CFP-10 within bacterial proteins (also known as ESAT-6-like protein esxB or secreted antigenic protein MTSA-10 or 10 kDa culture filtrate antigen CFP-10) is a protein that is encoded by the esxB gene. CFP-10 is a 10 kDa secreted antigen from Mycobacterium tuberculosis. It forms a 1:1 heterodimeric complex with ESAT-6. Both genes are expressed from the RD1 region of the bacterial genome and play a key role in the virulence of the infection.