TNF revisited: TNF-independent antitumor activity in sera of mice sensitized with Propionibacterium acnes and challenged with lipopolysaccharide.
Sera of mice sensitized with bacteria and subsequently challenged with lipopolysaccharide promote hemorrhagic necrosis of tumors in vivo and display cytotoxic activity against tumor cells in vitro, which has been attributed to the induction of tumor necrosis factor (TNF). Here, we describe the induction of a previously unrecognized antitumor activity in such sera, which is distinct from TNF but displays tumor-specific cytocidal activity in vitro as well as potent tumor-regressing activity in vivo. Biochemical analysis of this activity yielded a molecular mass of approximately 150 kDa, closely resembling a novel tumoricidal factor of murine macrophages (Mphi) termed MTC 170 (Mphi tumor cytotoxin, approximate molecular mass 170 kDa), which we have previously proposed to constitute a major effector pathway for the destruction of tumor cells by activated Mphi.
Schwamberger
Günter
G
Max-Planck-Institut für Immunbiologie, Frieburg, Germany. gschwamberger@yahoo.de
Hammerl
Peter
P
Ferber
Ernst
E
Freudenberg
Marina
M
Galanos
Chris
C
D000818:Animals; D017209:Apoptosis / Q000502:physiology; D001854:Bone Marrow Cells / Q000166:cytology; D003602:Cytotoxicity, Immunologic / Q000276:immunology*; D005260:Female; D016908:Gram-Positive Bacterial Infections / Q000097:blood*; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008264:Macrophages / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D009374:Neoplasms, Experimental / Q000276:immunology / Q000628:therapy*; D011425:Propionibacterium acnes / Q000276:immunology*; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000627:therapeutic use*
D008070:Lipopolysaccharides; D014409:Tumor Necrosis Factor-alpha