How gut bacteria escape detection

[Roman Byst]

http://www.healthsentinel.com/news.php?event=news_print_list_-
item&id=692

"How gut bacteria escape detection", BBC News, March 21, 2005,
Link: http://news.bbc.co.uk/1/hi/health/4358285.stm

Bacteria living in the human intestine escape detection by the
immune system by disguising themselves as gut cells,
researchers say.

A US team examined bacteria from the genus Bacteroides - the
most commonly found bacteria in the human gut.

They found the bacteria wrap themselves in a sugar
substance derived from molecules taken from the surface of
cells in the gut.

Details of the Harvard Medical School research are in the
journal Science.

This form of molecular mimicry may help to explain how humans
tolerate the presence of billions of bacteria in the gut
without launching an immune system attack.

The Harvard team found that Bacteroides bacteria coat
themselves with a form of fucose, a molecule which is abundant
on the surface of intestinal epithelial cells.

Previous research has shown that Bacteroides can
stimulate intestinal epithelial cells to produce
molecules such as fucose.

It now seems that the bacteria are then able to incorporate
this molecule in a slightly modified form directly into their
own cells.

Digestive role

Bacteroides play a crucial role in the digestive process,
helping to break down food products and supplying some
vitamins and other nutrients that we cannot make ourselves.

Researcher Dr Laurie Comstock told the BBC News website:
"Compared to the wealth of knowledge regarding mechanisms
used by bacterial pathogens to cause disease, relatively
little is known about how the trillions of bacteria in the
mammalian intestine establish and maintain beneficial
relationships with the host.

"It is extremely important that the resident bacteria in our
intestine do not generate a deleterious immune response.

"Bacteroides are able to degrade a great variety of
plant polysaccharides so that the host is able to use
them for energy.

"Many of these plant polysaccharides could not be used by the
host without the aid of the bacteria."

Dr Alastair Forbes, a consultant gastroenterologist at St
Mark's Hospital, London, said the findings were interesting.

He said it was possible they could be used in the long-term to
develop new forms of probiotic treatment for gastrointestinal
disorders.

Probiotics, preparations containing beneficial bacteria, have
already been used to treat conditions such as ulcerative
colitis and pouchitis.

"The use of probiotics has had some success, but their use is
made difficult by the fact that the bugs tend not to persist
in the gut, and treatments have to be given week after week,"
Dr Forbes said.

"If there was some way of modifying bacteria so they
could continue to infect the gut, but remain safe, that
would be useful."

Dr Forbes said scientists were also working on prebiotic
treatments, which provide nutrients to encourage the growth of
certain bacteria.

However, he said knowledge about the bacteria which live in
the gut was still relatively limited.

It is estimated that only about 20-30% of the bacteria that
inhibit the gut have been identified.

[Montygram]

No question one wants the "good bacteria" in the gut, but this
report makes it seem like any bacterium or virus is going to
get slammed by the "immune system." In reality, there are more
bacteria cells than human cells in the human body. In mice,
and probably mammals in general, there are hundreds (if not
thousands) of different kinds of one class of virus
(retroviruses). The key question is how do various things
prompt an "autoimmune resposnse," and here the evidence points
to arachidonic acid excess, which is why the usual crowd is
hawking fish oil - it interferes with arachidonic acid
metabolism (though not without charging a very high price -
lipid peroxidation). Instead, if you avoid more than trace
amounts of polyunsaturated fatty acids, you probably won't
have to worry about any of this kind of thing.

[Robert]

"montygram" <nazztrader@lycos.com> wrote in message
news:1111468838.750904.74560@o13g2000cwo.googlegroups.com...
> No question one wants the "good bacteria" in the gut, but
> this report makes it seem like any bacterium or virus is
> going to get slammed by the "immune system." In reality,
> there are more bacteria cells than human cells in the human
> body. In mice, and probably mammals in general, there are
> hundreds (if not thousands) of different kinds of one class
> of virus (retroviruses). The key question is how do various
> things prompt an "autoimmune resposnse," and here the
> evidence points to arachidonic acid excess, which is why the
> usual crowd is hawking

Learn how to read please. It does not mention "autoimmune". It
mentions an immune response that is lacking against bacteria
present in the gut.

> fish oil - it interferes with arachidonic acid metabolism
> (though not without charging a very high price - lipid
> peroxidation). Instead, if you avoid more than trace amounts
> of polyunsaturated fatty acids, you probably won't have to
> worry about any of this kind of thing.
>
What in the world are you talking about? Where is AA or
polyunsaturated fats mentioned in this article? Get a grip on
yourself man. You sound like a broken record.

[Tc]

Interesting stuff.

Kinda sad that the first reaction of the "scientist" is to
suggest scenarios where they can create "probiotics" or
"probiotic processes" that can be sold and marketted as
treatments. Sounds more like a marketer than a scientist.

They should be considering what diets encourage and/or
discourage the right balance of good bacteria in the gut.
Treat the problem at its source, eh?

TC

Roman Bystrianyk wrote:
>
http://www.healthsentinel.com/news.php?event=news_print_list_-
item&id=692
>
> "How gut bacteria escape detection", BBC News, March 21,
> 2005, Link: http://news.bbc.co.uk/1/hi/health/4358285.stm
>
> Bacteria living in the human intestine escape detection by
> the immune system by disguising themselves as gut cells,
> researchers say.
>
> A US team examined bacteria from the genus Bacteroides - the
> most commonly found bacteria in the human gut.
>
> They found the bacteria wrap themselves in a sugar substance
> derived from molecules taken from the surface of cells in
> the gut.
>
> Details of the Harvard Medical School research are in the
> journal Science.
>
> This form of molecular mimicry may help to explain how
> humans
tolerate
> the presence of billions of bacteria in the gut without
> launching an immune system attack.
>
> The Harvard team found that Bacteroides bacteria coat
> themselves with
a
> form of fucose, a molecule which is abundant on the surface
> of intestinal epithelial cells.
>
> Previous research has shown that Bacteroides can
> stimulate intestinal epithelial cells to produce
> molecules such as fucose.
>
> It now seems that the bacteria are then able to incorporate
> this molecule in a slightly modified form directly into
> their own cells.
>
> Digestive role
>
> Bacteroides play a crucial role in the digestive process,
> helping to break down food products and supplying some
> vitamins and other nutrients that we cannot make ourselves.
>
> Researcher Dr Laurie Comstock told the BBC News website:
> "Compared to the wealth of knowledge regarding mechanisms
> used by bacterial pathogens to cause disease, relatively
> little is known about how the trillions of bacteria in the
> mammalian intestine establish and
maintain
> beneficial relationships with the host.
>
> "It is extremely important that the resident bacteria in our
intestine
> do not generate a deleterious immune response.
>
> "Bacteroides are able to degrade a great variety of
> plant polysaccharides so that the host is able to use
> them for energy.
>
> "Many of these plant polysaccharides could not be used by
> the host without the aid of the bacteria."
>
> Dr Alastair Forbes, a consultant gastroenterologist at St
> Mark's Hospital, London, said the findings were interesting.
>
> He said it was possible they could be used in the
> long-term to
develop
> new forms of probiotic treatment for gastrointestinal
> disorders.
>
> Probiotics, preparations containing beneficial bacteria,
> have already been used to treat conditions such as
> ulcerative colitis and
pouchitis.
>
> "The use of probiotics has had some success, but their use
> is made difficult by the fact that the bugs tend not to
> persist in the gut,
and
> treatments have to be given week after week," Dr
> Forbes said.
>
> "If there was some way of modifying bacteria so they could
> continue
to
> infect the gut, but remain safe, that would be useful."
>
> Dr Forbes said scientists were also working on prebiotic
> treatments, which provide nutrients to encourage the growth
> of certain bacteria.
>
> However, he said knowledge about the bacteria which live
> in the gut
was
> still relatively limited.
>
> It is estimated that only about 20-30% of the bacteria
> that inhibit
the
> gut have been identified.

[Dr_dickie]

"Robert" <RobertJ@hotmail.com> wrote in message
news:PNmdnTgUzuRuTqLfRVn-tg@got.net...
>
> "montygram" <nazztrader@lycos.com> wrote in message news:11-
> 11468838.750904.74560@o13g2000cwo.googlegroups.com...
> > No question one wants the "good bacteria" in the gut, but
> > this report makes it seem like any bacterium or virus is
> > going to get slammed by the "immune system." In reality,
> > there are more bacteria cells than human cells in the
> > human body. In mice, and probably mammals in general,
> > there are hundreds (if not thousands) of different kinds
> > of one class of virus (retroviruses). The key question is
> > how do various things prompt an "autoimmune resposnse,"
> > and here the evidence points to arachidonic acid excess,
> > which is why the usual crowd is hawking
>
> Learn how to read please. It does not mention "autoimmune".
> It mentions an immune response that is lacking against
> bacteria present in the gut.
>
> > fish oil - it interferes with arachidonic acid metabolism
> > (though not without charging a very high price - lipid
> > peroxidation). Instead, if you avoid more than trace
> > amounts of polyunsaturated fatty acids, you probably won't
> > have to worry about any of this kind of thing.
> >
> What in the world are you talking about? Where is AA or
> polyunsaturated
fats
> mentioned in this article? Get a grip on yourself man. You
> sound like a broken record.
>

Yeah, come'on, everyone know that Al Qaeda is behind this
whole arachadonic acid thing ;-0 EVERY FREAKIN' SINGLE problem
in the world is caused by lipid peroxidation, according to
monty. When all you have is a hammer, everything starts
looking like a nail.

--
Dr. Dickie Skepticult member in good standing #394-00596-438
Poking kooks with a pointy stick. "The most exciting
phrase to hear in science, the one that heralds new
discoveries, is not 'Eureka!' ('I found it!'), but rather
'hmm....that's funny...'"
- Isaac Asimov

[Montygram]

What I stated is relevant to the subject of health, whereas
they simply restated the obvious. They have been telling us
that a cure for cancer would be had by 1980, that an AIDS
vaccine would be available around 1985, etc. Now they are
saying people are going to begin to die sooner, and that an
Alzheimer's epidemic is on the horizon. I am explaining how to
avoid those things. If they knew what role AA metabolites,
lipid peroxidation, etc. play in various "pathologies" I would
never have to post here. You may be an ignoramus, but I'm
writing this for those who are not.

[Robert]

"montygram" <nazztrader@lycos.com> wrote in message
news:1111551658.864325.121440@f14g2000cwb.googlegroups.com...
> What I stated is relevant to the subject of health, whereas
> they simply restated the obvious. They have been telling us
> that a cure for cancer would be had by 1980, that an AIDS
> vaccine would be available around 1985, etc. Now they are
> saying people are going to begin to die sooner, and that an
> Alzheimer's epidemic is on the horizon.
Those were all funding ploys in the hope that it actually
might happen.

I am
> explaining how to avoid those things. If they knew what role
> AA metabolites, lipid peroxidation, etc. play in various
> "pathologies" I would never have to post here. You may be an
> ignoramus, but I'm writing this for those who are not.

Try taking a basic course on pathology. Oxidative stress is
present everywhere, in every tissue and cell in the human
body. Oxygen is essential for life and the electron transport
creats highly reactive free radial oxygen groups. You don't
need to eat anything oxidized to have that happen. Cells that
are damaged by whatever mechanism you can think of can not
withstand the oxidative stress and will eventually succumb to
it and die. It is one of the last stages of cell death. You
can name any and all diseases known to man to be involved with
cellular damage and death to be connected to lipid
peroxidation. The bodies own immune defense against
microorganism uses oxidative stress directed against the
organisms. If you can come up with specific intervental
treatments that have proven to work on any of those topics
then fine. I know a few but then they are few and far between.
I don't have any problems you telling people to cut out all
the oxidized butter with a knife or to eat coconuts for the
next twenty years.