Antitumor activity of mycobacterial glycolipid A1.

Glycolipid A1 isolated from Mycobacterium bovis BCG, when dissolved in olive oil and injected together with Line 10 transplantable hepatoma cells, is able to elicit a host response which results in the abrogation or retardation of tumor growth in syngeneic guinea pigs. Glycolipid A1 does not have adjuvant activity for delayed type hypersensitivity, and antibodies to A1 have not been detected in the sera of guinea pigs during or after the tumor abrogation induced by A1 injection Glycolipid A1 does not share antigenic determinants with Line 10 cell lipid fractions. The possible role of the granuloma response elicited by A1 in controlling tumor growth is discussed.