@article{kumar_lau_starly_2017, title={Human Mesenchymal Stem Cells Expansion on Three-Dimensional (3D) Printed Poly-Styrene (PS) Scaffolds in a Perfusion Bioreactor}, volume={65}, ISSN={["2212-8271"]}, DOI={10.1016/j.procir.2017.04.012}, abstractNote={In this study, we present a novel approach of expanding Adipose derived hMSCs (human Mesenchymal Stem Cells) seeded on 3D printed Poly-Styrene (PS) scaffolds within a perfusion based cell expansion bioreactor. 3D printed PS scaffolds inoculated with adipose derived hMSCs were cultured statically for 9 days in 2D for assuring the viability and proliferation expansion of hMSCs on PS scaffolds. Thereafter, a batch of pre-seeded scaffolds were dynamically cultured inside a perfusion based bioreactor system for 8 days to assess the expansion of hMSCs on the PS scaffolds. As compared to static 3D culture (control), the 3D perfusion based system resulted in comparable fold-expansion and viability. Osteogenic and Adipogenic differentiation potential of the harvested cells were evaluated to assess if the stem cells retained their stem cell properties at the end of the expansion step.}, journal={3RD CIRP CONFERENCE ON BIOMANUFACTURING}, author={Kumar, Arun and Lau, Wing and Starly, Binil}, year={2017}, pages={115–120} }
 @inproceedings{kumar_starly_2016, title={Modeling human mesenchymal stem cell expansion in vertical wheel bioreactors using lactate production rate in regenerative medicine biomanufacturing}, DOI={10.1115/msec2016-8787}, abstractNote={Stem cells are critical components of regenerative medicine therapy. However, the therapy will require millions to billions of therapeutic stem cells. To address the need, we have recently cultured stem cells in 3D microgels and used them as a vehicle for cell expansion within a low shear stress rotating wheel type bioreactor within a 500ml volumetric setting. This study specifically highlights the cell encapsulation in microbead process, harvesting and operation of microbeads within a dynamic bioreactor environment. We have specifically encapsulated stem cells (human adipose derived) into microbeads prepared from alginate hydrogels via an electrostatic jetting process. This study highlights the effect of fabrication process parameters on end-point biological quality measures such as stem cell count and viability. We were able to maintain a >80% viability during the 21 day static culture period. We have also measured the concentration of metabolites produced during the expansion, specifically lactate production measured during specific time points within culture inside the rotating wheel bioreactor Future work will need to address predicting yields in higher volume settings, efficiency of harvest and a more detailed description of the hydrodynamics affecting stem cell growth.}, booktitle={Proceedings of the ASME 11th International Manufacturing Science and Engineering Conference, 2016, vol 2}, author={Kumar, A. and Starly, Binil}, year={2016} }
 @article{kumar_starly_2015, title={Large scale industrialized cell expansion: producing the critical raw material for biofabrication processes}, volume={7}, ISSN={["1758-5090"]}, DOI={10.1088/1758-5090/7/4/044103}, abstractNote={Cellular biomanufacturing technologies are a critical link to the successful application of cell and scaffold based regenerative therapies, organs-on-chip devices, disease models and any products with living cells contained in them. How do we achieve production level quantities of the key ingredient—‘the living cells’ for all biofabrication processes, including bioprinting and biopatterning? We review key cell expansion based bioreactor operating principles and how 3D culture will play an important role in achieving production quantities of billions to even trillions of anchorage dependent cells. Furthermore, we highlight some of the challenges in the field of cellular biomanufacturing that must be addressed to achieve desired cellular yields while adhering to the key pillars of good manufacturing practices—safety, purity, stability, potency and identity. Biofabrication technologies are uniquely positioned to provide improved 3D culture surfaces for the industrialized production of living cells.}, number={4}, journal={BIOFABRICATION}, author={Kumar, Arun and Starly, Binil}, year={2015}, month={Dec} }