What are you trying to do with them?  Are you differentiating them?

I have cultured it before, what protocol do U use, we need to know to be able of say something.

This is how we isolate them:  

1.       Resuspend counted buffy coat cells at a concentration of 107 cells/75cm2 flask in RPMI 1640 + 1% Human Serum.

2.       Incubate cells for 1 hour at 37°C, 5% CO2.

3.       Remove non-adherent cells and wash adherent cells 2-3X with warm PBS.

Add 10mL complete RPMI 1640 (with 10% FBS)/flask.

You should be able to keep them in RPMI media from there.  If you are differentiating them into macrophages (M1 & M2 populations) then we 

1.       Wash 2-3X with warm PBS.

2.       Add 15mL RPMI + pen/strep + 10% Human Serum to flask and incubate for 12 days.  Change culture media every 3 days.