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1.
Cell ; 182(4): 843-854.e12, 2020 08 20.
Article in English | MEDLINE | ID: mdl-32673567

ABSTRACT

The SARS-CoV-2 pandemic has unprecedented implications for public health, social life, and the world economy. Because approved drugs and vaccines are limited or not available, new options for COVID-19 treatment and prevention are in high demand. To identify SARS-CoV-2-neutralizing antibodies, we analyzed the antibody response of 12 COVID-19 patients from 8 to 69 days after diagnosis. By screening 4,313 SARS-CoV-2-reactive B cells, we isolated 255 antibodies from different time points as early as 8 days after diagnosis. Of these, 28 potently neutralized authentic SARS-CoV-2 with IC100 as low as 0.04 µg/mL, showing a broad spectrum of variable (V) genes and low levels of somatic mutations. Interestingly, potential precursor sequences were identified in naive B cell repertoires from 48 healthy individuals who were sampled before the COVID-19 pandemic. Our results demonstrate that SARS-CoV-2-neutralizing antibodies are readily generated from a diverse pool of precursors, fostering hope for rapid induction of a protective immune response upon vaccination.


Subject(s)
Antibodies, Neutralizing/isolation & purification , Antibodies, Viral/isolation & purification , Coronavirus Infections/immunology , Pneumonia, Viral/immunology , Antibodies, Neutralizing/genetics , Antibodies, Neutralizing/immunology , Antibodies, Viral/genetics , Antibodies, Viral/immunology , B-Lymphocytes/immunology , Betacoronavirus/immunology , COVID-19 , Humans , Immunoglobulin Variable Region/genetics , Immunoglobulin Variable Region/immunology , Immunologic Memory , Longitudinal Studies , Pandemics , SARS-CoV-2 , Somatic Hypermutation, Immunoglobulin
2.
Immunity ; 55(2): 341-354.e7, 2022 02 08.
Article in English | MEDLINE | ID: mdl-34990590

ABSTRACT

The high genetic diversity of hepatitis C virus (HCV) complicates effective vaccine development. We screened a cohort of 435 HCV-infected individuals and found that 2%-5% demonstrated outstanding HCV-neutralizing activity. From four of these patients, we isolated 310 HCV antibodies, including neutralizing antibodies with exceptional breadth and potency. High neutralizing activity was enabled by the use of the VH1-69 heavy-chain gene segment, somatic mutations within CDRH1, and CDRH2 hydrophobicity. Structural and mutational analyses revealed an important role for mutations replacing the serines at positions 30 and 31, as well as the presence of neutral and hydrophobic residues at the tip of the CDRH3. Based on these characteristics, we computationally created a de novo antibody with a fully synthetic VH1-69 heavy chain that efficiently neutralized multiple HCV genotypes. Our findings provide a deep understanding of the generation of broadly HCV-neutralizing antibodies that can guide the design of effective vaccine candidates.


Subject(s)
Broadly Neutralizing Antibodies/genetics , Hepacivirus/immunology , Hepatitis C Antibodies/genetics , B-Lymphocytes/immunology , Broadly Neutralizing Antibodies/chemistry , Broadly Neutralizing Antibodies/immunology , Complementarity Determining Regions/chemistry , Complementarity Determining Regions/genetics , Complementarity Determining Regions/immunology , Epitopes , Female , Genotype , Hepacivirus/genetics , Hepatitis C/immunology , Hepatitis C Antibodies/chemistry , Hepatitis C Antibodies/immunology , Humans , Immunoglobulin Heavy Chains/chemistry , Immunoglobulin Heavy Chains/genetics , Immunoglobulin Heavy Chains/immunology , Male , Middle Aged , Mutation , Viral Envelope Proteins/chemistry , Viral Envelope Proteins/immunology
4.
PLoS Comput Biol ; 20(6): e1012131, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38848436

ABSTRACT

Immunization through repeated direct venous inoculation of Plasmodium falciparum (Pf) sporozoites (PfSPZ) under chloroquine chemoprophylaxis, using the PfSPZ Chemoprophylaxis Vaccine (PfSPZ-CVac), induces high-level protection against controlled human malaria infection (CHMI). Humoral and cellular immunity contribute to vaccine efficacy but only limited information about the implicated Pf-specific antigens is available. Here, we examined Pf-specific antibody profiles, measured by protein arrays representing the full Pf proteome, of 40 placebo- and PfSPZ-immunized malaria-naïve volunteers from an earlier published PfSPZ-CVac dose-escalation trial. For this purpose, we both utilized and adapted supervised machine learning methods to identify predictive antibody profiles at two different time points: after immunization and before CHMI. We developed an adapted multitask support vector machine (SVM) approach and compared it to standard methods, i.e. single-task SVM, regularized logistic regression and random forests. Our results show, that the multitask SVM approach improved the classification performance to discriminate the protection status based on the underlying antibody-profiles while combining time- and dose-dependent data in the prediction model. Additionally, we developed the new fEature diStance exPlainabilitY (ESPY) method to quantify the impact of single antigens on the non-linear multitask SVM model and make it more interpretable. In conclusion, our multitask SVM model outperforms the studied standard approaches in regard of classification performance. Moreover, with our new explanation method ESPY, we were able to interpret the impact of Pf-specific antigen antibody responses that predict sterile protective immunity against CHMI after immunization. The identified Pf-specific antigens may contribute to a better understanding of immunity against human malaria and may foster vaccine development.


Subject(s)
Antibodies, Protozoan , Machine Learning , Malaria Vaccines , Malaria, Falciparum , Plasmodium falciparum , Malaria Vaccines/immunology , Humans , Plasmodium falciparum/immunology , Malaria, Falciparum/prevention & control , Malaria, Falciparum/immunology , Malaria, Falciparum/parasitology , Antibodies, Protozoan/immunology , Antibodies, Protozoan/blood , Vaccine Efficacy , Support Vector Machine , Computational Biology/methods
5.
Bioinformatics ; 39(39 Suppl 1): i76-i85, 2023 06 30.
Article in English | MEDLINE | ID: mdl-37387152

ABSTRACT

MOTIVATION: The size of available omics datasets is steadily increasing with technological advancement in recent years. While this increase in sample size can be used to improve the performance of relevant prediction tasks in healthcare, models that are optimized for large datasets usually operate as black boxes. In high-stakes scenarios, like healthcare, using a black-box model poses safety and security issues. Without an explanation about molecular factors and phenotypes that affected the prediction, healthcare providers are left with no choice but to blindly trust the models. We propose a new type of artificial neural network, named Convolutional Omics Kernel Network (COmic). By combining convolutional kernel networks with pathway-induced kernels, our method enables robust and interpretable end-to-end learning on omics datasets ranging in size from a few hundred to several hundreds of thousands of samples. Furthermore, COmic can be easily adapted to utilize multiomics data. RESULTS: We evaluated the performance capabilities of COmic on six different breast cancer cohorts. Additionally, we trained COmic models on multiomics data using the METABRIC cohort. Our models performed either better or similar to competitors on both tasks. We show how the use of pathway-induced Laplacian kernels opens the black-box nature of neural networks and results in intrinsically interpretable models that eliminate the need for post hoc explanation models. AVAILABILITY AND IMPLEMENTATION: Datasets, labels, and pathway-induced graph Laplacians used for the single-omics tasks can be downloaded at https://ibm.ent.box.com/s/ac2ilhyn7xjj27r0xiwtom4crccuobst/folder/48027287036. While datasets and graph Laplacians for the METABRIC cohort can be downloaded from the above mentioned repository, the labels have to be downloaded from cBioPortal at https://www.cbioportal.org/study/clinicalData?id=brca\_metabric. COmic source code as well as all scripts necessary to reproduce the experiments and analysis are publicly available at https://github.com/jditz/comics.


Subject(s)
Algorithms , Neural Networks, Computer , Software , Multiomics , Phenotype
6.
Bioinformatics ; 39(39 Suppl 1): i86-i93, 2023 06 30.
Article in English | MEDLINE | ID: mdl-37387133

ABSTRACT

MOTIVATION: Machine learning methods can be used to support scientific discovery in healthcare-related research fields. However, these methods can only be reliably used if they can be trained on high-quality and curated datasets. Currently, no such dataset for the exploration of Plasmodium falciparum protein antigen candidates exists. The parasite P.falciparum causes the infectious disease malaria. Thus, identifying potential antigens is of utmost importance for the development of antimalarial drugs and vaccines. Since exploring antigen candidates experimentally is an expensive and time-consuming process, applying machine learning methods to support this process has the potential to accelerate the development of drugs and vaccines, which are needed for fighting and controlling malaria. RESULTS: We developed PlasmoFAB, a curated benchmark that can be used to train machine learning methods for the exploration of P.falciparum protein antigen candidates. We combined an extensive literature search with domain expertise to create high-quality labels for P.falciparum specific proteins that distinguish between antigen candidates and intracellular proteins. Additionally, we used our benchmark to compare different well-known prediction models and available protein localization prediction services on the task of identifying protein antigen candidates. We show that available general-purpose services are unable to provide sufficient performance on identifying protein antigen candidates and are outperformed by our models that were trained on this tailored data. AVAILABILITY AND IMPLEMENTATION: PlasmoFAB is publicly available on Zenodo with DOI 10.5281/zenodo.7433087. Furthermore, all scripts that were used in the creation of PlasmoFAB and the training and evaluation of machine learning models are open source and publicly available on GitHub here: https://github.com/msmdev/PlasmoFAB.


Subject(s)
Benchmarking , Malaria, Falciparum , Humans , Plasmodium falciparum , Machine Learning , Malaria, Falciparum/diagnosis , Protein Transport
7.
Bioinformatics ; 39(1)2023 01 01.
Article in English | MEDLINE | ID: mdl-36571499

ABSTRACT

MOTIVATION: We present a multi-sequence generalization of Variational Information Bottleneck and call the resulting model Attentive Variational Information Bottleneck (AVIB). Our AVIB model leverages multi-head self-attention to implicitly approximate a posterior distribution over latent encodings conditioned on multiple input sequences. We apply AVIB to a fundamental immuno-oncology problem: predicting the interactions between T-cell receptors (TCRs) and peptides. RESULTS: Experimental results on various datasets show that AVIB significantly outperforms state-of-the-art methods for TCR-peptide interaction prediction. Additionally, we show that the latent posterior distribution learned by AVIB is particularly effective for the unsupervised detection of out-of-distribution amino acid sequences. AVAILABILITY AND IMPLEMENTATION: The code and the data used for this study are publicly available at: https://github.com/nec-research/vibtcr. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Subject(s)
Peptides , Software , Amino Acid Sequence , Receptors, Antigen, T-Cell/genetics
8.
PLoS Comput Biol ; 19(3): e1010959, 2023 03.
Article in English | MEDLINE | ID: mdl-36877742

ABSTRACT

Missense variants in genes encoding ion channels are associated with a spectrum of severe diseases. Variant effects on biophysical function correlate with clinical features and can be categorized as gain- or loss-of-function. This information enables a timely diagnosis, facilitates precision therapy, and guides prognosis. Functional characterization presents a bottleneck in translational medicine. Machine learning models may be able to rapidly generate supporting evidence by predicting variant functional effects. Here, we describe a multi-task multi-kernel learning framework capable of harmonizing functional results and structural information with clinical phenotypes. This novel approach extends the human phenotype ontology towards kernel-based supervised machine learning. Our gain- or loss-of-function classifier achieves high performance (mean accuracy 0.853 SD 0.016, mean AU-ROC 0.912 SD 0.025), outperforming both conventional baseline and state-of-the-art methods. Performance is robust across different phenotypic similarity measures and largely insensitive to phenotypic noise or sparsity. Localized multi-kernel learning offered biological insight and interpretability by highlighting channels with implicit genotype-phenotype correlations or latent task similarity for downstream analysis.


Subject(s)
Ion Channels , Machine Learning , Humans , Phenotype , Ion Channels/genetics , Genetic Association Studies , Supervised Machine Learning
9.
PLoS Comput Biol ; 19(12): e1010355, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38127856

ABSTRACT

The mechanisms triggering the human immunodeficiency virus type I (HIV-1) to switch the coreceptor usage from CCR5 to CXCR4 during the course of infection are not entirely understood. While low CD4+ T cell counts are associated with CXCR4 usage, a predominance of CXCR4 usage with still high CD4+ T cell counts remains puzzling. Here, we explore the hypothesis that viral adaptation to the human leukocyte antigen (HLA) complex, especially to the HLA class II alleles, contributes to the coreceptor switch. To this end, we sequence the viral gag and env protein with corresponding HLA class I and II alleles of a new cohort of 312 treatment-naive, subtype C, chronically-infected HIV-1 patients from South Africa. To estimate HLA adaptation, we develop a novel computational approach using Bayesian generalized linear mixed models (GLMMs). Our model allows to consider the entire HLA repertoire without restricting the model to pre-learned HLA-polymorphisms. In addition, we correct for phylogenetic relatedness of the viruses within the model itself to account for founder effects. Using our model, we observe that CXCR4-using variants are more adapted than CCR5-using variants (p-value = 1.34e-2). Additionally, adapted CCR5-using variants have a significantly lower predicted false positive rate (FPR) by the geno2pheno[coreceptor] tool compared to the non-adapted CCR5-using variants (p-value = 2.21e-2), where a low FPR is associated with CXCR4 usage. Consequently, estimating HLA adaptation can be an asset in predicting not only coreceptor usage, but also an approaching coreceptor switch in CCR5-using variants. We propose the usage of Bayesian GLMMs for modeling virus-host adaptation in general.


Subject(s)
HIV Infections , HIV-1 , Humans , Receptors, CCR5/genetics , Receptors, CCR5/metabolism , Phylogeny , Bayes Theorem , Receptors, CXCR4/genetics , Receptors, CXCR4/metabolism , Histocompatibility Antigens
10.
Nature ; 561(7724): 479-484, 2018 09.
Article in English | MEDLINE | ID: mdl-30258136

ABSTRACT

Individuals infected with HIV-1 require lifelong antiretroviral therapy, because interruption of treatment leads to rapid rebound viraemia. Here we report on a phase 1b clinical trial in which a combination of 3BNC117 and 10-1074, two potent monoclonal anti-HIV-1 broadly neutralizing antibodies that target independent sites on the HIV-1 envelope spike, was administered during analytical treatment interruption. Participants received three infusions of 30 mg kg-1 of each antibody at 0, 3 and 6 weeks. Infusions of the two antibodies were generally well-tolerated. The nine enrolled individuals with antibody-sensitive latent viral reservoirs maintained suppression for between 15 and more than 30 weeks (median of 21 weeks), and none developed viruses that were resistant to both antibodies. We conclude that the combination of the anti-HIV-1 monoclonal antibodies 3BNC117 and 10-1074 can maintain long-term suppression in the absence of antiretroviral therapy in individuals with antibody-sensitive viral reservoirs.


Subject(s)
Antibodies, Monoclonal/therapeutic use , Antibodies, Neutralizing/therapeutic use , HIV Antibodies/therapeutic use , HIV Infections/drug therapy , HIV Infections/immunology , HIV-1/immunology , Virus Latency/immunology , Adolescent , Adult , Aged , Anti-HIV Agents/administration & dosage , Anti-HIV Agents/immunology , Anti-HIV Agents/therapeutic use , Antibodies, Monoclonal/administration & dosage , Antibodies, Monoclonal/adverse effects , Antibodies, Monoclonal/immunology , Antibodies, Monoclonal, Humanized , Antibodies, Neutralizing/administration & dosage , Antibodies, Neutralizing/adverse effects , Antibodies, Neutralizing/immunology , Binding Sites, Antibody , Broadly Neutralizing Antibodies , Carrier State/drug therapy , Carrier State/immunology , Carrier State/virology , Drug Combinations , Drug Resistance, Viral , Female , HIV Antibodies/administration & dosage , HIV Antibodies/adverse effects , HIV Antibodies/immunology , HIV Envelope Protein gp160/immunology , HIV Infections/virology , HIV-1/isolation & purification , Historically Controlled Study , Humans , Infusions, Intravenous , Male , Middle Aged , Phylogeny , Viremia/drug therapy , Viremia/immunology , Viremia/prevention & control , Viremia/virology , Virus Activation/immunology , Young Adult
11.
Bioinformatics ; 38(8): 2202-2210, 2022 04 12.
Article in English | MEDLINE | ID: mdl-35150254

ABSTRACT

MOTIVATION: Diagnosis and treatment decisions on genomic data have become widespread as the cost of genome sequencing decreases gradually. In this context, disease-gene association studies are of great importance. However, genomic data are very sensitive when compared to other data types and contains information about individuals and their relatives. Many studies have shown that this information can be obtained from the query-response pairs on genomic databases. In this work, we propose a method that uses secure multi-party computation to query genomic databases in a privacy-protected manner. The proposed solution privately outsources genomic data from arbitrarily many sources to the two non-colluding proxies and allows genomic databases to be safely stored in semi-honest cloud environments. It provides data privacy, query privacy and output privacy by using XOR-based sharing and unlike previous solutions, it allows queries to run efficiently on hundreds of thousands of genomic data. RESULTS: We measure the performance of our solution with parameters similar to real-world applications. It is possible to query a genomic database with 3 000 000 variants with five genomic query predicates under 400 ms. Querying 1 048 576 genomes, each containing 1 000 000 variants, for the presence of five different query variants can be achieved approximately in 6 min with a small amount of dedicated hardware and connectivity. These execution times are in the right range to enable real-world applications in medical research and healthcare. Unlike previous studies, it is possible to query multiple databases with response times fast enough for practical application. To the best of our knowledge, this is the first solution that provides this performance for querying large-scale genomic data. AVAILABILITY AND IMPLEMENTATION: https://gitlab.com/DIFUTURE/privacy-preserving-variant-queries. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Subject(s)
Computer Security , Privacy , Humans , Genomics , Databases, Factual
12.
BMC Infect Dis ; 23(1): 690, 2023 Oct 16.
Article in English | MEDLINE | ID: mdl-37845624

ABSTRACT

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS CoV-2), the virus responsible for coronavirus disease 2019 (COVID-19), can lead to hospitalisation, particularly in elderly, immunocompromised, and non-vaccinated or partially vaccinated individuals. Although vaccination provides protection, the duration of this protection wanes over time. Additional doses can restore immunity, but the influence of viral variants, specific sequences, and vaccine-induced immune responses on disease severity remains unclear. Moreover, the efficacy of therapeutic interventions during hospitalisation requires further investigation. The study aims to analyse the clinical course of COVID-19 in hospitalised patients, taking into account SARS-CoV-2 variants, viral sequences, and the impact of different vaccines. The primary outcome is all-cause in-hospital mortality, while secondary outcomes include admission to intensive care unit and length of stay, duration of hospitalisation, and the level of respiratory support required. METHODS: This ongoing multicentre study observes hospitalised adult patients with confirmed SARS-CoV-2 infection, utilising a combination of retrospective and prospective data collection. It aims to gather clinical and laboratory variables from around 35,000 patients, with potential for a larger sample size. Data analysis will involve biostatistical and machine-learning techniques. Selected patients will provide biological material. The study started on October 14, 2021 and is scheduled to end on October 13, 2026. DISCUSSION: The analysis of a large sample of retrospective and prospective data about the acute phase of SARS CoV-2 infection in hospitalised patients, viral variants and vaccination in several European and non-European countries will help us to better understand risk factors for disease severity and the interplay between SARS CoV-2 variants, immune responses and vaccine efficacy. The main strengths of this study are the large sample size, the long study duration covering different waves of COVID-19 and the collection of biological samples that allows future research. TRIAL REGISTRATION: The trial has been registered on ClinicalTrials.gov. The unique identifier assigned to this trial is NCT05463380.


Subject(s)
COVID-19 , Vaccines , Adult , Aged , Humans , Cohort Studies , Multicenter Studies as Topic , Retrospective Studies , SARS-CoV-2 , Treatment Outcome
13.
BMC Infect Dis ; 23(1): 684, 2023 Oct 13.
Article in English | MEDLINE | ID: mdl-37833640

ABSTRACT

BACKGROUND: Post-COVID-19 condition refers to persistent or new onset symptoms occurring three months after acute COVID-19, which are unrelated to alternative diagnoses. Symptoms include fatigue, breathlessness, palpitations, pain, concentration difficulties ("brain fog"), sleep disorders, and anxiety/depression. The prevalence of post-COVID-19 condition ranges widely across studies, affecting 10-20% of patients and reaching 50-60% in certain cohorts, while the associated risk factors remain poorly understood. METHODS: This multicentre cohort study, both retrospective and prospective, aims to assess the incidence and risk factors of post-COVID-19 condition in a cohort of recovered patients. Secondary objectives include evaluating the association between circulating SARS-CoV-2 variants and the risk of post-COVID-19 condition, as well as assessing long-term residual organ damage (lung, heart, central nervous system, peripheral nervous system) in relation to patient characteristics and virology (variant and viral load during the acute phase). Participants will include hospitalised and outpatient COVID-19 patients diagnosed between 01/03/2020 and 01/02/2025 from 8 participating centres. A control group will consist of hospitalised patients with respiratory infections other than COVID-19 during the same period. Patients will be followed up at the post-COVID-19 clinic of each centre at 2-3, 6-9, and 12-15 months after clinical recovery. Routine blood exams will be conducted, and patients will complete questionnaires to assess persisting symptoms, fatigue, dyspnoea, quality of life, disability, anxiety and depression, and post-traumatic stress disorders. DISCUSSION: This study aims to understand post-COVID-19 syndrome's incidence and predictors by comparing pandemic waves, utilising retrospective and prospective data. Gender association, especially the potential higher prevalence in females, will be investigated. Symptom tracking via questionnaires and scales will monitor duration and evolution. Questionnaires will also collect data on vaccination, reinfections, and new health issues. Biological samples will enable future studies on post-COVID-19 sequelae mechanisms, including inflammation, immune dysregulation, and viral reservoirs. TRIAL REGISTRATION: This study has been registered with ClinicalTrials.gov under the identifier NCT05531773.


Subject(s)
COVID-19 , SARS-CoV-2 , Female , Humans , Cohort Studies , COVID-19/epidemiology , Fatigue/epidemiology , Fatigue/etiology , Post-Acute COVID-19 Syndrome , Prospective Studies , Quality of Life , Retrospective Studies , Male
14.
Bioinformatics ; 36(21): 5205-5213, 2021 01 29.
Article in English | MEDLINE | ID: mdl-32683440

ABSTRACT

MOTIVATION: The use of genome data for diagnosis and treatment is becoming increasingly common. Researchers need access to as many genomes as possible to interpret the patient genome, to obtain some statistical patterns and to reveal disease-gene relationships. The sensitive information contained in the genome data and the high risk of re-identification increase the privacy and security concerns associated with sharing such data. In this article, we present an approach to identify disease-associated variants and genes while ensuring patient privacy. The proposed method uses secure multi-party computation to find disease-causing mutations under specific inheritance models without sacrificing the privacy of individuals. It discloses only variants or genes obtained as a result of the analysis. Thus, the vast majority of patient data can be kept private. RESULTS: Our prototype implementation performs analyses on thousands of genomic data in milliseconds, and the runtime scales logarithmically with the number of patients. We present the first inheritance model (recessive, dominant and compound heterozygous) based privacy-preserving analyses of genomic data to find disease-causing mutations. Furthermore, we re-implement the privacy-preserving methods (MAX, SETDIFF and INTERSECTION) proposed in a previous study. Our MAX, SETDIFF and INTERSECTION implementations are 2.5, 1122 and 341 times faster than the corresponding operations of the state-of-the-art protocol, respectively. AVAILABILITY AND IMPLEMENTATION: https://gitlab.com/DIFUTURE/privacy-preserving-genomic-diagnosis. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Subject(s)
Genomics , Privacy , Confidentiality , Genome-Wide Association Study , Humans , Mutation
15.
Am J Hematol ; 97(10): 1309-1323, 2022 10.
Article in English | MEDLINE | ID: mdl-36071578

ABSTRACT

Allogeneic hematopoietic cell transplantation (HCT) effectively treats high-risk hematologic diseases but can entail HCT-specific complications, which may be minimized by appropriate patient management, supported by accurate, individual risk estimation. However, almost all HCT risk scores are limited to a single risk assessment before HCT without incorporation of additional data. We developed machine learning models that integrate both baseline patient data and time-dependent laboratory measurements to individually predict mortality and cytomegalovirus (CMV) reactivation after HCT at multiple time points per patient. These gradient boosting machine models provide well-calibrated, time-dependent risk predictions and achieved areas under the receiver-operating characteristic of 0.92 and 0.83 and areas under the precision-recall curve of 0.58 and 0.62 for prediction of mortality and CMV reactivation, respectively, in a 21-day time window. Both models were successfully validated in a prospective, non-interventional study and performed on par with expert hematologists in a pilot comparison.


Subject(s)
Cytomegalovirus Infections , Hematopoietic Stem Cell Transplantation , Cytomegalovirus , Cytomegalovirus Infections/etiology , Hematopoietic Stem Cell Transplantation/adverse effects , Humans , Machine Learning , Prospective Studies
16.
Nature ; 535(7613): 556-60, 2016 07 28.
Article in English | MEDLINE | ID: mdl-27338952

ABSTRACT

Interruption of combination antiretroviral therapy in HIV-1-infected individuals leads to rapid viral rebound. Here we report the results of a phase IIa open label clinical trial evaluating 3BNC117,a broad and potent neutralizing antibody against the CD4 binding site of the HIV-1 Env protein, during analytical treatment interruption in 13 HIV-1-infected individuals. Participants with 3BNC117-sensitive virus outgrowth cultures were enrolled. Results show that two or four 30 mg kg(-1) 3BNC117 infusions,separated by 3 or 2 weeks, respectively, are generally well tolerated.Infusions are associated with a delay in viral rebound of 5-9 weeks after two infusions, and up to 19 weeks after four infusions, or an average of 6.7 and 9.9 weeks, respectively, compared with 2.6 weeks for historical controls (P < 0.00001). Rebound viruses arise predominantly from a single provirus. In most individuals,emerging viruses show increased resistance, indicating escape.However, 30% of participants remained suppressed until antibody concentrations waned below 20 µg ml(-1), and the viruses emerging in all but one of these individuals showed no apparent resistance to 3BCN117, suggesting failure to escape over a period of 9-19 weeks.We conclude that the administration of 3BNC117 exerts strong selective pressure on HIV-1 emerging from latent reservoirs during analytical treatment interruption in humans.


Subject(s)
Anti-HIV Agents/administration & dosage , Antibodies, Neutralizing/immunology , HIV Antibodies/immunology , HIV Infections/drug therapy , HIV Infections/virology , HIV-1/growth & development , HIV-1/immunology , Adolescent , Adult , Aged , Anti-HIV Agents/pharmacology , Anti-HIV Agents/therapeutic use , Antibodies, Monoclonal, Humanized , Antibodies, Neutralizing/administration & dosage , Antibodies, Neutralizing/therapeutic use , Binding Sites/drug effects , Binding Sites/immunology , Broadly Neutralizing Antibodies , CD4 Antigens/metabolism , Disease Reservoirs/virology , Drug Administration Schedule , Female , HIV Antibodies/administration & dosage , HIV Antibodies/therapeutic use , HIV Envelope Protein gp160/antagonists & inhibitors , HIV Envelope Protein gp160/chemistry , HIV Envelope Protein gp160/immunology , HIV Envelope Protein gp160/metabolism , HIV Infections/immunology , HIV-1/drug effects , Historically Controlled Study , Humans , Male , Middle Aged , Proviruses/drug effects , Proviruses/growth & development , Proviruses/immunology , Time Factors , Tissue Distribution , Viral Load/drug effects , Viral Load/immunology , Young Adult
17.
BMC Public Health ; 22(1): 1167, 2022 06 11.
Article in English | MEDLINE | ID: mdl-35690802

ABSTRACT

BACKGROUND: Lower respiratory tract infections are among the main causes of death. Although there are many respiratory viruses, diagnostic efforts are focused mainly on influenza. The Respiratory Viruses Network (RespVir) collects infection data, primarily from German university hospitals, for a high diversity of infections by respiratory pathogens. In this study, we computationally analysed a subset of the RespVir database, covering 217,150 samples tested for 17 different viral pathogens in the time span from 2010 to 2019. METHODS: We calculated the prevalence of 17 respiratory viruses, analysed their seasonality patterns using information-theoretic measures and agglomerative clustering, and analysed their propensity for dual infection using a new metric dubbed average coinfection exclusion score (ACES). RESULTS: After initial data pre-processing, we retained 206,814 samples, corresponding to 1,408,657 performed tests. We found that Influenza viruses were reported for almost the half of all infections and that they exhibited the highest degree of seasonality. Coinfections of viruses are frequent; the most prevalent coinfection was rhinovirus/bocavirus and most of the virus pairs had a positive ACES indicating a tendency to exclude each other regarding infection. CONCLUSIONS: The analysis of respiratory viruses dynamics in monoinfection and coinfection contributes to the prevention, diagnostic, treatment, and development of new therapeutics. Data obtained from multiplex testing is fundamental for this analysis and should be prioritized over single pathogen testing.


Subject(s)
Coinfection , Respiratory Tract Infections , Virus Diseases , Viruses , Coinfection/epidemiology , Humans , Infant , Rhinovirus , Virus Diseases/epidemiology
18.
J Clin Microbiol ; 59(9): e0089621, 2021 08 18.
Article in English | MEDLINE | ID: mdl-34213977

ABSTRACT

The identification and isolation of highly infectious SARS-CoV-2-infected individuals is an important public health strategy. Rapid antigen detection tests (RADT) are promising tools for large-scale screenings due to timely results and feasibility for on-site testing. Nonetheless, the diagnostic performance of RADT in detecting infectious individuals is not yet fully determined. In this study, RT-qPCR and virus culture of RT-qPCR-positive samples were used to evaluate and compare the performance of the Standard Q COVID-19 Ag test in detecting SARS-CoV-2-infected and possibly infectious individuals. To this end, two combined oro- and nasopharyngeal swabs were collected at a routine SARS-CoV-2 diagnostic center. A total of 2,028 samples were tested, and 118 virus cultures were inoculated. SARS-CoV-2 infection was detected in 210 samples by RT-qPCR, representing a positive rate of 10.36%. The Standard Q COVID-19 Ag test yielded a positive result in 92 (4.54%) samples resulting in an overall sensitivity and specificity of 42.86 and 99.89%, respectively. For adjusted CT values of <20 (n = 14), <25 (n = 57), and <30 (n = 88), the RADT reached sensitivities of 100, 98.25, and 88.64%, respectively. All 29 culture-positive samples were detected by the RADT. Although the overall sensitivity was low, the Standard Q COVID-19 Ag test reliably detected patients with high RNA loads. In addition, negative RADT results fully corresponded with the lack of viral cultivability in Vero E6 cells. These results indicate that RADT can be a valuable tool for the detection of individuals with high RNA loads that are likely to transmit SARS-CoV-2.


Subject(s)
COVID-19 , Communicable Diseases , Humans , Real-Time Polymerase Chain Reaction , SARS-CoV-2 , Sensitivity and Specificity
19.
Nucleic Acids Res ; 47(W1): W605-W609, 2019 07 02.
Article in English | MEDLINE | ID: mdl-31114892

ABSTRACT

More and more affordable high-throughput techniques for measuring molecular features of biomedical samples have led to a huge increase in availability and size of different types of multi-omic datasets, containing, for example, genetic or histone modification data. Due to the multi-view characteristic of the data, established approaches for exploratory analysis are not directly applicable. Here we present web-rMKL, a web server that provides an integrative dimensionality reduction with subsequent clustering of samples based on data from multiple inputs. The underlying machine learning method rMKL-LPP performed best for clinical enrichment in a recent benchmark of state-of-the-art multi-view clustering algorithms. The method was introduced for a multi-omic cancer subtype discovery setting, however, it is not limited to this application scenario as exemplified by a presented use case for stem cell differentiation. web-rMKL offers an intuitive interface for uploading data and setting the parameters. rMKL-LPP runs on the back end and the user may receive notifications once the results are available. We also introduce a preprocessing tool for generating kernel matrices from tables containing numerical feature values. This program can be used to generate admissible input if no precomputed kernel matrices are available. The web server is freely available at web-rMKL.org.


Subject(s)
Machine Learning , Software , Cell Differentiation , Cluster Analysis , DNA Methylation , Gene Expression Profiling , Genomics , Humans , Internet , MicroRNAs/metabolism , Squamous Cell Carcinoma of Head and Neck/mortality , Stem Cells/cytology , Survival Analysis
20.
Nucleic Acids Res ; 47(20): 10580-10596, 2019 11 18.
Article in English | MEDLINE | ID: mdl-31584093

ABSTRACT

Chromatin accessibility maps are important for the functional interpretation of the genome. Here, we systematically analysed assay specific differences between DNase I-seq, ATAC-seq and NOMe-seq in a side by side experimental and bioinformatic setup. We observe that most prominent nucleosome depleted regions (NDRs, e.g. in promoters) are roboustly called by all three or at least two assays. However, we also find a high proportion of assay specific NDRs that are often 'called' by only one of the assays. We show evidence that these assay specific NDRs are indeed genuine open chromatin sites and contribute important information for accurate gene expression prediction. While technically ATAC-seq and DNase I-seq provide a superb high NDR calling rate for relatively low sequencing costs in comparison to NOMe-seq, NOMe-seq singles out for its genome-wide coverage allowing to not only detect NDRs but also endogenous DNA methylation and as we show here genome wide segmentation into heterochromatic B domains and local phasing of nucleosomes outside of NDRs. In summary, our comparisons strongly suggest to consider assay specific differences for the experimental design and for generalized and comparative functional interpretations.


Subject(s)
Chromatin Immunoprecipitation Sequencing/methods , Chromatin Immunoprecipitation Sequencing/standards , Hep G2 Cells , Humans , Nucleosomes/chemistry , Nucleosomes/metabolism , Promoter Regions, Genetic
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