Researchers from IRCCS Istituto Ortopedico Rizzoli and Indian Institute of Technology, Delhi (IIT) used their REGENHU bioprinters to fabricate an in vitro phenotypically stable engineered articular cartilage by embedding human bone marrow-derived stromal cells (hMSCs) in a cell-laden silk fibroin–gelatin (SF-G) bioink.
The bioprinted constructs allowed the in vitro study of chondrogenic signaling pathways, as well as the role of TGF-β signaling.
This was achieved by means of a thorough proteomic analysis and evaluation of the protein expression related to cartilage-specific signaling pathways. This knowledge could provide essential insights in understanding how the bioprinted construct can create an active and instructive microenvironment for cells to promote cartilage-specific tissue regeneration.

Discover more here : https://link.springer.com/article/10.1557/s43578-021-00230-5


Major limitation of 3D bioprinting is the poor understanding of the role of bioink in modulating molecular signaling pathways. Phenotypically stable engineered articular cartilage was fabricated using silk fibroin–gelatin (SF-G) bioink and progenitor cells or mature articular chondrocytes. In the current study, role of SF-G bioink in modulating in vitro chondrogenic signaling pathways in human bone marrow-derived stromal cells (hMSCs) is elucidated. The interaction between SF-G bioink and hMSCs augmented several chondrogenic pathways, including Wnt, HIF-1, and Notch. We explored the debatable role of TGF-β signaling, by assessing the differential protein expression by hMSCs-laden bioprinted constructs in the presence and absence of TGF-β3. hMSCs-laden bioprinted constructs contained a large percentage of collagen type II and Filamin-B, typical to the native articular cartilage. Hypertrophy markers were not identified following TGF-β3 addition. This is first detailed proteomics analysis to identify articular cartilage-specific pathways in SF-G-based 3D bioprinted construct.