Our project makes significant contributions to the iGEM community by enriching the iGEM parts libraries, improving technologies, providing prediction models, and promoting access to synthetic biology in different communities. Specifically, we have:

1. New Surface Display System

2. SLC Circuit

3. Bio-Switch System

We modified an electrotransformation method to improve the plasmid transformation efficiency of Salmonella.

We created predictive models to forecast the efficiency of bacterial therapies and the population dynamics of bacteria during treatment.

Through our integrated human practices, we reached out to diverse communities, promoting access to synthetic biology and fostering broader engagement. We organized educational activities, laboratory tours, and poster exhibitions to engage the public, students, and scholars. These efforts aimed to break down barriers and make synthetic biology more accessible and inclusive.

We sincerely hope that our work this year will inspire and assist many iGEMers and synthetic biologists. At the same time, we aim to extend the impact of our program to a wider audience, encouraging communities from other fields to actively explore new cancer therapies. By sharing our knowledge and resources, we hope to contribute to the advancement of synthetic biology and the development of innovative solutions for global health challenges.

In our research, we identified and utilized two surface display systems, Lpp-OmpA and Non-OmpA, for Gram-negative bacteria such as Salmonella and E.coli. These systems enable the display of single-chain variable fragments (scFv) on the bacterial surface, significantly enhancing their targeting and invasion efficiency in cells with specific antigens.

To ensure precise intracellular delivery, we employed the SPI2 promoter (PssseJ promoter) from the Salmonella genome to induce intracellular self-lysis after the bacteria invade the target cells. This mechanism ensures that the therapeutic cargo is released precisely within the target cells.

In the Bio-Switch system, we followed the "closed-loop" model in translation, drawing on the design from Dr. Mingqi Xie's lab. Different constitutive protein association pairs were used to connect various components, forming a closed loop. The specific intracellular signal is recognized by two antibodies positioned at opposite sides of the loop, ensuring precise regulation of gene expression.

To ensure the safety of our experiments and the therapy, we added an SLC circuit to Salmonella VNP20009, so that its population will be controlled within a safe level when growing in human bodies.

For more details, please see our Parts Page.

In this year's iGEM project, we often transformed more than one plasmid (e.g., Lpp-OmpA-scFv with LuxI-GFP, etc.) into both E.coli and Salmonella. At the beginning of the experiment, we used the original chemical transformation method. However, the ratio of positive clones obtained was low when conducting transformations on Salmonella. Therefore, we prepared our own Salmonella STABLE competent cells suitable for electrotransformation and developed a protocol with higher transformation efficiency. This protocol can be used as a reference for other teams in the iGEM community.

For more details, please see our Experiments Page.

The mathematical model is a crucial component of the Tumor-Targeting Salmonella-Mediated Apoptosis Therapy project, as it allows for a quantitative analysis of key processes involved in the treatment. The model breaks down the bacterial diffusion, growth, and secretion dynamics in the tumor microenvironment, as well as the bactericidal effects on cancer cells. By incorporating factors such as bacterial movement, immune interactions, and the release of therapeutic agents, the model provides insights into how the engineered Salmonella behaves within a tumor. This enables the team to predict the most effective dosing strategies, timing, and tumor penetration, optimizing the treatment's effectiveness against different types of cancers.

Moreover, the model also simulates the suicide mechanism of the bacteria and the subsequent release of BAX proteins, which induce cancer cell apoptosis. This predictive approach offers a deeper understanding of the system's biological responses over time. It can guide the team in fine-tuning the components of their therapy, such as improving the bacteria's ability to target cancer cells, enhancing its metabolic activities, and ensuring effective apoptosis induction. These insights help the project move toward a more precise and personalized cancer therapy, contributing to the development of novel solutions for difficult-to-treat cancers.

From a societal perspective, the mathematical model plays a pivotal role in advancing the future of targeted cancer therapy. It allows researchers to minimize risks as much as possible and refine therapeutic strategies before clinical application, reducing the trial-and-error process in drug development. By optimizing treatment protocols through simulations, the model can significantly reduce the time and cost associated with developing novel cancer treatments, ultimately leading to more accessible and affordable care for patients with liver cancer, metastatic breast cancer, and other aggressive cancers.

In doing so, the model's contribution is no less than the laboratory's, offering hope for more effective, targeted, and less invasive cancer therapies in the broader medical community. By providing a robust framework for understanding and optimizing the treatment, the model supports the development of therapies that can be tailored to individual patients, enhancing the overall efficacy and safety of cancer treatments. This not only advances scientific knowledge but also has the potential to improve patient outcomes and quality of life.

For more details, please see our Model Page.

One of the main contributions of our project to synthetic biology is to enhance both the subjective appreciation and objective acquisition of knowledge regarding the innovative application of gene-edited bacteria in tumor therapies.

Subjectively, by emphasizing the pivotal role of synthetic biology techniques for tumor treatment and highlighting the importance of treating tumors, our project elucidates the significance of the field of synthetic biology, which contributes to people's recognition and appreciation of it.

Objectively, our project aims to break down barriers that hinder people from accessing cutting-edge knowledge in synthetic biology. We are committed to making synthetic biology more accessible and inclusive by entering school campuses to popularize new therapies for tumors, leading the public to visit the laboratory and explaining to them, and holding poster exhibitions on synthetic biology.

By consulting with the science popularization team and adopting their suggestions, we have provided four engaging and unforgettable science popularization courses for primary and secondary school students. The themes ranged from simple tumors and their treatment methods to incorporating knowledge of synthetic biology. We not only focused on knowledge output but also on feedback. We taught them to use their imagination to design plasmids with specific functions—even elementary school students can design them.

We have also actively guided primary and secondary school students as well as the general public visiting the biology laboratory at Westlake University multiple times, from explaining the principles and functions of various instruments to the popularization of synthetic biology.

In addition, we held a poster exhibition on synthetic biology to encourage more scholars in the field to not only exchange ideas with each other but also promote synthetic biology-related knowledge to the public.

Through educational activities and social interaction, our project creates a two-way exchange of knowledge and ideas. The feedback collected from participants is used to improve educational methods and activity design, promoting continuous improvement and responding to social needs.

In summary, our project contributes to synthetic biology by raising awareness of global health issues, making it easier to appreciate, and providing a platform for different forms of popularization, ultimately promoting a better understanding of tumors and their treatment methods.

For more details, please see our Human Practices Page.