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1.
Front Immunol ; 15: 1432226, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39139562

RESUMO

Introduction: The early transcription unit 3 (E3) of human adenoviruses (HAdVs) encodes several immunoevasins, including the E3/49K protein, which is unique for species D of HAdVs. It is expressed as surface transmembrane protein and shed. E3/49K of HAdV-D64 binds to the protein tyrosine phosphatase surface receptor CD45, thereby modulating activation of T and NK cells. Methods: Considering that E3/49K represents the most polymorphic viral protein among species D HAdVs, we demonstrate here that all tested E3/49K orthologs bind to the immunologically important regulator CD45. Thus, this feature is conserved regardless of the pathological associations of the respective HAdV types. Results: It appeared that modulation of CD45 is a unique property restricted to HAdVs of species D. Moreover, E3/49K treatment inhibited B cell receptor (BCR) signaling and impaired BCR signal phenotypes. The latter were highly comparable to B cells having defects in the expression of CD45, suggesting E3/49K as a potential tool to investigate CD45 specific functions. Conclusion: We identified B cells as new direct target of E3/49K-mediated immune modulation, representing a novel viral immunosubversive mechanism.


Assuntos
Proteínas E3 de Adenovirus , Adenovírus Humanos , Linfócitos B , Antígenos Comuns de Leucócito , Receptores de Antígenos de Linfócitos B , Transdução de Sinais , Humanos , Receptores de Antígenos de Linfócitos B/metabolismo , Receptores de Antígenos de Linfócitos B/imunologia , Transdução de Sinais/imunologia , Antígenos Comuns de Leucócito/metabolismo , Antígenos Comuns de Leucócito/imunologia , Adenovírus Humanos/imunologia , Proteínas E3 de Adenovirus/imunologia , Proteínas E3 de Adenovirus/metabolismo , Proteínas E3 de Adenovirus/genética , Linfócitos B/imunologia , Linfócitos B/metabolismo , Infecções por Adenovirus Humanos/imunologia , Infecções por Adenovirus Humanos/virologia , Infecções por Adenovirus Humanos/metabolismo , Células HEK293
2.
Transplant Cell Ther ; 29(6): 391.e1-391.e7, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36934995

RESUMO

Human adenovirus (HAdV) infection is a serious complication that can lead to significant morbidity and mortality, especially in immunocompromised pediatric patients undergoing allogeneic hematopoietic stem cell transplantation (HSCT). Control and elimination of HAdV requires the presence of the respective antiviral T cells, and adoptive transfer of virus-specific T cells has become an important new treatment option for patients refractory to antiviral treatment. Although the adenoviral capsid protein hexon is known to be a major immunodominant T cell target across HAdV species, up to 30% of HAdV-seropositive donors show no T cell responses to the overlapping peptide pool spanning the entire protein. Our group recently verified the capsid protein penton as a second immunodominant target in HAdV infection. Here we aimed to investigate the prevalence of both penton-specific and hexon-specific HAdV T cells and their impact in virus control after HSCT. We analyzed the prevalence and characteristics of HAdV-specific T cells in 33 consecutive pediatric patients with HAdV reactivation following allogeneic HSCT and correlated them with viral load analysis. Our study demonstrates that penton is an important immunodominant target antigen of HAdV reactivation/ infection after HSCT in most patients. We demonstrate that in the majority of patients, both penton- and hexon-specific T cells appear at similar time intervals after transplantation. Despite the prevalence for either hexon-specific or penton-specific T cells in individual patients, we were unable to attribute the predominance to specific HLA types or HAdV serotypes. The occurrence of HAdV-specific T cells was closely linked to viral control, arguing for immune monitoring strategies to tailor antiviral treatment and adoptive T cell therapy.


Assuntos
Infecções por Adenovirus Humanos , Adenovírus Humanos , Transplante de Células-Tronco Hematopoéticas , Humanos , Criança , Proteínas do Capsídeo , Linfócitos T , Adenoviridae , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Infecções por Adenovirus Humanos/epidemiologia , Infecções por Adenovirus Humanos/etiologia , Antivirais
3.
J Heart Lung Transplant ; 42(4): 533-538, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36526496

RESUMO

BACKGROUND: COVID-19 causes high morbidity and mortality in adult lung transplant (LTX) recipients. Data on COVID-19 in children after LTX is limited. We report the clinical presentation and outcome of SARS-CoV-2 infection in 19 pediatric LTX recipients. METHODS: Between March 2020 and June 2022, SARS-CoV-2 testing was performed on all pediatric LTX patients with COVID-19 symptoms or contact with a SARS-CoV-2 infected person. Positive patients were prospectively evaluated for symptoms, treatment and outcome. Vaccination status and immune response were recorded. RESULTS: Nineteen out of 51 pediatric LTX recipients had a SARS-CoV-2 infection. Mean age was 12.3 years (IQR 9-17), 68% were female, 84% had preexisting comorbidities. Mean time between LTX and SARS-CoV-2 infection was 4.8 years (IQR 2-6). No patients experienced severe COVID-19: 11% were asymptomatic, and 89% had mild symptoms, primarily rhinitis (74%), fever (47%), and cough (37%). One SARS-CoV-2 positive patient was hospitalized due to combined fungal and bacterial infection. Mean duration of symptoms was 10.5 days (IQR 3-16), whereas mean period of positivity by antigen test was 21 days (IQR 9-27, p = 0.013). Preventive antiviral therapy was initiated in 3 patients. After a mean follow-up of 2.5 months (IQR 1.1-2.4), no patient reported persistent complaints related to COVID-19. Lung function tests remained stable. CONCLUSIONS: Unlike adult LTX recipients, children and adolescents are at low risk for severe COVID-19, even with risk factors beyond immunosuppression. Our findings cast doubt on the necessity of excessive isolation for these patients and should reassure clinicians and caregivers of LTX patients.


Assuntos
COVID-19 , Transplante de Pulmão , SARS-CoV-2 , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , COVID-19/complicações , COVID-19/diagnóstico , COVID-19/terapia , Teste para COVID-19 , Progressão da Doença , Pulmão , Resultado do Tratamento
4.
Virus Evol ; 8(2): veac067, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36533152

RESUMO

Type 31 of human adenovirus species A (HAdV-A31) is a significant pathogen primarily associated with diarrhoea in children but also with life-threatening disseminated disease in allogeneic haematopoietic stem cell transplant (HSCT) recipients. Nosocomial outbreaks of HAdV-A31 have been frequently described. However, the evolution of HAdV-A31 has not been studied in detail. The evolution of other HAdV types is driven either by intertypic recombination, where different types exchange genome regions, or by immune escape selection of neutralisation determinants. Complete genomic HAdV-A31 sequences from sixty diagnostic specimens of the past 18 years (2003-21) were generated, including fourteen specimens of a presumed outbreak on two HSCT wards. Additionally, twenty-three complete genomes from GenBank were added to our phylogenetic analysis as well as in silico generated and previously published restriction fragment polymorphism (RFLP) data. Phylogenetic analysis of eighty-three genomes indicated that HAdV-A31 evolved slowly with six lineages co-circulating. The two major lineages were lineage 1, which included the prototype from 1962 and nine recent isolates, and lineage 2, which split into four sublineages and included most isolates from 2003 to 2021. The average nucleotide identity within lineages was high (99.8 per cent) and identity between lineages was 98.7 and 99.2 per cent. RFLP data allowed the construction of a lower-resolution phylogeny with two additional putative lineages. Surprisingly, regions of higher diversity separating lineages were found in gene regions coding for non-structural and minor capsid proteins. Intertypic recombinations were not observed, but the phylogeny of lineage 3 was compatible with an interlineage recombination event in the fibre gene. Applying the phylogenetic analysis to the presumed nosocomial outbreak excluded two suspected transmission events and separated it into two different, simultaneous outbreaks caused by different sublineages of lineage 2. However, due to the high nucleotide identity within HAdV-A31 lineages, the proof of infection chains remains debatable. This in-depth study on the molecular phylogeny of HAdV-A31 highlights the high genetic stability of co-circulating HAdV-A31 lineages over almost six decades. It also supports the epidemiological hypothesis that HAdV-A31 circulates as an etiological agent of a childhood disease infecting immunologically naive patients without strong positive selection of immune escape variants and recombinants.

5.
Virus Evol ; 8(2): veac098, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36381230

RESUMO

Type 41 of human adenovirus species F (HAdV-F41) is a frequent aetiology of gastroenteritis in children, and nosocomial as well as kindergarten outbreaks have been frequently described. In contrast to other HAdV types, HAdV-F41 was not associated with a life-threatening disseminated disease in allogeneic haematopoietic stem cell transplant (HSCT) recipients or any severe organ infections so far. Due to the limited clinical significance, the evolution of HAdV-F41 has not been studied in detail. Recently, HAdV-F41 has been associated with severe hepatitis in young children, and interest in HAdV-F41 has skyrocketed, although the aetiology of hepatitis has not been resolved. Complete genomic HAdV-F41 sequences from thirty-two diagnostic specimens of the past 11 years (2011-22) were generated, all originating from gastroenteritis patients. Additionally, thirty-three complete HAdV-F41 genomes from GenBank were added to our phylogenetic analysis. Phylogenetic analysis of sixty-five genomes indicated that HAdV-F41 evolved with three lineages co-circulating. Lineage 1 included the prototype 'Tak' from 1973 and six isolates from 2007 to 2017 with an average nucleotide identity of 99.3 per cent. Lineage 2 included 53 isolates from 2000 to 2022, had an average nucleotide identity of 99.8 per cent, and split into two sublineages. Lineage 3, probably described for the first time in 2009, had a 45-nucleotide deletion in the long fibre gene and had evolved significantly in the short fibre and E3 region. Moreover, a recent Lineage 3 isolate from 2022 had a recombinant phylogeny of the short fibre gene. Fibres interact with cellular receptors and determine cellular tropism, whereas E3 gene products interfere with the immune recognition of HAdV-infected cells. This in-depth study on the phylogeny of HAdV-F41 discovered significant evolution of recently described Lineage 3 of HAdV-F41, possibly resulting in altered cellular tropism, virulence, and pathophysiology.

6.
Viruses ; 14(7)2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35891439

RESUMO

Human adenovirus (HAdV) can often lead to fulminant hepatitis in immunocompromised patients, mostly after reactivation of HAdV. Different risk factors, e.g., transplantation and chemotherapy, increase the risk of developing a HAdV hepatitis. We retrospectively analyzed three patients who showed the characteristics of a HAdV hepatitis observed in disseminated disease. In addition to PCR, diagnosis could be proven by pathology, CT scan, and markedly elevated transaminases. All patients had a hemato-oncologic underlying disease. Two had received a stem-cell transplant, and one was under chemotherapy including rituximab. Despite therapy with cidofovir, all patients died. As the incidence of HAdV hepatitis is low, diagnosis may be easily overlooked. No treatment approaches have yet been established. HAdV hepatitis should be considered as a differential diagnosis, especially when risk factors are present. To avoid dissemination, treatment should be initiated as soon as possible.


Assuntos
Infecções por Adenoviridae , Infecções por Adenovirus Humanos , Adenovírus Humanos , Hepatite Viral Humana , Necrose Hepática Massiva , Infecções por Adenovirus Humanos/diagnóstico , Infecções por Adenovirus Humanos/tratamento farmacológico , Infecções por Adenovirus Humanos/patologia , Adenovírus Humanos/genética , Humanos , Hospedeiro Imunocomprometido , Estudos Retrospectivos
7.
Antimicrob Resist Infect Control ; 11(1): 88, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35729671

RESUMO

BACKGROUND: Respiratory syncytial virus (RSV) causes community-acquired respiratory tract infections during winter. However, outbreaks in hospitals also occur repeatedly. In particular, patients with hematologic malignancies are at an increased risk for a severe and potentially fatal course of RSV infection. Here we present the investigation of an RSV outbreak in a hematology ward for adults following the ORION statement. METHODS: An epidemiologic and molecular outbreak analysis was performed. We developed and employed a minimal oligonucleotide probe set in target capture probe sequencing that allows cost-effective RSV-A or -B capturing to reconstruct RSV genomes from clinical samples. RESULTS: Four adult patients were involved in the outbreak caused by RSV-B in March 2019. The enforcement of the pre-existing infection control measures by effective training of hospital staff contributed to a successful containment. PCR-based RSV screening on the ward enabled early detection of new cases and rapid isolation measures. The molecular analysis demonstrated that the outbreak sequences were highly related and distinct to other RSV-B strains circulating at the same time. CONCLUSIONS: A multimodal infection control concept is essential for the timely detection and control of RSV outbreaks in patients with hematological disease. Among other measures, preventive screening for respiratory viruses is recommended. Furthermore, the integration of conventional and molecular epidemiology, such as whole-genome sequencing and variant calling, significantly contributes to the understanding of transmission pathways. Based on this, appropriate conclusions can be drawn for targeted prevention measures that have prepared us for the COVID-19 pandemic beyond the RSV approach described here.


Assuntos
COVID-19 , Infecção Hospitalar , Infecções por Vírus Respiratório Sincicial , Vírus Sincicial Respiratório Humano , Adulto , Infecção Hospitalar/prevenção & controle , Surtos de Doenças , Humanos , Pandemias , Infecções por Vírus Respiratório Sincicial/epidemiologia , Vírus Sincicial Respiratório Humano/genética
8.
iScience ; 25(5): 104276, 2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35573195

RESUMO

To improve the identification and management of viral respiratory infections, we established a clinical and virologic surveillance program for pediatric patients fulfilling pre-defined case criteria of influenza-like illness and viral respiratory infections. The program resulted in a cohort comprising 6,073 patients (56% male, median age 1.6 years, range 0-18.8 years), where every patient was assessed with a validated disease severity score at the point-of-care using the ViVI ScoreApp. We used machine learning and agnostic feature selection to identify characteristic clinical patterns. We tested all patients for human adenoviruses, 571 (9%) were positive. Adenovirus infections were particularly common and mild in children ≥1 month of age but rare and potentially severe in neonates: with lower airway involvement, disseminated disease, and a 50% mortality rate (n = 2/4). In one fatal case, we discovered a novel virus: HAdV-80. Standardized surveillance leveraging digital technology helps to identify characteristic clinical patterns, risk factors, and emerging pathogens.

9.
J Hepatol ; 76(1): 46-52, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34461207

RESUMO

BACKGROUND AND AIMS: Immunocompromised patients are at risk of chronic hepatitis E which can be acquired by blood transfusions. Currently, screening of blood donors (BDs) for HEV RNA with a limit of detection (LOD) of 2,000 IU/ml is required in Germany. However, this may result in up to 440,000 IU of HEV RNA in blood products depending on their plasma volume. We studied the residual risk of transfusion-transmitted (tt) HEV infection when an LOD of 2,000 IU/ml is applied. METHODS: Highly sensitive individual donor testing for HEV RNA on the Grifols Procleix Panther system (LOD 7.89 IU/ml) was performed. HEV loads were quantified by real-time PCR. RESULTS: Of 16,236 donors, 31 (0.19%) were HEV RNA positive. Three BDs had viral loads between 710 and 2,000 IU/ml, which pose a significant risk of tt hepatitis E with any type of blood product. Eight BDs had viral loads of >32 to 710 IU/ml, which pose a risk of tt hepatitis E with platelet or plasma transfusions because of their higher plasma volume compared to red blood cell concentrates. Eight of these 11 potentially infectious BDs were seronegative for HEV, indicating a recent infection. Only 8 of 31 donors had viral loads >2,000 IU/ml that would also have been detected by the required screening procedure and 12 had very low HEV loads (<32 IU/ml). CONCLUSIONS: Screening of BDs with an LOD of 2,000 IU/ml reduced the risk of tt HEV infection by about 73% for red blood cell concentrates but by just 42% for platelet and fresh frozen plasma transfusions. Single donor screening (LOD <32 IU/ml) should lead to an almost 100% risk reduction. LAY SUMMARY: Immunocompromised patients, such as solid organ or hematopoietic stem cell recipients, are at risk of chronic hepatitis E, which can be acquired via blood transfusions. The risk of transfusion-transmitted hepatitis E in these patients may not be sufficiently controlled by (mini-)pool hepatitis E virus RNA screening of blood donors. Single donor screening should be considered to improve the safety of blood products.


Assuntos
Transfusão de Sangue/normas , Hepatite E/transmissão , Reação Transfusional/diagnóstico , Adulto , Transfusão de Sangue/métodos , Transfusão de Sangue/estatística & dados numéricos , Seleção do Doador/normas , Seleção do Doador/estatística & dados numéricos , Feminino , Alemanha , Hepatite E/sangue , Vírus da Hepatite E/metabolismo , Vírus da Hepatite E/patogenicidade , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Medição de Risco/métodos , Medição de Risco/estatística & dados numéricos , Estatísticas não Paramétricas , Reação Transfusional/fisiopatologia
10.
Graefes Arch Clin Exp Ophthalmol ; 260(1): 173-180, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34406500

RESUMO

PURPOSE: Epidemic keratoconjunctivitis (EKC) is one of the most severe ocular viral infections. The aim of this interruptive time series study was to quantitatively evaluate the effectiveness of a hygienic EKC outbreak management concept developed in our ophthalmological department. METHODS: All patients with suspected EKC in the period from August to November 2018 were included in the study. Data were retrospectively collected from the patient's medical documents and records. The disease was diagnosed clinically and confirmed by virus detection through polymerase chain reaction (PCR) from conjunctival swabs. With the beginning of the epidemic, an outbreak management plan was implemented to reduce the nosocomial spread. RESULTS: The outbreak lasted 77 days (20th August 2018 to 4th November 2018) and affected a total of 120 patients. This corresponds to a mean of 1.5 patients per outbreak day. The median age was 58 [1-92] years. Of all patients, 61 (50.8%) were female. Conjunctival swabs were collected in 100/120 (83.3%) cases, the adenovirus being detected in all positive smears (63/63, 100%). The implementation of our outbreak management plan reduced significantly the number of EKC cases per outbreak day and resulted in a reduction of the basic reproduction number by a factor of 2.2. CONCLUSION: The detection of EKC together with the immediate implementation of hygienic outbreak measures can significantly reduce the spread of infection. The implementation of a strict outbreak management concept can significantly reduce the number of EKC cases, thus avoiding possible complications and therefore unnecessary health-related costs.


Assuntos
Infecções por Adenovirus Humanos , Conjuntivite Viral , Infecção Hospitalar , Ceratoconjuntivite , Surtos de Doenças , Feminino , Humanos , Ceratoconjuntivite/diagnóstico , Ceratoconjuntivite/tratamento farmacológico , Ceratoconjuntivite/epidemiologia , Pessoa de Meia-Idade , Estudos Retrospectivos
11.
J Clin Virol ; 142: 104932, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34333392

RESUMO

OBJECTIVES: Quantification of plasma hepatitis D virus (HDV) RNA is the essential tool for patient management under antiviral therapy. The aim of this European multicenter study was to improve the comparability of quantitative results reported by different laboratories using the CE/IVD-labeled RoboGene HDV RNA Quantification Kit 2.0 (Roboscreen GmbH) with different manual or automated nucleic acid extraction protocols/platforms and amplification/detection devices. METHODS: For harmonization of HDV RNA concentrations obtained by different protocols, correction factors (CF) were determined using the 1st WHO International Standard for HDV RNA. The limit of detection (LOD) and accuracy were determined for each protocol by using reference material. Furthermore, clinical samples were analyzed and results compared. RESULTS: The CF ranged from 20 to 1,870 depending on the protocol used. The LOD was found between 4 and 450 IU/ml. When accuracy was tested, external quality control (EQC) samples containing low HDV RNA concentrations were not detected by those protocols with higher LODs. For EQC samples, the maximum standard deviation of HDV RNA concentrations was found to be 0.53 log10 IU/ml, for clinical samples 0.87 log10 IU/mL. CONCLUSION: To ensure reliability in quantification of HDV RNA, any modification of the extraction and amplification/detection protocol validated by the manufacturer requires revalidation. With the 1st WHO International Standard for HDV RNA, the CF could easily be calculated leading to harmonization of quantitative results. This warrants both accurate monitoring of response to existing anti-HDV treatment and comparability of study results investigating novel anti-HDV drugs.


Assuntos
Hepatite D , Preparações Farmacêuticas , Hepatite D/diagnóstico , Hepatite D/tratamento farmacológico , Vírus Delta da Hepatite/genética , Humanos , RNA Viral , Reprodutibilidade dos Testes , Carga Viral
12.
mBio ; 12(3)2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33947766

RESUMO

Interferon-stimulated gene products (ISGs) play a crucial role in early infection control. The ISG zinc finger CCCH-type antiviral protein 1 (ZAP/ZC3HAV1) antagonizes several RNA viruses by binding to CG-rich RNA sequences, whereas its effect on DNA viruses is less well understood. Here, we decipher the role of ZAP in the context of human cytomegalovirus (HCMV) infection, a ß-herpesvirus that is associated with high morbidity in immunosuppressed individuals and newborns. We show that expression of the two major isoforms of ZAP, ZAP-S and ZAP-L, is induced during HCMV infection and that both negatively affect HCMV replication. Transcriptome and proteome analyses demonstrated that the expression of ZAP results in reduced viral mRNA and protein levels and decelerates the progression of HCMV infection. Metabolic RNA labeling combined with high-throughput sequencing (SLAM-seq) revealed that most of the gene expression changes late in infection result from the general attenuation of HCMV. Furthermore, at early stages of infection, ZAP restricts HCMV by destabilizing a distinct subset of viral mRNAs, particularly those from the previously uncharacterized UL4-UL6 HCMV gene locus. Through enhanced cross-linking immunoprecipitation and sequencing analysis (eCLIP-seq), we identified the transcripts expressed from this HCMV locus as the direct targets of ZAP. Moreover, our data show that ZAP preferentially recognizes not only CG, but also other cytosine-rich sequences, thereby expanding its target specificity. In summary, this report is the first to reveal direct targets of ZAP during HCMV infection, which strongly indicates that transcripts from the UL4-UL6 locus may play an important role for HCMV replication.IMPORTANCE Viral infections have a large impact on society, leading to major human and economic losses and even global instability. So far, many viral infections, including human cytomegalovirus (HCMV) infection, are treated with a small repertoire of drugs, often accompanied by the occurrence of resistant mutants. There is no licensed HCMV vaccine in sight to protect those most at risk, particularly immunocompromised individuals or pregnant women who might otherwise transmit the virus to the fetus. Thus, the identification of novel intervention strategies is urgently required. In this study, we show that ZAP decelerates the viral gene expression cascade, presumably by selectively handpicking a distinct set of viral transcripts for degradation. Our study illustrates the potent role of ZAP as an HCMV restriction factor and sheds light on a possible role for UL4 and/or UL5 early during infection, paving a new avenue for the exploration of potential targets for novel therapies.


Assuntos
Citomegalovirus/genética , Interações entre Hospedeiro e Microrganismos/genética , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Proteínas do Envelope Viral/metabolismo , Proteínas Virais/metabolismo , Linhagem Celular , Células Cultivadas , Citomegalovirus/fisiologia , Fibroblastos/virologia , Células HEK293 , Humanos , Isoformas de Proteínas/genética , Proteínas de Ligação a RNA/farmacologia , Proteínas do Envelope Viral/genética , Proteínas Virais/genética , Replicação Viral/genética
13.
Blood Adv ; 5(9): 2294-2304, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33929500

RESUMO

Next-generation sequencing (NGS)-based measurable residual disease (MRD) monitoring in patients with acute myeloid leukemia (AML) is widely applicable and prognostic prior to allogeneic hematopoietic cell transplantation (alloHCT). We evaluated the prognostic role of clonal hematopoiesis-associated DNMT3A, TET2, and ASXL1 (DTA) and non-DTA mutations for MRD monitoring post-alloHCT to refine MRD marker selection. Of 154 patients with AML, 138 (90%) had at least one mutation at diagnosis, which were retrospectively monitored by amplicon-based error-corrected NGS on day 90 and/or day 180 post-alloHCT. MRD was detected in 34 patients on day 90 and/or day 180 (25%). The rate of MRD positivity was similar when DTA and non-DTA mutations were considered separately (17.6% vs 19.8%). DTA mutations had no prognostic impact on cumulative incidence of relapse, relapse-free survival, or overall survival in our study and were removed from further analysis. In the remaining 131 patients with at least 1 non-DTA mutation, clinical and transplantation-associated characteristics were similarly distributed between MRD-positive and MRD-negative patients. In multivariate analysis, MRD positivity was an independent adverse predictor of cumulative incidence of relapse, relapse-free survival, and overall survival but not of nonrelapse mortality. The prognostic effect was independent of different cutoffs (above limit of detection, 0.1% and 1% variant allele frequency). MRD log-reduction between diagnosis and post-alloHCT assessment had no prognostic value. MRD status post-alloHCT had the strongest impact in patients who were MRD positive prior to alloHCT. In conclusion, non-DTA mutations are prognostic NGS-MRD markers post-alloHCT, whereas the prognostic role of DTA mutations in the posttransplant setting remains open.


Assuntos
Leucemia Mieloide Aguda , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Mutação , Neoplasia Residual , Estudos Retrospectivos
14.
J Med Virol ; 93(7): 4438-4445, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33350484

RESUMO

The hologic panther fusion (PF) platform provides fully automated CE marked diagnostics for respiratory viruses, including the recently discovered severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) by a transcription mediated amplification (TMA) assay, but not for the endemic human coronaviruses (hCoV). Therefore, a laboratory developed test (LDT) comprising a multiplexed reverse transcription polymerase chain reaction (RT-PCR) protocol that detects and differentiates the four hCoV NL63, 229E, HKU1, and OC43 was adapted on the PF. The novel CE marked Aptima SARS-CoV-2 TMA and the LDT for hCoV were validated with 321 diagnostic specimens from the upper and lower respiratory tract in comparison to two SARS-CoV-2 RT-PCRs (PF E-gene RT-PCR and genesig RT-PCR, 157 specimens) or the R-GENE hCoV/hParaFlu RT-PCR (164 specimens), respectively. For the endemic hCoV, results were 96.3% concordant with two specimens discordantly positive in the PF and four specimens discordantly positive in the R-GENE assay. All discordantly positive samples had Ct values between 33 and 39. The PF hCoV LDT identified 23 hCoV positive specimens as NL63, 15 as 229E, 15 as HKU1, and 25 as OC43. The Aptima SARS-CoV-2 TMA gave 99.4% concordant results compared to the consensus results with a single specimen discordantly positive. Moreover, 36 samples from proficiency testing panels were detected and typed correctly by both novel methods. In conclusion, the SARS-CoV-2 TMA and the LDT for hCoV enhanced the diagnostic spectrum of the PF for all coronaviruses circulating globally for a multitude of diagnostic materials from the upper and lower respiratory tract.


Assuntos
Alphacoronavirus/genética , COVID-19/diagnóstico , Coronavirus Humano 229E/genética , Coronavirus Humano NL63/genética , Coronavirus Humano OC43/genética , SARS-CoV-2/genética , Humanos , Técnicas de Amplificação de Ácido Nucleico/métodos , Sistema Respiratório/virologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos
15.
Int J Mol Sci ; 21(17)2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32887347

RESUMO

Recently an increasing number of new adenovirus types associated with type-dependent pathogenicity have been identified. However, identification of these clinical isolates represents the very first step to characterize novel pathogens. For deeper analyses, these adenoviruses need to be further characterized in basic virology experiments or they could be applied in translational research. To achieve this goal, it is essential to get genetic access and to enable genetic modification of these novel adenovirus genomes (deletion, insertion, and mutation). Here we demonstrate a high-throughput approach to get genetic access to new adenoviruses via homologous recombination. We first defined the cloning conditions regarding homology arm-length and input adenoviral genome amounts. Then we cloned four naturally occurring adenoviruses (Ad70, Ad73, Ad74, and Ad75) into easy-to-manipulate plasmids and genetically modified them by reporter gene insertion. Three recombinant adenoviruses (Ad70, Ad73, and Ad74) containing a reporter cassette were successfully reconstituted. These novel reporter-labeled adenoviruses were further characterized using the inserted luciferase reporter with respect to receptor usage, presence of anti-adenovirus antibodies, and tropism in vitro. The identified receptor usage, the relatively low prevalence of anti-adenovirus antibodies, and the various cancer cell line transduction pattern are important features of these new pathogens providing essential information for their therapeutic application.


Assuntos
Adenovírus Humanos/classificação , Adenovírus Humanos/genética , Clonagem Molecular/métodos , Genes Reporter , Vetores Genéticos/genética , Genoma Viral , Ensaios de Triagem em Larga Escala , Recombinação Homóloga , Humanos
16.
Artigo em Inglês | MEDLINE | ID: mdl-32612959

RESUMO

Human cytomegalovirus (HCMV) is the most frequent cause of opportunistic viral infection following transplantation. Viral factors of potential clinical importance include the selection of mutants resistant to antiviral drugs and the occurrence of infections involving multiple HCMV strains. These factors are typically addressed by analyzing relevant HCMV genes by PCR and Sanger sequencing, which involves independent assays of limited sensitivity. To assess the dynamics of viral populations with high sensitivity, we applied high-throughput sequencing coupled with HCMV-adapted target enrichment to samples collected longitudinally from 11 transplant recipients (solid organ, n = 9, and allogeneic hematopoietic stem cell, n = 2). Only the latter presented multiple-strain infections. Four cases presented resistance mutations (n = 6), two (A594V and L595S) at high (100%) and four (V715M, V781I, A809V, and T838A) at low (<25%) frequency. One allogeneic hematopoietic stem cell transplant recipient presented up to four resistance mutations, each at low frequency. The use of high-throughput sequencing to monitor mutations and strain composition in people at risk of HCMV disease is of potential value in helping clinicians implement the most appropriate therapy.


Assuntos
Infecções por Citomegalovirus , Citomegalovirus , Antivirais/farmacologia , Antivirais/uso terapêutico , Citomegalovirus/genética , Infecções por Citomegalovirus/tratamento farmacológico , DNA Viral , Farmacorresistência Viral , Ganciclovir/uso terapêutico , Humanos
18.
J Med Microbiol ; 69(3): 427-435, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32118531

RESUMO

Introduction. Diagnosis of acute respiratory infections (ARIs) can be facilitated by the Panther Fusion (PF) automatic, random access PCR system for the detection of influenzavirus A (Flu A) and B (Flu B), parainfluenzavirus (Paraflu), respiratory syncytial virus (RSV), human metapneumovirus (hMPV), rhinovirus (RV) and human adenovirus (AdV) in nasopharyngeal swabs.Aim. To evaluate the performance of PF in comparison with established methods, including subsets of (1) lower respiratory tract (LRT) specimens and (2) upper respiratory tract (URT) hygiene screening specimens of patients without ARI symptoms.Methodology. The performance characteristics of PF were compared with bioMérieux R-Gene and laboratory-developed PCR tests (LDTs). Overall, 1544 specimens with 6658 individual diagnostic requests were analysed.Results. The overall concordances of PF and LDTs for Flu A, Flu B and AdV were 98.4, 99.9 and 96.1%, respectively; by re-testing of discrepant specimens concordances increased to 99.4, 99.9 and 98.0%, respectively. Initial concordances of PF and R-Gene assays for RSV, Paraflu, hMPV and RV were 98.4, 96.3, 99.3 and 96.0%, respectively, and retest concordances were 99.7, 97.9, 99.9 and 98.9%, respectively. No differences to the overall performance were found for the subgroups of LRT and hygiene screening specimens. PCR cycle threshold (Ct) values correlated very well between methods, indicating that a semi-quantitative diagnostic approach using Ct values (e.g. highly vs. weakly positive) could augment the diagnostic information.Conclusion. PF performed similar to R-Gene and LDTs not only for its intended use but also for LRT and hygiene screening specimens with shorter hands-on and turnaround times.


Assuntos
Reação em Cadeia da Polimerase em Tempo Real/métodos , Infecções Respiratórias/diagnóstico , Vírus/isolamento & purificação , Doença Aguda , Humanos , Higiene , Nasofaringe/virologia , Estudos Prospectivos , Infecções Respiratórias/virologia , Vírus/genética
20.
Virchows Arch ; 477(1): 73-81, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32025822

RESUMO

Villitis of unknown etiology (VUE) and chronic deciduitis with plasma cells (CD) are supposed to be non infectious placental lesions caused by a pathologic immune reaction similar to a host versus graft mechanism. In some investigations, infection of human trophoblastic cells with human papilloma virus (HPV) has been described, and a relationship with miscarriage, preeclampsia, and chronic inflammatory placental lesions has been suspected. Infection with enterovirus, especially Coxsackievirus, has been observed in cases with spontaneous abortion and adverse perinatal outcome, respectively. We investigated 20 cases with VUE and 30 cases with chronic deciduitis with plasma cells. The placenta specimens were analyzed for expression of HPV capsid protein by immunohistochemistry, for presence of HPV DNA via polymerase chain reaction (PCR), and for presence of enterovirus mRNA using RT-PCR, respectively. VUE was associated with maternal diseases: atopic lesions in 21%, other autoimmune diseases in 15.5%, and obesity in 31.5%, respectively. Birth weight below the 10th percentile was detected in 63% of the cases with VUE. Chronic deciduitis was associated with preterm labor and preterm premature rupture of membranes (26%). Intrauterine fetal demise occurred in 5 cases with CD (18.5%). HPV DNA, HPV capsid protein, and enterovirus mRNA were not detected in all investigated VUE or CD cases. Our investigations show that a causal role for enterovirus and human papilloma virus in the development of VUE and CD is unlikely. Therefore, HPV vaccination is unlikely to reduce the incidence of VUE and CD in the future.


Assuntos
Corioamnionite/etiologia , Vilosidades Coriônicas/patologia , Papillomaviridae/patogenicidade , Placenta/virologia , Adulto , Corioamnionite/patologia , Corioamnionite/virologia , Infecções por Enterovirus/etiologia , Feminino , Humanos , Recém-Nascido , Placenta/patologia , Doenças Placentárias/etiologia , Doenças Placentárias/patologia , Gravidez , Trofoblastos/patologia , Trofoblastos/virologia
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