 94(10): 5038-5043, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35662058

RESUMEN

We aimed to provide in vitro data on the neutralization capacity of different monoclonal antibody (mAb) preparations against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) delta and omicron variant, respectively, and describe the in vivo RNA kinetics of coronavirus disease 2019 (COVID-19) patients treated with the respective mAbs. Virus neutralization assays were performed to assess the neutralizing effect of the mAb formulations casirivimab/imdevimab and sotrovimab on the SARS-CoV-2 delta and omicron variant. Additionally, respiratory tract SARS-CoV-2 RNA kinetics are provided for 25 COVID-19 patients infected with either delta variant (n = 18) or omicron variant (n = 7) treated with the respective mAb formulations during their hospital stay. In the virus neutralization assay, sotrovimab exhibits neutralizing capacity at therapeutically achievable concentrations against the SARS-CoV-2 delta and omicron variant. In contrast, casivirimab/imdevimab had neutralizing capacity against the delta variant but failed neutralization against the omicron variant except for a very high concentration above the currently recommended therapeutic dosage. In patients with delta variant infections treated with casivirimab/imdevimab, we observed a rapid decrease of respiratory viral RNA at day 3 after mAb therapy. In contrast, no such prompt decline was observed in patients with delta variant or omicron variant infections receiving sotrovimab.


Asunto(s)
Antineoplásicos Inmunológicos , Tratamiento Farmacológico de COVID-19 , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales Humanizados , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Humanos , Glicoproteínas de Membrana/genética , Pruebas de Neutralización , ARN Viral , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus , Resultado del Tratamiento , Proteínas del Envoltorio Viral/genética
6.
Int J Legal Med ; 136(1): 189-192, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34510268

RESUMEN

This case report highlights details of a case of critical acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) with B1.1.7 variant in a 4-year-old girl who died due to pneumonia and pulmonary hemorrhage. The girl was referred to our University ECMO Center from another University hospital for veno-arterial extracorporeal membrane oxygenation (VA-ECMO). In the clinical course, superinfection with Pseudomonas aeruginosa was detected. Virological evidence of herpes simplex sepsis was also obtained in blood samples on her day of death. Transcription polymerase chain reaction (PCR) confirmed SARS-CoV-2 infection in lung tissue. Postmortem computed tomography showed pulmonary hemorrhage with inhomogeneous density values in both lungs. Lung tissue showed no ventilated areas. Autopsy revealed a massively congested lung with evidence of acute respiratory distress syndrome (ARDS) and pneumonia with multiple abscesses. Histopathology showed a mixture of diffuse alveolar injury with hyaline membranes, massive hemorrhage, and bronchopneumonia with multiple granulocytic abscesses. Cardiac examination revealed pericarditis. Suspicion of myocarditis or myocardial infarction could not be confirmed microscopically. To our knowledge, this is the first autopsy-based case report of the death of a previously healthy child due to the new variant B 1.1.7 in Germany.


Asunto(s)
COVID-19 , Síndrome de Dificultad Respiratoria/virología , Absceso/patología , Absceso/virología , COVID-19/diagnóstico , Preescolar , Resultado Fatal , Femenino , Alemania , Humanos , Pulmón/diagnóstico por imagen , Pulmón/patología , SARS-CoV-2
7.
Neuropediatrics ; 53(5): 381-384, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35843218

RESUMEN

The 12 years old male patient presented here suffers from neuronal ceroid lipofuscinoses 2 (CLN2) (MIM# 204500) and receives intracerebroventricular enzyme replacement therapy (ICV-ERT) every 14 days. After the emergence of the coronavirus disease 2019 (COVID-19) pandemic, routine care of children and adolescents with rare chronic diseases has become challenging. Although, in general, children do not develop severe COVID-19, when severe acute respiratory syndrome coronavirus 2 infection was detected by polymerase chain reaction-screening examination in our CLN2 patient before hospital admission for ICV-ERT, he was regarded to be at risk. Upon diagnosis, the patient developed respiratory deterioration symptoms and was admitted to our pediatric intensive care unit to receive oxygen, remdesivir, and steroids. As far as we know, this is the first CLN2 patient receiving intraventricular enzyme therapy with COVID-19 who required intensive care treatment and specific therapy.


Asunto(s)
COVID-19 , Lipofuscinosis Ceroideas Neuronales , Adolescente , COVID-19/complicaciones , Niño , Dipeptidil-Peptidasas y Tripeptidil-Peptidasas/uso terapéutico , Terapia de Reemplazo Enzimático , Humanos , Masculino , Lipofuscinosis Ceroideas Neuronales/complicaciones , Lipofuscinosis Ceroideas Neuronales/tratamiento farmacológico , Oxígeno , Tripeptidil Peptidasa 1
8.
J Clin Immunol ; 41(8): 1804-1838, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34390440

RESUMEN

Hyper-IgE syndromes and chronic mucocutaneous candidiasis constitute rare primary immunodeficiency syndromes with an overlapping clinical phenotype. In recent years, a growing number of underlying genetic defects have been identified. To characterize the underlying genetic defects in a large international cohort of 275 patients, of whom 211 had been clinically diagnosed with hyper-IgE syndrome and 64 with chronic mucocutaneous candidiasis, targeted panel sequencing was performed, relying on Agilent HaloPlex and Illumina MiSeq technologies. The targeted panel sequencing approach allowed us to identify 87 (32 novel and 55 previously described) mutations in 78 patients, which generated a diagnostic success rate of 28.4%. Specifically, mutations in DOCK8 (26 patients), STAT3 (21), STAT1 (15), CARD9 (6), AIRE (3), IL17RA (2), SPINK5 (3), ZNF341 (2), CARMIL2/RLTPR (1), IL12RB1 (1), and WAS (1) have been detected. The most common clinical findings in this cohort were elevated IgE (81.5%), eczema (71.7%), and eosinophilia (62.9%). Regarding infections, 54.7% of patients had a history of radiologically proven pneumonia, and 28.3% have had other serious infections. History of fungal infection was noted in 53% of cases and skin abscesses in 52.9%. Skeletal or dental abnormalities were observed in 46.2% of patients with a characteristic face being the most commonly reported feature (23.1%), followed by retained primary teeth in 18.9% of patients. Targeted panel sequencing provides a cost-effective first-line genetic screening method which allows for the identification of mutations also in patients with atypical clinical presentations and should be routinely implemented in referral centers.


Asunto(s)
Candidiasis Mucocutánea Crónica/genética , Síndrome de Job/genética , Adolescente , Adulto , Candidiasis Mucocutánea Crónica/sangre , Niño , Preescolar , Estudios de Cohortes , Eccema/genética , Eosinofilia/genética , Femenino , Humanos , Inmunoglobulina E/sangre , Lactante , Síndrome de Job/sangre , Masculino , Persona de Mediana Edad , Mutación , Adulto Joven
9.
J Allergy Clin Immunol ; 146(4): 901-911, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32278790

RESUMEN

BACKGROUND: An increasing number of NFKB1 variants are being identified in patients with heterogeneous immunologic phenotypes. OBJECTIVE: To characterize the clinical and cellular phenotype as well as the management of patients with heterozygous NFKB1 mutations. METHODS: In a worldwide collaborative effort, we evaluated 231 individuals harboring 105 distinct heterozygous NFKB1 variants. To provide evidence for pathogenicity, each variant was assessed in silico; in addition, 32 variants were assessed by functional in vitro testing of nuclear factor of kappa light polypeptide gene enhancer in B cells (NF-κB) signaling. RESULTS: We classified 56 of the 105 distinct NFKB1 variants in 157 individuals from 68 unrelated families as pathogenic. Incomplete clinical penetrance (70%) and age-dependent severity of NFKB1-related phenotypes were observed. The phenotype included hypogammaglobulinemia (88.9%), reduced switched memory B cells (60.3%), and respiratory (83%) and gastrointestinal (28.6%) infections, thus characterizing the disorder as primary immunodeficiency. However, the high frequency of autoimmunity (57.4%), lymphoproliferation (52.4%), noninfectious enteropathy (23.1%), opportunistic infections (15.7%), autoinflammation (29.6%), and malignancy (16.8%) identified NF-κB1-related disease as an inborn error of immunity with immune dysregulation, rather than a mere primary immunodeficiency. Current treatment includes immunoglobulin replacement and immunosuppressive agents. CONCLUSIONS: We present a comprehensive clinical overview of the NF-κB1-related phenotype, which includes immunodeficiency, autoimmunity, autoinflammation, and cancer. Because of its multisystem involvement, clinicians from each and every medical discipline need to be made aware of this autosomal-dominant disease. Hematopoietic stem cell transplantation and NF-κB1 pathway-targeted therapeutic strategies should be considered in the future.


Asunto(s)
Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Heterocigoto , Mutación , Subunidad p50 de NF-kappa B/genética , Fenotipo , Adulto , Anciano , Autoinmunidad/genética , Variación Biológica Poblacional , Biomarcadores , Manejo de la Enfermedad , Femenino , Técnica del Anticuerpo Fluorescente , Estudios de Asociación Genética/métodos , Humanos , Inmunohistoquímica , Estimación de Kaplan-Meier , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Pronóstico , Tomografía Computarizada por Rayos X
10.
Infection ; 47(5): 847-852, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31190299

RESUMEN

PURPOSE: Due to early antenatal screening and treatment, HIV mother-to-child transmission (MTCT) rarely occurs in Germany. The study aimed to investigate the impact on prevalence of HIV infection in the antenatal population and the incidence of late-presenting HIV-infected mothers attributable to increased numbers of refugees. METHODS: Retrospective analysis and comparison were performed for all deliveries in HIV-infected pregnant women presenting to medical care in Munich (southern Germany) and Hamburg (northern Germany) covering two time periods, A (2010-2012) and B (2013-2015). RESULTS: In Munich, deliveries in HIV-infected pregnant women increased 1.6-fold from period A (n = 50) to B (n = 79) with late-presenting cases rising significantly from 2% (1/50) in period A to 13% (10/79) in B. In contrast, late-presenting cases in Hamburg decreased from 14% (14/100) in period A to 7% (7/107) in B, while the total number of HIV-infected women giving birth remained stable. From 2010 to 2015, one late-presenting pregnant woman transmitted HIV in Munich by presumed in utero mode of infection (case reviewed here), while no MTCT occurred in Hamburg. CONCLUSIONS: HIV infections diagnosed late in pregnancy and leading to delayed ART initiation are rising in Munich compared to Hamburg. Antenatal care of HIV-infected pregnant women in Munich appears to have been more affected by the recent refugee influx than Hamburg. Our study highlights the importance of screening all pregnant women for HIV early in pregnancy and providing timely health care access for pregnant refugees and asylum seekers to effectively prevent MTCT in Germany.


Asunto(s)
Infecciones por VIH/epidemiología , Transmisión Vertical de Enfermedad Infecciosa/estadística & datos numéricos , Complicaciones Infecciosas del Embarazo/epidemiología , Complicaciones Infecciosas del Embarazo/virología , Refugiados , Adulto , Fármacos Anti-VIH/uso terapéutico , Femenino , Geografía , Alemania/epidemiología , Infecciones por VIH/diagnóstico , Infecciones por VIH/tratamiento farmacológico , VIH-1 , Accesibilidad a los Servicios de Salud , Humanos , Embarazo , Prevalencia , Estudios Retrospectivos , Tiempo de Tratamiento , Adulto Joven
11.
Brain ; 141(8): 2299-2311, 2018 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-29985992

RESUMEN

The transcription factor BCL11B is essential for development of the nervous and the immune system, and Bcl11b deficiency results in structural brain defects, reduced learning capacity, and impaired immune cell development in mice. However, the precise role of BCL11B in humans is largely unexplored, except for a single patient with a BCL11B missense mutation, affected by multisystem anomalies and profound immune deficiency. Using massively parallel sequencing we identified 13 patients bearing heterozygous germline alterations in BCL11B. Notably, all of them are affected by global developmental delay with speech impairment and intellectual disability; however, none displayed overt clinical signs of immune deficiency. Six frameshift mutations, two nonsense mutations, one missense mutation, and two chromosomal rearrangements resulting in diminished BCL11B expression, arose de novo. A further frameshift mutation was transmitted from a similarly affected mother. Interestingly, the most severely affected patient harbours a missense mutation within a zinc-finger domain of BCL11B, probably affecting the DNA-binding structural interface, similar to the recently published patient. Furthermore, the most C-terminally located premature termination codon mutation fails to rescue the progenitor cell proliferation defect in hippocampal slice cultures from Bcl11b-deficient mice. Concerning the role of BCL11B in the immune system, extensive immune phenotyping of our patients revealed alterations in the T cell compartment and lack of peripheral type 2 innate lymphoid cells (ILC2s), consistent with the findings described in Bcl11b-deficient mice. Unsupervised analysis of 102 T lymphocyte subpopulations showed that the patients clearly cluster apart from healthy children, further supporting the common aetiology of the disorder. Taken together, we show here that mutations leading either to BCL11B haploinsufficiency or to a truncated BCL11B protein clinically cause a non-syndromic neurodevelopmental delay. In addition, we suggest that missense mutations affecting specific sites within zinc-finger domains might result in distinct and more severe clinical outcomes.


Asunto(s)
Trastornos del Neurodesarrollo/genética , Proteínas Represoras/genética , Proteínas Represoras/fisiología , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/fisiología , Adolescente , Animales , Niño , Preescolar , Femenino , Regulación de la Expresión Génica/genética , Mutación de Línea Germinal , Haploinsuficiencia , Heterocigoto , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Lactante , Linfocitos/patología , Linfocitos/fisiología , Masculino , Ratones , Mutación , Proteínas Represoras/metabolismo , Linfocitos T/fisiología , Factores de Transcripción/genética , Proteínas Supresoras de Tumor/metabolismo
12.
J Allergy Clin Immunol ; 141(4): 1427-1438, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-28782633

RESUMEN

BACKGROUND: Primary antibody deficiencies (PADs) are the most frequent primary immunodeficiencies in human subjects. The genetic causes of PADs are largely unknown. Sec61 translocon alpha 1 subunit (SEC61A1) is the major subunit of the Sec61 complex, which is the main polypeptide-conducting channel in the endoplasmic reticulum membrane. SEC61A1 is a target gene of spliced X-box binding protein 1 and strongly induced during plasma cell (PC) differentiation. OBJECTIVE: We identified a novel genetic defect and studied its pathologic mechanism in 11 patients from 2 unrelated families with PADs. METHODS: Whole-exome and targeted sequencing were conducted to identify novel genetic mutations. Functional studies were carried out ex vivo in primary cells of patients and in vitro in different cell lines to assess the effect of SEC61A1 mutations on B-cell differentiation and survival. RESULTS: We investigated 2 families with patients with hypogammaglobulinemia, severe recurrent respiratory tract infections, and normal peripheral B- and T-cell subpopulations. On in vitro stimulation, B cells showed an intrinsic deficiency to develop into PCs. Genetic analysis and targeted sequencing identified novel heterozygous missense (c.254T>A, p.V85D) and nonsense (c.1325G>T, p.E381*) mutations in SEC61A1, segregating with the disease phenotype. SEC61A1-V85D was deficient in cotranslational protein translocation, and it disturbed the cellular calcium homeostasis in HeLa cells. Moreover, SEC61A1-V85D triggered the terminal unfolded protein response in multiple myeloma cell lines. CONCLUSION: We describe a monogenic defect leading to a specific PC deficiency in human subjects, expanding our knowledge about the pathogenesis of antibody deficiencies.


Asunto(s)
Síndromes de Inmunodeficiencia/genética , Mutación/genética , Células Plasmáticas/patología , Canales de Translocación SEC/genética , Agammaglobulinemia/genética , Agammaglobulinemia/metabolismo , Agammaglobulinemia/patología , Linfocitos B/metabolismo , Linfocitos B/patología , Calcio/metabolismo , Diferenciación Celular/genética , Línea Celular , Línea Celular Tumoral , Exoma/genética , Células HEK293 , Células HeLa , Heterocigoto , Humanos , Síndromes de Inmunodeficiencia/metabolismo , Células Plasmáticas/metabolismo , Transporte de Proteínas/genética , Infecciones del Sistema Respiratorio/genética , Infecciones del Sistema Respiratorio/metabolismo , Infecciones del Sistema Respiratorio/patología , Linfocitos T/metabolismo , Linfocitos T/patología , Respuesta de Proteína Desplegada/genética
14.
Blood ; 128(2): 227-38, 2016 07 14.
Artículo en Inglés | MEDLINE | ID: mdl-27099149

RESUMEN

Autoimmune lymphoproliferative syndrome (ALPS) is a human disorder characterized by defective Fas signaling, resulting in chronic benign lymphoproliferation and accumulation of TCRαß(+) CD4(-) CD8(-) double-negative T (DNT) cells. Although their phenotype resembles that of terminally differentiated or exhausted T cells, lack of KLRG1, high eomesodermin, and marginal T-bet expression point instead to a long-lived memory state with potent proliferative capacity. Here we show that despite their terminally differentiated phenotype, human ALPS DNT cells exhibit substantial mitotic activity in vivo. Notably, hyperproliferation of ALPS DNT cells is associated with increased basal and activation-induced phosphorylation of serine-threonine kinases Akt and mechanistic target of rapamycin (mTOR). The mTOR inhibitor rapamycin abrogated survival and proliferation of ALPS DNT cells, but not of CD4(+) or CD8(+) T cells in vitro. In vivo, mTOR inhibition reduced proliferation and abnormal differentiation by DNT cells. Importantly, increased mitotic activity and hyperactive mTOR signaling was also observed in recently defined CD4(+) or CD8(+) precursor DNT cells, and mTOR inhibition specifically reduced these cells in vivo, indicating abnormal programming of Fas-deficient T cells before the DNT stage. Thus, our results identify the mTOR pathway as a major regulator of lymphoproliferation and aberrant differentiation in ALPS.


Asunto(s)
Síndrome Linfoproliferativo Autoinmune/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Diferenciación Celular/inmunología , Transducción de Señal/inmunología , Serina-Treonina Quinasas TOR/inmunología , Adolescente , Adulto , Síndrome Linfoproliferativo Autoinmune/patología , Linfocitos T CD4-Positivos/patología , Linfocitos T CD8-positivos/patología , Niño , Preescolar , Femenino , Humanos , Lectinas Tipo C/inmunología , Antígenos Comunes de Leucocito/inmunología , Masculino , Proteínas Proto-Oncogénicas c-akt/inmunología , Receptores de Antígenos de Linfocitos T/inmunología , Receptores Inmunológicos , Transactivadores/inmunología
15.
Euro Surveill ; 23(12)2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29589578

RESUMEN

BackgroundIn Germany, the incidence of tuberculosis (TB) in children has been on the rise since 2009. High numbers of foreign-born asylum seekers have contributed considerably to the disease burden. Therefore, effective screening strategies for latent TB infection (LTBI) and active TB in asylum seeking children are needed. Aim: Our aim was to investigate the prevalence of LTBI and active TB in asylum seeking children up to 15 years of age in two geographic regions in Germany. Methods: Screening for TB was performed in children in asylum seeker reception centres by tuberculin skin test (TST) or interferon gamma release assay (IGRA). Children with positive results were evaluated for active TB. Additionally, country of origin, sex, travel time, TB symptoms, TB contact and Bacille Calmette-Guérin (BCG) vaccination status were registered. Results: Of 968 screened children 66 (6.8%) had TB infection (58 LTBI, 8 active TB). LTBI prevalence was similar in children from high (Afghanistan) and low (Syria) incidence countries (8.7% vs 6.4%). There were no differences regarding sex, age or travel time between infected and non-infected children. Children under the age of 6 years were at higher risk of progression to active TB (19% vs 2% respectively, p=0,07). Most children (7/8) with active TB were asymptomatic at the time of diagnosis. None of the children had been knowingly exposed to TB. Conclusions: Asylum seeking children from high and low incidence countries are both at risk of developing LTBI or active TB. Universal TB screening for all asylum seeking children should be considered.


Asunto(s)
Ensayos de Liberación de Interferón gamma/métodos , Tuberculosis Latente/diagnóstico , Tuberculosis Latente/epidemiología , Refugiados/estadística & datos numéricos , Prueba de Tuberculina/métodos , Tuberculosis/diagnóstico , Tuberculosis/epidemiología , Afganistán/etnología , Niño , Preescolar , Atención a la Salud , Femenino , Alemania/epidemiología , Humanos , Incidencia , Lactante , Tuberculosis Latente/etnología , Masculino , Prevalencia , Siria/etnología , Viaje , Tuberculosis/etnología
17.
BMC Nephrol ; 18(1): 96, 2017 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-28320387

RESUMEN

BACKGROUND: Influenza A infections have been described to cause secondary hemolytic uremic syndrome and to trigger atypical hemolytic uremic syndrome (aHUS) in individuals with an underlying genetic complement dysregulation. To date, influenza B has not been reported to trigger aHUS. CASE PRESENTATION: A 6-month-old boy presented with hemolytic uremic syndrome triggered by influenza B infection. Initially the child recovered spontaneously. When he relapsed Eculizumab treatment was initiated, resulting in complete and sustained remission. A pathogenic mutation in membrane cofactor protein (MCP) was detected. CONCLUSION: Influenza B is a trigger for aHUS and might be underreported as such. Influenza vaccination may protect patients at risk.


Asunto(s)
Síndrome Hemolítico Urémico Atípico/diagnóstico , Síndrome Hemolítico Urémico Atípico/etiología , Virus de la Influenza B/aislamiento & purificación , Gripe Humana/complicaciones , Gripe Humana/diagnóstico , Síndrome Hemolítico Urémico Atípico/terapia , Diagnóstico Diferencial , Humanos , Lactante , Virus de la Influenza B/clasificación , Gripe Humana/terapia , Masculino , Resultado del Tratamiento
18.
J Clin Immunol ; 36(1): 73-84, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26604104

RESUMEN

PURPOSE: Gain-of-function (GOF) mutations in the signal transducer and activator of transcription 1 (STAT1) result in unbalanced STAT signaling and cause immune dysregulation and immunodeficiency. The latter is often characterized by the susceptibility to recurrent Candida infections, resulting in the clinical picture of chronic mucocutaneous candidiasis (CMC). This study aims to assess the frequency of GOF STAT1 mutations in a large international cohort of CMC patients. METHODS: STAT1 was sequenced in genomic DNA from 57 CMC patients and 35 healthy family members. The functional relevance of nine different STAT1 variants was shown by flow cytometric analysis of STAT1 phosphorylation in patients' peripheral blood cells (PBMC) after stimulation with interferon (IFN)-α, IFN-γ or interleukin-27 respectively. Extended clinical data sets were collected and summarized for 26 patients. RESULTS: Heterozygous mutations within STAT1 were identified in 35 of 57 CMC patients (61%). Out of 39 familial cases from 11 families, 26 patients (67%) from 9 families and out of 18 sporadic cases, 9 patients (50%) were shown to have heterozygous mutations within STAT1. Thirteen distinct STAT1 mutations are reported in this paper. Eight of these mutations are known to cause CMC (p.M202V, p.A267V, p.R274W, p.R274Q, p.T385M, p.K388E, p.N397D, and p.F404Y). However, five STAT1 variants (p.F172L, p.Y287D, p.P293S, p.T385K and p.S466R) have not been reported before in CMC patients. CONCLUSION: STAT1 mutations are frequently observed in patients suffering from CMC. Thus, sequence analysis of STAT1 in CMC patients is advised. Measurement of IFN- or IL-induced STAT1 phosphorylation in PBMC provides a fast and reliable diagnostic tool and should be carried out in addition to genetic testing.


Asunto(s)
Candidiasis Mucocutánea Crónica/diagnóstico , Síndromes de Inmunodeficiencia/diagnóstico , Leucocitos Mononucleares/inmunología , Mutación/genética , Factor de Transcripción STAT1/metabolismo , Adulto , Candidiasis Mucocutánea Crónica/genética , Células Cultivadas , Citocinas/metabolismo , Análisis Mutacional de ADN , Femenino , Humanos , Síndromes de Inmunodeficiencia/genética , Masculino , Linaje , Fenotipo , Estructura Terciaria de Proteína/genética , Factor de Transcripción STAT1/genética
19.
N Engl J Med ; 365(8): 718-24, 2011 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-21793736

RESUMEN

An outbreak caused by Shiga-toxin­producing Escherichia coli O104:H4 occurred in Germany in May and June of 2011, with more than 3000 persons infected. Here, we report a cluster of cases associated with a single family and describe an open-source genomic analysis of an isolate from one member of the family. This analysis involved the use of rapid, bench-top DNA sequencing technology, open-source data release, and prompt crowd-sourced analyses. In less than a week, these studies revealed that the outbreak strain belonged to an enteroaggregative E. coli lineage that had acquired genes for Shiga toxin 2 and for antibiotic resistance.


Asunto(s)
Infecciones por Escherichia coli/microbiología , Genoma Bacteriano , Síndrome Hemolítico-Urémico/microbiología , Escherichia coli Shiga-Toxigénica/genética , Adolescente , Técnicas de Tipificación Bacteriana , Niño , Diarrea/epidemiología , Diarrea/microbiología , Heces/microbiología , Femenino , Alemania , Síndrome Hemolítico-Urémico/epidemiología , Humanos , Masculino , Datos de Secuencia Molecular , Filogenia , Plásmidos/genética , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN , Escherichia coli Shiga-Toxigénica/clasificación , Escherichia coli Shiga-Toxigénica/aislamiento & purificación
20.
Int J Health Geogr ; 13: 35, 2014 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-25270342

RESUMEN

BACKGROUND: Malaria is a mosquito-borne parasitic disease that causes severe mortality and morbidity, particularly in Sub-Saharan Africa. As the vectors predominantly bite between dusk and dawn, risk of infection is determined by the abundance of P. falciparum infected mosquitoes in the surroundings of the households. Remote sensing is commonly employed to detect associations between land use/land cover (LULC) and mosquito-borne diseases. Due to challenges in LULC identification and the fact that LULC merely functions as a proxy for mosquito abundance, assuming spatially homogenous relationships may lead to overgeneralized conclusions. METHODS: Data on incidence of P. falciparum parasitaemia were recorded by active and passive follow-up over two years. Nine LULC types were identified through remote sensing and ground-truthing. Spatial associations of LULC and P. falciparum parasitaemia rate were described in a semi-parametric geographically weighted Poisson regression model. RESULTS: Complete data were available for 878 individuals, with an annual P. falciparum rate of 3.2 infections per person-year at risk. The influences of built-up areas (median incidence rate ratio (IRR): 0.94, IQR: 0.46), forest (median IRR: 0.9, IQR: 0.51), swampy areas (median IRR: 1.15, IQR: 0.88), as well as banana (median IRR: 1.02, IQR: 0.25), cacao (median IRR: 1.33, IQR: 0.97) and orange plantations (median IRR: 1.11, IQR: 0.68) on P. falciparum rate show strong spatial variations within the study area. Incorporating spatial variability of LULC variables increased model performance compared to the spatially homogenous model. CONCLUSIONS: The observed spatial variability of LULC influence in parasitaemia would have been masked by traditional Poisson regression analysis assuming a spatially constant influence of all variables. We conclude that the spatially varying effects of LULC on P. falciparum parasitaemia may in fact be associated with co-factors not captured by remote sensing, and suggest that future studies assess small-scale spatial variation of vegetation to circumvent generalised assumptions on ecological associations that may in fact be artificial.


Asunto(s)
Mapeo Geográfico , Malaria Falciparum/etnología , Malaria Falciparum/transmisión , Plasmodium falciparum/aislamiento & purificación , Población Rural , Estudios de Seguimiento , Ghana/etnología , Humanos , Lactante
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