Tunable osteogenic differentiation of hMPCs in tubular perfusion system bioreactor

Abstract

The use of bioreactors for bone tissue engineering has been widely investigated. While the benefits of shear stress on osteogenic differentiation are well known, the underlying effects of dynamic culture on subpopulations within a bioreactor are less evident. In this work, we explore the influence of applied flow in the tubular perfusion system (TPS) bioreactor on the osteogenic differentiation of human mesenchymal progenitor cells (hMPCs), specifically analyzing the effects of axial position along the growth chamber. TPS bioreactor experiments conducted with unidirectional flow demonstrated enhanced expression of osteogenic markers in cells cultured downstream from the inlet flow. We utilized computational fluid dynamic modeling to confirm uniform shear stress distribution on the surface of the scaffolds and along the length of the growth chamber. The concept of paracrine signaling between cell populations was validated with the use of alternating flow, which diminished the differences in osteogenic differentiation between cells cultured at the inlet and outlet of the growth chamber. After the addition of controlled release of bone morphogenic protein-2 (BMP-2) into the system, osteogenic differentiation among subpopulations along the growth chamber was augmented, yet remained homogenous. These results allow for greater understanding of axial bioreactor cultures, their microenvironment, and how well-established parameters of osteogenic differentiation affect bone tissue development. With this work, we have demonstrated the capability of tuning osteogenic differentiation of hMPCs through the application of fluid flow and the addition of exogenous growth factors. Such precise control allows for the culture of distinct subpopulation within one dynamic system for the use of complex engineered tissue constructs. Biotechnol. Bioeng. 2016;113: 1805-1813. © 2016 Wiley Periodicals, Inc.

Fabrication and evaluation of 3D printed BCP scaffolds reinforced with ZrO2 for bone tissue applications

“…This allowed for confluency and proliferation of hMSCs on the scaffolds. Cell‐seeded scaffolds were then osteogenically differentiated for 21 days using hMSC growth media supplemented with 100 nM dexamethasone, 10 mM β‐glycerophosphate, and 173 mM ascorbic acid as previously described in either static or dynamic conditions using the TPS bioreactor (Nguyen, Ko, & Fishe, ; Nguyen, Ko, Moriarty, Etheridge, & Fisher, ; Yeatts & Fisher, ; Yeatts, Gordon, & Fisher, ). Static scaffolds were cultured in 6‐well plates (Corning, Inc., Corning, NY) and 5 ml of osteogenic media, while scaffolds under dynamic conditions were cultured under 3 ml shear flow in the TPS bioreactor.…”

Hydroxyapatite‐doped alginate beads as scaffolds for the osteoblastic differentiation of mesenchymal stem cells

“…hMSCs were encapsulated in scaffolds as described in “Preparation of alginate beads and hMSC encapsulation” section and cultured in 6 well plates for 7 days to examine the expression osteogenic markers alkaline phosphatase (ALP) and bone morphogenetic protein 2 (BMP‐2). These parameters were selected so that results could be considered in context of other hMSC differentiation studies …”

“…These parameters were selected so that results could be considered in context of other hMSC differentiation studies. 17 Expression of the osteogenic genes ALP and BMP-2 was evaluated from cells cultured in both the 50:50 and 5:95 scaffolds using quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). Each experimental group consisted of hMSCs isolated from n 5 40 scaffolds.…”

Collagen hydrogel scaffold promotes mesenchymal stem cell and endothelial cell coculture for bone tissue engineering

“…Dynamic culture conditions can be created in a perfusion bioreactor that mimics in vivo conditions. We have previously demonstrated the benefits of the tubular perfusion system (TPS) bioreactor on osteogenic differentiation of hMSCs due to the applied shear flow and the increased oxygen and nutrient supply to the cultured cells . Although these systems have been utilized to create bone tissue constructs of large sizes, the leap from in vitro bench top applications to clinical reality will require the presence of ECs within the construct to allow for the establishment of preexisting vasculature.…”