Evaluation of targeted next-generation sequencing for detection of equine pathogens in clinical samples

Equine infectious disease outbreaks may have profound economic impact, resulting in losses of millions of dollars of revenue as a result of horse loss, quarantine, and cancelled events. Early and accurate diagnosis is essential to limit the spread of infectious diseases. However, laboratory detection of infectious agents, especially the simultaneous detection of multiple agents, can be challenging to the clinician and diagnostic laboratory. Next-generation sequencing (NGS), which allows millions of DNA templates to be sequenced simultaneously in a single reaction, is an ideal technology for comprehensive testing. We conducted a proof-of-concept study of targeted NGS to detect 62 common equine bacterial, viral, and parasitic pathogens in clinical samples. We designed 264 primers and constructed a bioinformatics tool for the detection of targeted pathogens. The designed primers were able to specifically detect the intended pathogens. Results of testing 27 clinical samples with our targeted NGS assay compared with results of routine tests (assessed as a group) yielded positive percent agreement of 81% and negative percent agreement of 83%, overall agreement of 81%, and kappa of 0.56 (moderate agreement). This moderate agreement was likely the result of low sensitivity of some primers. However, our NGS assay successfully detected multiple pathogens in the clinical samples, including some pathogens missed by routine techniques.

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Evaluation of Targeted Next-Generation Sequencing for Detection of Bovine Pathogens in Clinical Samples

Journal of Clinical Microbiology ◽

10.1128/jcm.00399-18 ◽

2018 ◽

Vol 56 (7) ◽

Cited By ~ 13

Author(s):

Eman Anis ◽

Ian K. Hawkins ◽

Marcia R. S. Ilha ◽

Moges W. Woldemeskel ◽

Jeremiah T. Saliki ◽

...

Keyword(s):

Next Generation Sequencing ◽

Cost Effective ◽

Laboratory Diagnosis ◽

Diagnostic Techniques ◽

Clinical Samples ◽

Next Generation ◽

Diagnostic Laboratory ◽

Effective Manner ◽

Parasitic Pathogens ◽

Generation Sequencing

ABSTRACTThe laboratory diagnosis of infectious diseases, especially those caused by mixed infections, is challenging. Routinely, it requires submission of multiple samples to separate laboratories. Advances in next-generation sequencing (NGS) have provided the opportunity for development of a comprehensive method to identify infectious agents. This study describes the use of target-specific primers for PCR-mediated amplification with the NGS technology in which pathogen genomic regions of interest are enriched and selectively sequenced from clinical samples. In the study, 198 primers were designed to target 43 common bovine and small-ruminant bacterial, fungal, viral, and parasitic pathogens, and a bioinformatics tool was specifically constructed for the detection of targeted pathogens. The primers were confirmed to detect the intended pathogens by testing reference strains and isolates. The method was then validated using 60 clinical samples (including tissues, feces, and milk) that were also tested with other routine diagnostic techniques. The detection limits of the targeted NGS method were evaluated using 10 representative pathogens that were also tested by quantitative PCR (qPCR), and the NGS method was able to detect the organisms from samples with qPCR threshold cycle (CT) values in the 30s. The method was successful for the detection of multiple pathogens in the clinical samples, including some additional pathogens missed by the routine techniques because the specific tests needed for the particular organisms were not performed. The results demonstrate the feasibility of the approach and indicate that it is possible to incorporate NGS as a diagnostic tool in a cost-effective manner into a veterinary diagnostic laboratory.

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Multiplex Picoliter-Droplet Digital PCR for Quantitative Assessment of DNA Integrity in Clinical Samples

Clinical Chemistry ◽

10.1373/clinchem.2012.193409 ◽

2013 ◽

Vol 59 (5) ◽

pp. 815-823 ◽

Cited By ~ 71

Author(s):

Audrey Didelot ◽

Steve K Kotsopoulos ◽

Audrey Lupo ◽

Deniz Pekin ◽

Xinyu Li ◽

...

Keyword(s):

Next Generation Sequencing ◽

Simultaneous Detection ◽

Digital Pcr ◽

Clinical Samples ◽

Dna Integrity ◽

Next Generation ◽

Sequencing Data ◽

Integrity Test ◽

Picoliter Droplet ◽

Generation Sequencing

BACKGROUND Assessment of DNA integrity and quantity remains a bottleneck for high-throughput molecular genotyping technologies, including next-generation sequencing. In particular, DNA extracted from paraffin-embedded tissues, a major potential source of tumor DNA, varies widely in quality, leading to unpredictable sequencing data. We describe a picoliter droplet–based digital PCR method that enables simultaneous detection of DNA integrity and the quantity of amplifiable DNA. METHODS Using a multiplex assay, we detected 4 different target lengths (78, 159, 197, and 550 bp). Assays were validated with human genomic DNA fragmented to sizes of 170 bp to 3000 bp. The technique was validated with DNA quantities as low as 1 ng. We evaluated 12 DNA samples extracted from paraffin-embedded lung adenocarcinoma tissues. RESULTS One sample contained no amplifiable DNA. The fractions of amplifiable DNA for the 11 other samples were between 0.05% and 10.1% for 78-bp fragments and ≤1% for longer fragments. Four samples were chosen for enrichment and next-generation sequencing. The quality of the sequencing data was in agreement with the results of the DNA-integrity test. Specifically, DNA with low integrity yielded sequencing results with lower levels of coverage and uniformity and had higher levels of false-positive variants. CONCLUSIONS The development of DNA-quality assays will enable researchers to downselect samples or process more DNA to achieve reliable genome sequencing with the highest possible efficiency of cost and effort, as well as minimize the waste of precious samples.

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Using sequential next-generation sequencing assays to identify germline cancer predisposition variants.

Journal of Clinical Oncology ◽

10.1200/jco.2020.38.15_suppl.1581 ◽

2020 ◽

Vol 38 (15_suppl) ◽

pp. 1581-1581 ◽

Cited By ~ 1

Author(s):

Ira Lignugaris Kraft ◽

Amy M. Trottier ◽

George F. Steinhardt ◽

Nifang Niu ◽

Pankhuri Wanjari ◽

...

Keyword(s):

Next Generation Sequencing ◽

Clinical Care ◽

Clinical Samples ◽

Clinical Test ◽

Next Generation ◽

Worst Case ◽

Germline Variants ◽

Targeted Ngs ◽

Generation Sequencing ◽

Over Time

1581 Background: Next-generation sequencing (NGS) increasingly guides clinical care in hematological malignancies by identifying DNA mutations that change dynamically over time. Clinical samples contain variable numbers of malignant and non-malignant cells. So, careful interpretation is required to determine if a particular variant is somatic, germline, or clonal hematopoietic in origin. Methods: The University of Chicago uses a targeted NGS assay of ~1200 genes, reporting 150 as a clinical test. We aimed to identify individuals with hereditary predisposition by detecting persistent variants on sequential assays regardless of disease state. Results: 943 NGS assays from July 2017 – Feb. 2020 on 711 patients [ages 1 mo – 95 yrs, median 65 yrs] were included. 2,320 variants in 33 genes were identified with 144 patients having the same variant identified on more than one assay. Single nucleotide variants (SNVs) with variant allele frequency (VAF) ≥ 0.3 were prioritized. The first candidate gene identified with potential germline SNVs was CSF3R. 28 unique SNVs in CSF3R were found, 14 were confirmed as germline, 6 somatic, and 8 were unconfirmed due to lack of available tissue. At least 2 confirmed germline CSF3R variants were likely deleterious based on functional testing. Sequential SNVs were quantified using the coefficient of variation, characterizing each by change in VAF over time. Using a worst-case-scenario analysis, in which unconfirmed variants were not counted as germline, a computer algorithm was designed to identify potential germline variants (specificity 0.89, PPV 0.75). Via an iterative method, the algorithm compares new assays to a pool of previously reported tests, flagging patients with potential germline mutations so that biopsies may be studied in the lab, records reviewed, and referrals placed to genetic counselors. To date, 61 patients with 89 likely germline variants have been identified. Known hereditary hematological malignancy genes, such as ATM, ASXL1, CHEK2, DDX41, TSC1, and RUNX1, had the most variants identified. Limitations include the challenge in distinguishing variants that do not change over time, reliance on a targeted NGS panel, and normalizing VAF data prior to analysis. Conclusions: These data highlight the utility of NGS of bone marrow and peripheral blood samples to identify patients suspected of having germline DNA variants. In addition to identifying known predisposition syndromes, one may discover new inherited cancer syndromes and help guide clinical practice in real time.

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Detection and Typing of Human Enteroviruses from Clinical Samples by Entire-Capsid Next Generation Sequencing

Viruses ◽

10.3390/v13040641 ◽

2021 ◽

Vol 13 (4) ◽

pp. 641

Author(s):

Manasi Majumdar ◽

Cristina Celma ◽

Elaine Pegg ◽

Krunal Polra ◽

Jake Dunning ◽

...

Keyword(s):

Next Generation Sequencing ◽

Sensitivity And Specificity ◽

Severe Disease ◽

Clinical Samples ◽

Whole Genome ◽

Next Generation ◽

Coding Region ◽

Diagnostic Laboratory ◽

Next Generation Sequencing Ngs ◽

Generation Sequencing

There are increasing concerns of infections by enteroviruses (EVs) causing severe disease in humans. EV diagnostic laboratory methods show differences in sensitivity and specificity as well as the level of genetic information provided. We examined a detection method for EVs based on next generation sequencing (NGS) analysis of amplicons covering the entire capsid coding region directly synthesized from clinical samples. One hundred and twelve clinical samples from England; previously shown to be positive for EVs, were analyzed. There was high concordance between the results obtained by the new NGS approach and those from the conventional Sanger method used originally with agreement in the serotypes identified in the 83 samples that were typed by both methods. The sensitivity and specificity of the NGS method compared to those of the conventional Sanger sequencing typing assay were 94.74% (95% confidence interval, 73.97% to 99.87%) and 97.85% (92.45% to 99.74%) for Enterovirus A, 93.75% (82.80% to 98.69%) and 89.06% (78.75% to 95.49%) for Enterovirus B, 100% (59.04% to 100%) and 98.10% (93.29% to 99.77%) for Enterovirus C, and 100% (75.29% to 100%) and 100% (96.34% to 100%) for Enterovirus D. The NGS method identified five EVs in previously untyped samples as well as additional viruses in some samples, indicating co-infection. This method can be easily expanded to generate whole-genome EV sequences as we show here for EV-D68. Information from capsid and whole-genome sequences is critical to help identifying the genetic basis for changes in viral properties and establishing accurate spatial-temporal associations between EV strains of public health relevance.

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Implementation of next-generation sequencing for virus identification in veterinary diagnostic laboratories

Journal of Veterinary Diagnostic Investigation ◽

10.1177/1040638720982630 ◽

2020 ◽

pp. 104063872098263

Author(s):

Jakub Kubacki ◽

Cornel Fraefel ◽

Claudia Bachofen

Keyword(s):

Next Generation Sequencing ◽

Influenza A ◽

Swine Influenza ◽

Viral Metagenomics ◽

Clinical Samples ◽

Next Generation ◽

Diagnostic Laboratory ◽

Virus Identification ◽

Field Samples ◽

Generation Sequencing

The value of next-generation sequencing (NGS)-based applications for testing purposes in human medicine is widely recognized. Although NGS-based metagenomic screening may be of interest in veterinary medicine, in particular for intensively farmed livestock species such as pigs, there is a lack of protocols tailored to veterinary requirements, likely because of the high diversity of species and samples. Therefore, we developed an NGS-based protocol for use in veterinary virology and present here different applications in porcine medicine. To develop the protocol, each step of sample preparation was optimized using porcine samples spiked with various RNA and DNA viruses. The resulting protocol was tested with clinical samples previously confirmed to be positive for specific viruses by a diagnostic laboratory. Additionally, we validated the protocol in an NGS viral metagenomics ring trial and tested the protocol on viral multiplex reference material (NIBSC, U.K.). We applied our ViroScreen protocol successfully for 1) virus identification, 2) virus characterization, and 3) herd screening. We identified torque teno sus virus and atypical porcine pestivirus in a neurologic case, determined the full-length genome sequence of swine influenza A virus in field samples, and screened pigs using pen floor fecal samples and chewing rope liquid.

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Investigation of neglected protists Blastocystis sp. and Dientamoeba fragilis in immunocompetent and immunodeficient diarrheal patients using both conventional and molecular methods

PLoS Neglected Tropical Diseases ◽

10.1371/journal.pntd.0009779 ◽

2021 ◽

Vol 15 (10) ◽

pp. e0009779

Author(s):

Fakhriddin Sarzhanov ◽

Funda Dogruman-Al ◽

Monica Santin ◽

Jenny G. Maloney ◽

Ayse Semra Gureser ◽

...

Keyword(s):

Next Generation Sequencing ◽

Gastrointestinal Symptoms ◽

Molecular Methods ◽

Clinical Samples ◽

Rrna Gene ◽

Next Generation ◽

Dientamoeba Fragilis ◽

Significant Difference ◽

Generation Sequencing ◽

Immunocompetent Patients

Introduction The clinical significance of Blastocystis sp. and Dientamoeba fragilis in patients with gastrointestinal symptoms is a controversial issue. Since the pathogenicity of these protists has not been fully elucidated, testing for these organisms is not routinely pursued by most laboratories and clinicians. Thus, the prevalence of these organisms and the subtypes of Blastocystis sp. in human patients in Turkey are not well characterized. This study aimed to determine the prevalence of Blastocystis sp. and D. fragilis in the diarrheic stool samples of immunodeficient and immunocompetent patients using conventional and molecular methods and to identify Blastocystis sp. subtypes using next generation sequencing. Material and methods Individual stool specimens were collected from 245 immunodeficient and 193 immunocompetent diarrheic patients between March 2017 and December 2019 at the Gazi University Training and Research Hospital in Ankara, Turkey. Samples were screened for Blastocystis sp. and D. fragilis by conventional and molecular methods. Molecular detection of both protists was achieved by separate qPCRs targeting a partial fragment of the SSU rRNA gene. Next generation sequencing was used to identify Blastocystis sp. subtypes. Results The prevalence of Blastocystis sp. and D. fragilis was 16.7% and 11.9%, respectively as measured by qPCR. The prevalence of Blastocystis sp. and D. fragilis was lower in immunodeficient patients (12.7% and 10.6%, respectively) compared to immunocompetent patients (21.8% and 13.5%, respectively). Five Blastocystis sp. subtypes were identified and the following subtype distribution was observed: ST3 54.4% (n = 37), ST2 16.2% (n = 11), ST1 4.4% (n = 3), ST6 2.9% (n = 2), ST4 1.5% (n = 1), ST2/ST3 11.8% (n = 8) and ST1/ST3 8.8% (n = 6). There was no statistically significant difference in the distribution of Blastocystis sp. subtypes between immunocompetent and immunodeficient patients. Conclusion and recommendation Our findings demonstrated that Blastocystis sp. and D. fragilis are commonly present in immunocompetent and immunodeficient patients with diarrhea. This study is the first to use next generation sequencing to address the presence of Blastocystis sp. mixed subtypes and intra-subtype variability in clinical samples in Turkey.

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Targeted Next-Generation Sequencing of Cancer-Related Genes in a Norwegian Patient Cohort With Head and Neck Squamous Cell Carcinoma Reveals Novel Actionable Mutations and Correlations With Pathological Parameters

Frontiers in Oncology ◽

10.3389/fonc.2021.734134 ◽

2021 ◽

Vol 11 ◽

Author(s):

Harsh N. Dongre ◽

Hilde Haave ◽

Siren Fromreide ◽

Fredrik A. Erland ◽

Svein Erik Emblem Moe ◽

...

Keyword(s):

Next Generation Sequencing ◽

Head And Neck ◽

Squamous Cell ◽

Ffpe Tissue ◽

Next Generation ◽

Targeted Next Generation Sequencing ◽

Mutational Burden ◽

Custom Made ◽

Targeted Ngs ◽

Generation Sequencing

BackgroundTargeted next-generation sequencing (NGS) is increasingly applied in clinical oncology to advance personalized treatment. Despite success in many other tumour types, use of targeted NGS panels for assisting diagnosis and treatment of head and neck squamous cell carcinomas (HNSCC) is still limited.AimThe focus of this study was to establish a robust NGS panel targeting most frequent cancer mutations in long-term preserved formalin-fixed paraffin-embedded (FFPE) tissue samples of HNSCC from routine diagnostics.Materials and MethodsTumour DNA obtained from archival FFPE tissue blocks of HNSCC patients treated at Haukeland University Hospital between 2003-2016 (n=111) was subjected to mutational analysis using a custom made AmpliSeq Library PLUS panel targeting 31 genes (Illumina). Associations between mutational burden and clinical and pathological parameters were investigated. Mutation and corresponding clinicopathological data from HNSCC were extracted for selected genes from the Cancer Genome Atlas (TCGA) and used for Chi-square and Kaplan-Meier analysis.ResultsThe threshold for sufficient number of reads was attained in 104 (93.7%) cases. Although the specific number of PCR amplified reads detected decreased, the number of NGS-annotated mutations did not significantly change with increased tissue preservation time. In HPV-negative carcinomas, mutations were detected mainly in TP53 (73.3%), FAT1 (26.7%) and FLG (16.7%) whereas in HPV-positive, the common mutations were in FLG (24.3%) FAT1 (17%) and FGFR3 (14.6%) genes. Other less common pathogenic mutations, including well reported SNPs were reproducibly identified. Presence of at least one cancer-specific mutations was found to be positively associated with an extensive desmoplastic stroma (p=0.019), and an aggressive type of invasive front (p=0.035), and negatively associated with the degree of differentiation (p=0.041). Analysis of TCGA data corroborated the association between cancer-specific mutations and tumour differentiation and survival analysis showed that tumours with at least one mutation had shorter disease-free and overall survival (p=0.005).ConclusionsA custom made targeted NGS panel could reliably detect several specific mutations in archival samples of HNSCCs preserved up to 17 years. Using this method novel associations between mutational burden and clinical and pathological parameters were detected and actionable mutations in HPV-positive HNSCC were discovered.

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Microsatellite instability detection using a large next-generation sequencing cancer panel across diverse tumour types

Journal of Clinical Pathology ◽

10.1136/jclinpath-2019-206136 ◽

2019 ◽

Vol 73 (2) ◽

pp. 83-89 ◽

Cited By ~ 6

Author(s):

Jiuhong Pang ◽

Tatyana Gindin ◽

Mahesh Mansukhani ◽

Helen Fernandes ◽

Susan Hsiao

Keyword(s):

Next Generation Sequencing ◽

Microsatellite Instability ◽

Microsatellite Loci ◽

Clinical Samples ◽

Next Generation ◽

Diverse Range ◽

Tree Classifier ◽

Generation Sequencing ◽

Cancer Panel ◽

Clinical Cases

AimMicrosatellite instability (MSI), a hallmark of DNA mismatch repair deficiency, is a key molecular biomarker with multiple clinical implications including the selection of patients for immunotherapy, identifying patients who may have Lynch syndrome and predicting prognosis in patients with colorectal tumours. Next-generation sequencing (NGS) provides the opportunity to interrogate large numbers of microsatellite loci concurrently with genomic variants. We sought to develop a method to detect MSI that would not require paired normal tissue and would leverage the sequence data obtained from a broad range of tumours tested using our 467-gene NGS Columbia Combined Cancer Panel (CCCP).MethodsAltered mononucleotide and dinucleotide microsatellite loci across the CCCP region of interest were evaluated in clinical samples encompassing a diverse range of tumour types. The number of altered loci was used to develop a decision tree classifier model trained on the retrospectively collected cohort of 107 clinical cases sequenced by the CCCP assay.ResultsThe classifier was able to correctly classify all cases and was then used to analyse a test set of clinical cases (n=112) and was able to correctly predict their MSI status with 100% sensitivity and specificity. Analysis of recurrently altered loci identified alterations in genes involved in DNA repair, signalling and transcriptional regulation pathways, many of which have been implicated in MSI tumours.ConclusionThis study highlights the utility of this approach, which should be applicable to laboratories performing similar testing.

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Next-generation sequencing for tumor mutation quantification using liquid biopsies

Clinical Chemistry and Laboratory Medicine (CCLM) ◽

10.1515/cclm-2019-0745 ◽

2020 ◽

Vol 58 (2) ◽

pp. 306-313 ◽

Cited By ~ 1

Author(s):

Mariano Provencio ◽

Clara Pérez-Barrios ◽

Miguel Barquin ◽

Virginia Calvo ◽

Fabio Franco ◽

...

Keyword(s):

Lung Cancer ◽

Next Generation Sequencing ◽

Correlation Coefficient ◽

Resistance Mutation ◽

Response To Treatment ◽

Clinical Samples ◽

Next Generation ◽

Liquid Biopsies ◽

Nsclc Patients ◽

Generation Sequencing

AbstractBackgroundNon-small cell lung cancer (NSCLC) patients benefit from targeted therapies both in first- and second-line treatment. Nevertheless, molecular profiling of lung cancer tumors after first disease progression is seldom performed. The analysis of circulating tumor DNA (ctDNA) enables not only non-invasive biomarker testing but also monitoring tumor response to treatment. Digital PCR (dPCR), although a robust approach, only enables the analysis of a limited number of mutations. Next-generation sequencing (NGS), on the other hand, enables the analysis of significantly greater numbers of mutations.MethodsA total of 54 circulating free DNA (cfDNA) samples from 52 NSCLC patients and two healthy donors were analyzed by NGS using the Oncomine™ Lung cfDNA Assay kit and dPCR.ResultsLin’s concordance correlation coefficient and Pearson’s correlation coefficient between mutant allele frequencies (MAFs) assessed by NGS and dPCR revealed a positive and linear relationship between the two data sets (ρc = 0.986; 95% confidence interval [CI] = 0.975–0.991; r = 0.987; p < 0.0001, respectively), indicating an excellent concordance between both measurements. Similarly, the agreement between NGS and dPCR for the detection of the resistance mutation p.T790M was almost perfect (K = 0.81; 95% CI = 0.62–0.99), with an excellent correlation in terms of MAFs (ρc = 0.991; 95% CI = 0.981–0.992 and Pearson’s r = 0.998; p < 0.0001). Importantly, cfDNA sequencing was successful using as low as 10 ng cfDNA input.ConclusionsMAFs assessed by NGS were highly correlated with MAFs assessed by dPCR, demonstrating that NGS is a robust technique for ctDNA quantification using clinical samples, thereby allowing for dynamic genomic surveillance in the era of precision medicine.

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