Photocrosslinkable natural based hydrogel matrices have received great interest for tissue engineering strategies, especially because they provide versatile systems that can be potentially used in diverse applications. Nevertheless, to engineer complex tissues and/or tissue interfaces, it is necessary to develop systems that can accommodate various functionalities. Such systems could also benefit from the possibility of being remotely controlled and/or further manipulated ex vivo.
This work reports on the development of a photocrosslinkable magnetic responsive hydrogel based on a methacrylated chondroitin sulfate (met-CS) matrix enriched with platelet lysate (PL), envisioning the generation of tunable hydrogel building blocks to engineer tissue interfaces, such as tendon-bone. To provide magnetic responsiveness, magnetic nanoparticles (MNPs) coated with met-CS (met-CS MNPs) were produced to enable their linkage to the hydrogel matrix. The produced met-CS MNPs were characterized and subsequently incorporated in PL enriched met-CS hydrogel matrices. The actuation of an external magnetic field (EMF) to modulate the properties of the system was then investigated. The application of an EMF was shown to modulate the swelling, degradation and release of growth factors naturally present in the PL. Moreover, the effect of EMF in hydrogels laden with either pre-osteoblasts differentiated from human adipose derived stem cells (pre-Ost) or human tendon cells (hTDCs), was assessed in single and co-culture systems. Both hTDCs and pre-Ost cells were able to proliferate, colonize and express tendon and bone related markers in the developed hydrogels. Moreover EMF seems to impact cell morphology and the synthesis of a tendon- and bone- like ECM, whose effect is highlighted in co-culture systems. Together, these results suggest that developed hydrogel represents a potential cell laden system for tissue engineering in which the properties can be externally modulated through EMF stimulation.