A Space & astronomy forum. SpaceBanter.com

Go Back   Home » SpaceBanter.com forum » Space Science » Space Station
Site Map Home Authors List Search Today's Posts Mark Forums Read Web Partners

Study suggests spaceflight may decrease human immunity



 
 
Thread Tools Display Modes
  #1  
Old September 29th 04, 07:21 PM
Jacques van Oene
external usenet poster
 
Posts: n/a
Default Study suggests spaceflight may decrease human immunity

Dolores Beasley Sept. 29, 2004
Headquarters, Washington
(Phone: 202/358-1753)

William Jeffs
Johnson Space Center, Houston
(Phone: 281/483-5111)

RELEASE: 04-320

STUDY SUGGESTS SPACEFLIGHT MAY DECREASE HUMAN IMMUNITY

A NASA-funded study has found the human body's ability
to fight off disease may be decreased by spaceflight. The
effect may even linger after an astronaut's return to Earth
following long flights.

In addition to the conditions experienced by astronauts in
flight, the stresses experienced before launch and after
landing also may contribute to a decrease in immunity.

Results of the study were recently published in "Brain,
Behavior, and Immunity." The results may help researchers
better understand the affects of spaceflight on the human
immune response. They may also provide new insights to ensure
the health, safety and performance of International Space
Station crewmembers and future spacefarers on extended
missions.

"Astronauts live and work in a relatively crowded and
stressful environment," said Duane Pierson, the study's
principal investigator and NASA Senior Microbiologist at
Johnson Space Center, Houston. "Stresses integral to
spaceflight can adversely affect astronaut health by
impairing the human immune response. Our study suggests these
effects may increase as mission duration and mission activity
demands increase," he added.

The white blood cell count provides a clue to the presence of
illness. The five main types of white cells work together to
protect the body by fighting infection and attacking foreign
material. The most prevalent white blood cells are called
neutrophils.

From 1999 to 2002, scientists from NASA, Enterprise Advisory
Services, Inc., of Houston, and the Boston University School
of Medicine compared neutrophil functions in 25 astronauts.
They made comparisons after five-day Space Shuttle missions
and after nine to 11 day missions.

Researchers found the number of neutrophils increased by 85
percent at landing compared to preflight levels. Healthy
ground control subjects, who did not fly, exhibited no more
than a two percent increase. Researchers also discovered
functions performed by these cells, specifically ingestion
and destruction of microorganisms, are affected by factors
associated with spaceflight. The effect becomes more
pronounced during longer missions.

The increase in astronaut neutrophil numbers resulted in a
corresponding increase (more than 50 percent) in total white
blood cell counts at landing. The increase is a consistent
consequence of stress.

Pierson emphasized that "no astronauts in the study became
ill; however, longer exploration missions may result in
clinical manifestations of decreased immune response."

Researchers concluded the general effect of spaceflight, pre-
and post flight-related stress decreases the ability of
crewmembers' neutrophils to destroy microbial invaders. This
finding suggests crewmembers returning from longer missions
may be briefly more susceptible to infections than before
launch, because these cells are not as efficient in ingesting
and destroying infectious agents.

"Having a better understanding of the impact of stress on
immunity will help us better understand the risks of
infectious disease for Space Station crewmembers and future
travelers on long-duration missions," Pierson said.

For information about NASA's space research on the Internet,
visit:

http://spaceresearch.nasa.gov/

-end-


--
---------------------------

Jacques :-)

www.spacepatches.info



 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Breakthrough in Cosmology Kazmer Ujvarosy Space Shuttle 3 May 22nd 04 09:07 AM
Breakthrough in Cosmology Kazmer Ujvarosy Space Station 0 May 21st 04 08:02 AM
Plain talking on the Hill Allen Thomson Policy 23 October 19th 03 02:18 PM
Talk to Congress about Commercial Human Spaceflight Edward Wright Policy 16 October 14th 03 12:20 AM
Congress Subcommittee Hearing on Commercial Human Spaceflight Centurion509 Policy 0 July 23rd 03 01:30 AM


All times are GMT +1. The time now is 11:47 AM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 SpaceBanter.com.
The comments are property of their posters.