The so-called interleukin-2 inhibitory activity of human serum is largely cytotoxic to mouse cells.
No specific interleukin-2 (IL-2) inhibitor has ever been demonstrated in human, mouse, or any other animal serum. Native mouse serum contains activities which completely inhibit IL-2-dependent and IL-2-independent in vitro proliferation of cells of different animal species by a non-cytotoxic mechanism. The decisive inhibitory component of mouse serum has a molecular weight of about 80,000, is heat-labile and has not been found in other animal sera. Also, native human serum completely suppresses the proliferation of various mouse cell types, predominantly by a cytotoxic effect caused by natural IgM antibodies and complement. Heat-inactivated human serum is no longer cytotoxic to mouse cells, and inhibits the proliferation of mouse cells much less than native serum. There is thus no evidence for a specific IL-2 inhibitor in mouse, human or other serum.
Friemel
H
H
Institut für Immunologie, Wilhelm-Pieck-Universität, Rostock, G.D.R.
Wolf
V
V
Werner
H
H
Plantikow
A
A
Ulmer
A J
AJ
Musehold
J
J
D000818:Animals; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D003165:Complement System Proteins / Q000276:immunology; D006131:Growth Inhibitors / Q000097:blood* / Q000302:isolation & purification / Q000494:pharmacology; D006801:Humans; D007075:Immunoglobulin M / Q000276:immunology; D007376:Interleukin-2 / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D008322:Mammals / Q000097:blood; D051379:Mice; D008808:Mice, Inbred CBA / Q000097:blood*; D008970:Molecular Weight
D006131:Growth Inhibitors; D007075:Immunoglobulin M; D007376:Interleukin-2; D003165:Complement System Proteins