CFP10 (10 kDa culture filtrate protein) is a low molecular weight protein isolated from Mycobacterium tuberculosis culture filtrates. CFP10 and the 6 kDa early secretory antigen of T cells (ESAT6) are secreted in abundance by Mycobacterium tuberculosis and are frequently recognized by T cells from infected people. The genes encoding these proteins have been deleted from the genome of the vaccine strain Bacille Calmette Guerin (BCG).
CFP10 is one of a small number of secreted M. tuberculosis proteins now identified, that appear to play key roles in tuberculosis pathogenesis and in the stimulation of immunity.