Lecture, four hours; discussion, one hour; outside study, seven hours. Examination of how to design cells and cellular systems to perform therapeutic tasks in complex physiological environments. Discussion of immune system as case study of engineering functionality based on certain required specifications (e.g., not attacking self, recognition of pathogens, preventing cancer). Discussion also of methods and techniques used to genetically modify, separate, and analyze cells, which--just like in chemical synthesis and purification of drugs--are important to creating therapies with well-defined properties based on cells. Letter grading.