Fig. 7: The impact of oxygenation on the metabolic function of pancreatic islets encapsulated within the BEAM system in an allogeneic rat model.

A A schematic illustration of experimental design. Current, voltage, and battery level were wirelessly spot measured via IR communication. B A digital image demonstrating the BEAM system assembly on a diabetic rat. (1) A pocket on the back of a jacket worn by the rat to secure the iEOG and an electronic box. (2) The oxygen transportation tubing running from iEOG, underneath the jacket to the (3) cell encapsulation pouch implanted in the subcutaneous space of the rat. C Operating current (red) and voltage (blue) of the iEOG recorded during 88-day study from the electronics memory. D Cumulative volume of oxygen generated from the iEOGs used on the rats over a 24-h period (n = 4). E Non-fasting blood glucose levels of rats implanted with a cell encapsulation pouch without oxygen supplementation (n = 4). F Non-fasting blood glucose levels of rats received implantation of a BEAM system (n = 6). G Body weight changes of rats received implants with or without supplemental oxygenation. In F, G, black dots represent NBG levels/body weight changes before implantation while green dots represent NBG levels/body weight changes during continuous oxygenation, and red dots represent NBG levels/body weight changes measured without oxygenation or after the oxygenation cessation. Blue arrows mark the timepoint of implant retrieval. H Intraperitoneal glucose tolerance test conducted on healthy rats (n = 5), diabetic rats (n = 5), rats receiving a BEAM system (n = 4; measured on day 35), and rats receiving a cell encapsulation pouch without oxygen supplementary (n = 4; measured on day 35). Data are presented as mean ± SD. I Corresponding area under the curve for the groups in Fig. (H). Data are presented as mean ± SD. Statistical analyses were performed using one-way ANOVA. p = 0.0725 (diabetic rats vs. without oxygenation), p < 0.001 (with oxygenation vs. without oxygenation), p < 0.001 (heathy rats vs. without oxygenation), p = 0.9964 (heathy rats vs. with oxygenation).