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Laboratory of Experimental Virology Virus Discovery 454 sequencing Michel de Vries micheldevries@high-throughput-sequencing.com
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Laboratory of Experimental Virology Introduction In 5-40 % of hospitalized patients with suspected respiratory viral infection no agent is identified. Possible problem: New or variant. Virus Discovery cDNA-AFLP (VIDISCA) was developed in 2004. * VIDISCA can amplify both RNA and DNA viruses without prior knowledge of the target sequence. Based on restriction enzyme cleavage sites + ligation of adaptors + PCR. * van der Hoek et al, Nature medicine 2004
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Laboratory of Experimental Virology Problems VIDISCA amplifies background ribosomal RNA (rRNA) and chromosomal DNA together with viral sequences. This background amplification interferes with VIDISCA by acting as competitors. Clinical samples such as nose washing are full with background rRNA and chromosomal DNA. Solution If a high number of fragments are randomly sequenced, a minority population can be identified.
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Laboratory of Experimental Virology High throughput sequencing High throughput sequencing makes it possible to sequence a large amount of DNA fragments in a single run. One of these machines is the 454 FLX sequencer of Roche. The method binds a single DNA fragment to a bead which is clonally amplified. Per run a maximum of 1.5 million beads can be used resulting in about 400.000 quality sequences. Multiplex identifiers (MID) are 10 nucleotides long barcodes that are recognized by our software. The MID can be incorporated into samples allowing multiple samples to be pooled. By using MIDs more samples can be processed in a single run
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Laboratory of Experimental Virology VIDISCA Cloning in TA vector Colony-PCR Sequencing of colony-PCR products Selective PCR (16 primer combin.)
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Laboratory of Experimental Virology VIDISCA-454 Cloning in TA vector Colony-PCR Sequencing of colony-PCR products Selective PCR (16 primer combin.) fragmentSize (nu) 1120-200 2200-300 3300-400 - Fragment separation and isolation 454 sequencing
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Laboratory of Experimental Virology Virus culture supernatant in VIDSICA-454 12 times coxsackievirus B4 supernatant (2.0 E8 copies/ml) as input. Each with a specific MID-primer A anchor. Sequences per MID were separated, aligned and compared to GenBank database.
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Laboratory of Experimental Virology Result MIDNr. of sequencesViral sequences% of total 12805247788.3 23890328284.4 32369200784.7 42782253491.1 53056254083.1 62271200088.1 71429135494.8 83830296177.3 93018282193.5 103040284093.4 115216499195.7 122891274094.8 Total365973254788.9
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Laboratory of Experimental Virology Clinical samples in VIDSICA-454 12 clinical samples (nose washings). Again each sample with a specific MID-primer A anchor Virus in the samples were previously identified via multiplex PCR but given double blind. Samples containing high/medium/low viral load of known viruses.
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Laboratory of Experimental Virology Result 3 12 clinical samples tested with VIDISCA and VIDSICA-454 VIDISCAVIDISCA-454 Samples tested 12 Nr. of virus indentified 16 Viruses identified HCoV 229E HCoV OC43 RSV (2X) Rhinovirus hMPV
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Laboratory of Experimental Virology Sample IDVIDISCA VIDISCA-454 (% of sequences) result by multiplex (viral copies/100 μl) 20752434NegativeNegative (<0.014 %) RSV (1.1 E6) 20752437HCoV 229E (1.1 %) HCoV 229E (4.3 E5) 20752240Negative hMPV (0.006 %) hMPV (7.6 E6) 20750951Negative HCoV OC43 (0.006%) HCoV OC43 (5.8 E4) 20751197Negative (< 0.007) HRV (2.3 E11) 20751967Negative RSV (0.33 %) RSV (3.4 E8) 20752218Negative (<0.04 %) hMPV (5.4 E4) 20752090Negative (<0.05%) HRV (8.3 E5) 20751802Negative HRV-C (0.017 %) HRV (5.6 E11) 20752358Negative (<0.012%) hMPV (2.3 E9) 20752481Negative (<0.021 %) RSV (3.3 E5) 20752346NegativeRSV (0.166 %) RSV (8.3 E7) Result 4
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Laboratory of Experimental Virology Conclusion VIDISCA can be combined using high throughput sequencing. Twelve MIDs can be included allowing 12 samples to be pooled. By pooling samples we can sequence at least 48 samples in a single run. High throughput sequencing result higher viral genome nucleotides sequenced. VIDISCA-454 can identify viral fragments from direct patient material.
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Laboratory of Experimental Virology Advantage High throughput sequencing Cost per sample are reduced by 50 %. More samples per time unit. More sequence information per sample. More sensitive.
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Laboratory of Experimental Virology Acknowledgements Laboratory of Experimental Virology Nuno Faria Martin Deijs Maarten F. Jebbink Lia van der Hoek Dipartimento di Sanità Pubblica-Microbiologia-Virologia, Università degli Studi di Milano Marta Canuti Department of Neurogenetics Marja Jakobs Frank Baas Laboratory of Clinical Virology Richard Molenkamp Department of Clinical Epidemiology, Biostatistics and Bioinformatics Barbera van Schaik Angela Luijf micheldevries@high-throughput-sequencing.com
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