Hollow Fiber Bioreactor (hollow + fiber_bioreactor)

Distribution by Scientific Domains


Selected Abstracts


Hemoglobin regulates the metabolic and synthetic function of rat insulinoma cells cultured in a hollow fiber bioreactor

BIOTECHNOLOGY & BIOENGINEERING, Issue 3 2010
Sharon I. Gundersen
Abstract Pancreatic islet transplantation continues to benefit patients with type 1 diabetes by normalizing glucose metabolism and improving other complications of diabetes. However, islet transplantation therapy is limited by the inadequate availability of pancreatic islets. In order to address this concern, this work investigated the expansion of rat insulinoma cells (INS-1) and their ability to generate insulin in a hollow fiber bioreactor (HFB). The long-term goal of this project is to develop a bioartificial pancreas. HFBs were incubated at two different oxygenation conditions (10% and 19% O2) to determine the best scenario for O2 transport to cultured cells. Also, bovine hemoglobin (BvHb) was supplemented in the cell culture media of the HFBs in order to increase O2 transport under both oxygenation conditions. Our results show that INS-1 cells expanded under all oxygenation conditions after 2 weeks of culture, with a slightly higher cell expansion under normoxic oxygenation (19% O2) for both control HFBs and BvHb HFBs. In addition, cellular insulin production remained steady throughout the study for normoxic control HFBs and BvHb HFBs, while it increased under hypoxic oxygenation (10% O2) for both types of HFBs but to different extents. Under the two different oxygenation conditions, cellular insulin production was more uniform with time in BvHb HFBs versus control HFBs. These results, along with qRT-PCR analysis, suggest a possible dysregulation of the insulin-signaling pathway under hypoxic culture conditions. In conclusion, the HFB culture system is an environment capable of expanding insulinomas while maintaining their viability and insulin production capabilities. Biotechnol. Bioeng. 2010;107: 582,592. © 2010 Wiley Periodicals, Inc. [source]


Perfluorocarbon facilitated O2 transport in a hepatic hollow fiber bioreactor

BIOTECHNOLOGY PROGRESS, Issue 5 2009
Guo Chen
Abstract A mathematical model describing O2 transport in a hepatic hollow fiber (HF) bioreactor supplemented with perfluorocarbons (PFCs) in the circulating cell culture media was developed to explore the potential of PFCs in properly oxygenating a bioartificial liver assist device (BLAD). The 2-dimensional model is based on the geometry of a commercial HF bioreactor operated under steady-state conditions. The O2 transport model considers fluid motion of a homogeneous mixture of cell culture media and PFCs, and mass transport of dissolved O2 in a single HF. Each HF consists of three distinct regions: (1) the lumen (conducts the homogeneous mixture of cell culture media and PFCs), (2) the membrane (physically separates the lumen from the extracapillary space (ECS), and (3) the ECS (hepatic cells reside in this compartment). In a single HF, dissolved O2 is predominantly transported in the lumen via convection in the axial direction and via diffusion in the radial direction through the membrane and ECS. The resulting transport equations are solved using the finite element method. The calculated O2 transfer flux showed that supplementation of the cell culture media with PFCs can significantly enhance O2 transport to the ECS of the HF when compared with a control with no PFC supplementation. Moreover, the O2 distribution and subsequent analysis of ECS zonation demonstrate that limited in vivo-like O2 gradients can be recapitulated with proper selection of the operational settings of the HF bioreactor. Taken together, this model can also be used to optimize the operating conditions for future BLAD development that aim to fully recapitulate the liver's varied functions. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 [source]


HBOCs and PFCs synergistically oxygenate hollow fiber bioreactors

BIOTECHNOLOGY & BIOENGINEERING, Issue 3 2010
Article first published online: 23 DEC 200
No abstract is available for this article. [source]


Mixtures of hemoglobin-based oxygen carriers and perfluorocarbons exhibit a synergistic effect in oxygenating hepatic hollow fiber bioreactors

BIOTECHNOLOGY & BIOENGINEERING, Issue 3 2010
Guo Chen
Abstract Hepatic hollow fiber (HF) bioreactors are being developed for use as bioartificial liver assist devices (BLADs). In general, BLADs suffer from O2 limited transport, which reduces their performance. This modeling study seeks to investigate if O2 carrying solutions consisting of mixtures of hemoglobin-based oxygen carriers (HBOCs) and perfluorocarbons (PFCs) can enhance O2 transport to hepatocytes cultured in the extra capillary space (ECS) of HF bioreactors. We simulated supplementing the circulating cell culture media stream of the HF bioreactor with a mixture containing these two types of oxygen carriers (HBOCs and PFCs). A mathematical model was developed based on the dimensions and physical characteristics of a commercial HF bioreactor. The resulting set of partial differential equations, which describes fluid transport; as well as, mass transport of dissolved O2 in the pseudo-homogeneous PFC/water phase and oxygenated HBOC, was solved to yield the O2 concentration field in the three HF domains (lumen, membrane and ECS). Our results show that mixtures of HBOC and PFC display a synergistic effect in oxygenating the ECS. Therefore, the presence of both HBOC and PFC in the circulating cell culture media dramatically improves transport of O2 to cultured hepatocytes. Moreover, the in vivo O2 spectrum in a liver sinusoid can be recapitulated by supplementing the HF bioreactor with a mixture of HBOCs and PFCs at an inlet pO2 of 80,mmHg. Therefore, we expect that PFC-based oxygen carriers will be more efficient at transporting O2 at higher O2 levels (e.g., at an inlet pO2 of 760,mmHg, which corresponds to pure O2 in equilibrium with aqueous cell culture media at 1,atm). Biotechnol. Bioeng. 2010; 105: 534,542. © 2009 Wiley Periodicals, Inc. [source]