Cells grown in liquid medium may appear to grow more rapidly than in methylcellulose-based medium. This is often due to the presence of a few rapidly growing clones that multiply quickly and become abundant in liquid culture, overgrowing clones that grow more slowly. In methylcellulose cultures, the rapidly growing cells remain in close proximity to each other, resulting in large colonies, each derived from a single fusion or transfection product. The large clones don't overgrow smaller, slower growing colonies, which can be separately isolated.

We recommend thawing the medium overnight in a refrigerator at 4°C and mixing well.

We recommend using a 12 mL syringe with a 16 gauge needle attached (blunt end needles are recommended for safety purposes). Do not dispense the semi-solid media/cell mixture using serological pipettes as the media will stick to the pipette walls, resulting in inaccurate dispensed volumes and loss of cells.

"Runny" methylcellulose could be a result of improper handling. Diluting the methylcellulose with too much liquid medium, or insufficient mixing before use, will result in methylcellulose with altered viscosity. Excessive condensation on the inside of the cell culture dish lid can result in water dripping onto the cultures, lowering viscosity. Additionally, bumping, shaking or other sudden movement of the culture may also disrupt the colonies. Note: methylcellulose is less viscous at room temperature than at 37°C.

We recommend 50-150 colonies per plate. As it is difficult to anticipate the numbers of colonies after a fusion or transfection, we recommend plating at three different densities to increase the likelihood of achieving a plating density of approximately 100 colonies per plate. This density allows sufficient space between the colonies to allow for easy colony picking.

We recommend that you avoid creating large bubbles during plating, but there is no need to manually pop or disperse the small bubbles after plating. They will disperse over the incubation period of 10-14 days.

Re-cloning is a good practice to observe and is recommended if the number of colonies in the original dishes was very high.

There will likely be some residual methylcellulose contamination when colonies are picked and transferred to the 96-well plate with the liquid growth medium. The concentration of methylcellulose, however, should be low enough that it should not interfere with most assays.

Very important. In situations where the humidity is not high enough, we recommend that the 100 mm Petri dishes should be placed with an open dish containing sterile water inside a larger plastic container with a lid. Without very high humidity, the media will dry out over the culture period and this will impede the growth of the colonies.

We recommend 100 mm Petri dishes as these have been used to develop and test ClonaCell™ semi-solid media. We have found that the surface area of these dishes allows for easy colony picking. Other sizes of dish (e.g. 6-well plates) can be used. It is important to use non-coated dishes to prevent cells from sticking to the bottom of the plate and obscuring the colonies. The volume of media plated should be adjusted to reflect the surface area of the dish being used.