Cells grow on and around hollow fibers. ♦ Fiber geometry is optimized for both adherent and suspension cell types. ♦ Small molecules such as lactate, and glucose can easily cross the fiber. ♦ Large molecules such as mono clonal antibodies and proteins are retained and concentrated in the small volume of the extra capillary space.
FibraCel ® Disks A Solid Support Growth Material for Mammalian, Animal & Insect Cells Table 1 - Summary of cells commonly used successfully on FibraCel disks
Table 1 - Summary of cells commonly used successfully on FibraCel disks HybridomaAnchorage-DependentInsect DA4.4 123A 127A GAMMA 67-9-B 3T3, COS, Human Osteosarcoma MRC-5, BHK, VERO CHO, rCHO-tPA rCHO – Hep B Surface Antigen HEK 293, rHEK 293 rC127 – Hep B Surface Antigen Normal Human Fibroblasts Stroma Hepatocytes Tn-368 SF9 rSF9 Hi-5 FibraCel® Disks
Table 1 - Summary of cells commonly used successfully on FibraCel disks FibraCel® Disks Yes Autoclavable YesCytotoxicity tested YesBioburden tested YesEndotoxin tested 3 x 10 5 cells/mL final volumeRequired inoculum 6 mmDisk diameter 1200 cm 2 Surface Area per gram Specifications
Perfusion system - to provide fresh nutrient - to remove waste (especially toxic byproducts - mechanical signal
Fig. 1 Schematic diagram of the perfusion–bleeding culture system. The settler consists of a cylinder part and a cone part. Dimensions of the settler: height of the cylinder, 5.5 cm; height of the cone, 5.5 cm; internal diameter (i.d.) of the cylinder, 5 cm; i.d. of pipes number 1 and number 3, 3 mm; i.d. of pipe number 2, 5 mm. Pipe number 1 is connected to the settler in the middle part of the cylinder (Z.-Y. Wen and F. Chen, Applied Microbiology and Biotechnology, 57: 316 – 322, 2001)
S. Zhang, A. Handa-Corrigan,and R.E. Spier, BIOTECHNOLOGY AND BIOENGINEERING, VOL. 41, NO. 7, MARCH 25, 1993 Figure 1. Schematic diagram of the perfusion culture system.
Transport in a Grooved Perfusion Flat-Bed Bioreactor for Cell Therapy Applications Marc Horner, William M. Miller, J. M. Ottino, and E. Terry Papoutsakis Biotechnol Prog 1998 Sep-Oct;14(5):689-98
Figure 1. Model of the perfusion chamber, a flat-bed bioreactor in which a series of 190 grooves at the chamber bottom (shown in figure) retains cells in the presence of constant medium perfusion. This is a closed system, with no headspace when the lid is placed on top. Medium flows in the z-direction across the chamber. y and z represent the local coordinate system in a cavity.
A Microfabricated Array Bioreactor for Perfusion 3-D Liver Culture Mark J. Powers et. al Bioengineering & Biotechnology, 2002, 78:257-69
Hi Me Lo Hi Me Lo Cell Density Petri dishBioreactor Doubling time (days) 6 2 4 Fig. 6 Effects of Cell density on cell doubling time
Gas Exchange is Essential for Bioreactor Cultivation of Tissue Engineered Cartilage Bojana Obradovic, Rebecca L. Carrier, Gordana Vunjak- Novakovic, Lisa E. Freed Biotechnology and Bioengineering, 63: 197–205, 1999.
Figure 1. Model system. Isolated primary chondrocytes are seeded onto fibrous, biodegradable PGA scaffolds and cultured in vitro for 5 weeks in rotating bioreactors under different conditions of gas and medium exchange.
Group 1 (control) — regular medium replacement (50% v/v, 3 times per week), continuous gas exchange Group 2 (infrequent gassing) — regular medium replacement (50% v/v, 3 times a week), periodic gas exchange (3 times per week for 5 h, after medium replacement) Group 3 (no gassing) — regular medium replacement (50% v/v, 3 times per week), no gas exchange Group 4 (infrequent feeding) — Infrequent medium replacement (50% v/v, once per week), continuous gas exchange
Table II. Biochemical compositions of cell–polymer constructs.
Table III. Cell metabolism in cell–polymer constructs.
Comparison of Chondrogensis in Static and Perfused Bioreactor Culture David Pazzano,† Kathi A. Mercier,†, | John M. Moran,†,‡ Stephen S. Fong,†,‡ David D. DiBiasio,‡ Jill X. Rulfs,§ Sean S. Kohles, | and Lawrence J. Bonassar*,† Biotechnol Prog. 16(5):893-6 (2000)
Figure 1. Schematic representation of the perfusion bioreactor system assembly.
Figure 3. (A) Static sample at 2 weeks stained with safranin-O/fast green revealed light staining and no discernible orientation (400, bar ) 10 Ì m). (B) Bioreactor sample at 2 weeks stained with safranin-O/fast green (400, bar ) 10 Ì m). Intense staining was observed, as well as alignment of cells in the direction of media flow. A B
Cardiac Tissue Engineering: Cell Seeding, Cultivation Parameters, and Tissue Construct Characterization Rebecca L. Carrier, Maria Papadaki, Maria Rupnick, Frederick J. Schoen, Nenad Bursac,5 Robert Langer, Lisa E. Freed, Gordana Vunjak-Novakovic Biotechnol Bioeng. 64(5):580-9 (1999)
Figure 1. Effect of seeding vessel on the cellularity and metabolic activity of 3- day constructs. (a) DNA content ( m g/construct) (*) significantly greater than mixed flask group, p < 0.05 (n 4 4). (b) Medium LDH content (total U over 3 days of seeding) (*) significantly greater than all other groups, p < 0.05 (n 4 4). (c) Tetrazolium conversion (MTT assay OD units/mg DNA) (*) significantly greater than all other groups, p < 0.05 (n 4 4).
Figure 4. Cardiac-specific features: Constructs cultured for 1 week in a HARV (a, c, d) or a flask mixed at 50 rpm (b) and immunohistochemically labeled for (a) muscle desmin, (b) cardiac myosin, (c) cardiac troponin-T, and (d) sarcomeric tropomyosin. The arrow denotes a polymer fiber. (e) Transmission electron photomicrograph from a cardiac construct cultured for 1 week in a HARV demonstrating several adjacent cardiac myocytes with intercellular desmosome-like junctions (small arrows), myofibrils with sarcomeric organization highlighted by z lines (broad arrow), and compact mitochondria (open arrow). The nucleus of one cell is designated by the asterisk. Scale bars are 25 m m in a–d and 2 m m in e (original magnification 12,000).