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Ebola virus  (Source: zoonosesdiseases.com)
The team discovered a protein called Niemann-Pick C1 (NPC1), which they found was responsible for allowing Ebola virus to enter and replicate within cells

A team of scientists from different U.S. colleges and research institutes have discovered how and where Ebola virus enters a host cell, which has long been a mystery that deterred the creation of an effective vaccine.

Researchers from Whitehead Institute, Harvard Medical School, Albert Einstein College of Medicine and U.S. Army Medical Research Institute of Infectious Diseases have joined forces to better understand Ebola virus in order to eventually lead to the development of a vaccine that prevents Ebola hemorrhagic fever (EHF).

Ebola virus is classified as a category A bioterrorism agent by the U.S. Centers for Disease Control and Prevention (CDC). While Ebola virus outbreaks are rare, they can cause EHF and are extremely dangerous to humans. Those with EHF have symptoms such as fever, diarrhea, vomiting, intense weakness, joint and muscle pain, and sometimes external or internal bleeding due to the disintegration of blood vessels.

While the symptoms of EHF can be treated, there is currently no vaccine to prevent it. According to the World Health Organization (WHO), there have been 1,850 EHF cases with 1,200 deaths since the virus was found in 1976.

"Right now, people make therapeutics to inactivate the pathogen itself," said Thijn Brummelkamp, former Whitehead Fellow and current leader at the Netherlands Cancer Institute (NKI). "But the problem is that pathogens can quickly change and escape detection and elimination by the immune system. Here we get a good idea of the host genes that are needed for the pathogen to enter the cell for replication. Perhaps by generating therapeutics against those host factors, we would have a more stable target for antiviral drugs."

The team of researchers discovered how Ebola virus gained entry into a host cell by using an unusual human cell line. All humans receive one copy of each chromosome from each parent, but cell lines have a single set instead with only one copy of each individual gene. Researchers wanted to use gene disruption, which "knocks out" a gene function in host cells one-by-one, to  silence one copy of a gene.

Researchers used a technique that team member Jan Carette, of the Brummelkamp lab at Whitehead Institute, utilized while studying the cytolethal distending toxin (CDT) family. The CDT family secretes several pathogenic bacteria such as Escherichia coli, and each bacterial species has created different mutations of the CDT structure. Using a line of haploid cells, or KBM7 cells, which have only one copy of each chromosome and were isolated from a chronic myeloid leukemia patient, researchers could disrupt the expression of each gene while screening for mutants that had certain characteristics (specifically, those who could survive a lethal dose of the toxin).

While disrupting the normal structure of the gene, mutant KBM7 cells were exposed to the toxins and those that survived were studied. In the end, after studying the surviving cells' genomes, researchers were able to find ten human proteins used by CDT's during intoxication. Also, the host cells were adjusted for each CDT's target cell.

The research team utilized this same technique for Ebola virus using an unusual human cell line. Through the use of a harmless virus covered in the Ebola virus glycoprotein and the alteration of the haploid cells, the team discovered a protein called Niemann-Pick C1 (NPC1), which they found was responsible for allowing Ebola virus to enter and replicate within cells. The mutations of this gene cause a type of Niemann-Pick disease.

The effects of the active Ebola virus were tested on mice who had a knocked-out copy of the NPC1 gene and mice with two functioning NPC1 genes. Those with two functioning NPC1 genes were affected by the virus very quickly while those with a knocked-out NPC1 gene were significantly protected.

"This is pretty unexpected," said Carette. "This might imply that genetic mutations in the NPC1 gene in humans could make some people resistant to this very deadly virus. And now that we know that NPC1 is an Ebola virus host factor, it provides a strong platform from which to start developing new antivirals."

This study was published in Nature.


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it could be used for good
By dgingeri on 8/25/2011 6:52:06 PM , Rating: 2
They could potentially alter it just right so that it only enters cancer cells, then it could be our cure for cancer.

something to think about...




RE: it could be used for good
By Spuke on 8/25/2011 7:03:00 PM , Rating: 2
You first. Sorry but that's the nastiest sh!t on the planet. No way! F$&k that!


RE: it could be used for good
By Mitch101 on 8/25/2011 9:07:18 PM , Rating: 2
How bout this one? $8.95 & eligible for FREE Super Saver Shipping
http://www.amazon.com/Giant-Microbes-Ebola-Virus/d...


RE: it could be used for good
By NicodemusMM on 8/25/2011 7:19:55 PM , Rating: 3
Good point, but while thinking about it I can't stop thinking about the movie "I Am Legend" at the same time.

~ Nicodemus


RE: it could be used for good
By vol7ron on 8/25/2011 11:14:31 PM , Rating: 2
One thing we've learned is that nature mutates. I don't want Ebola, Cancer, or AIDS coming anywhere near each other.


RE: it could be used for good
By Omega215D on 8/26/2011 3:52:32 AM , Rating: 2
House: Now where's the fun in that?

Throw in some lupus to be sure...


RE: it could be used for good
By tastyratz on 8/26/2011 8:59:55 AM , Rating: 2
sarcoidosis?


RE: it could be used for good
By Raraniel on 8/26/2011 11:15:53 AM , Rating: 3
Why is it that XKCD has an appropriate response for any situation?

http://www.xkcd.com/938/


RE: it could be used for good
By Adonlude on 8/26/2011 6:52:33 PM , Rating: 2
Becuase then you'd have Cebolaids, and that's no fun for anyone.


RE: it could be used for good
By Mudhen6 on 8/25/2011 11:05:51 PM , Rating: 2
If there was a sure-fire way to discriminate cancer cells from other cells, cancer would've been cured already.

Cancer cells are like snowflakes - they're all different. Even the cancer cells in a tumor. In fact, think of the tumor as one giant, Darwinian experiment ("Survival of the fittest"). Each cancer cell is continuously mutating and duplicating.

The cancer cells with the crappy mutations get killed by drugs and white blood cells. The ones that are fit continue duplicate, and continue to mutate.

That's why cancer is such a tough-son-of-a-b!tch. If you're drug/treatment isn't 100% effective, then you're just selecting cancer cells of the greatest fitness. Furthermore, cancer cells are still human cells, thus making them very difficult to attack without severe side-effects.


RE: it could be used for good
By Mudhen6 on 8/25/2011 11:09:09 PM , Rating: 2
"Even the cancer cells in a tumor" I meant "Cancer cells just don't vary from person to person, or tumor to tumor, but vary on a cell to cell level, within a single tumor, from person to person."


RE: it could be used for good
By geddarkstorm on 8/26/2011 12:19:45 PM , Rating: 2
It's less of a Darwinian experiment and more of a "oh crap, our check point system just had a BSOD and now our chromosomes are snapping, fusing, and duplicating in wildly uncontrollable, unstable ways!"

Put another way: cancer cells don't outcompete our normal cells, because our normal cells aren't trying to compete in the first place--they are trying to work together synergistically to maintain our multicellular bodies. So in truth, cancer cells are not as fit as normal cells since they've lost this vital ability, and the more aggressive less capable of team work they are, the less fit they are for survival.

After all, in the end, they die right along with you ;).


RE: it could be used for good
By Mudhen6 on 8/26/2011 3:32:36 PM , Rating: 3
They do compete with normal cells, but perhaps not in the classic sense. They're basically as*hole cells that route local blood vessels to feed the tumor, dominating local tissues.

They don't give a f**k about teamwork or long-term survival, thus in the short-term, cellular perspective they are able to out-compete non-cancerous cells whose programming relies on teamwork rather than self-perpetuation.


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