Team:UC Davis/Project

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style="font-size: 13.5pt; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;"><big><big><big><big><a
style="font-size: 13.5pt; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;"><big><big><big><big><a
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href="https://2009.igem.org/Team:UC_Davis/homepage2"><img alt=""
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src="https://static.igem.org/mediawiki/2009/a/a4/UCDAVIS_PIC3.png"
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style="border: 0px solid ; width: 83px; height: 36px;"></a> </big></big></big></big></span></b><a
style="border: 0px solid ; width: 83px; height: 36px;"></a> </big></big></big></big></span></b><a
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href="https://2009.igem.org/Team:UC_Davis/About_Us1"><b
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href="https://2009.igem.org/Team:UC_Davis/About_Us"><b
style="color: rgb(255, 255, 153);"><span
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style="border: 0px solid ; width: 78px; height: 36px;"></a> </big></big></big></big></span></b><b
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style="border: 0px solid ; width: 78px; height: 37px;"></a>&nbsp;<a
style="border: 0px solid ; width: 78px; height: 37px;"></a>&nbsp;<a
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style="color: rgb(0, 0, 0);"> </b>
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<hr style="width: 100%; height: 2px;">
<hr style="width: 100%; height: 2px;">
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<div style="text-align: left;"><b style="color: rgb(0, 0, 0);"><big><big>Project:</big></big><br>
+
<div style="text-align: left;"><b style="color: rgb(0, 0, 0);"><big
 +
style="text-decoration: underline;"><big>Project:</big></big><br>
</b>
</b>
<div style="text-align: center;"><b style="color: rgb(0, 0, 0);"><a
<div style="text-align: center;"><b style="color: rgb(0, 0, 0);"><a
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<small><u><span
<small><u><span
style="font-size: 20pt; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;"><span
style="font-size: 20pt; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;"><span
-
style="font-weight: bold;"><a name="celiac_disease"></a>Celiac Disease:</span><br>
+
style="font-weight: bold;"><a name="celiac_disease"></a></span></span></u></small><span
-
</span></u></small><i style="font-weight: bold;"><span
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style=""><big><big style="text-decoration: underline;"><span
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style="font-size: 14pt; line-height: 115%; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;"><br>
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style="font-weight: bold;">What is Celiac Disease?</span></big></big><o:p></o:p></span>
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</span></i><i><span
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<p>&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; Celiac Disease is an
-
style="font-size: 14pt; line-height: 115%; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;">What
+
autoimmune
-
is Celiac Disease?</span></i><br>
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disorder that occurs inside the small
-
<i><u><span
+
intestine. When the body cannot properly digest gliadin (a component of
-
style="font-size: 20pt; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;"></span></u></i><span
+
gluten),
-
style="font-size: 12pt; line-height: 115%; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;">&nbsp;&nbsp;&nbsp;
+
this leads to an immune response on the surface of the small intestine
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&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; Celiac
+
(14).
-
Disease is a form of autoimmune disorder, which occurs inside the small
+
Different people have varying degrees of immune
-
intestine. When the body cannot digest gliadin (component of gluten)
+
response
-
properly,
+
such as bloating, diarrhea, and weight loss (14). An estimated one out
-
this leads to an immune response (14). Furthermore, different people
+
of 133 Americans currently suffer from this
-
have
+
disease (11). Considering the estimated 3.08 million people in America,
-
different reactions to these immune responds such as pain and vomiting
+
this isn't a minor issue. In fact, it was one of our teammate's friends
-
(14). It
+
suffering from celiac who initially sparked our interest in designing
-
has been estimated that about one out of 133 Americans are currently
+
this project. <o:p></o:p><span style=""><small><span
-
suffering
+
style="font-style: italic;"><br>
-
from this disease (11); including one of our teammate's friends, and
+
</span></small></span></p>
-
that was
+
<p><span style=""><big style="font-weight: bold;"><span
-
what sparked our interest in designing this project.</span><span
+
style="font-style: italic;">What happens in the normal small
-
style="font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;"><span style="">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
+
intestine?</span></big><o:p></o:p></span><span
-
</span></span><span
+
style="font-weight: bold;"></span><br>
-
style="font-size: 14pt; line-height: 115%; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;"><span
+
&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; <br>
-
style=""></span><span style=""></span></span><span
+
&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; The inside surface of the small
-
style="font-style: italic;"><span
+
intestine is covered with small microvilli, constituting the brush
-
style="font-size: 14pt; line-height: 115%; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;"><br>
+
border membrane. In the normal small intestine, the brush border
-
<br>
+
membrane is where polysaccharides, proteins, and fat droplets are
-
What happens in the normal small
+
digested into smaller parts that then get absorbed into the
-
intestine?</span></span><span
+
bloodstream. <br>
-
style="font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;"><o:p></o:p></span><span
+
</p>
-
style="font-size: 12pt; line-height: 115%; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;"><br>
+
<p><o:p></o:p><span style=""><big><span
-
&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; In
+
style="font-weight: bold; font-style: italic;">What happens in the
-
the normal small intestine, the Brush border membrane lets small
+
small intestine of people with celiac
-
peptides and
+
disease?</span></big><o:p></o:p></span></p>
-
molecules like water through and into the bloodstream. The brush border
+
<span style="font-weight: bold;"></span>
-
membrane also lets larger molecules into the blood stream, similar to
+
<p>&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; The brush border
-
Gliadin;
+
characteristic to people with celiac disease allows large molecules
-
however, these larger molecules are converted through a transcellular
+
such as gliadin to go straight
-
route, which
+
into the
-
does not prompt an immune system response.<o:p></o:p></span><i><span
+
blood stream without directing them through the transcellular route.
-
style="font-size: 14pt; line-height: 115%; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;"><br>
+
Once
-
<br>
+
gliadin passes through, Antigen Presenting Cells (APCs) recognize
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What
+
gliadin as a
-
happens in celiac disease small intestine?</span></i><i><span
+
foreign object and attack. This immune response results in the
-
style="font-size: 14pt; line-height: 115%; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;"><span
+
inflammation of
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style="">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
+
the surface of the intestine with loss of the normal cells required for
-
</span><o:p></o:p></span></i><span
+
absorption of sugars, protein, and fat from the diet. <o:p></o:p></p>
-
style="font-size: 12pt; line-height: 115%; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;"><br>
+
<p>&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; In addition to the array of
-
&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; The
+
symptoms illustrated above, the immune response may also damage
-
Brush border membrane in the small intestine of people suffering from
+
intestinal villi, which are important
-
Celiac Disease
+
for
-
allows large molecules such as gliadin to go straight into the blood
+
absorbing nutrients. The destruction of villi eventually leads to a
-
stream
+
lack of
-
without directing them through the transcellular route. Once gliadin
+
absorption of different nutrients, which can lead to malnutrition (14).
-
passes
+
Some
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through, Antigen Presenting Cells (APCs) recognize gliadin as a foreign
+
people affected with this disorder can also suffer from autoimmune
-
object
+
thyroid
-
and will attack. This immune response causes pain and other adverse
+
disease, autoimmune liver disease, and rheumatoid arthritis (diseases
-
side-effects.<o:p></o:p></span>
+
in
-
<p class="MsoNormal" style="text-indent: 0.5in;"><span
+
which body immune system attacks healthy cells/tissues) (14). <o:p></o:p></p>
-
style="font-size: 12pt; line-height: 115%; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;">The
+
-
immune response not only causes abdominal bloating, pain, weight loss
+
-
and
+
-
vomiting, most of the time it may also damage intestinal villi, which
+
-
are
+
-
important for absorbing nutrition. The destruction of villi eventually
+
-
leads to
+
-
a lack of absorption of different nutrients, which can lead to other
+
-
illnesses
+
-
(14). Some people affected with this disorder can also suffer from </span><span
+
-
style="font-size: 12pt; line-height: 115%; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;">autoimmune
+
-
thyroid disease, autoimmune liver disease, rheumatoid arthritis </span><i><span
+
-
style="font-size: 12pt; line-height: 115%; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;">(diseases
+
-
in which body immune system attacks healthy cells/tissues)</span></i><span
+
-
style="font-size: 12pt; line-height: 115%; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;">
+
-
(14).</span><b><span
+
-
style="font-size: 12pt; line-height: 115%; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;"><br>
+
-
</span></b></p>
+
<hr style="width: 100%; height: 2px;">
<hr style="width: 100%; height: 2px;">
-
<p class="MsoListParagraph" style=""><u><span
+
<p><u><span
style="font-size: 12pt; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;"><big><big><span
style="font-size: 12pt; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;"><big><big><span
style="font-weight: bold;"><a name="current_treatment"></a>Current
style="font-weight: bold;"><a name="current_treatment"></a>Current
-
treatments:</span></big></big><o:p></o:p></span></u></p>
+
treatments:</span></big></big><o:p></o:p></span></u><br>
-
<p class="MsoNormal" style="line-height: normal;"><b><span
+
<b><span
-
style="font-size: 12pt; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
+
style="font-size: 12pt; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;"></span></b><span
-
</span></b><span
+
style="font-size: 12pt; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;"></span><br>
-
style="font-size: 12pt; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;">Currently,
+
&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; Currently, no cure has been found
-
no cure has been found
+
for this illness. The only way to avoid
-
for this illness. The only way to avoid some of celiac disease’s
+
the symptoms of celiac disease is by adopting a gluten-free diet
-
symptoms is by
+
(14, 12,
-
adopting a gluten free diet (14, 12, and 11). However, you are more
+
and 11). However, you are highly likely to find gluten in your everyday
-
likely to
+
diet (in foods such as grains), and
-
find gluten in your everyday diet. Therefore, avoiding gluten is not
+
people with celiac disease must purchase gluten-free substances from
-
easy or
+
specialized grocery stores. "Oral supplementation with prolyl
-
pleasant from a gastronomical standpoint.<br>
+
oligopeptidases that can digest and detoxify gluten has therefore been
-
</span><span
+
-
style="font-size: 12pt; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;"><o:p></o:p>
+
-
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp;
+
-
"Oral supplementation with prolyl oligopeptidases has therefore been
+
proposed
proposed
-
as a potential therapeutic approach."(8). However, enzymes studied
+
as a potential therapeutic approach."(8) However, enzymes studied
earlier
earlier
-
were not able to degrade gluten (inside stomach before it reaches small
+
were not able to degrade gluten inside the stomach (before it reaches
-
intestine because they were "irreversibly inactivated by pepsin and
+
the small
-
acidic
+
intestine), because they were "irreversibly inactivated by pepsin and
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pH, both present in the stomach."(8)<o:p></o:p></span><span
+
acidic pH, both present in the stomach."(8) <o:p></o:p></p>
-
style="font-size: 12pt; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;"><br>
+
<p>&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; Nevertheless, over the past
-
&nbsp; &nbsp; &nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;
+
years, researchers have discovered an enzyme--a newly-identified prolyl
-
Nevertheless, over the past years, researchers have discovered an
+
endoprotease--from <i>Aspergillus niger</i>, that was
-
enzyme from <i>Aspergillus
+
observed to "work optimally at 4-5pH and remains stable at 2pH"(8).
-
niger</i>, a newly identified prolyl endoprotease, that was observed to
+
Perhaps this enzyme will lead us to an alternative treatment for this
-
"work optimally at 4-5pH and remains stable at 2pH"(8) and maybe this
+
disorder(8). Studies have shown that prolyl endoprotease from <i>A.niger</i>
-
enzyme will lead us to an alternative treatment for this disorder (8).
+
is able to "degrade gluten in vitro and under conditions
-
Studies
+
similar
-
have shown that prolyl-endoprotease from <i>Aspergillus niger</i> is
+
to the ones present in the gastrointestinal tract." (8)&nbsp;; However,
-
able to
+
due
-
"degrade gluten in vitro and under conditions similar to the ones
+
to
-
present
+
licensing restrictions, we have opted not to work with this protein. <o:p></o:p></p>
-
in the gastrointestinal tract." (8) ; but due to licensing restrictions
+
<p>&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; Recently (year 2007), a study
-
we
+
has suggested an alternative approach by
-
have opted not to work with this protein.</span><span
+
-
style="font-size: 12pt; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;"><o:p></o:p></span><br>
+
-
<span style="font-size: 12pt; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
+
-
Recently (year 2007), a study has suggested an alternative approach by
+
combining a glutamine-specific endoprotease (EP-B2 from barley) and a
combining a glutamine-specific endoprotease (EP-B2 from barley) and a
prolyl
prolyl
-
endopeptidase (SC PEP from Sphingomonas capsulata); with gastric
+
endopeptidase (SC PEP from <span style="font-style: italic;">Sphingomonas
 +
capsulata</span>) with gastric
activity and
activity and
-
complementary substrate specificity there is a possibility of
+
complementary substrate specificity(12). Using this method, there is a
 +
possibility of
increasing the
increasing the
-
safe threshold of ingested gluten (12). One of the advantages of this
+
safe threshold of ingested gluten(12). One of the advantages of this
“combination product is that both enzymes are active and stable in
“combination product is that both enzymes are active and stable in
stomach and
stomach and
can therefore be administered as lyophilized powders or simple capsules
can therefore be administered as lyophilized powders or simple capsules
or
or
-
tablets” (12).</span><span
+
tablets”(12). <o:p></o:p><br>
-
style="font-size: 12pt; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;"><o:p></o:p></span></p>
+
<o:p></o:p></p>
<p class="MsoNormal" style="line-height: normal;"><i><span
<p class="MsoNormal" style="line-height: normal;"><i><span
-
style="font-size: 12pt; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;">Note:
+
style="font-size: 12pt; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;"></span></i><span
-
Moreover, this study was first
+
-
“evaluated via in vitro digestion of whole-wheat beard and then
+
-
confirmed by in
+
-
vivo studies in rats (12), unlike other earlier studies which were
+
-
performed on
+
-
synthetic gluten oligopeptides, recombinant gliadin proteins, or
+
-
uncooked
+
-
gluten” (12).</span></i><span
+
style="font-size: 12pt; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;"><o:p></o:p></span></p>
style="font-size: 12pt; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;"><o:p></o:p></span></p>
<hr style="width: 100%; height: 2px;"><b><u><span
<hr style="width: 100%; height: 2px;"><b><u><span
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name="our_approach"></a>Our
name="our_approach"></a>Our
approach:<o:p></o:p></span></u></b>
approach:<o:p></o:p></span></u></b>
-
<p class="MsoNormal"><span
+
<p>&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; Gliadin induces an immune
-
style="font-size: 16pt; line-height: 115%; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;"><span
+
system response when it is absorbed into
-
style="">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span></span><span
+
the blood stream through the small intestine. We plan to take advantage
-
style="font-size: 12pt; line-height: 115%; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;">We
+
of this by breaking down gliadin in the stomach before it reaches the
-
are going to break down gluten inside the stomach (before it arrives to
+
small intestine. We have developed a secretion system to release an
-
the
+
enzyme that can break down gliadin. Also, in order to prevent our
-
small intestine), because gliadin does not prompt an immune system
+
delivery system from taking residence anywhere outside of the stomach,
-
response until
+
we plan to incorporate the difference in pH between the stomach and
-
it is absorbed in the small intestine.<span style="">&nbsp;
+
small intestine with a pH-inducible apoptosis system. By adopting these
-
</span>Another worry is a spread of our synthetic bug, so we engineered
+
two systems, we will create a pH-moderated secretion system.<br>
-
a
+
&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; Unlike other suggested treatments
-
‘safety-switch’ via induction of cell death through a pH sensor system.<span
+
requiring the consumption of capsules or tablets, our method of using <i>E.
-
style="">&nbsp; </span>Due to the change of pH from the stomach to
+
coli</i> as our delivery system is more cost- and time-efficient.
-
the small intestine, our pH system is induced; cell death, thus
+
</p>
-
limiting our
+
-
bug to the stomach.<o:p></o:p></span></p>
+
-
<p class="MsoNormal"><span
+
-
style="font-size: 12pt; line-height: 115%; font-family: &quot;Times New Roman&quot;,&quot;serif&quot;;"><span
+
-
style="">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
+
-
</span>The
+
-
advantages of our model are, that unlike other suggested treatments
+
-
which
+
-
require consuming capsules or tablets rapidly, by using <i><span
+
-
style="color: black;">Escherichia coli</span></i><span
+
-
style="color: black;"> as
+
-
our model chassis for this project: we can lower the number of times
+
-
which this
+
-
‘cure’ needs to be consumed thus making it less troublesome, costly,
+
-
and more
+
-
convenient.<br>
+
-
</span></span></p>
+
<hr style="width: 100%; height: 2px;">
<hr style="width: 100%; height: 2px;">
<p class="MsoNormal"><span style="font-weight: bold;">Our project is
<p class="MsoNormal"><span style="font-weight: bold;">Our project is
split into two parts:</span><br>
split into two parts:</span><br>
-
1.Induced Secretion<br>
+
1. Induced Secretion<br>
</p>
</p>
<ul>
<ul>
-
<li><a
+
<li><a href="https://2009.igem.org/Team:UC_Davis/Adding_secretion">Adding
 +
secretion</a><span style="text-decoration: underline;"></span></li>
 +
<li><span style="text-decoration: underline;"></span><a
href="https://2009.igem.org/Team:UC_Davis/Gene_sequence_for_secretion_system">Gene
href="https://2009.igem.org/Team:UC_Davis/Gene_sequence_for_secretion_system">Gene
-
sequence for secretion system</a>
+
sequence for secretion system</a><span
-
</li>
+
style="text-decoration: underline;"></span></li>
-
<li><a href="https://2009.igem.org/Team:UC_Davis/Adding_secretion">Adding
+
<li><span style="text-decoration: underline;"></span><a
-
secretion</a>
+
-
</li>
+
-
<li><a
+
href="https://2009.igem.org/Team:UC_Davis/assay_for_measuring_protein_localization_and_activity">Assay
href="https://2009.igem.org/Team:UC_Davis/assay_for_measuring_protein_localization_and_activity">Assay
for measuring protein localization and activity</a></li>
for measuring protein localization and activity</a></li>
</ul>
</ul>
-
2.Sensing pH&nbsp; and inducing cell death<br>
+
<ul>
 +
</ul>
 +
2. Sensing pH&nbsp; and inducing cell death<br>
<ul>
<ul>
<li><a
<li><a
Line 272: Line 225:
<li><a href="https://2009.igem.org/Team:UC_Davis/wiring_pH_sensor">Wiring
<li><a href="https://2009.igem.org/Team:UC_Davis/wiring_pH_sensor">Wiring
the pH sensor into our system</a>
the pH sensor into our system</a>
-
</li>
 
-
<li><a href="https://2009.igem.org/Team:UC_Davis/assay_for_pH_sensor">Assay
 
-
for measuring the behavior of the pH sensor</a>
 
</li>
</li>
</ul>
</ul>

Latest revision as of 02:30, 22 October 2009

lol

   
Project:
Celiac Disease          Current treatment           Our Approach
What is Celiac Disease?

        Celiac Disease is an autoimmune disorder that occurs inside the small intestine. When the body cannot properly digest gliadin (a component of gluten), this leads to an immune response on the surface of the small intestine (14). Different people have varying degrees of immune response such as bloating, diarrhea, and weight loss (14). An estimated one out of 133 Americans currently suffer from this disease (11). Considering the estimated 3.08 million people in America, this isn't a minor issue. In fact, it was one of our teammate's friends suffering from celiac who initially sparked our interest in designing this project.

What happens in the normal small intestine?
       
        The inside surface of the small intestine is covered with small microvilli, constituting the brush border membrane. In the normal small intestine, the brush border membrane is where polysaccharides, proteins, and fat droplets are digested into smaller parts that then get absorbed into the bloodstream.

What happens in the small intestine of people with celiac disease?

        The brush border characteristic to people with celiac disease allows large molecules such as gliadin to go straight into the blood stream without directing them through the transcellular route. Once gliadin passes through, Antigen Presenting Cells (APCs) recognize gliadin as a foreign object and attack. This immune response results in the inflammation of the surface of the intestine with loss of the normal cells required for absorption of sugars, protein, and fat from the diet.

        In addition to the array of symptoms illustrated above, the immune response may also damage intestinal villi, which are important for absorbing nutrients. The destruction of villi eventually leads to a lack of absorption of different nutrients, which can lead to malnutrition (14). Some people affected with this disorder can also suffer from autoimmune thyroid disease, autoimmune liver disease, and rheumatoid arthritis (diseases in which body immune system attacks healthy cells/tissues) (14).


Current treatments:

        Currently, no cure has been found for this illness. The only way to avoid the symptoms of celiac disease is by adopting a gluten-free diet (14, 12, and 11). However, you are highly likely to find gluten in your everyday diet (in foods such as grains), and people with celiac disease must purchase gluten-free substances from specialized grocery stores. "Oral supplementation with prolyl oligopeptidases that can digest and detoxify gluten has therefore been proposed as a potential therapeutic approach."(8) However, enzymes studied earlier were not able to degrade gluten inside the stomach (before it reaches the small intestine), because they were "irreversibly inactivated by pepsin and acidic pH, both present in the stomach."(8)

        Nevertheless, over the past years, researchers have discovered an enzyme--a newly-identified prolyl endoprotease--from Aspergillus niger, that was observed to "work optimally at 4-5pH and remains stable at 2pH"(8). Perhaps this enzyme will lead us to an alternative treatment for this disorder(8). Studies have shown that prolyl endoprotease from A.niger is able to "degrade gluten in vitro and under conditions similar to the ones present in the gastrointestinal tract." (8) ; However, due to licensing restrictions, we have opted not to work with this protein.

        Recently (year 2007), a study has suggested an alternative approach by combining a glutamine-specific endoprotease (EP-B2 from barley) and a prolyl endopeptidase (SC PEP from Sphingomonas capsulata) with gastric activity and complementary substrate specificity(12). Using this method, there is a possibility of increasing the safe threshold of ingested gluten(12). One of the advantages of this “combination product is that both enzymes are active and stable in stomach and can therefore be administered as lyophilized powders or simple capsules or tablets”(12).


Our approach:

        Gliadin induces an immune system response when it is absorbed into the blood stream through the small intestine. We plan to take advantage of this by breaking down gliadin in the stomach before it reaches the small intestine. We have developed a secretion system to release an enzyme that can break down gliadin. Also, in order to prevent our delivery system from taking residence anywhere outside of the stomach, we plan to incorporate the difference in pH between the stomach and small intestine with a pH-inducible apoptosis system. By adopting these two systems, we will create a pH-moderated secretion system.
        Unlike other suggested treatments requiring the consumption of capsules or tablets, our method of using E. coli as our delivery system is more cost- and time-efficient.


Our project is split into two parts:
1. Induced Secretion

2. Sensing pH  and inducing cell death