[biophetik]

Magnetic bead filteration is commonly used to filter immune cells, but they are expensive. I used to work for a lab that did this on a daily basis. Common problems with it were getting enough cells to run the assays, and the process of extraction is damaging to the cells. So you need a lot of starting material and then after that they don't stay alive for very long. You can treat and freeze after isolation but thawing only decreases the amount of healthy cells.