Integrating an Islet-Based Biosensor in the Artificial Pancreas: In Silico Proof-of-Concept
Résumé
Objective: Current treatment of type 1 diabetes by
closed-loop therapy depends on continuous glucose monitoring.
However, glucose readings alone are insufficient for an artificial
pancreas to truthfully restore nutrient homeostasis where
additional physiological regulators of insulin secretion play a
considerable role. Previously, we have developed an
electrophysiological biosensor of pancreatic islet activity, which
integrates these additional regulators through electrical
measurements. This work aims at investigating the performance
of the biosensor in a blood glucose control loop as potential in
silico proof-of-concept. Methods: Two islet algorithm models
were identified on experimental data recorded with the
biosensor. First, we validated electrical measurement as a means
to exploit the inborn regulation capabilities of islets for
intravenous glucose measurement and insulin infusion.
Subsequently, an artificial pancreas integrating the islet-based
biosensor was compared to standard treatment approaches using
subcutaneous routes. The closed-loop simulations were
performed in the UVA/Padova T1DM Simulator where a series
of realistic meal scenarios were applied to virtual diabetic
patients. Results: With intravenous routes, the endogenous islet
algorithms successfully restored glucose homeostasis for all
patient categories (mean time in range exceeds 90%) while
mitigating the risk of adverse glycaemic events (mean BGI < 2).
Using subcutaneous routes, the biosensor-based artificial
pancreas was as efficient as standard treatments, and
outperformed them under challenging conditions. Conclusion:
This work validates the concept of using inborn pancreatic islets
algorithms in an artificial pancreas in silico. Significance:
Pancreatic islet endogenous algorithms obtained via an
electrophysiological biosensor successfully regulate blood glucose
levels of virtual type 1 diabetic patients.