Protocol for selective in vivo labeling of bone marrow plasma cells by intrafemoral antibody injection in mice.

Plasma cells are essential for long-term humoral immunity and are enriched in the bone marrow. Here, we present a protocol for selective labeling of plasma cells within a single mouse femur, using an intrafemoral antibody injection approach. We describe steps for the direct injection of fluorochrome-conjugated antibodies into the medullary cavity. We then detail procedures for bone marrow cell collection and analysis by flow cytometry. This protocol enables investigation of bone marrow plasma cell retention, redistribution, and mobilization. For complete details on the use and execution of this protocol, please refer to Zhu et al.1.