## 4 Discussion  
A scaffold-free 3D culture method, Stemfit 3D(r), was used for the 3D culture of sPDLSCs, and was compared to a traditional 2D culture. The analyses of morphology, viability, osteogenic differentiation, and gene expression confirmed that the functions and characteristics of the sPDLSCs varied depending on the culture method. Stemfit 3D(r) uses a non-adhesive plate, which is 600 um in diameter, with a poly dimethylsiloxane-based concave micromold. Concave micromolds were used because they \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Gene Name** & **Fold Change** & **Description** & **Related Function** \\ \hline TAGLN & 15.7 & Transgenic & Cell differentiation \\ FBN2 & 15.3 & Fibrillin 2 & Extracellular matrix \\ LOX & 15.1 & Lysyl oxidase & Extracellular matrix \\ SEMA3D & 14.4 & Semaphorin 3D & Cell differentiation \\ LEP & 14.0 & Leptin & Cell differentiation, cell migration \\ COL6A6 & 13.6 & Collagen type VI alpha 6 & Extracellular matrix \\ MMP15 & 13.6 & Matrix metallopeptidase 15 & Extracellular matrix \\ CREB3L1 & 13.5 & cAMP-responsive element-binding & Cell differentiation \\  & & protein 3-like 1 & Cell differentiation \\ EFHD1 & 13.5 & EF-hand domain family member D1 & Cell differentiation \\ KRTAP1-5 & 13.4 & Keratin-associated protein 1-5 & Cell differentiation \\ ANLN & 13.3 & Anillin actin-binding protein & Cell cycle, cell differentiation, cell migration \\ HLA-DMA & 13.1 & Major histocompatibility complex, & Immune response \\  & & class II, DM alpha & Cell cycle, cell proliferation \\ MKI67 & 13.0 & Marker of proliferation Ki-67 & Cell death, cell differentiation \\ GDF6 & 12.9 & Growth differentiation factor 6 & Cell death, cell differentiation \\ ANKRD1 & 12.7 & Ankyrin repeat domain 1 & Cell differentiation \\ BCL2 & 12.6 & B-cell CLL/lymphoma 2 & Cell death, cell differentiation, cell \\  & & Regulating synaptic membrane & proliferation \\ RIMS1 & 12.5 & exocytosis 1 & Cell differentiation \\ ECM2 & 12.4 & Extracellular matrix protein 2 & Cell differentiation, extracellular matrix \\ TUBB2B & 12.2 & Tubulin beta 2B class IIb & Cell differentiation, cell migration \\ CLDN1 & 12.0 & Claudin 1 & Cell differentiation, immune response \\ AURKB & 11.7 & Aurora kinase B & Cell cycle \\ RTN1 & 11.6 & Reticulon 1 & Cell differentiation \\ BCAT1 & 11.6 & Branched chain amino acid & Cell cycle, cell proliferation \\ KIRREL3 & 11.5 & Kin of IRRE-like 3 (_Drosophila_) & Cell differentiation, cell migration \\ SLC4A5 & 11.2 & Solute carrier family 4 member 5 & Cell differentiation \\ MYC & 11.1 & v-Myc avian myelocytomatosis & proliferation, immune response \\  & & viral oncogene homolog & Angiogenesis, apoptotic process, cell death, \\ CYR61 & 11.0 & Cysteine-rich angiogenic inducer 61 & cell differentiation, cell migration, cell proliferation, extracellular matrix \\ CCBE1 & 11.0 & Collagen and calcium-binding EGF & Angiogenesis, extracellular matrix \\ TPM1 & 10.6 & Tropomyosin 1 (alpha) & Cell differentiation \\ CHAC1 & 10.5 & ChaC glutathione-specific & Apoptotic process, cell death, cell differentiation \\  & & gamma-glutamylcyclotransfarese 1 & Apgiogenesis, cell differentiation, cell migration, cell proliferation, \\ CTGF & 10.4 & Connective tissue growth factor & migration, cell proliferation, \\ NAV2 & 10.3 & Neuron navigator 2 & Extracellular matrix \\ ETV7 & 10.2 & ETS Variant 7 & Cell differentiation \\ CLEC3B & 10.1 & C-type lectin domain family 3 & Extracellular matrix \\  & & member B & Cell differentiation, cell migration, \\ MATN2 & 10.1 & Matrilin 2 & Cell differentiation, cell migration, \\  & & extracellular matrix \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Cont. accelerate cell aggregation compared to other methods (plane, cylindrical), and the cells form spheroids of uniform size that are easily harvested [2]. Moreover, 3D culture methods that use low-adhesive plates have lower long-term stability than other methods, because of the difficulty limiting the size of the spheroids [21].