APPOllO E.Cotector

To enhance the efficiency of diagnosis and provide reference for proper usage of targeted drugs and combination therapy, we come up with the idea of detecting multimarker at the same time and this was how our marvelous E.Cotector was born. This year, NCTU_Formosa commits to creating a multimarker diagnosis platform via scFv as probes for helping physicians to determine and prescribe the usage of targeted drugs in cancer patients, especially the monoclonal-antibody-targeted drugs.

Customized Detection Platform

This year, APOllO, introduce a revolution customized detecting platform. We call it the E.Cotector.

We built three individual biobrick libraries of scFv probes, color signals and Gold Binding Polypeptide (GBP) for the customized detection platform. Probes detect the target we want. Fluorescence protein or chromoprotein expresses signal for observation. GBP acts as a bridge to connect our product to gold, which enables our product to be applied to biosensors. Our customers can spontaneously choose from our libraries, pair up any biobricks. Next, comes the most crucial part of our project. Our team will then co-transform the plasmids into E. coli. Our customized detection platform, The APOllO E.Cotector, is therefore born. By co-transforming plasmids, it not only helps us customize our product every which way for our customers but also brings us a major advantage in our manufacturing procedure. We no longer have to build lengthy biobricks, which tremendously increases our manufacturing efficiency.

Single chain variable fragment as probe

In our product, we chose Single chain variable fragment (scFv) Abs as probes to detect. ScFv are one of the recombinant antibody (rAb) fragments, which are popular therapeutic alternatives to full length monoclonal Abs. Compared to generating whole Abs from animal cell culture, scFv are smaller and can be expressed rapidly, economically and in large quantities in a bacterial host, such as E. coli. A scFv possesses the complete antigen binding site, which contains the variable heavy (VH) and variable light domain of an antibody. The VH domain is linked to a VL domain by an introduced flexible polypeptide linker. A scFv is capable of binding to the target antigens with an affinity similar to that of the parent mAb. Since scFv fragments contain specific antigen binding units, scFv fragments show tremendous versatility and importance in human therapeutics and diagnostics.^[1] In addition, scFv fragments can be envisaged to be applied in the non-pharmaceutical sector, such as in food, cosmetic or environmental industries. The unique and highly specific antigen-binding ability might, for example, be exploited to block specific enzymes (e.g. enzymes that cause food spoilage), bacteria (e.g. in toothpaste or mouthwashes) or to detect environmental factors present in very low concentrations (as biosensors).^[2]

Figure 1.

According to the statistics, the usage rate of targeted drug therapy has increased within ten years. In Figure 2, in 2003, targeted drug therapy is not commonly used compared with other therapies, accounting for only 11% usage. Over one decade, it is estimated that the usage of targeted drug therapy dramatically increases to 46%. It indicates targeted drugs therapy is a potential growing field and will become the commonly used therapy in cancer treatments in the near future.

Figure 2. The usage of targeted drugs.

The concept of combination therapy

Although targeted drugs treatments can lead to the dramatic regressions of solid tumors, the responses are often short-lived because resistant cancer cells arise after a period of treatment. The major strategy proposed for overcoming the resistance is combination therapy.^[7] The clinical and preclinical researches further indicated that targeted drug therapy combined with another targeted drug therapy or other types of therapies to treat cancers simultaneously may attain greater effects than using only one therapy. With the concept of combination therapy, we can not only improve the treating effect but also reduce the occurrence of cancer cells resistance toward the targeted drugs as there are less probability that a single mutation will cause cross-resistance to both drugs.^[8]