Screening for Growth-Factor Combinations Enabling Synergistic Differentiation of Human MSC to Nucleus Pulposus Cell-Like Cells

Background: Multiple studies have examined the potential of growth factors (GF) to enable mesenchymal stromal cells (MSC) nucleus pulposus (NP) cell-like cell differentiation. Here we screened a wide range GF and combinations for supporting NP Methods: Human MSC were stimulated using 86 different TGF-β1, -2, -3, GDF5, -6, Wnt3a, -5a, -11, Shh. Differentiation potency was assessed by alcian blue assay marker expression (e.g., COL2A1, CD24, etc.). The top four GDF5/TGF-β1 further analyzed in 3D pellet cultures, on their ability similarly induce Results: Almost all showed enhance proteoglycan production assay. Subsequent qPCR analysis revealed TGF-β2/Wnt3a, TGF-β1/Wnt3a, TGF-β1/Wnt3a/GDF6, Wnt3a/GDF6 as most potent combinations. Although these supported expression, none significantly chondrogenic matrix production. Only resulted pellets with enhanced glycosaminoglycan content. Conclusion: suggested an optimal combination induction, although assessment vivo environment is required. Wnt3a proved promising monolayer-based differentiation, validation