ScienCentral News
environment general science genetics health and medicine space technology May 06, 2003 
home NOVA News Minutes archive login

is a production of
ScienCentral, Inc.
Making Sense of Science

Also of Interest
Cancer-proof Mice (video)

Alzheimer’s Scans (video)

Drugs from the Deep (video)

Protein Machine (video)

Brain Viagra - Part 1 (video)

Brain Viagra - Part 2 (video)

Placebo Effect (video)

Good Fish, Bad Fish (video)

Slowing Alzheimer’s (video)

Birth Alert (video)

Older Women and Exercise (video)

Fat Attackers (video)

Brain Pills (video)

Rainbow X-Ray Vision (video)

Cognitive Behavioral Therapy (video)

NOVA News Minutes
Visit the NOVA News Minutes archive.
ScienCentral News and Nature
Nature genome promo logo
Don’t miss Enter the Genomeó
our collaboration with Nature.
Best of the Web!
Popular Science Best of the Web 2000
Selected one of Popular Science’s 50 Best of the Web.
Get Email Updates
Write to us and we will send you an email when a new feature appears on the site.
Cell Scouts (video)
August 28, 2002

Can’t see the movie above??
download realplayer logo
You can choose to either view it with a RealPlayer by clicking here.
Or get the free QuickTime player to view the higher-quality video above.

Interviewee: Hidde Ploegh, Harvard Medical School.

Video is 1 min 36 sec long. Please be patient while it loads enough to start playing.

Produced by Jack Penland

Copyright © ScienCentral, Inc., with footage from Harvard Medical School.

Also on ScienCentral News

Exploding Anthrax (video) - Thereís a new weapon in the war against anthrax, and it can can both detect it quickly and kill it. (8/21/02)

Yeast Vaccine (video) - Researchers may have found a vaccine effective against the AIDS virus. (7/25/01)

Mouse of a Different Color (video) - Researchers who turned white mice brown may have discovered an important key in understand gene expression. (6/21/01)

Elsewhere on the web

The Immune System - NIAID

Immune System/AIDS Topics - Library of Medicine

Show Me a DC-SIGN: Dendritic cells step into the spotlight - HIV Plus

It’s a short movie that will never make it to the big screen.

Nevertheless, it may have a big role in fighting disease.

This ScienCentral News video explains.

Smart cells

There’s a war going on over your body. Right now your body’s defenses are working to neutralize invading bacteria and viruses. Maybe you breathed them in. Maybe they got in through a wound in your skin. However they got in, those microbes are trying to multiply and take over. Fortunately for most people, the body is very good at defending itself.

But how does it all work? A study published in Nature magazine offers new information about how the body defends itself. It’s basic research that someday could lead to new ways to battle AIDS, combat organ rejection, and help the battle against other infections.

Researchers combined recently-discovered genetic techniques along with powerful microscopes to actually photograph one cell talking to another. According to Dr. Hidde Ploegh of the Harvard Medical School, "We can actually look at some of those events in a way that was not previously possible."

The chain of events works like this. At the forefront of your body’s defense system is a layer of cells called dendritic cells. Ploegh says these cells are a "rapid deployment force" against invading microbes that are "found throughout the body immediately underneath the skin very much like a coat of mail."

Scientists know that when a microbe enters the body, it will bump into one of these cells. The dendritic cells surround, absorb and chop up invading bacteria and viruses. But Ploegh and his associates were interested in what happens next.

"For us to defend ourselves against pathogens we need to recruit cells of the immune system to the appropriate location," he explains, "so that everyone gets together at the right place at the right time."

What the researchers showed was "to our astonishment…that from deep inside the cell fingers would shoot out to the contact site with the other cells (of the) immune system, as if there was almost like a secret handshake."

But before they could watch and photograph this process, they had to find a way to make the dendretic cells stand out. They took the gene that makes some jellyfish glow green and put that gene in a mouse, but in a new way so that only the dendritic cells glowed green.

Dr. Jonathan Yewdell, an immunologist at the National Institute of Allergy and Infectious Diseases pointed out that "this has never been done before in living tissue; the mouse is a living, three-dimensional map of where these dendritic cells are distributed."

The researchers then used powerful microscopes to actually watch and photograph the process happen in the mice.

Ploegh calls this basic research into how the immune system works "essential" in finding new ways to combat disease.

"We know the importance of the immune system," he says, "mostly because of what happens when it fails us." He points out that the HIV virus destroys cells of the immune system and that this research could offer new ways to fight the virus. He adds that organ transplants often fail because the immune system treats the transplant like an invading microbe and rejects it. Building on this discovery could lessen the number of rejections.

And, what about the mice? Says Yewdell, "They are very useful mice. We want them, lots of scientists will want them…they’re really cool mice."

by Jack Penland

About Search Login Help Webmaster
ScienCentral News is a production of ScienCentral, Inc.
in collaboration with the Center for Science and the Media.
248 West 35th St., 17th Fl., NY, NY 10001 USA (212) 244-9577.
The contents of these WWW sites © ScienCentral, 2000-2003. All rights reserved.
The views expressed in this website are not necessarily those of the NSF.
NOVA News Minutes and NOVA are registered trademarks of WGBH Educational Foundation and are being used under license.