'DNA vaccine expresses protein antigen' vs 'expresses'

[zhengj2007]

'DNA vaccine expresses protein antigen' is a VO specific relation, a subProperty of RO: 'expresses'.

The relation 'DNA vaccine expresses protein antigen' just used in once to DNA and MVA encoding ME-TRAP. However, RO: 'expresses' is widely used in VO, relate vaccine to protein.

I am wondering whether we need this specific relation unless we need to use it to validate the axioms (if so, need to to specify the domain and range in VO).

VO has DNA vaccine, antigen, protein (we may add 'antigen role' if it is an antigen). So, using 'expresses' can infer whether it is 'DNA vaccine expresses protein antigen' based on the subject and object.