simplify 'cell line cell' axioms

[zhengj2007]

cell line cell:

• cultured cell
• secondary cultured cell
• derives from' some 'primary cultured cell'
• (is_specified_output_of some 'establishing cell line') or ('derives from' some (is_specified_output_of some 'establishing cell line'))

The 'secondary cultured cell' is a subClassOf 'cultured cell'. So, we can remove 'cultured cell'.

'establishing cell line' is a process whereby a new type of cell line is created, either through passaging of a primary cell culture to relative genetic stability and compositional homogeneity, or through some experimental modification of an existing cell line to produce a new line with novel characteristics (e.g. immortalization or some other stable genetic modification, or selection of some defined subset).

So propose the axioms as:
cell line cell = 'secondary cultured cell' and is_specified_output_of some 'establishing cell line'