Construction of a Platform for the Development of Pharmaceutical and Medical Applications Using Transgenic Silkworms

We have been constructing a platform for the development of pharmaceutical and medical applications using the domesticated silkworm, Bombyx mori, as a new animal model for drug development and evaluation. Because silkworm larvae originally have the capacity to synthesize up to 0.5 g of silk proteins, genetically modified silkworms (transgenic silkworms) are expected to have high potential in the production of recombinant silks/proteins. An innovative method for generating transgenic silkworms was established in 2000, and ever since this epoch-defining technological development, longstanding efforts have succeeded in developing novel silks that enable the manufacture of new textile materials for regenerative medical uses. Furthermore, we have succeeded in developing a new system of recombinant protein production. This recombinant protein production system is currently capable of producing a maximum of approximately 15 mg recombinant protein per silkworm larva. Transgenic silkworms have also been shown to produce a wide variety of useful proteins, including antibodies and membrane proteins. Some of these recombinant proteins have been in commercial use since 2011. In addition, we have been developing transgenic silkworms as a novel animal model for testing medicines based on metabolic similarities between silkworms and mammals. These applications show the suitability and potential of transgenic silkworms for medical use. Here, we will describe the challenges faced in creating a transgenic silkworm-based platform for pharmaceutical and medical applications.