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Biosafety

Definition: "biosafety measures aim to prevent the unintentional exposure to pathogens and toxins, or their accidental release" ¹

Risk assessment for our Adeno-associated virus based system

In Germany the "Central Commission for Biological Security" (ZKBS) released three legally binding Risk Assessment satements for the Adeno-associated Virus ^26, ^27, ²⁸. Risk assessment in other countries may deviate from these decisions, so please inform yourself about the legal regulations on AAV in your country before using the Virus Construction Kit.

In Germany the Biological Safety Level(BSL) classifications for AAVs are:

Adeno-associated Virus 2, 3 and 5 have to be handled under BSL 1.
Adeno-associated Viurs 1, 4, 5, 7, 8, 9, 10 and 11 have to be handled under BSL 2.

This classification was developed based on the fact that only serotypes 2, 3 and 5 are isolated from humans and that their harmlessness has been confirmed in clinical studies. This general classification has to be rechecked when the virus contains gene sequences with a transforming protential.

Viral vectors systems packaging a vector plasmid that only contains the viral Inverted Terminal Repeats (ITRs) and providing the genes for Rep and Cap in trans (as it is the case for our system) are classified as BSL 1 if the following conditions are fullfilled:

The viral particles do not contain AAV derived sequences other than the ITRs
The viral particles do not contain Nucleotidesequences with a risk potential

We also investigated the legal regulations for AAV-2 Viral Vector systems in the United States. The guidelines of the National Institutes of Health (NIH) classify in the Appendix B³² AAV-2 Vector Systems as Risk Group 1 (RG1) agents that can be treated under BSL 1. In detail the appendix states "... adeno- associated virus (AAV) types 1 through 4; and recombinant AAV constructs, in which the transgene does not encode either a potentially tumorigenic gene product or a toxin molecule and are produced in the absence of a helper virus."

Other general observations with the Adeno-associated Virus 2 AAV-2)are:

In clinical studies the viral vectors were not dilivered to the gonades.
Vector sequences were not detectable in the patients blood or urine at an examination 48 h after an infection with AAV-2 ²⁹.
In absence of Rep proteins, the vector DNA stays extrachromosomal and is not frequently integrated.

Concluding all these informations and regulations, the project that we have designed in this year is clearly classified as BLS 1.

General biosafety regulation in Germany

Which specific biosafety rules or guidelines do you have to consider in your country?

In Germany all work that includes recombinant DNA technologies is regulated by the Gesetz zur Regelung der Gentechnik. This law regulates general aspects in the life sciences and refers for more precise interpretations in §4 to the Zentrale Kommission für die Biologische Sicherheit. The ZKBS is a commission composed of 20 technical experts that releases yearly statements to actual issues of biosafety. So far the ZKBS released three stratements affecting the work with Adeno-associated viral systems ^26, ^27, ²⁸. These documents were used to assess the dangers that could arise from our project to team members and the enviroment.

Is there a local biosafety group, committee, or review board at your institution? If yes, what does your local biosafety group think about your project?

At the Albert-Ludwigs-University Freiburg for all concerns of security the Stabsstelle Sicherheit is responsible and to contact if questions arise. Especially for questions of biological security Dr. Petra Markmeyer-Pieles is cognizant. We contacted her a first time befor the begin of our project in March when it was clear that the Adeno-associated Virus (AAV-2) was chosen as the topic of our project. At that time she proposed to do the cloning in the AAV-2 that is for sure to handle under biological security level 1 and to prepare everything for work under biological security level 2 to satisfy the precaution principle. The precaution principle was realized and all viral vectors that contained a modified capsid were handled under SII conditions until proven harmless. In August the planing of the project was completed, summarized in an Biosafety application³⁰ and handed to the department for biological security who approve the application in an official BSL1 confirmation³¹official BSL1 confirmation for our project.

Risk management

Would any of your project ideas raise safety issues in terms of: researcher safety, public safety, or environmental safety?

Our project was designed in a way that it avoids any serious safety issues as far as possible. When working with infectious particles a minimal risk for the researcher is allways present. This risk was minimized by restricting the transduced genes to fluorescent proteins and prodrug convertases that are already proven not to harm human cells in the absece of the corresponding prodrug. A potential danger for the public or the environment was minimized as much as possible by following strictly the rules of Good Laboratory Practice (GLP) and the abdication of using randomized insertions in the capsid and of replication potent viruses. Minimizing the risk for team members and the society was was allways one of the major concerns, especially because worries about undergraduate students manipulating a virus could arise. The security concept will be explained by quoting and explaining the six guiding principles for safe manipulation of Gene Manipulated Organisms (GMOs) as summarized in Kimman et al. ; 2008¹⁸.

1) Hazard recognition and identification Risk assessment has been done and all legal regulations were considered as described in the last paragraph.
2) Biological containment Biological containment means the usage of organisms with "reduced replicative capacity, inefectivity , transmissibility, and virulence"18. For our project only replicative deficient viruses were used, additional all modifications aimed to have a specific targeting of the resulting viral vectors for a specific cell type. This gain in specificity requires it to cut off the braod natural tropism resulting is an less infective virus copared to the wild type virus.
3) Concentration and enclosure All working steps for the preparation of viral vectors were carried out in a BSL II laboratory and within this laboratory work with the AAV was restricted to a separate Laminar flow cabinet type II. Cell culture and storage of the virus was also done in separate Freezers and incubators. All laboratories and epipment that contained viral vectors were specially marked, for example with a Biohazard warning signs.
4) Exposure minimization This aspect of the guiding principles can be sumarized under "operator protection"18. The Exposure minimization was achieved in our laboratory by wearing special labcoats for the SII laboratory and gloves that were desinfected and changed regualrely. During manipulation of viral vectors attention was payed to avoid droplets and especially aerosoles. A possible diversion of the viral vectors was avoided by cleaning all equipment when inserted or removed from the Laminar flow cabinet and after completion of the work task.
5) Physical containment The requirements for the physical containment were fullfilled by performing all manipulation on the AAV in an BSL II laboratory that guaranted a restriction of persons that entered the laboratory.
6) Hazard minimization For the AAV-2 there are no sugestive activitis because the possible danger that runs out of the AAV is comparably low, vaccination is not avilible and biomonitoring is not necessary.

Do any of the new BioBrick parts (or devices) that you made this year raise any safety issues? If yes, did you document these issues in the Registry? How did you manage to handle the safety issue? How could other teams learn from your experience?

Several composite parts that were assembled by our Team this year are alone capable of producing infectious viral particles when transduced together with a vector plasmid and a helper plasmid into AAV-293 cells. These special cells provide the adenoviral gene E1 stabily integrated in trans. These cells are not provided in the Virus Construction Kit nor availible in the Parts Registry and have to purchased from other laboratories or a commercial supplyer. For this reason we estimate the risk of a accidental transformation of AAV-293 cells with all three plasmids for negligible. Nevertheless we considered it useful to mark every BioBrick or Composite Part in the Registry that contributes to the production or is capable of producing viral vectors when transformed under the previously mentioned conditions.

Warning sign for part descriptions

Contribute to community discussions on what needs to go into a code against the use of our science for hostile purposes (see A Community Response)

Public Perception
importance of maintaining public legitimacy and support
apllications should demonstrate clear social benefits
not overhyped - anxiety and unrealistic hopes

psychological research into the concept of "identity-driven decision-making" (Torpman,2004) ¹⁹

Every grout has a set of norms: a code of conduct about what is acceptable beahviour (Jaques, 2004] ¹⁹

Trade-off between potential misuse and promising medical progress

Do you have any other ideas how to deal with safety issues that could be useful for future iGEM competitions? How could parts, devices and systems be made even safer through biosafety engineering?

In principle each research-project that bears any risks for engaged researchers, mankind or the environment should be treated under the precautionary principle as proposed ¹¹: "treat synthetic microorganisms as dangerous until proven harmless".
This would mean to work on such synthetic DNA containing Bio Bricks at least under Biological security levels two.
Additional to this secure working environment the system itself can be optimized according to biosafety aspects, means to reduce it's viability outside the laboratory. This aim can be approached by reducing the systems ability to evolve, proliferate and interact with it's environment. A common method to achieve this goal is to engineer microorganisms in a way that they depend on nutrients that can't be found in the environment in sufficient amount.

Biosecurity

Def: "measures focus on the prevention of theft, misuse , or intentional relese of pathogens and toxins" ¹

The malignant use of biological agents in history

The misuse of biological agent as weapons in warfare is a fear spreading companion in the history of mankind, ranging from the well-poisoners in prehistoric times to bio-terrorists present days. The following brakt intends to give a short outline of the major events²²:

First systhematic use of chemical weapons during the first world war
The 1918 flu pandemic lasted from March 1918 to June 1920 and killed approximately 50 Million people around the world. Rumors circulated that this pandemic is caused by the other combatant nation.
"Prohibion of the Use of Asphyxiating, Poisonous or other Gases and of Bacteriological Methods of Warfare" was signed on 19 June 1925²²
Several combatant nations of the second world war established biological warfare programs.
The range of the Japanese biological warfare program lead several nations to expand their own biological warfare program.
Limited military use²² and the advances in molecular biology (e.g. the first isolatin of a gene and the discovery of the restriction enzymes in 1969) lead to the "Convention on the Prohibion of the Development, Production and Stockpilling of Bacteriological (Biological) and Toxin Weapons and on Their Destruction " (BTWC) on 10 April 1972.
''"develop, produce, stockpile or otherwise acquire or retain: ... Microbial or other biological agents, or toxins whatever their origin or method of production, of types and in wantities that have no justification for prophylactic, protective or other peaceful purpose..." ''³
Breach of the BTWC by the Soviet Union which continued their offensive biologicla warfare programm
Stop of the biological warfare Program "Biopreparat" accompanies the Dissolution of the Svoviet Union in 1991
Antrax attacks in the USA in 2001

Broad avilibility of knowledge

n the life sciences information has allways been freely acessible for everybody who is interested in the results of a particular research project. The combination of this global availibility with the new possibilities of the internet broad for literature search and availibility of gene sequences made it easiere to collect informations for a possible misuse.
For the overwhelming majority this open availibility is absolutely desirely but on the other hand there are also examples of research results that bear a very high risk to be misused.
Following we present the three most controversial discussed publications that could also be read as a "How to create your own bioweapon".

Mousepox Virus in Australien

The Australian research group around Jackson et al. ; 2001 ¹⁶inserted the coding region of the IL-4 gne into the genome of mousepox. They hoped to create a virus that sterilizes mice and thus provides a means for pest control. Contrarely to their expectations they had created a superstrain that killed even naturally resistent mice and mice that had been vaccinated against normal mousepox. This discovery could potentially be used to make smallpox resistant to potential vaccines.

Synthesis of a Polio Virus

At the State University of New York Cello et al. ; 2002 ⁰⁵ synthesized a "living" polio virus from scratch. Especially the Supporting Online Material caused worried remarks because it precisely describes how to assemble a virus from small oligo nucleotides. The authors jusifyed their project by declaring that they:

"made the virus to send a warning that terrorists might be able to make biological weapons without obtaining a natrual virus"¹⁷

Reconstitution of the Spanish Flu

Influenza hospital for american soldiers

At the Center for Disease Control and Prevention (CDC) the group around Tumpey et al. ; 2005²⁴ published that they had sequenced and recreated the pandemic Spanish Flu Virus of 1918 which killed 20-50 million people. The publication of the sequence provoked several very different responses that can only be partially be quoted here. The controversial noticed outrider of the Synthetic Biology Craig Venter seen in the new virus

"the first true Juressic Parc scenario" ²

The Institute Professor at the MIT Philip A. Sharp supported the publication because he:

"belive[s] that allowing the publication of this information was the correct decision in terms of both national security and public health" ¹²

Wheras v. Bubnoff; 2005²⁵ critisizes the CDS for it's careless regulations for the shipment of viruses and the willingness to propagate highly virulent viruses. This causes in his opinion the risk of possible accidents resulting in the release of the virus to the environment.

Broad avilibility of material

Szenarios of attack

Conclusion

Include something in your project description and presentations that demonstrates that you have thought about how others could misuse your work.

For sure there is allway the possibility that knowledge to produce transgene viral vectors could be used to produce bioweapons. Therefor it was important for us to use a system that does not bear the risk that someone could use it for evil purpose. In the case of the Adeno-associated virus the very limited packaging capacity is the major reason that excludes it from the list of agents that could realistically be used for the pruduction of bioweapons. Even a fully replication potent AAV will depend on the coninfection of a helpervirus and is therefore not suitable for a fast propagation in an population. Additional to this point we concentrated our project on the retargeting of the virus - means to make the broad tropismn more narrow and to decrease the transduction efficiency in the most cases. This modification is usually mainly required for medical purposes. Also we did neither investigate possibilities to shield the vector from the immune system of potential host nor ways to bypass an existing immunity.

Team:Freiburg Bioware/Safety