Cell selective chitosan microparticles as injectable cell carriers for tissue regeneration

The detection, isolation and sorting of cells holds an important role in cell therapy

and regenerative medicine. Also, injectable systems have been explored for tissue

regeneration in vivo, because it allows repairing complex shaped tissue defects

through minimally invasive surgical procedures. Here we report the development of

chitosan microparticles with a size of 115.8μm able to capture and expand a specific

cell type that can also be regarded as an injectable biomaterial. Monoclonal

antibodies against cell surface antigens specific to endothelial cells and stem cells

were immobilized on the surface of the microparticles. Experimental results showed

that particles bioconjugated with specific antibodies provide suitable surfaces to

capture a target cell type and subsequent expansion of the captured cells. Primarily

designed for an application in tissue engineering, three main challenges are

accomplished with the herein presented microparticles: separation, scale-up

expansion of specific cell type and successful use as an injectable system to form

small tissue constructs in situ.