A unique digital microfluidic electroporation (EP) system successfully demonstrates higher transgene expression than that of conventional techniques, in addition to reliable productivity and feasible integrated processes. By systematic investigations into the effects of the droplet EP conditions for a wild-type microalgae, 1 order of magnitude higher transgene expression is accomplished without cell wall removal over the conventional bulk EP system. In addition, the newly proposed droplet EP method by a droplet contact charging phenomena shows a great potential for the integration of EP processes and on-chip cell culture providing easy controllability of each process. Finally, the implications of the accomplishments and future directions for development of the proposed technology are discussed.

Stem cell-like colon cancer cells (SCCs) pose a major challenge in colon cancer treatment because of their resistance to chemotherapy and radiotherapy. Oncolytic virus-based therapy has shown promising results in uncured cancer patients; however, its effects on SCCs are not well studied yet. Here, we engineered a cancer-favoring oncolytic vaccinia virus (CVV) as a potent biotherapeutic and investigated its therapeutic efficacy in terms of killing SCCs. CVV is an evolved Wyeth strain vaccinia virus (EVV) lacking the viral thymidine kinase. SCC models were established using human or mouse colon cancer spheres, which continuously expressed stemness markers. The cancer-favoring characteristics and different cytotoxic pathways for killing cancer cells successfully overrode general drug resistance, thereby killing colon cancer cells regardless of the presence of SCCs. Subcutaneously injected HT29 spheres showed lower growth in CVV-treated models than in 5-Fu-treated models. Intraperitoneally injected CT26 spheres induced tumor masses in the abdominal region. CVV-treated groups showed higher survival rates and smaller tumor mass formation, compared to 5-Fu-treated groups. Interestingly, the combined treatment of CVV with 5-Fu showed improved survival rates and complete suppression of tumor mass. The CVV developed in this study, thus, effectively suppresses SCCs, which can be synergistically enhanced by simultaneous treatment with the anticancer drug 5-Fu. Our novel CVV is highly advantageous as a next-generation therapeutic for treating colon cancer.

Herein, we exploited a bioinspired M13 bacteriophage as an angiogenic nanofiber for soft tissue engineering applications. We demonstrated that engineered phage nanofibers induce angiogenesis with specific biochemical and topological cues. Specifically, nanofibrous phage structures provided a novel therapeutic platform for stem cell technologies in ischemic diseases.

Engineered vaccinia virus-based therapy shows promising results in patients with advanced hepatocellular carcinoma, although a strategic virus design for the metastatic liver and the study of its efficacy in treating the cancer has not been well assessed. In this paper, we proposed a simple and strategic virus design for targeting metastatic hepatocellular carcinoma. We developed an evolutionary cancer-favoring engineered vaccinia virus (CVV, which is produced by repeated selective replication in cancerous tissues and then deleting viral thymidine kinase genes) and investigated its therapeutic effects on metastatic liver cancer. The expression of the cell surface marker, CD44, which is associated with cancer stem cells, seems to be correlated with the cells’ metastatic characteristics; cellular migration, epithelial-mesenchymal transition (EMT) expression and liver tumorigenicity. The highly metastatic and tumorigenic Sk-Hep-1 cell line was selected and injected directly onto the liver tissue to develop a liver-to-colon metastasis model. In an animal study, the subjects were treated with sorafenib, CVV, or sorafenib with CVV. Metastatic regions were interestingly rare in the CVV-treated groups (i.e., CVV or sorafenib with CVV) whereas metastatic regions existed in the sorafenib-treated group. From results, we concluded that our simple strategy of developing a cancer-favoring virus can successfully eradicate metastatic liver cancer cells, provided that our CVV can be a promising therapeutic virus that targets metastatic liver cancer.

Here, we demonstrated chimeric adeno-associated virus (chimeric AAV), AAV-DJ-mediated cardiovascular reprogramming strategy to generate new cardiomyocytes and limit collagen deposition in cardiac fibroblasts by inducing synergism of chimeric AAV-expressing Gata4, Mef2c, Tbx5 (AAV-GMT)-mediated heart reprogramming and chimeric AAV-expressing thymosin β4 (AAV-Tβ4)-mediated heart regeneration. AAV-GMT promoted a gradual increase in expression of cardiac-specific genes, including Actc1, Gja1, Myh6, Ryr2, and cTnT, with a gradual decrease in expression of a fibrosis-specific gene, procollagen type I and here AAV-Tβ4 help to induce GMT expression, providing a chimeric AAV-mediated therapeutic cell reprogramming strategy for ischemic heart diseases.