RGD-Dendrimer-Poly(L-lactic) Acid Nanopatterned Substrates for the Early Chondrogenesis of Human Mesenchymal Stromal Cells Derived from Osteoarthritic and Healthy Donors

Abstract

Aiming to address a stable chondrogenesis derived from mesenchymal stromal cells (MSCs) to be applied in cartilage repair strategies at the onset of osteoarthritis (OA), we analyzed the effect of arginine–glycine–aspartate (RGD) density on cell condensation that occurs during the initial phase of chondrogenesis. For this, we seeded MSC-derived from OA and healthy (H) donors in RGD-dendrimer-poly(L-lactic) acid (PLLA) nanopatterned substrates (RGD concentrations of 4 × 10−9, 10−8, 2.5 × 10−8, and 10−2 w/w), during three days and compared to a cell pellet conventional three-dimensional culture system. Molecular gene expression (collagens type-I and II–COL1A1 and COL2A1, tenascin-TNC, sex determining region Y-box9-SOX9, and gap junction protein alpha 1–GJA1) was determined as well as the cell aggregates and pellet size, collagen type-II and connexin 43 proteins synthesis. This study showed that RGD-tailored first generation dendrimer (RGD-Cys-D1) PLLA nanopatterned substrates supported the formation of pre-chondrogenic condensates from OA- and H-derived human bone marrow-MSCs with enhanced chondrogenesis regarding the cell pellet conventional system (presence of collagen type-II and connexin 43, both at the gene and protein level). A RGD-density dependent trend was observed for aggregates size, in concordance with previous studies. Moreover, the nanopatterns’ had a higher effect on OA-derived MSC morphology, leading to the formation of bigger and more compact aggregates with improved expression of early chondrogenic markers.

Nanoscale ligand density modulates gap junction intercellular communication of cell condensates during chondrogenesis

“…Therefore, the S90 configuration, in which 90% of the surface area contains adhesion sites separated less than 70 nm, could be emulating the native disposition of integrin binding sites in the ECM of developing cartilage, thus favoring mesenchymal cell condensation and differentiation. The results obtained have an immediate application to cartilage in vitro development [36,72], for which we are already producing cell constructs to be implanted in cartilage lesions of animal models, but they are also extensible to the study of other biological processes in which active ECM remodelling and thus, changes in the adhesion requirements and intercellular communication play an active role, such as in cancer progression [73].…”

“…By tailoring the nanopattern configuration of the cell-adhesive motif RGD, we exerted control over the architecture and function of a complex dynamic biological system. The results have an immediate application to cartilage in vitro engineering [30,54], but they are also extensible to the study of other biological processes in which active ECM remodelling and thus, changes in the adhesion requirements and intercellular communication play an active role, such as in cancer progression [55].…”

“…The results obtained have an immediate application to cartilage in vitro development [36,72], for which we are already producing cell constructs to be implanted in cartilage lesions of animal models, but they are also extensible to the study of other biological processes in which active ECM remodelling and thus, changes in the adhesion requirements and intercellular communication play an active role, such as in cancer progression [73].…”

MSN based biointerfaces to advance knowledge on ligand-stem cell interaction

“…In another study, RGD-dendrimer-based nanopatterns on poly(lactic acid) (PLLA) were developed by immersing PLLA substrates in aqueous solutions of an RGD-tailored dendrimer (RGD-Cys-D1) [88]. RGD surface density was tuned by using a range of dendrimer concentrations (4 × 10 -9 -10 -2 (% w/w) PLLA nanopatterned substrates, using a three-dimensional (3D) pellet culture system as reference model [121]. It was shown that RGD-Cys-D1 PLLA nanopatterned substrates could enhance the adhesion and formation of prechondrogenic condensates from OA-and H-derived BM-MSCs compared to the 3D cell pellet culture reference model.…”