Project Description

Lyme-AID: Genetically Engineered Detection of Borrelia burgodferi, the causative agent of Lyme Disease

Lyme-AID logo

What is the 2023 USAFA iGEM Project?

This year, the USAFA iGEM team was originally torn between many great ideas. It took much time and deliberation to narrow down the number of ideas. After reviewing countless publications and talking with a survivor of Lyme Disease, we ultimately decided to press on with Lyme Disease detection using biosensors.

Lyme Disease is a very serious illness that afflicts people across the globe, and can lead to severe joint pain, nerve pain, and inflammation of the brain and spinal cord among a slew of other ailments (Lyme Disease, 2022). In the United States alone, 500,000 cases are reported annually (Data and surveillance 2022). The bacteria responsible is Borrelia burgdorferi. It is transmitted through tick bites. Once bitten, the bacteria often remain undetected due to its mobility and surface proteins (Anderson & Brissette, 2021). In many cases, by the time someone discovers that they are infected, they are often unable to make a full recovery – and in some cases, die. Therefore, a method for early detection is needed.

In addition, our unique perspective as a US military service academy made it more evident that a solution to early detection was necessary. In some cases, they will be deployed in the field, far from medical facilities. While Lyme Disease can currently be tested for in a lab setting by using PCR4, there is no fast, user-friendly, on-the-spot, simple detection method that can be used in the environment where the tick bite occurred (Schutzer et al., 2018). Thus, our commitment to the warfighter’s needs also demanded a solution that could be used in the field for military members, but also one that could be expanded to those that may live in more rural areas and do not have access to medical labs. In any case, providing an additional layer of information, so that they may react quicker and seek additional medical treatment if needed is of the utmost importance.

As we moved into additional research, the first problem that we encountered was how to test our method of detection while not having Borrelia burgdorferi directly on hand due to it being BSL-2 (Caimano, 2017). While most colleges operate BSL-2 labs, the US Air Force Academy is unique in its military organization, and thus can only operate BSL-1 labs. Our solution to this challenge consisted of genetically engineering E. coli bacteria to display B. burgdorferi’s naturally expressed surface proteins OspA and OspC on their cellular membranes to work as an analog for B. burgdorferi (Srivastava & de Silva, 2008). By doing this, we could investigate creating a biosensor that can detect the surface proteins but on a BSL-1 organism. This would also open up this kind of research to more laboratories that might not have access to the expensive equipment required for BSL-2 laboratories.

In this project, we aim to attract, inhibit, and detect B. burgdorferi. In a sense, we want to AID the patient in the early stages of Lyme Disease so they do not suffer from the chronic symptoms that occur in advanced stages of the disease. So how did we go about this?

Our project, Lyme-AID, will be in the form of a bandage that is to be applied directly onto a tick bite wound. It will serve as a convenient and cost-effective means of detecting B. Burgdorferi in the body. This will be a great tool for inhabitants of rural areas and people doing work in an environment that does not have readily available access to a lab. How this device will work is broken up into two phases: attract/inhibit and detect.

        The first phase, attract and inhibit, utilizes Salp12, which is a salivary gland protein from the tick Ioxodes scapularis. This protein is a chemoattractant of B. burgdorferi (Murfin et al., 2019). The bandage will have Salp12 expressed by E. coli and it will bind to B. burgdorferi. This binding attracts the bacteria to the initial wound site rather than having it spread throughout the body as it normally does. This in turn inhibits the spread of the bacteria.
Salp12 attracts bacteria to the wound site
Detection of B. burgdorferi
        The second phase, detect, utilizes an aptamer-mediated biosensor. This biosensor works by having an aptamer, which is a short strand of DNA that can bind to a target protein, bind to OspA & C on B. burgdorferi (Anderson & Brissette, 2021). When this happens, the aptamers then associate with gold nanoparticles which leads to a conformational change, leading to the bandage turning red. This red color will signify to the user that they are positive for B. burgdorferi and should seek medical attention.

Overall, Lyme-AID will be useful in providing the patient with more information about their condition, specifically whether the causative agent of Lyme Disease is present in their body. From this they will be able to make educated decisions on whether to seek immediate treatment due to a positive test. This information can then be provided to medical professionals to help point them in the right direction with regards to how to treat the tick bite.

References

Anderson, C., & Brissette, C. A. (2021). The brilliance of borrelia: Mechanisms of host immune evasion by lyme disease-causing spirochetes. Pathogens, 10(3), 281. https://doi.org/10.3390/pathogens10030281

Caimano, M. J. (2017). Generation of mammalian host-adapted borrelia burgdorferi by cultivation in peritoneal dialysis membrane chamber implantation in rats. Methods in Molecular Biology, 35–45. https://doi.org/10.1007/978-1-4939-7383-5_3

Centers for Disease Control and Prevention. (2022a, August 5). Lyme disease. cdc.gov. https://www.cdc.gov/ticks/tickbornediseases/lyme.html

Centers for Disease Control and Prevention. (2022b, August 29). Data and surveillance. cdc.gov. https://www.cdc.gov/lyme/datasurveillance/index.html?CDC_AA_refVal=https%3A%2F%2Fwww.cdc.gov%2Flyme%2Fstats%2Findex.html

Murfin, K. E., Kleinbard, R., Aydin, M., Salazar, S. A., & Fikrig, E. (2019). Borrelia burgdorferi chemotaxis toward tick protein Salp12 contributes to acquisition. Ticks and Tick-Borne Diseases, 10(5), 1124–1134. https://doi.org/10.1016/j.ttbdis.2019.06.002

Schutzer, S. E., Body, B. A., Boyle, J., Branson, B. M., Dattwyler, R. J., Fikrig, E., Gerald, N. J., Gomes-Solecki, M., Kintrup, M., Ledizet, M., Levin, A. E., Lewinski, M., Liotta, L. A., Marques, A., Mead, P. S., Mongodin, E. F., Pillai, S., Rao, P., Robinson, W. H., … Branda, J. A. (2018). Direct diagnostic tests for lyme disease. Clinical Infectious Diseases, 68(6), 1052–1057. https://doi.org/10.1093/cid/ciy614

Srivastava, S. Y., & de Silva, A. M. (2008). Reciprocal expression of ospa and ospc in single cells of borrelia burgdorferi. Journal of Bacteriology, 190(10), 3429–3433. https://doi.org/10.1128/jb.00085-08