Abstract

Introduction

It is generally
considered that more biologically relevant in
vitro tumor models with improved functionality are required to advance
cancer drug development and that, three-dimensional (3D) cell culture in
hydrogels provides a more in vivo
-like environment for the cells compared to a traditional 2D monolayer culture.
Many of the ECMs commonly used for 3D culture are animal-derived gels which in
turn present the researcher with an additional set of   challenges.  such as, not being well defined in composition
and variation observed between production batches, resulting in inconsistent results.
An alternative to animal derived products is GrowDex®, a plant-based
hydrogel made from nanofibrillar cellulose (NFC), which has been shown to support
the 3D culture of variety of cells.

Inherent properties of GrowDex, such as shear
thinning and temperature stability, also make it an ideal hydrogel for use in
other applications in addition to 3D cell culture. With the rise in antibiotic
resistance new methods are needed to treat bacterial infections. Bacteriophage
therapy is one of the alternative options for fighting the antibiotic resistant
bacteria. Efficient treatment requires fast and reliable phage selection
process with possibility to transport phages between laboratories.

Results

3D culture of cancer cell lines including
hepatocellular carcinoma, glioblastoma, breast adenocarcinoma and breast ductal
carcinoma, colorectal adenocarcinoma, osteosarcoma, and prostate
adenocarcinoma, as well as culturing of patient-derived cells in GrowDex,
resulted in multicellular 3D structures. Screening of chemotherapeutic drug
libraries against the tumor organoids was successfully performed. The
shear-thinning property, temperature stability, and no need for cross-linking permit
its use with automated dispensing systems at ambient temperature. The grown 3D
cell structures can be recovered for detailed downstream analysis by use of
GrowDase™ cellulase enzyme treatment without impact to cell viability,
phenotype or function.

Bacteriophages against E. coli, St. aureus,
and P. aeruginosa were stored successfully in GrowDex using a 96-well plate format
and studied at various temperatures. The ready-to-use plates provided a
reliable way to transport the phages and offered a simple phage selection
screening platform for the clinician.

Conclusions

GrowDex has been shown to be an optimum matrix
for culture of in vitro 3D tumor
models and an ideal support matrix for bacteriophage applications. It is highly
biocompatible animal-free and ready-to-use, with shear-thinning properties and
temperature stability that facilitates easy dispensing. These properties make
GrowDex an attractive matrix for automated 3D cell-based assays e.g. in cancer drug
discovery and development, in addition to the storage, transportation, and
delivery of bacteriophages.