I need to perform a transwell assay on murine BMDMs (bone marrow derived macrophages). I am not sure how long I need to leave the macrophages in incubator to allow the migration. I am finding in literature all kind of time points, from 90 minutes to 36 hours.

My treanswell will have a monolayer of mouse endothelial cells, on the upper chamber I am planning to add 100ul of 5X105 BMDMs, in the lower well I will add 600ul of media + chemoattractant. I am planning to stain the lower layer of the membrane of the transwell.

Any suggestion on the time point? Any suggestion on the number of macrophages?