Differential activity of interleukin 1 alpha and interleukin 1 beta in the stimulation of the immune response in vivo.
The biological activities of human recombinant interleukin (IL) 1 alpha and IL 1 beta were compared in different biological systems. The two IL 1 forms were equally active in vitro in inducing proliferation of murine thymocytes and of the murine T helper clone D10.G4.1, and in triggering release of prostaglandin E2 from human skin fibroblasts. In vivo, IL 1 alpha and IL 1 beta were similarly pyrogenic both in rabbits and mice, and could equally increase the circulating levels of the acute phase protein serum amyloid A in mice. However, only IL 1 beta showed immunostimulatory activity in vivo, as it could enhance the number of specific antibody-producing cells in the spleen of mice immunized with either a T-dependent or a T-independent antigen. Although devoid of immunostimulatory activity, IL 1 alpha could efficiently compete immunostimulation induced by IL 1 beta, suggesting an effective interaction with the IL 1 receptor. Thus, IL 1 beta appears to have an important role in the positive regulation of immune responses, while IL 1 alpha may act as down-regulator of the IL 1 beta effect.
Boraschi
D
D
Laboratory of Immunopharmacology, Sclavo Research Center, Siena, Italy.
Villa
L
L
Volpini
G
G
Bossù
P
P
Censini
S
S
Ghiara
P
P
Scapigliat
G
G
Nencioni
L
L
Bartalini
M
M
Matteucci
G
G
D000818:Animals; D000917:Antibody Formation / Q000187:drug effects*; D015232:Dinoprostone / Q000096:biosynthesis; D006801:Humans; D066298:In Vitro Techniques; D007249:Inflammation / Q000503:physiopathology; D007375:Interleukin-1 / Q000494:pharmacology*; D008213:Lymphocyte Activation / Q000187:drug effects*; D051379:Mice; D008809:Mice, Inbred C3H; D011749:Pyrogens; D011817:Rabbits; D011994:Recombinant Proteins
D007375:Interleukin-1; D011749:Pyrogens; D011994:Recombinant Proteins; D015232:Dinoprostone