I'm performing migration assays and tube formation assays with MSC. I'm preconditioning MSC and to see the effect, I want to perform a tube formation assay, doing a coculture of MSC with HUVECS. There is not much data about the effect of the MSC on the HUVECS tube formation capacity.

How can I perform a co-culture of MSC (preconditioned) with HUVECS, to see the ability of modified MSC to enhance tube formation capacity of HUVECS?