Enzyme-immobilized hydrogels to create hypoxia for in vitro cancer cell culture

Camron S. Dawes, Heiko Konig, Chien Chi Lin

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

Hypoxia is a critical condition governing many aspects of cellular fate processes. The most common practice in hypoxic cell culture is to maintain cells in an incubator with controlled gas inlet (i.e., hypoxic chamber). Here, we describe the design and characterization of enzyme-immobilized hydrogels to create solution hypoxia under ambient conditions for in vitro cancer cell culture. Specifically, glucose oxidase (GOX) was acrylated and co-polymerized with poly(ethylene glycol)-diacrylate (PEGDA) through photopolymerization to form GOX-immobilized PEG-based hydrogels. We first evaluated the effect of soluble GOX on inducing solution hypoxia (O2 < 5%) and found that both unmodified and acrylated GOX could sustain hypoxia for at least 24 h even under ambient air condition with constant oxygen diffusion from the air-liquid interface. However, soluble GOX gradually lost its ability to sustain hypoxia after 24 h due to the loss of enzyme activity over time. On the other hand, GOX-immobilized hydrogels were able to create hypoxia within the hydrogel for at least 120 h, potentially due to enhanced protein stabilization by enzyme ‘PEGylation’ and immobilization. As a proof-of-concept, this GOX-immobilized hydrogel system was used to create hypoxia for in vitro culture of Molm14 (acute myeloid leukemia (AML) cell line) and Huh7 (hepatocellular carcinoma (HCC) cell line). Cells cultured in the presence of GOX-immobilized hydrogels remained viable for at least 24 h. The expression of hypoxia associated genes, including carbonic anhydrase 9 (CA9) and lysyl oxidase (LOX), were significantly upregulated in cells cultured with GOX-immobilized hydrogels. These results have demonstrated the potential of using enzyme-immobilized hydrogels to create hypoxic environment for in vitro cancer cell culture.

Original languageEnglish (US)
Pages (from-to)25-34
Number of pages10
JournalJournal of Biotechnology
Volume248
DOIs
StatePublished - Apr 20 2017

Fingerprint

Immobilized Enzymes
Glucose Oxidase
Glucose oxidase
Hydrogels
Cell culture
Enzymes
Cell Culture Techniques
Neoplasms
Hydrogel
Polyethylene glycols
Cultured Cells
Air
Cells
Carbonic anhydrase
Protein-Lysine 6-Oxidase
Hypoxia
In Vitro Techniques
Cell Line
Incubators
Carbonic Anhydrases

Keywords

  • Cancer
  • Enzyme immobilization
  • Glucose oxidase
  • Hydrogel
  • Hypoxia

ASJC Scopus subject areas

  • Biotechnology
  • Applied Microbiology and Biotechnology

Cite this

Enzyme-immobilized hydrogels to create hypoxia for in vitro cancer cell culture. / Dawes, Camron S.; Konig, Heiko; Lin, Chien Chi.

In: Journal of Biotechnology, Vol. 248, 20.04.2017, p. 25-34.

Research output: Contribution to journalArticle

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