APP and Granuloma: The presence of serum amyloid A (SAA), a highly inducible acute-phase reactant and amyloid precursor protein, was readily detected in CD68+ macrophages and multi-nucleated giant cells from sarcoidosis patient granulomas in various organs (lung, lymph nodes, skin, liver) and in mycobacterial KatG–bead–induced granulomas in mice [79].