The detection and biological activity of human antibodies to IL-2 in normal donors.
Antibodies to interleukin-2 (IL-2) have been reported in the sera of patients under therapies involving this cytokine and in the sera of patients infected with human immunodeficiency virus (HIV). Our study proves that auto-antibodies to IL-2 are present also, at a lower titre, in healthy individuals. These antibodies were affinity purified and studied for their capability to interfere with the in vitro biological activity of IL-2. Data obtained show that human anti-IL-2 antibodies can interfere with lymphocyte proliferation both in the lymphokine activated killer (LAK) cell assay and in the mixed lymphocyte reaction (MLR). However, the kinetics of inhibition by anti-IL-2 antibodies differs from LAK cell assay to MLR as the former are always inhibited in a time-independent manner, and the latter only by adding antibodies at the outset of culture. The neutralizing activity observed in vitro suggests that such antibodies play a part in the elaborate cytokine network by which the immune system regulates the amplitude and duration of its response.
Tiberio
L
L
Department of Biomedical Sciences and Biotechnology, University of Brescia, Italy.
Caruso
A
A
Pozzi
A
A
Rivoltini
L
L
Morelli
D
D
Monti
E
E
Balsari
A
A
D001323:Autoantibodies / Q000302:isolation & purification*; D015153:Blotting, Western; D002846:Chromatography, Affinity; D004797:Enzyme-Linked Immunosorbent Assay; D015658:HIV Infections / Q000276:immunology / Q000628:therapy; D006801:Humans; D007074:Immunoglobulin G / Q000302:isolation & purification; D007376:Interleukin-2 / Q000276:immunology* / Q000627:therapeutic use; D015979:Killer Cells, Lymphokine-Activated / Q000276:immunology; D008213:Lymphocyte Activation; D007959:Lymphocyte Culture Test, Mixed; D009369:Neoplasms / Q000276:immunology / Q000628:therapy; D011994:Recombinant Proteins / Q000627:therapeutic use
D001323:Autoantibodies; D007074:Immunoglobulin G; D007376:Interleukin-2; D011994:Recombinant Proteins