Problem: The study of cells and their behavior is growing rapidly in drug discovery and disease research. This has created a huge demand for more efficient methods to culture cells. Traditional cell culturing, where cells are grown on two-dimensional plastic surfaces such as Petri dishes, flasks or microplates, is time-consuming and labor intensive. It also requires large capital investments and vast amounts of lab space. Automation has made throughput strides in recent years, but researchers still desire a more streamlined solution.

T24 (Human bladder carcinoma) cells grown on GEMS, fixed in paraformaldehyde, stained with Pico Green (Invitrogen) and nile red (Sigma) and imaged on a Zeiss 510 meta confocal microscope.

Solution: Global Cell Solutions (GCS), Charlottesville, VA, has developed a new cell culture substrate that enables growth in three dimensions while streamlining the process. The spherical Global Eukaryotic Microcarriers™ (GEMs) are made out of a hydrogel material with specialized protein coatings that encourage optimal cell attachment and expansion. The GEMs are embedded with magnetic particles, creating a vehicle with which to gently suspend and manipulate anchoragedependent cells. Cell culturing on these three-dimensional GEM surfaces yields more cells per volume than is possible with traditional two-dimensional formats and surfaces.

The GEM is non-autofluorescent and optically clear. Cell-based assays can be done while the cells are still attached to the GEM. Because the cells remain on the GEM, trypsin, which can diminish cell health and metabolic activity, is not required.

The GEMs can be coated with basement membrane or laminin to allow attachment and expansion of primary or stem cells. In addition to the different protein coatings, the GEM is porous, which allows 360° access to nutrients and ions. This leads to in vivo-like cell polarization required to study key diseases such as hypertension.

In order to maximize the application of the GEM technology, GCS has tapped Hamilton Company’s expertise in instruments and robotics. The collaborative result is the BioLevitator—a benchtop 3-D cell culture instrument that increases throughput and reduces costs compared to traditional methods. 3-D cell culture delivers efficient, high-density expansion that enables this powerful instrument to be packaged in a small footprint that fits on the lab bench. The BioLevitator holds up to four 50 mL cell culture tubes. A magnet suspends the GEMs while the tubes rotate to homogeneously suspend the microspheres. Impellers and other mechanical devices are not required. The substrate’s magnetic properties also enable the pelleting of cells for media changes. The process flow is streamlined, eliminating the need to passage cells or wait for them to re-adhere to the flask before phenotypic expression begins.

The BioLevitator eliminates traditional peripheral cell culture instruments, such as incubators and centrifuges, and minimizes manual handling. Each of the BioLevitator’s four hydrophobic, PTFE-filtered 50 mL cell culture tubes can produce cell growth equivalent to up to ten T75 flasks, depending on the cell line. The system features a user-friendly touch screen interface with real-time monitoring and control of environmental temperature and CO2 levels.

Cell lines can be preserved directly on the GEM, eliminating the need for harvesting prior to cryopreservation or reseeding post-thaw. Large batches of cells can be grown in the BioLevitator, dispensed into aliquots and frozen for use in downstream assays at a later date, reducing batch-to-batch variation. Human adipose stem cell, human umbilical vein and mouse smooth muscle cells are just a few examples of cell types that have been successfully cultured using the BioLevitator.

For more information, go to www.hamiltoncompany.com