?

Log in

No account? Create an account

Previous Entry | Next Entry

Or in other words, they are a natural part of our immune defense! New science suggests that mucus in our body is full of viruses that attack bacteria! Those viruses don't hurt us, in fact, they protect us. Commensal viruses....

Viruses and mucus team up to ward off bacteria | Life
Phages may play unforeseen role in immune protection
By Tina Hesman Saey
Web edition: May 20, 2013

The last thing most people would want in their bodies is mucus laden with viruses. But a new study suggests that viruses called bacteriophages, or phages, grab onto mucus and then infect and kill invasive bacteria. The finding, reported May 20 in the Proceedings of the National Academy of Sciences by Forest Rohwer of San Diego State University and colleagues, could mean that some viruses partner with animals and humans to stave off bacterial infections and control the composition of friendly microbes in the body.

Bacteriophages are viruses that break open bacteria, killing them. Researchers have studied bacteriophages for decades, and some disease therapies take advantage of the viruses' bacteria-slaying abilities, says microbiologist Frederic Bushman of the University of Pennsylvania medical school. But the study provides what Bushman says is a revelation that should have been obvious; phage may be a natural part of the immune system. "It's new in a way that is sort of common-sensey," he says.

Previously, researchers thought of mucus mainly as a physical barrier to keep invading organisms from entering the body. The slimy substance made by our noses, intestines and other organs also fights invaders with antimicrobial molecules. Some researchers had found bacteriophages stuck in mucus, but they figured that the mucus had stopped or slowed the viruses. No one realized that the viruses are part of the body's defense, says study coauthor Jeremy Barr, who works in Rohwer's lab. "This is a natural use of phage therapy that has probably been around since mucosal surfaces evolved," Barr says.

Rohwer, who studies corals, had noticed that phages tend to concentrate in mucus. To find out why, the researchers collected mucus from human gums, sea anemones, fish, corals and mouse intestines. Mucus layers had more phages and fewer bacteria than the surrounding environment, suggesting that the viruses helped to limit the number of bacteria allowed into the mucus.

Phages are coated in proteins that latch onto sugars called glycans, anchoring the viruses in the mucus, the team discovered. From there the phages can ambush encroaching bacteria.

So far, the researchers have demonstrated that mucus and phages can work together to protect cells in a dish. The next step, Bushman says, would be determining what happens inside an organism, an experiment the researchers are already planning.

Comments

( 13 comments — Leave a comment )
ford_prefect42
May. 22nd, 2013 03:03 am (UTC)
Philosophy.
And are bacterio-phages "alive"? Complex molecules that disrupt the replication of subsystems of viri, causing replication of the original molecule instead. Is that molecule a life? Scientifically, if it can be remotely considered alive, even by the most exotic definition, then how can any debate exist about whether or not a 2 month old fetus is "alive"? Hell, that's got a central nervous system!
liveonearth
May. 22nd, 2013 03:09 am (UTC)
Re: Philosophy.
Bacteriophages are viruses. Phages are viruses. It has long been debated whether viruses are "alive" because they do not have the machinery to survive or reproduce independently. However they do take over the command centers of our cells, and insert their genetic code into ours, and that of every other living thing. So no matter whether or not they are "alive"....they are a force to be contended with!

PS, where'd you get that "complex molecule" definition?
ford_prefect42
May. 22nd, 2013 03:18 am (UTC)
Re: Philosophy.
"complex molecule"

In the most literal of all possible ways, what else can a phage be defined as?

eta.

Given that viri, phages, bacteriophages, etcetera, have long been debated within the medical and scientific community as "possibly life", what room for debate remains about a fetus? Given that the only possible answer with any logical consistency is "none", how is anyone calling RTL people "ignorant" solely for that position? Where exactly does the pro choice position garner philosophical underpinnings?

Edited at 2013-05-22 03:28 am (UTC)
liveonearth
May. 22nd, 2013 04:01 am (UTC)
Re: Philosophy.
I believe that they are made up of more than one molecule, and the molecules that comprise them have varying complexity. There is a capsule made of proteins, and a genome made of DNA and RNA in a range of sizes.

As for your more philosophical and political questions, sorry. Let me only say that I believe life to be a continuous process, and not something that "begins" at any one time in the womb. If you'd like to actually read my thinking about abortion, I have a tag for it and plenty out there that you can read and tear to shreds if you so desire.
madman101
May. 22nd, 2013 03:50 am (UTC)
i also saw that and may yet post - note that phage research has been big in russia but neglected here

of interest to me - pic of phases - cool shapes


Friendly Viruses Protect Us Against Bacteria
http://news.sciencemag.org/sciencenow/2013/05/friendly-viruses-protect-us-agai.html
liveonearth
May. 22nd, 2013 03:54 am (UTC)
Yep. The Soviets used 2 tons/day of phage in wartimes, and you know they don't waste money. Works great for wound care. There's a hospital in Georgia (former USSR republic) where phage therapy saves lives and limbs regularly.
madman101
May. 22nd, 2013 04:02 am (UTC)
Those Russians are so impressive... and yet strange.

There is some debate as to whether they are really alive.

;D

Goodnight. Thanks for the post.
rick_day
May. 22nd, 2013 06:41 am (UTC)
boogers for good health? Don't expectorate, swallow?

idk....
liveonearth
May. 22nd, 2013 05:16 pm (UTC)
Ick! You gross me out too.
newedition
May. 22nd, 2013 12:54 pm (UTC)
Very fascinating! Definitely incorporating this into the Microbiology class next fall. :-)
Also wondering if this could be the key to "auto-immunity"-- maybe our body is mis-recognizing the helpful virus as bad and attacking our own cells which contain the virus?
liveonearth
May. 22nd, 2013 05:22 pm (UTC)
Wellllllll actually the triggers for AI dz are pretty well known and viruses are not at the top of our worries list. More commonly it occurs because of "leaky gut" which activates the immune system to recognize (and attack) epitopes which should be considered "food" or "self". Some people have HLA markers on their cells that are very much like food, esp gluten, and they are highly susceptible to a failure of immune tolerance.

The phages in our mucus are there because there is a constant stream of food for them. Phages tend to be very specific: one particular type of bacteriophage will infect one particular type of bacterium. Phage therapy involves finding the right one to attack the bacteria involved...and nature does this for us. The lovely thing is that when the bacterium isn't available, phage populations specific to it naturally reduce.
newedition
May. 23rd, 2013 02:08 am (UTC)
Hm, that's interesting! I knew leaky gut could lead to food sensitivity, particularly gluten and casein, but hadn't heard about the mimicry with components of our own system. It's a wonderfully interesting world!
liveonearth
May. 28th, 2013 07:56 pm (UTC)
HLA-DQ2 and HLA-DQ8 seem to be the two cell markers that tangle with gluten. The glutein protein getting to the immune system via failing tight junctions in the intestinal wall is what seems to trigger an assortment of AI disease.
( 13 comments — Leave a comment )

Profile

moon
liveonearth
liveonearth

Latest Month

December 2017
S M T W T F S
     12
3456789
10111213141516
17181920212223
24252627282930
31      

Tags

Powered by LiveJournal.com
Designed by chasethestars