I'm new to the field, in a new lab, and looking for macrophage lines that would be best to use for some in vitro work involving adding tumor cells grown/ modified in vitro to macrophages. There are so many possibilities. Or, is it good to use primary macrophages? How do you pinpoint what lines (or primary cells) are best for cancer work? In my particular cancer field, it seems like most work is in vivo, so just perusing those papers hasn't gotten me very far. Thanks for any tips.