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Wednesday, June 27
8:30 Chairperson’s Remarks
8:40 Tech Talk Problem Solving Roundtables
Table #1: Hand-held Gene Analyzers: Desirable Characteristics and Target
Users
Moderator: Syed Hashsham, Michigan State University
Table #2: Amplification-based Diagnostics; Meeting the Challenges for Point of Care Medical
Devices
Moderator: Paul Cizdziel, RIKEN Yokohama Institute
Table #3: Gene Expression: Beyond Total RNA
Moderator: Jinshui Fan, Johns Hopkins Bayview Medical Center Genomics
Core
As we know, with techniques such as Microarrays, Real-time PCR, Northern blot, the majority of gene expression studies use Total RNA as the starting material. For my topic, I plan to pose discussions regarding the following Beyond Total RNA
issues:
- Detection of nascent/on-going transcribing RNA;
- Evaluation of RNA stability;
- Detect the targets of RNA regulating proteins;
- Transcription factor regulated transcription (ChIP,
ChIP-chip);
- Evaluation of on-going translation using gene arrays (polysomal fraction
arrays);
- microRNA detection;
- Detection of anti-sense RNA transcription, steady-state level, stability, and so
on.
Table #4: New Probes for Specific Nucleic Acid
Recognition
Moderator: Dmitry Kolpashchikov, Columbia University School of
Medicine
- Nanostructured probes and DNA nanostructures for nucleic acid
analysis
- Nucleic acid enzymes for detection of specific nucleotide
sequences
Table #5: Detection of Pathogens Using Nucleic
Acid-Based Technologies:
How willing are you to take action in your field with the
results?
Moderator: Alain Houde, Agriculture and Agri-Food Canada
Table #6: Critical Factors in Nucleic Acid Sample
Preparation for Miniaturized Analytical Systems
Moderator: N. J. Parham, Équipe diagnostique moléculaire / Molecular diagnostics team, Centre de recherche en infectiologie / Infectious disease research
center
As discussed in the pre-conference workshop “Sample Preparation and Handling for Nucleic Acid-Based Technologies”, there is a need for new, rapid, simple and automatable nucleic acid preparation methods. These methods must be able to purify a target from PCR inhibitors and concentrate scarce targets from complex samples often containing high concentrations of background DNA. Moreover, these methods must be automatable and miniaturizable to allow development of portable testing devices. This poses a major technical problem: How can we process large samples (often tens of milliliters) for target detection in miniaturized devices (e.g. microfluidic systems using nanoliter or picoliter volumes)? Material, manufacturing and methodological questions are
invited.
Table #7: Functionalized Microchips for the Direct Detection of
mRNA
Moderator: Sarah Margaret Spencer, Georgia State
University
- Detection of Bacterial pathogens
- Rapid detection in one-pot
- Specificity- working towards single base-pair discrimination
- Background Reduction- elimination of background interference with polymer coated surfaces
Table #8: Rapid Detection of Nucleic Acid Signatures from
Pathogen
Moderator: Susan W. Jones, Ph.D., MFS, Collection Scientist, Bacteriology, American Type Culture Collection, Biodefense and Emerging Infections Research Resource Repository
10:00 Networking Refreshment Break, Poster and Exhibit
Viewing

10:30 Rapid SNP Diagnostics Using Asymmetric Isothermal
Amplification and a Novel Mismatch Suppression Technology
Paul Cizdziel Ph.D., Senior Scientist, Genome Exploration
Research Group, RIKEN Yokohama Institute
We have developed a sensitive, accurate,
rapid, and simple DNA amplification scheme that shows
potential for translational medicine from pharmacogenomics-based
drug discovery thru to point-of-care diagnostics. Called the
SMart Amplification Process (SMAP), the method employs a new
DNA polymerase, unique primer design and background
suppression technology that can amplify target sequences
from crude cell lysates without thermocycling. The
specificity of the SMAP assay enables detection of
single-nucleotide differences such as somatic mutations in
tumors, and SNP variants. Because mismatch amplification can
be completely suppressed in SMAP, a reliable diagnostic
result can be achieved based exclusively on amplification
alone. We have developed optimized primer sets for
genotyping cytochrome P450 subtypes and variants and several
other SNP loci suspected of being clinically important for
drug metabolism or disease progression and/or treatment.
Furthermore, the ability to identify sequence variants in a
mixed population of mutant and genotypically normal cells
(such as a tumor biopsy), down to 0.1% abundance is a
significant advantage of SMAP over currently employed PCR-based
sequencing diagnostics for mutation detection. From sample
preparation to detection, amplification and hence diagnostic
determination can be achieved in as little as 30 minutes
from raw blood. SMAP is a new tool available to the research
and medical community; it achieves a highly desirable
single-step process goal for molecular diagnostics where
"amplification equals detection". This new
isothermal amplification technology introduces a novel
mismatch suppression approach that may be applicable to
other DNA amplification schemes. The specificity of
amplification by this technique is perhaps unrivaled
(mismatch amplification can be totally suppressed) by any
other technology. These features are being exploited for
rapid and inexpensive SNP and mutation detection from whole
blood and clinical tissue extracts (without DNA
purification). The technology will be published in Nature
Methods on February 6th (online) and the March print issue.
11:00 Use of Ethidium Bromide Monoazide (EMA) for
Quantification of Viable and Dead Bacteria from Fish
Fillets by PCR and Real-Time PCR
Jung-Iim Lee, Ph.D., Post Doctoral Fellow, Food Science,
University of Massachusetts - Amherst
Detection of viable microorganisms is
crucial in food safety and economy. There is a need for a
rapid and reliable method for detecting bacteria following
refrigerated storage and before sale, in order to prevent
the distribution of poor quality fish products to consumers.
Ethidium bromide monoazide (EMA) was utilized to selectively
allow PCR amplification of target DNA from viable cells
derived from a suspension of mixed bacterial flora derived
from cod fillets. Viable and dead differentiation is
obtained by covalent binding of EMA to DNA in dead cells by
photo-activation. EMA penetrates only dead cells with
compromised membrane/cell wall systems. DNA covalently bound
to EMA cannot be PCR amplified. Therefore, only DNA from
viable cells can be detected. Real-time PCR and conventional
PCR assays, using universal primers based on conserved 16S
rRNA sequences and EMA, were applied to the quantification
of viable bacteria derived from fish tissue. The purpose of
this study was to develop a quantitative PCR assay for
determining the total number of viable bacteria on fish
fillets following refrigerated and frozen storage. The
EMA-PCR assay offers a rapid method for quantitative
discrimination between viable and dead bacteria within hours
and could have a wide application in the life science field.
11:30 Engineering Polymerases for the Synthesis of
Ultrabright Fluorescent Probes
David Loakes, Ph.D., Senior Research Associate, Molecular Biology, MRC Lab Of Molecular Biology
DNA not only transmits genetic
information but is also a versatile supramolecular scaffold.
Although de novo chemical synthesis permits great
flexibility on the nature of chemical groups arranged and
displayed on DNA, it remains limited to short (<0.1kb)
polymers. We describe the engineering of a polymerase for
the synthesis of large double stranded DNA fragments
(>1kb) completely substituted in one base (dC or dA) by a
fluorescent dye-labeled equivalent such as Cy3- or Cy5-dCTP
or FITC-dATP. The resulting "CyDNA" displays
hundreds of fluorophores and is brightly colored and highly
fluorescent as well as resistant to cleavage by
endonucleases. Its bright fluorescence enables direct
imaging of FISH probes and single molecules in motion within
a capillary flowcell. CyDNA is the first of a new generation
of altered nucleic acid polymers with novel properties that
will become amenable through polymerase engineering.
12:00 Lunch on Your Own or
Luncheon Technology Workshop (Sponsorships Available)
1:10 Chairperson’s Remarks
1:15 Comparisons of PCR-Based Genome Amplification
Systems Using CpG Island Microarrays
Joseph Hacia, Ph.D., Biochemistry and Molecular Biology,
University of Southern California
The characterization of complex DNA
libraries providesa powerful approach towards characterizing
both genetic and epigenetic variation in genomes. However,
the value of such analyses is highly dependent upon the
quality of the DNA libraries themselves. For example, the
sequence composition of libraries made using PCR-based
procedures can be skewed due to biases in the amplification
efficiency of individual library members. We used CpG island
microarrays to evaluate the biases incurred in PCR-based
genome amplification using three different DNA polymerase
mixtures designed to efficiently amplify problematic
sequence tracts. Based on hybridization properties of
dye-labeled DNA libraries to these microarrays, we
quantified the overall and specific trends in the PCR
efficiency of more than 1,400 sequences with high
GC-content, which generally amplify with low efficiency
using conventional PCR protocols. Overall, all three DNA
polymerase mixtures produced libraries which show
substantial increases in the representation of CpG island
segments that poorly amplify with Taq DNA polymerase.
However, the effects of these DNA polymerases were quite
specific since they did not alter the relative
representation of segments that efficiently amplify with Taq
DNA polymerase. Finally, we applied these CpG island
microarray and library amplification strategies for
large-scale DNA methylation analyses in lymphomas. This has
lead to the identification of epigenetic biomarkers that may
be relevant for the early detection of disease.

1:45 Mitochondrial DNA Depletion Analysis by Pseudogene
Ratioing
Russell Swerdlow, M.D., Associate Professor, Neurology,
University of Virginia School of Medicine
Rho0 cell lines are cell lines completely
depleted of their mitochondrial DNA (mtDNA). mtDNA depletion
status of Rho0 cells is typically assessed by hybridization
or polymerase chain reaction (PCR) experiments, in which the
failure to hybridize mtDNA or amplify mtDNA using mtDNA-directed
primers suggests thorough mitochondrial genome removal. We
previously reported the use of an mtDNA pseudogene ratioing
technique for the additional confirmation of Rho0 status.
Total genomic DNA from a U251 human glioma cell line treated
with ethidium bromide (to deplete mtDNA) was amplified using
primers designed to anneal either mtDNA or a previously
described nuclear DNA-embedded mtDNA pseudogene (mtDNAø).
The resultant PCR product was used to generate plasmid
clones. Sixty-two plasmid clones were genotyped, and all
arose from mtDNAø template. These data allowed us to
determine with 95% confidence that the resultant mtDNA-depleted
cell line contains less than one copy of mtDNA per 10 cells.
Unlike previous hybridization or PCR-based analyses of mtDNA
depletion, this mtDNAø; ratioing technique does not rely on
interpretation of a negative result, and may prove useful as
an adjunct for the determination of Rgi0 status or mtDNA
copy number.
2:15 From Molecular Diagnostics to Individualized
Testing
Richard Y. Zhao, Ph.D., Associate Professor of Pathology,
Microbiology-Immunology and Human Virology, Division Head of
Molecular Pathology, and Director of Molecular Diagnostics
Laboratory, University of Maryland Medical Center
Gene-based molecular diagnostics is
changing the practice of medicine and will continue to do so
for the foreseeable future. The major underlying principle
of these diagnostic tests is the use of specific nucleic
acid sequences as surrogates; amplification of the surrogate
markers enables the detection of pathogens or disease
related gene mutations. Gene targets can be amplified by
target-, probe- or signal-based methods. Combined use of
nucleic acids amplification and ELISA with methods such as
immuno-PCR (iPCR) allows us to detect protein at femtogram
(10-15 g) levels. A variety of choices are available for the
detection of amplified amplicons with the fluorophore-linked
nanoparticles as the most sensitive markers. The unique
advantages of using covalently linked nanoparticles include
the detection of single molecules, the ability to enrich
molecules of interest with unprecedented detection
sensitivity (up to zeptogram, 10-21 g) and the flexibility
of multiple functionalization. Automation appears to be the
current trend for high volume molecular testing of
infectious diseases. Molecular profiling of various diseases
using genomic or proteomic approaches opens up a molecule
wonderland with promise and emergence of new molecular
testing that will likely impact the practice of medicine to
a greater degree in the future. The future of molecular
based testing and the journey toward personalized medicine
will be discussed.
2:45 Networking Refreshment Break, Poster and Exhibit
Viewing

3:15 Biodefense and Emerging Infectious Diseases
Research Repository—An Untapped Resource
Susan W. Jones, Ph.D., MFS, Collection Scientist,
Bacteriology, Biodefense and Emerging Infections Resource
Repository, American Type Culture Collection
This presentation will discuss the
growth, production and characterization of organisms and
nucleic acids produced in the Biodefense and Emerging
Infections Research Resource Repository (BEI Resources) NIH/NIAID
Funded repository located in the American Type Culture
Collection, Manassas, VA. BEI is a large repository research
resource located within the American Type Culture Collection
(ATCC) for select agent microbes, viruses, DNA, and other
research reagents. It is not as well known and these
resources are available to NIH/NIAID approved registrants of
BEI at no charge.
3:45 DNA-Microarray Analysis of Bacterial Pathogens
Relevant to Public Health
Nikolai Sergeev, Ph.D., Office of Science and Engineering
Laboratories, Division of Biological Sciences, U.S. Food
& Drug Administration
DNA-microarrays are a high-throughput
platform for the rapid and robust analysis of hundreds and
thousands of DNA sequences in one assay. The combination of
this technique with enzymatic amplification of genetic
material by PCR or WGA is a powerful tool for the detection,
identification, characterization of, and discrimination
among, various microbial pathogens of public health
relevance. In combination with bioinformatics, it opens up
new opportunities for developing more effective approaches
in diagnostics, treatment, tracking and prevention of
infectious diseases. Recent developments in microarray
technology have allowed for rapid microbial analysis in a
format adaptable to clinical, field, and laboratory use. The
results presented demonstrate the potential of DNA-microarrays
for the analysis of various bacterial pathogens and their
virulence factors relevant to safety of food, biologics,
reused medical devices and biodefense.
4:15 Combination of Immunosensor Detection with
Viability Testing and Confirmation Using PCR and Culture
Brandy J. Johnson, Ph.D., NRC Post Doctoral Associate,
Center for Bio/Molecular Science and Engineering, U.S. Naval
Research Laboratory
The Naval Research Laboratory Array
Biosensor provides rapid, automated analysis of multiple
samples for multiple targets in minutes. The sensor system
employs immobilized antibodies as recognition elements with
interrogation accomplished via total internal reflection
fluorescence spectroscopy. Immunosensors detect viable and
nonviable bacteria, fragments, and intact cells
indiscriminately making the formulation of a threat response
solely on the basis of this information impractical.
Traditional microbial techniques often require 24 hours or
more and do not identify non-viable or non-culturable
bacteria. PCR-based methods are more rapid and versatile
(completed in hours), but are limited by the number of
targets that can be distinguished and provide no information
on the viability of the identified microbes. This study
combines the rapid screening nature of the Array Biosensor
with methods for viability determination and further sample
characterization to minimize the limitations of the
available methods. The immunoassay provides a presumptive
identification of targets as well as concentrated samples
free of matrix contaminants. Culturing of captured cells
provides confirmation of viability in a shorter time frame
than traditional methods and provides samples for further
forensics investigations. Genetic analysis of captured
bacteria using PCR improves the sensitivity of array
biosensor by 3 orders of magnitude and can also provide
further information about the captured microbes. The work
demonstrates that this approach can be used to rapidly
detect and distinguish viable vs. nonviable and pathogenic
vs. nonpathogenic organisms, provide culture materials for
further analysis, and assess the effect of decontamination
protocols.
4:45 Closing Comments by Session Chairperson
5:00 Close of Conference
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