Biodefense Detection to Protect the Nation

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BiodefenseDetection to Protect the Nation

• Frank Y. S. Chuang Dora M. Gutierrez
• Lawrence Livermore National Laboratory
• J. Kirk Brown
• Tracy High School

UCRL-PRES-204341
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Main Questions

• What are germs?
• Why are they dangerous?
• How do we recognize them?
• How can we protect ourselves against them?

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Introduction

• Throughout history, infectious disease has
  plagued mankind.
• Smallpox may have emerged 10,000 years ago in
  Asia or Africa. Scarred faces of mummies can be
  found in the Cairo Museum.

Smallpox is caused by the variola virus.
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Achievements in Infectious Disease Medicine

• Vaccines - cause the body to become immune to
  infectious disease
• Antibiotics - kill or stop germs that cause
  infectious disease

Disease Max. cases Cases in 1996
Measles 894,000 (1941) 500
Diptheria 207,000 (1921) 1
Mumps 152,000 (1968) 600
Louis Pasteur 1822 - 1895 French chemist who
discovered germ theory of infectious disease
demonstrated the benefits of sterilization.
Edward Jenner 1749 - 1823 Used cowpox to protect
against smallpox. (Vaccination from Latin vacca
for cow.)
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So - why worry?
New Biological Threats
Severe Acute Respiratory Syndrome (SARS)
Bacillus anthracis (anthrax)
Speed of Epidemic Outbreak
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Destructive power of germs
Recent Human Epidemics
20,000,000 18,000,000 16,000,000 14,000,000 12,000
,000 10,000,000 8,000,000 6,000,000 4,000,000 2,00
0,000 70,000
of deaths

• Severe Acute Respiratory Syndrome (SARS)
  Asia, Canada, U.S. 2003
• Anthrax United States, Oct.
  2001
• West Nile Virus United States 1999 - ?
• Ebola hemorrhagic fever Gabon 2001
• Meningococcal disease Ethiopia 2001

Atomic Bomb (Hiroshima)
Jewish Holocaust WWII
Spanish Flu of 1918
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Types of germs
Bacteria 1 micron Staphylococcus aureus Escherichia coli Bacillus anthracis Smallest single-celled organism. Able to replicate outside the body.
Viruses 100 nanometers Influenza Variola (smallpox) HIV/AIDS Packets of genetic material -- requires host cell to replicate.
Fungi Mushrooms, mold (aspergillus) Not all are harmful to human health
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Viral Infection I - Invading host cell
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Viral Infection II - Replication of virus
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Viral Infection III - Host cell lysis
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The Immune System

• The bodys natural defense against foreign and/or
  infectious agents
• Skin
• White blood cells
• Antibodies

Antibodies recognize and bind to epitopes of
foreign molecules (antigens).
Phagocytes eat and destroy bacteria.
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Immune System Antibodies

• Antibodies help recognize foreign material in the
  body.
• Anything that antibodies stick to will be
  attacked by the immune system.
• Healthy individuals carry trillions of different
  antibodies in the bloodstream.

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Immune System White Cells

• White blood cells
• macrophages
• neutrophils
• lymphocytes
• use either native or adaptive immunity to
  destroy infectious agents.

T-lymphocytes use antibodies to recognize and
destroy infected cells.
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War against germs

• The immune system works constantly to keep
  infectious microbes in check.
• Germs that can bypass or overwhelm primary
  defenses cause infectious disease.
• Early detection of infectious disease is often
  the key to preventing widespread outbreak.

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Methods of Biodetection
Laboratory culture microscopy
Immunoassay (ELISA)
DNA hybridization sequencing
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Methods of Biodetection
Procedure put clinical sample in incubator and
wait for germs to grow. Look for germs under
microscope. Advantage Laboratory Gold
Standard Disadvantage Results take 7-10 days
Laboratory culture microscopy
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How can we make him easier to spot?
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Paint him bright purple??
???
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Make him glow-in-the-dark !!
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Immunoassays

• Antibodies can be used to identify germs
• Fluorescent labels allow us to locate antibodies
  without having to see germs
• Capture antibody layer targeted germs
  reporter antibody layer Sandwich Immunoassay

Fluorescent Reporter Antibodies
Targeted germs
Capture Antibodies
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Enzyme-linked Immunosorbent Assay (ELISA)
Positive test
ELISA is also known as a sandwich assay --
because the antibody and antigen layers are
stacked like a sandwich.
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Methods of Biodetection
New methods detect molecules associated with
germs, instead of germs themselves. Advantages
very sensitive, results in 1-3 hours, no need for
microscope Disadvantages ?
Immunoassay (ELISA)
DNA hybridization sequencing
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Advanced Biodetection

• Need for better technology
• Faster results
• More accurate (no false readings)
• Higher throughput
• Cost-efficient
• Automatic

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Bead-Based Sandwich Immunoassay
Fluorescent reporter molecule binds to microbead
only in the presence of targeted antigen.
Bead schematics courtesy of Luminex Corp.
lthttp//www.luminexcorp.com/tech/gt
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Multiplex Optical Encoding
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Multiplex Immunoassay
100 bead classes 100
immunoassays
influenza
adenovirus
RSV
anthrax
etc...
Optically encoded beads allow multiple tests to
be run on a single sample.
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Analyzing the Microbeads
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Potential biodefense applications

• Hospital-based flow cytometer systems
• High-throughput screening of clinical samples
• Handheld point-of-care instruments
• Local clinic or paramedic first responder use
• Autonomous monitoring systems
• For continuous surveillance in strategic
  environments

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Autonomous Pathogen Detection System (APDS)

• Completely autonomous
• Sample, concentrate, detect, identify and report.
• Multiplex detection
• Up to 100 discrete channels.
• Detects all bioagent types
• Bacterial spore / virus / toxin

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Biodefense - A Multidisciplinary Field

• Discovery through basic research
• Innovative biotechnology
• Excellent clinical medicine

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Basic Science Research

• Basic scientists
• biologists
• chemists
• physicists
• discover new mechanisms of disease that could
  offer new ways to detect or treat infectious
  disease.

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Bioengineering Biotechnology

• Engineers
• electrical
• mechanical
• computer
• apply scientific knowledge to develop new medical
  technologies.

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Clinical Medicine
Doctors are the first to respond to infectious
disease, and also guide the direction of future
research and development.
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Conclusions

• Biodefense is everyones business. Public
  awareness is the first step towards prevention.
• No solution lasts forever. Science and
  technology must adapt to cope with the evolving
  nature of infectious disease.
• Future advances in biomedical research depend on
  experts in all disciplines..!

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Acknowledgements

• LLNL M-Division Medical Physics Biophysics
• Candice Cook
• Christine Paulson
• Christine P. Nguyen
• Ben Hindson
• John T. Chang
• Steven R. Visuri
• Mary T. McBride
• Kodumudi Venkateswaran
• Bill W. Colston, Jr.

• UC Davis Medical Center
• James Carlson, Ph.D. (Clinical Microbiology)
• Robert Derlet, M.D. (Emergency Medicine)
• Luminex Corporation
• Education Outreach - LLNL
• Marsha McInnis
• Jason Windsor