PEG Incorporated Polymeric Microcapsules for Intramyocardial Delivery of Stem Cells Genetically Modified by Baculovirus

The ability of mesenchymal stem cells to self-renew and differentiate into specialized cell lineages makes them promising tools for regenerative medicine. Local injection and use of scaffolds had been employed earlier to deliver these cells; yet, an optimal delivery system remains to be identified. Through the present work we developed a new microcapsule delivery system using polymeric alginatechitosan microcapsule coated with PEG (AC-PEG) to deliver human bone marrow derived stem cells (hBMSCs), genetically modified by recombinant baculoviruses (BacMGFP) carrying GFP as a reporter gene. The data indicates that the cells encapsulated in AC-PEG microcapsules can grow within the capsules. The capsules can also protect the cells against immune rejection. ACPEG microcapsules also had significantly higher mechanical and osmotic stability than commonly used AC microcapsules. The entrapped genetically modified cells showed transgene expression for at least two weeks. The encapsulated cells also retained their inherent potential to differentiate into multiple lineages. Thus, microencapsulated stem cells carrying therapeutic genes have immense potential to facilitate functional improvement in cellular heart failure therapy, although preclinical studies need to be done to establish their functional benefits on myocardial implantation.