Difference between revisions of "Team:SHSBNU China/Demonstrate"

Demonstration

引用改成正文，成本对比改成表格，加上示意图，突出重点

Introduction

Our human practice included an online-and-offline survey, asking the public about their general information, experience and knowledge on intestinal inflammation, and their thoughts about using probiotics to detect and treat intestinal inflammation. We found that generally people are more concerned about the following aspects: the product’s safety, harm to human body, sensibility, price, and response time. Thus, we decided to demonstrate our way of dealing with these problems and how we can meet the public’s needs.

Safety

Safety is always the first concern that is raised when a new product is proposed. Our bacteria are generally qualified as safe.

First, E. coli Nissle 1917, the bacterial strain intended for administration to patients, is generally considered as safe, and even one of the best investigated therapeutically applied E. coli strains worldwide. E. coli Nissle 1917 is non-pathogenic, which means that it does not cause any disease or produce any toxins. E. coli Nissle 1917 does not possess any antibiotic resistance plasmids and is stable, is a poor recipient of foreign DNA, especially in the form of antibiotic resistance- and other promiscuous plasmids . Despite the safe properties of Nissle 1917, we are still planning to do some engineering on its cryptic plasmids (引用) to make it produce an appropriate amount of DNase, so that when the engineered bacteria are administered, they can automatically destroy their own DNA after a specific time has passed or an appropriate environment is sensed.

Second, we are planning to put the bacteria inside gastro-resistant hard capsules to make sure that they do not escape into the environment. These capsules permit the transition of small chemical compounds through its wall, and we are able to control when (at what pH) the capsule will be dissolved. (Fred A. Hines at all, 2011)

Sensitivity

Our engineered bacteria show distinct color-depth difference when exposed to different concentrations of tetrathionate and thiosulfate, ranging from 0.01 mM to 1mM. (找周浩宇要亮度/显色度实物图和模拟数据图) And as has been shown in a dextran sodium sulfate (DSS) mouse model, the two-sensor system was able to sense and report the tetrathionate and thiosulfate concentrations by expressing sfGFP (Kristina N-M Daeffler at all, 2017) . This is indirect proof that our system is theoretically able to report different concentrations of tetrathionate and thiosulfate.

Price and Response Time

Our bacteria would already be modified and propagated to an appreciable quantity when they are ready to be commercialized, so that the job for each seller would be just cultivating the bacteria, making the capsules, and transporting them at 2-8 °C. Generally speaking, this whole process wouldn’t be very expensive compared to the current methods of intestinal inflammation testing. We used the price of Mutaflor as a model for comparison. Mutaflor sells 20 capsules for $28.95. However, since our patients would only need one capsule for inflammation testing, the principal production and distribution cost would be around $1.5 per capsule . This, is much cheaper than any currently commercialized methods.

Blood testing (without insurance) would range from $700 to $2589 ; stool testing would generally cost $5 - $100 . Testing in hospitals is generally more expansive, and in most hospitals