AG 85, a major secretion protein of Mycobacterium tuberculosis, can be identified in ancient bone.

For the confirmation of Ag 85 in ancient and recent ECM of native macerated human bone, five cases were investigated. In three individuals, highly positive results for Ag 85 were identified in Western blot: 1) a male from Arzhan, South Siberia, dating from the 7th century BC, 2) a male from Kirchberg in Hesse, Germany, dating from the 10th - 12th century AD and 3) a recent female with a proven diagnosis of TB. As a negative control, a recent male is presented who did not suffer from TB. In another recent male, Ag 85 could be identified only very weakly. From cases in the literature it is well-known that highly positive results for Ag 85 indicate active TB, however, weakly positive results indicate a silent initial infection with Mtb. Thus, apparently, also in ancient individuals, it might well be possible to differentiate between diseased persons and disease carriers using paleoproteomic techniques.