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When you write cloning and expansion I assume you are cloning and expanding for making a stable transfectant. If that is so, of course you will need to add whatever your selection drug is to the what is to follow. I believe what you are getting at is the difficulty of cloning a cell since there are few cells in a well or in a dish. Cells like to be around other cells so I recommend using conditioned medium that you can make. Conditioned medium contains nutrition yet since it has had cells growing in it it also has other factors that will make your cells happy while you are cloning them. To make conditioned medium use the same cells that you are cloning (untransfected) plate them at about 20% confluency and let them grow overnight. The next morning, using sterile technique, remove the medium and centrifuge to remove debris. Then add 50% fresh medium and 50% conditioned medium when you clone your cells. You can use this until your cells begin to grow, Once the cells reach 30% confluency or so you can add media that is not conditioned. If you are doing a drug selection for stables be sure to do a killing curve so you know the dose and the length of time it will take to do the selection. I hope this helps.