Updated project metadata. To identify the macrophage binding partner of Mtb BfrB, we selected and purified BfrB tagged with GST, and incubated it with THP-1 lysates before performing GST Pullodwn. Then the eluted protein were examined by sliver stain. Using mass spectrometry, we identified a protein with an apparent molecular mass of 28 KDa as RPS3, an essential subunit of NF-κB involved in the regulation of key genes in rapid cellular activation response.