Four simple cloning methods

Cells should be dispersed as described in 7.1.1, but the culture vessel should contain many small fragments (0.05 cm2) of coverslips to which the cells will attach and grow. Using sterile forceps remove coverslips fragments on which single cells have attached (check this microscopically) and transfer them to separate wells in a tissue culture tray ( 3.2). 

An alternative method involves using a microcapillary to select 

Under certain conditions cells will form colonies when not attached 

Macpherson (1973b) points out factors which promote the growth of 

Confluent cultures containing (2 X 106 cells/90 mm dish are irradiated with 4000-6000 rads of y-radiation from a cobalt source. Irradiation should last for less than 1 min and a variety of cell lines (e.g. HeLa, BHK21/C13 or 3T3) are suitable (Puck et al., 1956). These cells may be used directly or may be trypsinised into smaller vessels. They may appear healthy for up to 4 weeks but do not divide. 

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