TY  - JOUR
AU  - Sobel, Douglas O.
AU  - Parmar, Keerat
PY  - 2026
DA  - 2026/04/14
TI  - Development of New Macroencapsulating Planar Devices to Inhibit Allorejection of Islet Transformed Cells
JO  - OBM Transplantation
SP  - 269
VL  - 10
IS  - 02
AB  - Subcutaneous transplantation of islets into small-pore macroencapsulation devices that prevent immune cell passage can inhibit allorejection in rodents. However, there are no reports of euglycemia in humans using this technology. This report further develops these macroencapsulation devices. We compared the ability of macroencapsulation transplant devices containing transformed mouse islet cells (MIN-6) with varying polymer membranes, pore sizes, and hydrophilicity to inhibit allorejection and maintain glycemic control in diabetic mice. We found that 10 μm pore planar polytetrafluoroethylene (PTFE) devices do not inhibit allorejection; 1-2 μm pore devices allow only partial protection; and 0.4 μm devices prevent long-term allorejection. A more hydrophilic PTFE membrane (PTFE-HP) improves device function. Devices constructed with nylon and, secondly, PTFE-HP membranes serve as transplant devices better than those constructed with polyvinylidene fluoride (PVDF), fluorinated ethylene propylene (FEP), ethylenetetrafluoroethylene (ETFE), or polyethersulfone (PES), and result in a lower fibrotic response. Allo-presensitized mice are equally protected from allorejection with 0.4 μm pore PTFE-HP transplant devices as non-presensitized mice. Our layered membrane macroencapsulation device is as effective as a single planar device in inhibiting allorejection. Nylon and, secondly, hydrophilic PTFE macroencapsulation transplant devices with 0.4 μm pores robustly prevent allotransplant rejection compared with all membranes tested and induce the least fibrosis. Future studies with nylon membranes are warranted. A multilayered device is described that reduces the skin surface requirement and increases potential islet load. A transplant model using MIN-6 cells is feasible for studying such devices to prevent allorejection.
SN  - 2577-5820
UR  - https://doi.org/10.21926/obm.transplant.2602269
DO  - 10.21926/obm.transplant.2602269
ID  - Sobel2026
ER  -