The use of dinoflagellate bioluminescence to characterize cell stimulation in bioreactors.
Bioluminescent dinoflagellates are flow-sensitive marine organisms that produce light emission almost instantaneously upon stimulation by fluid shear in a shear stress dose-dependent manner. In the present study we tested the hypothesis that monitoring bioluminescence by suspended dinoflagellates can be used as a tool to characterize cellular response to hydrodynamic forces in agitated bioreactors. Specific studies were performed to determine: (1) impeller configurations with minimum cell activation, (2) correlations of cellular response and an integrated shear factor, and (3) the effect of rapid acceleration in agitation. Results indicated that (1) at a volumetric mass transfer coefficient of 3 x 10(-4) s(-1), marine impeller configurations were less stimulatory than Rushton configurations, (2) bioluminescence response and a modified volumetric integrated shear factor had an excellent correlation, and (3) rapid acceleration in agitation was highly stimulatory, suggesting a profound effect of temporal gradients in shear in increasing cell stimulation. By using bioluminescence stimulation as an indicator of agitation-induced cell stimulation and/or damage in microcarrier cultures, the present study allows for the verification of hypotheses and development of novel mechanisms of cell damage in bioreactors.
Chen
Antony K
AK
Department of Bioengineering, University of California-San Diego, La Jolla, California, USA.
Latz
Michael I
MI
Frangos
John A
JA
D000054:Acceleration; D000818:Animals; D019149:Bioreactors / Q000382:microbiology*; D015374:Biosensing Techniques; D004141:Dinoflagellida / Q000254:growth & development / Q000502:physiology*; D049449:Luminescence; D040542:Mechanotransduction, Cellular / Q000502:physiology*; D009038:Motion; D010812:Physical Stimulation / Q000379:methods*; D012212:Rheology / Q000379:methods*; D033081:Shear Strength; D013314:Stress, Mechanical