Alginate-PLL cell encapsulation system Co-entrapping PLGA-microspheres for the continuous release of anti-inflammatory drugs

In spite of advances in cell microencapsulation technology in the past three decades, this approach still suffers from obstacles associated with its biocompatibility. We hypothesized that encapsulation system, which incorporates polymeric particles releasing anti-inflammatory drug in addition to the encapsulated cells, will result in improved biocompatibility, thus improving therapeutic efficacy. We have developed, optimized and studied a combined microencapsulation system in which Ibuprofen loaded PLGA microspheres (MS) are co-entrapped with cells. The combined system was developed and optimized in terms of Ibuprofen release profile, and the survival and proliferation of the co-encapsulated cells. The biocompatibility of the system was evaluated in vitro and in vivo. The developed system was shown to release Ibuprofen within two weeks, and support long-term cell viability. The combined system had improved the biocompatibility within the release period of Ibuprofen. All together, the co-encapsulation of anti-inflammatory loaded MS along with cells offers a clear advantage in the development of effective, long lasting cell based drug delivery systems. The choice of the anti-inflammatory agent, or combination of several anti-inflammatory agents needs to be carefully optimized, as well as their release profile to achieve long- term biocompatibility.