Transcript Biodefense Against Infectious Disease - Bio-Rad

Biodefense
Detection to Protect the Nation
Frank Y. S. Chuang & Dora M. Gutierrez
Lawrence Livermore National Laboratory
J. Kirk Brown
Tracy High School
UCRL-PRES-204341
Main Questions

What are germs?

Why are they dangerous?

How do we recognize them?

How can we protect ourselves
against them?
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.
Achievements in
Infectious Disease Medicine


Vaccines - cause the body
to become immune to
infectious disease
Antibiotics - kill or stop
germs that cause
infectious disease
Max. cases
Measles
894,000
(1941)
500
Diptheria
207,000
(1921)
1
Mumps
152,000
(1968)
600
Edward Jenner
1749 - 1823
Used cowpox to protect
against smallpox.
(“Vaccination” from
Latin vacca for cow.)
Cases in
1996
Disease
Louis Pasteur
1822 - 1895
French chemist who
discovered “germ theory
of infectious disease” &
demonstrated the
benefits of sterilization.
So - why worry?
New Biological Threats
Severe Acute Respiratory Syndrome (SARS)
Bacillus anthracis (anthrax)
Speed of Epidemic Outbreak
Destructive power of germs
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
2,000,000
70,000
Recent Human Epidemics
# of deaths




Atomic
Jewish Spanish Flu
Bomb
Holocaust
of
(Hiroshima)
WWII
1918

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
Types of germs
Staphylococcus aureus
Escherichia coli
Bacillus anthracis
Smallest singlecelled organism.
Able to replicate
outside the body.
~ 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
Bacteria
~ 1 micron
Viruses
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
Viral Infection I - Invading host cell
Viral Infection II - Replication of virus
Viral Infection III - Host cell lysis
The Immune System
The body’s natural defense against foreign
and/or infectious agents:
– Skin
– White blood cells
– Antibodies
Phagocytes “eat” and destroy bacteria.
Antibodies recognize and
bind to epitopes of foreign
molecules (antigens).
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.
QuickTime™ and a
GIF decompressor
are needed to see this picture.
Immune System: White Cells

White blood cells
– macrophages
– neutrophils
– lymphocytes
T-lymphocytes use
antibodies to recognize
and destroy infected cells.
use either native or adaptive
QuickTime™ and a
Cinepak
decompressor
immunity
to destroy
are needed to see this picture.
infectious agents.
QuickTime™ and a
Video decompressor
are needed to see this picture.
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.
Methods of Biodetection
Laboratory culture
& microscopy
Immunoassay
(ELISA)
DNA hybridization
& sequencing
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
How can we make him easier to spot?
Paint him bright purple??
???
Make him glow-in-the-dark !!
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
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.
Methods of Biodetection
New methods detect
molecules associated with
germs, instead of germs
themselves.
Immunoassay
(ELISA)
DNA hybridization
& sequencing
Advantages: very
sensitive, results in 1-3
hours, no need for
microscope
Disadvantages: ?
Advanced Biodetection
Need for better technology:





Faster results
More accurate (no false
readings)
Higher throughput
Cost-efficient
Automatic
Bead-Based Sandwich Immunoassay
Fluorescent reporter molecule binds to microbead
only in the presence of targeted antigen.
Bead schematics courtesy of Luminex Corp. <http://www.luminexcorp.com/tech/>
Multiplex Optical Encoding
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.
Analyzing the Microbeads
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
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
Biodefense - A Multidisciplinary Field
 Discovery through basic research
 Innovative biotechnology
 Excellent clinical medicine
Basic Science Research
Basic scientists
 biologists
 chemists
 physicists
discover new
mechanisms of disease
that could offer new
ways to detect or treat
infectious disease.
Bioengineering & Biotechnology
Engineers
 electrical
 mechanical
 computer
apply scientific knowledge
to develop new medical
technologies.
Clinical Medicine
QuickTime™ and a
TIFF (LZW) decompressor
are needed to see this picture.
Doctors are the first to
respond to infectious
disease, and also
guide the direction of
future research and
development.
Conclusions

Biodefense is everyone’s 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..!
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