Phenotype and Viability of MLO-Y4 Cells Is Maintained by TGFβ₃ in a Serum-Dependent Manner within a 3D-Co-Culture with MG-63 Cells

TY - JOUR

T1 - Phenotype and Viability of MLO-Y4 Cells Is Maintained by TGFβ₃ in a Serum-Dependent Manner within a 3D-Co-Culture with MG-63 Cells

AU - Jähn, Katharina

AU - Mason, Deborah J.

AU - Ralphs, Jim R.

AU - Evans, Bronwen A.J.

AU - Archer, Charles W.

AU - Richards, R. Geoff

AU - Stoddart, Martin J.

PY - 2018/6/30

Y1 - 2018/6/30

N2 - The osteocyte network inside the bone matrix is of functional importance and osteocyte cell death is a characteristic feature of pathological bone diseases. Osteocytes have emerged as key regulators of bone tissue maintenance, yet maintaining their phenotype during in vitro culture remains challenging. A 3D co-culture system for osteocytes with osteoblasts was recently presented, enabling the determination of more physiological effects of growth factors on cells in vitro. MLO-Y4 cells were embedded within a type I collagen gel and cultured in the presence of surface MG-63 cells. Co-culture was performed in the presence or absence of TGFβ₃. Gene expression by quantitative PCR, protein expression by fluorescent immunohistochemistry and cell viability tests were performed. The 3D co-culture induced cell differentiation of MG-63 cells seen by increased type I collagen and osteocalcin mRNA expression. TGFβ₃ maintained osteocyte differentiation of MLO-Y4 cells during co-culture as determined by stable E11 and osteocalcin mRNA expression till day 4. Interestingly, most of the effects of TGFβ₃ on co-cultured cells were serum-dependent. Also, TGFβ₃ reduced cell death of 3D co-cultured MLO-Y4 cells in a serum-dependent manner. This study shows that 3D co-culture upregulates differentiation of MG-63 cells to a more mature osteoblast-like phenotype; while the addition of TGFβ₃ maintained the characteristic MLO-Y4 osteocyte-like phenotype and viability in a serum-dependent manner.

AB - The osteocyte network inside the bone matrix is of functional importance and osteocyte cell death is a characteristic feature of pathological bone diseases. Osteocytes have emerged as key regulators of bone tissue maintenance, yet maintaining their phenotype during in vitro culture remains challenging. A 3D co-culture system for osteocytes with osteoblasts was recently presented, enabling the determination of more physiological effects of growth factors on cells in vitro. MLO-Y4 cells were embedded within a type I collagen gel and cultured in the presence of surface MG-63 cells. Co-culture was performed in the presence or absence of TGFβ₃. Gene expression by quantitative PCR, protein expression by fluorescent immunohistochemistry and cell viability tests were performed. The 3D co-culture induced cell differentiation of MG-63 cells seen by increased type I collagen and osteocalcin mRNA expression. TGFβ₃ maintained osteocyte differentiation of MLO-Y4 cells during co-culture as determined by stable E11 and osteocalcin mRNA expression till day 4. Interestingly, most of the effects of TGFβ₃ on co-cultured cells were serum-dependent. Also, TGFβ₃ reduced cell death of 3D co-cultured MLO-Y4 cells in a serum-dependent manner. This study shows that 3D co-culture upregulates differentiation of MG-63 cells to a more mature osteoblast-like phenotype; while the addition of TGFβ₃ maintained the characteristic MLO-Y4 osteocyte-like phenotype and viability in a serum-dependent manner.

U2 - doi: 10.3390/ijms19071932

DO - doi: 10.3390/ijms19071932

M3 - SCORING: Journal article

VL - 19

SP - 1

EP - 11

JO - INT J MOL SCI

JF - INT J MOL SCI

SN - 1661-6596

IS - 7

ER -