I only know about human T cells and also there, as you said, it depends on the assay, but I guess it could be easily 5 days if the cells are naive, but if you're aiming at memory cells it is way faster which might even be within a couple of hours. The activation can occur pretty fast, memory cytotoxic T cells can start releasing Granzyme B upon activation super fast. For other populations in can even take 3 days in my experience...

So I figure there is no easy answer to that and maybe you need to find the right duration by trying it and checking for proliferation markers like Ki67 via flow cytometry.

I hope that helped at least a tiny little bit :D

Thanks a lot for your answer!

I want to do BrdU assays to asses the proliferation, I might also go for Ki67, now ... I hoped to narrow down my time frame a bit with this question :) ...

Thanks Polina, for sharing your experience!