Difference between revisions of "Team:Freiburg/Project/Future Directions"

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<h1 class="sectionedit1">Future Direction</h1>
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Der folgnde Absatz liest sich sehr holperig. es wäre schön, wenn man da nochmal drüber gehen könnte und ein bisschen präziser formulieren würde. Prinzipiell nochmal hervorheben, dass es darum geht vor ort die Tests durchzuführen (vll noch in die ecke Ärzte ohne Grenzen bringen, von wegen schnellen test in Krisengebieten. <br>
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  // CHANGE THE FOLLOWING ATTRIBUTES //
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Hab mal dran gebastelt -> bitte korrigieren! (jb 20150909)
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The detection of antibodies in a blood sample is a versatile and widely applied method of today's diagnostics 1) 2). Common methods include ELISA-assays which rely on the immobilization of antigens beforehand, requiring stable conditions for handling and storage of the plates as test reliability is crucially dependent on native-state proteins. Maintaining these conditions is already quite expensive under European standards, but becomes elaborate when working in tropical or arid regions.
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Especially in those regions, where hospitals are mostly hard to reach and local medical treatment seldom relies on physicians, it is necessary to reliably distinguish between different illnesses as fast and accurate as possible. The treatment of potential epidemic pathogens requires an enormous logistic effort and differential diagnosis of a less potent pathogen may save thousands of dollars and prevent fear among people. Thus, it would be beneficial to have a large library of known antigens that is easy and cost-effective to store and to ship, but nonetheless functions as a reliable selective tool in diagnostics.
+
−
</br>
+
−
Our idea of how to tackle this problem is to use the unique properties of DNA as a robust information storage and combine it with cell-free expression inside a detection device. The antigens, produced on-demand directly before diagnosis, are not only less prone to denaturation, but are also enriched on the array in the device by a specific surface. Antibodies potentially present in the patient's blood are then observed by a new kind of detection method called iRIf. The associated measuring device can be scaled down to a size as small as a laptop computer.
+
−
</br>
+
−
This portability makes the DiaCHIP useful for mobile applications especially in third world countries or regions of conflict where treatment decisions have to be made fast and on-site. The potentially low costs of the device render it affordable for organisations with trained personal such as "Medicines sans frontiers", replacing lots of bulky equipment and making it easier to get access to remote areas.
+
  
 +
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<div class="content_box">
 +
 +
<h1>Future Directions</h1>
 +
 +
<h2>Room for Improvement</h2>
 +
<div class="floatbox left">
 +
<p>
 +
The detection of antibodies in a blood sample is a versatile and widely applied method of today's diagnostics. Common methods include ELISA, an immunodiagnostic method based on the interaction of antibodies and corresponding antigens. As test reliability is crucially dependent on native-state proteins <sup><a class="fn_top" href="#fn__1" id="fnt__1" name="fnt__1">1)</a></sup>, ELISA plates require stable conditions for handling and storage. Maintaining these conditions is already quite expensive under European standards but becomes elaborate when working in tropical or arid regions.
 +
<br>
 +
Especially in regions, where hospitals are hard to reach and local medical treatment seldom relies on
 
</p>
 
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<a class="media" href="https://static.igem.org/mediawiki/2015/f/f0/Freiburg_wiki-logo.png" title="wiki:logo.png"><img alt="" class="mediacenter" src="https://static.igem.org/mediawiki/2015/f/f0/Freiburg_wiki-logo.png" width="500"/></a>
 
 
</div>
 
</div>
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 +
<div class="floatbox right">
 
<p>
 
<p>
 +
physicians, it is necessary to reliably distinguish different illnesses as fast and accurate as possible. The treatment of potential epidemic pathogens requires an enormous logistic effort and differential diagnosis of a less potent pathogen may save thousands of dollars and prevent fear among people. Thus, it would be beneficial to have a large library of known antigens that is easy and cost-effective to store and to ship and is additionally functional as a reliable and selective tool in diagnostics.
 +
</p>
 +
</div>
  
−
Our project keeps many possible applications at hand if we will be able to further optimize the cell-free expression system and the specific binding to the surface for generating a protein chip. Improving the device towards a more quantitative method may allow medical professionals to determine the state of vaccination of a patient for a whole set of antigens, thus rendering some additional immunizations unnecessary.
+
<br style="clear:both">
  
−
</p>
+
<h2>The DiaCHIP - On the Way Towards Future Diagnostics</h2>
−
<div class="image_box right"
+
 
−
<a class="media" href="https://static.igem.org/mediawiki/2015/c/cd/Freiburg_labjournal-cloning-150831_vaccination_rj.png" title="labjournal:cloning:150831_vaccination_rj.png"><img align="right" alt="" class="mediaright" src="https://static.igem.org/mediawiki/2015/c/cd/Freiburg_labjournal-cloning-150831_vaccination_rj.png" width="200"/></a>
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 +
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</div>
 
</div>
 +
 
<p>
 
<p>
−
The DiaCHIP could provide a tool for accurate analysis of the antibody titer of a person, thus helping to keep up a constant protection against many diseases.  
+
Our idea of how to tackle this problem is to use the unique properties of DNA as a <b>robust information storage</b> and combine it with cell-free expression inside a microfluidic device. At the same time, this device is used for detection of antibodies in a label-free manner. The antigens produced on demand directly before diagnosis are not only less prone to time-related denaturation but also enriched on the array due to a specific surface. Antibodies potentially present in the patient's blood are then observed by a new kind of detection method called iRIf (imaging Reflectometric Interference). The associated measurement device can be scaled down to a size smaller than a shoebox and a price affordable for almost everybody.
 +
</br>
 +
This <b>portability</b> makes the DiaCHIP useful for mobile applications especially in third world countries or regions of conflict where decisions for the appropriate treatment have to be taken fast and on-site. The potentially low costs of the device render it <b>affordable</b> for organisations with trained personnel such as <a class="urlextern" href="http://www.doctorswithoutborders.org/" target="_blank" title="MSF">Doctors Without Borders</a>, replacing lots of bulky equipment and making it easier to operate in solitary areas.
 +
</p>
  
−
As the iRIf technology only detects binding on the surface it is not possible to directly differentiate between existing antibodies due to an infection in the past or fresh antibodies resulting from an acute infection or from vaccination. A possible approach for dealing with this issue is the labeling of bound antibodies with proteins specific for one type of antibody, past infection related IgG or vaccination related IgM. Protein A may be such a candidate as it specifically binds to IgG but not to IgM. Additionally conventional secondary antibodies against both of these types may be used to cross-validate the results and thereby adding an additional layer of reliablility to the test.
+
<p>
 +
Our project keeps many possible applications at hand if we will be able to further optimize the cell-free expression system and the specific binding to the surface for generating a protein array.  
 +
</p>
  
−
</br>
 
−
</br>
 
  
−
With further work on the DiaCHIP it could also be possible to distinguish between vaccines from different manufactures by spotting different epitopes of one antigen on the slide. This offers the opportunity to determine, whether the patient is vaccinated against a certain type of a virus. For expample the Human Papilloma Virus (HPV) shows several subtypes (as HPV-16 and HPV-18 or HPV-11 and HPV-6) differing in the characteristics of the disease. Knowing the vaccination status of a patient for these different subtypes could help to asses the personal risks for several diseases <sup><a class="fn_top" href="#fn__1" id="fnt__1" name="fnt__1">1)</a></sup> .
+
<h2>Determining the Status of Vaccination</h2>
−
</br>
+
−
</br>
+
−
The DiaChip could also be used for pre-pregnancy test, where evaluation of the antibody titers against certain diseases like e.g. rubella or whooping cough is crucial. Here the safety of the unborn child relies on the health status of the mother, therefore missing vaccinations should be detected before considering a pregnancy. With our chip this may be a matter of one drop of blood and a test of two to three hours including the expression of antigens on the slide.
+
  
−
In the same way blood samples from blood banks or blood donations can be checked. And as the volume needed is very small checks can be performed in short-time intervals and nearly continuous monitoring of blood-quality may be possible.
+
<div class="image_box right">
 +
  <img align="right" alt="" src="https://static.igem.org/mediawiki/2015/2/2f/Freiburg_vaccination_syringe.png" width="200">
 +
</div>
 +
 
 +
<p>
 +
Improving the device in terms of quantification may allow medical professionals to determine a patient's status of vaccination for a whole set of pathogens, thus possibly rendering some vaccination boosts unnecessary.  
 +
The DiaCHIP could provide a tool for accurate analysis of the antibody titer of a person, thereby helping to keep up a constant protection against many diseases.
 +
<br>
 +
With the iRIf technology antibody-antigen interactions are detected. Nonetheless, there is no possibility of differentiating between antibodies that were already present due to a previous infection or vaccination, or ones that were developed due to an acute infection. A possible approach for dealing with this issue is the labeling of bound antibodies with proteins that bind specifically to one class of antibodies. Antibodies resulting form a previous infection or vaccination belong to the IgG class, those of an acute infection to the IgM class. Protein A may be a candidate for this purpose as it specifically binds to IgG but not to IgM. Additionally, conventional secondary antibodies targeting different classes of human antibodies may be used to cross-validate the results and thereby add an additional layer of reliablility to the test.
 
</p>
 
</p>
 +
 +
<p>
 +
Investing further work on the DiaCHIP could make it possible to distinguish between vaccines from different manufactures by spotting different epitopes of one antigen on the slide. This offers the opportunity to determine whether the patient is vaccinated against a certain subtype of a virus. For example, the Human Papilloma Virus (HPV) shows several subtypes (such as HPV-6, HPV-11, HPV-16 or HPV-18) differing in the characteristics of the disease. Knowing the vaccination status of a patient for these different subtypes could help to asses the personal risks for several diseases <sup><a class="fn_top" href="#fn__2" id="fnt__2" name="fnt__2">2)</a></sup> .
 +
</p>
 +
 +
 +
<h2>Pre-Pregnancy Testing</h2>
 +
<p>
 +
The DiaCHIP could additionally be used for pre-pregnancy testing where the evaluation of vaccination statuses for a whole set of diseases like rubella or whooping cough is crucial. In this case, the safety of the unborn child relies on the health status of the mother. Therefore, a lack of vaccination should be detected when a pregnancy is considered. With our DiaCHIP this may be a matter of one drop of blood and only one test, requiring a maximum of two to three hours including the expression of antigens on the slide.
 +
</p>
 +
 +
 +
<h2>Blood Sample Analysis</h2>
  
 
<div class="image_box left">
 
<div class="image_box left">
−
<a class="media" href="https://static.igem.org/mediawiki/2015/4/43/Freiburg_labjournal-cloning-banked_blood.png" title="labjournal:cloning:banked_blood.png"><img align="right" alt="" class="mediaright" src="https://static.igem.org/mediawiki/2015/4/43/Freiburg_labjournal-cloning-banked_blood.png" width="200"/></a>
+
<a class="media" href="https://static.igem.org/mediawiki/2015/4/43/Freiburg_labjournal-cloning-banked_blood.png" title="labjournal:cloning:banked_blood.png"><img align="right" alt="" class="mediaright" src="https://static.igem.org/mediawiki/2015/4/43/Freiburg_labjournal-cloning-banked_blood.png" width="80"/></a>
 
</div>
 
</div>
  
 
<p>
 
<p>
−
Beyond fields of application in clinics as such, the suggested method of cell-free expression would simplify the preparation of protein microarrays on demand as no purification of protein is necessary anymore. This could be a major advantage in scientific research as handling and storage of protein arrays still poses some challenges. With our system of cell-free expression the production of protein arrays could provide an easy method to work with freshly produced protein chips.
+
Blood samples from blood banks or blood donations can be checked for multiple infectious diseases in the same way. Since the required volume is very small, checks can be performed in short-time intervals and continuous monitoring of blood-quality may be possible.
−
As cDNA libraries are a common tool in basic research this can be easily combined with our system of cell-free expression and immobilization of proteins on a glass slide. With this set-up screenings for potential interacting proteins can be facilitated and improved through multiplexing applications.
+
<br>
−
</br>
+
Furthermore, one could develop a pre-test for critical diseases before donating blood. Like this, donations of infected blood could be prevented from the beginning.
−
</br>
+
−
In our iGEM project we were able to detect two diseases (Tetanus and Salmonella), but these are just two out of 1000 diseases our DiaCHIP will hold.
+
−
</div>
+
 
</p>
 
</p>
−
<div class="tags"><span>
+
 
−
<a class="wikilink1" href="/igem2015/doku.php?id=tag:info&amp;do=showtag&amp;tag=info" rel="tag" title="tag:info">info</a>
+
 
−
</span></div>
+
<h2>Providing Access to Fresh Protein Arrays for Laboratory Use</h2>
 +
<p>
 +
Beyond applications in the field of clinics as such, the suggested method of cell-free expression would simplify the preparation of customized protein microarrays on demand as no purification of proteins would be necessary anymore. This could be a major advantage in scientific research as handling and storage of protein arrays still pose some challenges. With our system of cell-free expression the production of protein arrays could provide an easy method to work with freshly produced protein chips.
 +
As cDNA <sup><a class="fn_top" href="#fn__3" id="fnt__3" name="fnt__3">3)</a></sup> libraries are a common tool in basic research this can be easily combined with our system of cell-free expression and immobilization of proteins on a glass slide. With this set-up, screenings for potentially interacting proteins can be facilitated and improved by making use of multiplexing applications.
 +
</p>
 +
<p>
 +
In our iGEM project we were able to detect antibodies specific for two diseases: tetanus and salmonellosis - but these are only two out of 1000 diseases our DiaCHIP will hold in the future.
 +
</p>
 +
 
 +
<div class="link_button link_button_arrow">
 +
    <p><a href="https://2015.igem.org/Team:Freiburg/Results" title="Detection of tetanus" target="blank">Tetanus Detection</a></p>
 +
</div>
 +
 
 +
<div class="link_button link_button_arrow">
 +
    <p><a href="https://2015.igem.org/Team:Freiburg/Results/Diagnostics" title="Detection of Salmonellosis" target="blank">Salmonella Detection</a></p>
 +
</div>
  
  
 
<div class="footnotes">
 
<div class="footnotes">
 +
 +
<h3>References</h3>
 +
 
<div class="fn"><sup><a class="fn_bot" href="#fnt__1" id="fn__1" name="fn__1">1)</a></sup>
 
<div class="fn"><sup><a class="fn_bot" href="#fnt__1" id="fn__1" name="fn__1">1)</a></sup>
 +
<a class="urlextern" href="http://www.ncbi.nlm.nih.gov/pubmed/78929" rel="nofollow" target="_Blank" title="http://www.ncbi.nlm.nih.gov/pubmed/78929">Voller, A. Bartlett, A. Bidwell, D. E. (1978). Enzyme immunoassays with special reference to ELISA techniques. Journal of clinical pathology.</a></div>
 +
 +
<div class="fn"><sup><a class="fn_bot" href="#fnt__2" id="fn__2" name="fn__2">2)</a></sup>
 
<a class="urlextern" href="http://www.cancer.gov/about-cancer/causes-prevention/risk/infectious-agents/hpv-vaccine-fact-sheet" rel="nofollow" target="_Blank" title="http://www.cancer.gov/about-cancer/causes-prevention/risk/infectious-agents/hpv-vaccine-fact-sheet">HPV vaccine fact sheet</a></div>
 
<a class="urlextern" href="http://www.cancer.gov/about-cancer/causes-prevention/risk/infectious-agents/hpv-vaccine-fact-sheet" rel="nofollow" target="_Blank" title="http://www.cancer.gov/about-cancer/causes-prevention/risk/infectious-agents/hpv-vaccine-fact-sheet">HPV vaccine fact sheet</a></div>
−
</div>
+
 
−
</div>
+
<div class="fn"><sup><a class="fn_bot" href="#fnt__3" id="fn__3" name="fn__3">3)</a></sup>
−
</div>
+
<a class="urlextern" href="http://www.sciencedirect.com/science/article/pii/S0888754307002820" rel="nofollow" target="_Blank" title="http://www.sciencedirect.com/science/article/pii/S0888754307002820">Harbers, M (2008). The current status of cDNA cloning. Genomics.</a></div>
 +
 
 +
</div> <!-- close footnotes -->
 +
</div> <!-- close content box -->
 
</html>
 
</html>
−
<!-- Labjournal content ends here -->
 
 
{{Freiburg/wiki_content_end}}
 
{{Freiburg/wiki_content_end}}

Latest revision as of 00:40, 19 September 2015

""

Future Directions

Room for Improvement

The detection of antibodies in a blood sample is a versatile and widely applied method of today's diagnostics. Common methods include ELISA, an immunodiagnostic method based on the interaction of antibodies and corresponding antigens. As test reliability is crucially dependent on native-state proteins 1), ELISA plates require stable conditions for handling and storage. Maintaining these conditions is already quite expensive under European standards but becomes elaborate when working in tropical or arid regions.
Especially in regions, where hospitals are hard to reach and local medical treatment seldom relies on

physicians, it is necessary to reliably distinguish different illnesses as fast and accurate as possible. The treatment of potential epidemic pathogens requires an enormous logistic effort and differential diagnosis of a less potent pathogen may save thousands of dollars and prevent fear among people. Thus, it would be beneficial to have a large library of known antigens that is easy and cost-effective to store and to ship and is additionally functional as a reliable and selective tool in diagnostics.


The DiaCHIP - On the Way Towards Future Diagnostics

Our idea of how to tackle this problem is to use the unique properties of DNA as a robust information storage and combine it with cell-free expression inside a microfluidic device. At the same time, this device is used for detection of antibodies in a label-free manner. The antigens produced on demand directly before diagnosis are not only less prone to time-related denaturation but also enriched on the array due to a specific surface. Antibodies potentially present in the patient's blood are then observed by a new kind of detection method called iRIf (imaging Reflectometric Interference). The associated measurement device can be scaled down to a size smaller than a shoebox and a price affordable for almost everybody.
This portability makes the DiaCHIP useful for mobile applications especially in third world countries or regions of conflict where decisions for the appropriate treatment have to be taken fast and on-site. The potentially low costs of the device render it affordable for organisations with trained personnel such as Doctors Without Borders, replacing lots of bulky equipment and making it easier to operate in solitary areas.

Our project keeps many possible applications at hand if we will be able to further optimize the cell-free expression system and the specific binding to the surface for generating a protein array.

Determining the Status of Vaccination

Improving the device in terms of quantification may allow medical professionals to determine a patient's status of vaccination for a whole set of pathogens, thus possibly rendering some vaccination boosts unnecessary. The DiaCHIP could provide a tool for accurate analysis of the antibody titer of a person, thereby helping to keep up a constant protection against many diseases.
With the iRIf technology antibody-antigen interactions are detected. Nonetheless, there is no possibility of differentiating between antibodies that were already present due to a previous infection or vaccination, or ones that were developed due to an acute infection. A possible approach for dealing with this issue is the labeling of bound antibodies with proteins that bind specifically to one class of antibodies. Antibodies resulting form a previous infection or vaccination belong to the IgG class, those of an acute infection to the IgM class. Protein A may be a candidate for this purpose as it specifically binds to IgG but not to IgM. Additionally, conventional secondary antibodies targeting different classes of human antibodies may be used to cross-validate the results and thereby add an additional layer of reliablility to the test.

Investing further work on the DiaCHIP could make it possible to distinguish between vaccines from different manufactures by spotting different epitopes of one antigen on the slide. This offers the opportunity to determine whether the patient is vaccinated against a certain subtype of a virus. For example, the Human Papilloma Virus (HPV) shows several subtypes (such as HPV-6, HPV-11, HPV-16 or HPV-18) differing in the characteristics of the disease. Knowing the vaccination status of a patient for these different subtypes could help to asses the personal risks for several diseases 2) .

Pre-Pregnancy Testing

The DiaCHIP could additionally be used for pre-pregnancy testing where the evaluation of vaccination statuses for a whole set of diseases like rubella or whooping cough is crucial. In this case, the safety of the unborn child relies on the health status of the mother. Therefore, a lack of vaccination should be detected when a pregnancy is considered. With our DiaCHIP this may be a matter of one drop of blood and only one test, requiring a maximum of two to three hours including the expression of antigens on the slide.

Blood Sample Analysis

Blood samples from blood banks or blood donations can be checked for multiple infectious diseases in the same way. Since the required volume is very small, checks can be performed in short-time intervals and continuous monitoring of blood-quality may be possible.
Furthermore, one could develop a pre-test for critical diseases before donating blood. Like this, donations of infected blood could be prevented from the beginning.

Providing Access to Fresh Protein Arrays for Laboratory Use

Beyond applications in the field of clinics as such, the suggested method of cell-free expression would simplify the preparation of customized protein microarrays on demand as no purification of proteins would be necessary anymore. This could be a major advantage in scientific research as handling and storage of protein arrays still pose some challenges. With our system of cell-free expression the production of protein arrays could provide an easy method to work with freshly produced protein chips. As cDNA 3) libraries are a common tool in basic research this can be easily combined with our system of cell-free expression and immobilization of proteins on a glass slide. With this set-up, screenings for potentially interacting proteins can be facilitated and improved by making use of multiplexing applications.

In our iGEM project we were able to detect antibodies specific for two diseases: tetanus and salmonellosis - but these are only two out of 1000 diseases our DiaCHIP will hold in the future.

Tetanus Detection

Salmonella Detection

References

1) Voller, A. Bartlett, A. Bidwell, D. E. (1978). Enzyme immunoassays with special reference to ELISA techniques. Journal of clinical pathology.
2) HPV vaccine fact sheet
3) Harbers, M (2008). The current status of cDNA cloning. Genomics.