Use always human serum decomplemented for macrophages/monocytes/DCs... you will avoid the risk of the cells getting matured/activated.

I used to use 10% human serum in MDM to culture

I do agree with the previous answers. If you want unperturbed human monocytes, use human serum (autologous would be the best) at 10-20%. If you want the monocytes acyivated, use FBS (and possibly add growth factors of choice). Good luck!

Both will support  human monocyte differentiation into macrophages.  However there is every possibility that human sera will contain several macrophage modulating ingredients  such as circulating cytokines that could  influence the in vitro differentiating  macrophages. 

It is always better to use human serum. It will help avoiding the risk of activation of the cells.

Hello

you can use 10% human serum .

Good Luck

http://link.springer.com/protocol/10.1385%2F1-59259-838-2%3A105

10% human serum better fo macrophage culture

No doubt, as supported by all colleagues, human serum is the best choice, particularly because human cells are not used to work with bovine proteins.

Once differentiated into MØ, you can work with very low levels of human serum for your test if it's overnight. For example, for cytokine induction, we work with 0.2% that limits artifactual background activation.