Transcript Duane L. Pierson, Ph.D. NASA Johnson Space Center Houston

Duane L. Pierson, Ph.D.
NASA Johnson Space Center
Houston, Texas
ADAPTATION TO SPACEFLIGHT
Psychological-BehavioralPerformance issues
Sleep and circadian
rhythm disturbances
Neurosensory adaptations
Taste and odor sensitivity
Cardiovascular adaptations
Gastrointestinal alterations
Fluid shifts,
hematological changes
Bone loss
Muscle loss
Immune changes
HUMAN IMMUNE RESPONSE
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Blood Cell Count
Lymphocyte Proliferative Responses
Cell Mediated Immunity
Cytokine Production
NK Cell Cytotoxicity
Humoral Factors
Specific Antibody Response
Wound Healing
Neutrophil Functions
FACTORS INCREASING DISEASE RISK
HEALTH
DISEASE
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Crowded Living Conditions
Closed-Loop Environment (Water/Air)
Reduced Capability for Personal Hygiene
Limited Clean-up and Disinfection Capability
Inability to Isolate Contagious Crewmember
Limited Treatment Capability and Crew Return
Altered Immune Response
INFECTIOUS DISEASE RISKS
• Skin Infections
• Gastrointestinal Distress
• Urinary Tract Infections
• Upper Respiratory
• Latent Viral Reactivation
WHY HERPESVIRUSES?
 Herpesviruses are the most readily recognized latent viruses.
 These viruses are ubiquitous and represent important
infectious disease risks with oncogenic potential.
 They are not mitigated by preflight quarantine.
 Space flight stress alters immune response.
 Diminished immunity results in reactivation and dissemination
(“shedding”) of latent viruses.
SPECIFIC APPLICATION
May be used as an early predictor of impending
medically significant changes in the immune response.
SALIVA COLLECTION PROCEDURE
Antarctica: EBV
4
Pre
Isolation
Post
Subject 1
Normal
3
2
Hypoergic
1
Anergic
0
-100
-50
0
50
100
150
Days in Isolation
200
250
DTH response
EBV DNA O.D. @ 405nm
5
Space Shuttle: EBV copies
EBV Copies per ml
1000
800
n = 32
Space Flights = 10
EBV Frequency:16%
EBV copies 417+ 31
•Control
•Mir
600
400
EBV Frequency: 29%
EBV copies 40+ 2
EBV Frequency: 16%
EBV copies 44+ 5
200
0
200-140 139-60 59-1
Day before launch
(L-)
2-4
5-7
Day of
flight
8-14
1-30 31-45
Day after recovery
(R+)
Space Shuttle: CMV Frequency
30
n = 71
25
20
15
10
5
0
n = 61
Astronauts
Control
CMV IgG Antibody Titers
CMV IgG Antibody Titers
(Mean +/- SE log2)
8
7
55 Astronauts
15 CMV Shedders
40 non-shedders
†
*
*
*
6
5
4
3
2
BL
L-10
R+0
R+3
* significant increase from BL (p<0.001)
† significant increase from L-10 (p< 0.001)
CONCLUSIONS
1. Space flight is a unique stress model
2. Antarctic Science Stations model many
aspects of space flight
3. Stress associated with space flight results in
increased reactivation of EBV, CMV and VZV.
4. Viral reactivation in astronauts appears to be
linked to duration in Space (Stress/
Microgravity ?).
5. Space flight associated stress manifested
through the HPA-axis result in increased
stress hormones, reduced CMI, and
increased viral reactivation.
ACKNOWLEDGEMENTS
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Satish K Mehta, Ph.D., NASA-JSC
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Desmond J. Lugg, M.D., Australian Antarctic Div, Hobart,
Australia
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Janet S. Butel, Ph.D., NSBRI/Baylor College of Medicine,
Houston,TX
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Randall J. Cohrs, Ph.D., Uni Colorado Health Sciences Center,
Denver Co
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Bagher Forghani, Ph.D.,California Department of Health
Services, Richmond, CA
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Stephen K. Tyring, M.D., Ph.D., UTMB, Galveston, TX
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Ronald Glaser, Ph.D., The Ohio State University, Columbus, OH