Composite scaffolds for osteochondral repair obtained by combination of additive manufacturing, leaching processes and hMSC-CM functionalization

Abstract

A b s t r a c tArticular repair is a relevant and challenging area for the emerging fields of tissue engineering and biofabrication. The need of significant gradients of properties, for the promotion of osteochondral repair, has led to the develop ment of several families of composite biomaterials and scaffolds, using different effective approaches, although a perfect solution has not yet been found. In this study we present the design, modeling, rapid manufacturing and in vitro testing of a composite scaffold aimed at osteochondral repair. The presented composite scaffold stands out for having a functional gradient of density and stiffness in the bony phase, obtained in titanium by means of computer aided design combined with additive manufacture using selective laser sintering. The chondral phase is obtained by sugar leaching, using a PDMS matrix and sugar as porogen, and is joined to the bony phase during the polymerization of PDMS, therefore avoiding the use of supporting adhesives or additional intermediate layers. The mechanical performance of the construct is biomimetic and the stiffness values of the bony and chondral phases can be tuned to the desired applications, by means of controlled modifications of different parameters. A human mesenchymal stem cell (h MSC) conditioned medium (CM) is used for improving scaffold response. Cell culture results provide relevant information regarding the viability of the composite scaffolds used.

3D Printed Structures Filled with Carbon Fibers and Functionalized with Mesenchymal Stem Cell Conditioned Media as In Vitro Cell Niches for Promoting Chondrogenesis

“…The composite scaffolds were individually placed in 25 mL Falcon culture tubes(see Figure 3 ) and successively treated with 2 mL of (i) 95% ethanol, for a duration of 30 min and two times, to dissociate the bundle of carbon fibers into parallel carbon fibrils, with an average cross section of 4μm, by removing the holding resin used during fabric texturing; (ii) PBS wash; (iii) 2M HCl attack for 24 h for the acid activation of surfaces; (iv) PBS wash until neutralization; (v) surface coating CM-hMSCs for 24 h in cell incubator; (vi) removal of hMSC-CM and 10 5 hMSCs seeding drop by drop. After 30 min in a cell incubator, the composite niches were exposed to a growth medium of DMEM-LG–10%FBS and to a chondrogenic differentiation medium, with composition described in [ 23 , 24 ], for a duration of seven days, changing the media twice a day.…”

Research on the Methods for the Mass Production of Multi-Scale Organs-On-Chips

“…Once the conditioned medium is prepared, the multi-organ-on-chip biomedical microdevice is sterilized, washed and surface coated with the CM-hMSCs during 24 h in cell incubator, which is removed, just before seeding the microsystem with 10 3 hMSCs drop by drop and using the six chamber inlets of the micro-injected polymeric replica used for the validation. Summarizing, the process follows previous research with some slight modifications [23,24]. The results from cell motility and colonization of the microsystems were determined by staining with crystal violet and by optical microscopy and are discussed in the following section.…”

A review on gradient hydrogel/fiber scaffolds for osteochondral regeneration

“…To date, manifold metal–polymer and ceramic‐polymer composites have been employed to restore osteochondral lesions. Although these composites can bring together the stiffness of metals or ceramics for the osseous phase and the viscoelasticity of polymers for the cartilaginous part (Lantada, Iniesta, & García‐Ruiz, ), they still confront some shortcomings. First and foremost, the scaffolds did not completely imitate the native matrix of osteochondral tissues as they match mechanically but not architecturally and functionally with osteochondral interfaces.…”