Hello, it depends on what type of tissue you are detecting macrophage in, and tailor the antibody use accordingly. For example CD68, stains up macrophages but may also stain up other cells such as endothelial. CD11b and c are expressed by different types of dendritic cells under different context. so i suggest finding an antigen that works best for your scenario. hope it helps

There are no absolute markers. You have ot decide what mechanism you are interested in. Genome markers are gaining importance

I think the following articles might be helpful:

DOI: 10.1172/JCI39717

and

DOI: 10.1165/rcmb.2012-0366MA

In short: differential expression of F4/80 and CD11c helps distinguishing alveolar from interstitial macrophages and DCs