Immunoprecipitation and Mass Spectrometry Reveals Interactors of CD11b

We aimed to identify CD11b-associated inhibitory receptors,that control phagocytosis when engaged by ligands expressed on cancer cells. CD11b was immunoprecipitated from mouse bone marrow-derived macrophages (BMDMs), and the associated proteins were analyzed using mass spectrometry. A few inhibitory receptors were identified in CD11b immunoprecipitates from wild-type BMDMs, but not from CD18 (the β2 subunit of Mac-1)-deficient BMDMs, which lack CD11b.