Biological control and controlling biology

7 October 2016

Frank Doyle
School of Engineering and Applied Sciences
Harvard University


In this talk I will touch on complementary aspects of "control" in biology: the systems analysis of regulatory mechanisms, and the use of feedback algorithms to deliver a drug in an optimal fashion.

Robustness, the ability to maintain performance in the face of perturbations and uncertainty, is a key property of living systems. While 'homeostasis' has long been recognized as an important phenomenon, the molecular and cellular bases of robustness have only recently begun to be understood. Biology and engineering employ a common set of basic 'control' mechanisms to achieve such robust regulation, namely redundancy, feedback control, modularity and hierarchies to ensure robust performance. New systems theoretical approaches to complex engineered systems are required that allow the reverse engineering of general design principles that can provide insights into cellular robustness. I will illustrate these principles with the example of robust timekeeping in neurons controlling circadian rhythms.

More than 30 years ago, the idea of an artificial endocrine pancreas for patients with type 1 diabetes mellitus (T1DM) was envisioned. The closed-loop concept consisted of an insulin syringe, a blood glucose analyzer, and a transmitter. With the advent of continuous glucose sensing, which reports interstitial glucose concentrations approximately every minute, and the development of hardware and algorithms to communicate with and control insulin pumps, the vision of closed-loop control of blood glucose is approaching a reality. I will outline the difficulties inherent in controlling physiological variables, the challenges with regulatory approval of such devices, and will describe a number of systems engineering algorithms we have tested in clinical experiments for the artificial pancreas.

current theory lunch schedule