Abstract
The living body is composed of numerous cells that function cleverly under various network to maintain homeostasis. It is especially surprising that bioactive molecules such as hormones and cytokines have temporal, quantitative, and local targets in living body. Regarding the bioactive molecules as drugs, biosynthesis function, sensor function and controlled release function of bioactive molecules which are inherent in living cells are ideal of drug delivery system. We have studied the development of cytomedicine, a concept which involves using intelligent particles, living cells as carriers of bioactive molecules. Previously we reported that this cytomedicine was very effective as an in vivo long-term delivery system for bioactive molecules in animal model experiment. However the cytomedicine we studied so far produced and secreted bioactive molecules and functioned only sustained release system. The biggest benefit of cytomedical therapy is that we can strictly control blood concentration of drugs and can avoid frequent administration of drugs by utilization of various functions of living cells such as sensor function. In this study, we examined the biocompativility of alginate-poly(L) lysine-alginate (APA) microcapsules as the immobilized devices of cells for cytomedicine. Moreover, to evaluate the possibility of cytomedical therapy for diabetes mellitus using microencapsulated pancreatic β cell lines (MIN6 cells and βTC6-F7 cells) with glucose sensor, viability and glucose responsiveness of microencapsulated MIN6 cells and βTC6-F7 cells were examined in vitro. These APA-microencapsulated cells maintained glucose sensor and should good viability at least three months. This results suggest that cytomedicine using microencapsulated pancreatic β cell lines with glucose sensor is useful for therapy for diabetes mellitus.
