These media do not contain hypoxanthine, aminopterin, thymidine, glutamine, or any other selective agents or antibiotics. These media are therefore fully customizable. Both ClonaCell™-CHO ACF and ClonaCell™-CHO CD are compatible with dihydrofolate reductase (DHFR) and glutamine synthetase (GS) selection.

The plating density for successful colony growth in protein-free medium needs to be higher than what is recommended for medium that contains protein. The optimal plating density should be determined empirically by plating several cell densities. For example, when re-cloning established cell lines, we recommend testing 200-1000 cells per 100 mm plate for ClonaCell™-CHO ACF and testing 2000-10000 cells per 100mm dish for ClonaCell™-CHO CD.

CHO cells selected in either ClonaCell™-CHO ACF or ClonaCell™-CHO CD semi-solid medium can be expanded in ClonaCell™-CHO CD Liquid medium.

Cloning efficiencies vary for different clones and cell lines. For optimal cloning efficiencies, cells should be in logarithmic phase prior to plating. If you have had previous experience with cloning in a chemically defined liquid medium, plating cell concentration that would result in ~100 clones may be used to plate in semi-solid medium (e.g. If plating at 1 cell/well in a 96-well plate results in 10 wells being positive for clones, plating 1000 cells per 100mm plate in semi-solid medium would be a good starting cell concentration to test). A minimum of three plating cell concentrations is recommended. If no work has been previously done with the specific cell line, we recommend a range of 25 000 - 100,000 cells per 100 mm dish for selection and cloning after transfection, and 2000 - 10,000 cells per 100 mm dish for subcloning. Additional optimization of cell concentrations may be necessary.