Expression of the tumor necrosis factor locus is not necessary for the cytolytic activity of T lymphocytes.
In order to test whether tumor necrosis factors alpha (TNF-alpha) or beta (TNF-beta, also known as lymphotoxin) are involved in the lysis of target cells by cytolytic T lymphocytes, we probed for the presence of the TNF mRNAs in several quiescent and activated CTL clones. No TNF mRNA could be found in constitutively cytolytic Lyt-2+ clones, and only two out of three clones tested accumulated TNF mRNA after stimulation with phorbol myristate acetate and ionomycin. Of two L3T4+ clones that can be induced to become cytolytic by a combination of antigen and IL-1, only one accumulated TNF-beta mRNA in the process. The PC60 rat X mouse T cell hybrid, which becomes cytolytic in response to a combination of IL-1 and IL-2, also failed to accumulate TNF mRNA after stimulation with these agents. Our results strongly suggest that TNF-alpha or -beta are not necessary agents of the cytolytic activity exhibited by antigen-specific T lymphocytes.
Jongeneel
C V
CV
Ludwig Institute for Cancer Research, Lausanne Branch, Epalinges, Switzerland.
Nedospasov
S A
SA
Plaetinck
G
G
Naquet
P
P
Cerottini
J C
JC
D000818:Animals; D002460:Cell Line; D003602:Cytotoxicity, Immunologic; D004987:Ethers / Q000494:pharmacology; D006825:Hybridomas / Q000187:drug effects / Q000378:metabolism; D007375:Interleukin-1 / Q000494:pharmacology; D015759:Ionomycin; D051379:Mice; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D013602:T-Lymphocytes, Cytotoxic / Q000187:drug effects / Q000276:immunology*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*
D004987:Ethers; D007375:Interleukin-1; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D015759:Ionomycin; D013755:Tetradecanoylphorbol Acetate