Surface modification of fibroblasts with peroxiredoxin-1-loaded polymeric microparticles increases cell mobility, resistance to oxidative stress and collagen I production.

Modification of the cell surface with artificial nano- and microparticles (also termed "cellular backpacks") containing biologically active payloads usually enables drug targeting via harnessing intrinsic cell tropism to the sites of injury. In some cases, using cells as delivery vehicles leads to improved pharmacokinetics due to extended circulation time of cell-immobilized formulations. Another rationale for particle attachment to cells is augmentation of desirable cellular functions and cell proliferation in response to release of the particle contents. In this study, we conjugated poly(lactic-co-glycolic acid) (PLGA) microparticles loaded with multifunctional antioxidant enzyme peroxiredoxin-1 (Prx1) to the surface of fibroblasts. The obtained microparticles were uniform in size and demonstrated sustained protein release. We found that the released Prx1 maintains its signaling activity resulting in macrophage activation, as indicated by TNFα upregulation and increase in ROS generation. Functionalization of fibroblasts with PLGA/Prx1 microparticles via EDC/sulfo-NHS coupling reaction did not affect cell viability but increased cell migratory properties and collagen I production. Moreover, PLGA/Prx1 backpacks increased resistance of fibroblasts to oxidative stress and attenuated cell senescence. In summary, we have developed a novel approach of fibroblast modification to augment their biological properties, which can be desirable for wound repair, cosmetic dermatology, and tissue engineering.