Clinical islet transplantation (CIT) is accompanied by immunosuppressive therapy to avoid rejection of allogeneic donor cells. The life-long intake of these drugs increases the risks of infections, of certain types of cancers and limits the treatment of type 1 diabetes with CIT to patients suffering from severe brittle diabetes and already receive immunosuppressive therapy. In this study, we develop a macro-encapsulation device based on thin microwell membranes, able to keep the islets separated, to shield them from the host immune cells without compromising their endocrine function and survival.
The membranes were fabricated using by phase separation micromolding. The membrane porosity was optimized to allow efficient glucose and insulin transport but to prevent cell infiltration providing immuno-protection. Human islets, were encapsulated within the membrane and constructs were cultured 7 days. In vitro studies show that the human islets are viable and respond to varying glucose concentration over a 1 week period.
Reference: Skrzypek, et al., (2017) Scientific Reports 7: 9186.