TY - JOUR

T1 - IgG autoantibodies against interleukin 1 alpha in sera of normal individuals

AU - Svenson, M

AU - Poulsen, L K

AU - Fomsgaard, A

AU - Bendtzen, K

PY - 1989/4

Y1 - 1989/4

N2 - A pool of human sera from healthy blood donors was found to interfere competitively with the binding of 125I-labelled human recombinant interleukin 1 alpha (rIL-1 alpha) to the murine T-cell line EL4. The interference was reversible at the cellular level, and direct binding of the ligand to serum factors was therefore investigated. After preincubation of [125I]rIL-1 alpha with pooled serum, the 125I activity eluted in two peaks from a Sephadex G-75 column. The first was located in the void volume. The second eluted together with monomer rIL-1 alpha. An almost complete displacement of the high molecular weight 125I fraction was achieved with an excess of unlabelled rIL-1 alpha but not with rIL-1 beta. The serum factors binding to [125I]rIL-1 alpha were located in the molecular weight range 100,000-200,000, judged by fractionation on a Sephacryl S-400 column, and the factors were bound to immobilized protein A. Furthermore, [125I]rIL-1 alpha preincubated with serum co-precipitated with a specific rabbit anti-human IgG antibody. Screening of 29 sera from normal individuals showed similar effects in three cases. We conclude that approximately 10% of normal human sera contains detectable IgG autoantibodies to IL-1 alpha.

AB - A pool of human sera from healthy blood donors was found to interfere competitively with the binding of 125I-labelled human recombinant interleukin 1 alpha (rIL-1 alpha) to the murine T-cell line EL4. The interference was reversible at the cellular level, and direct binding of the ligand to serum factors was therefore investigated. After preincubation of [125I]rIL-1 alpha with pooled serum, the 125I activity eluted in two peaks from a Sephadex G-75 column. The first was located in the void volume. The second eluted together with monomer rIL-1 alpha. An almost complete displacement of the high molecular weight 125I fraction was achieved with an excess of unlabelled rIL-1 alpha but not with rIL-1 beta. The serum factors binding to [125I]rIL-1 alpha were located in the molecular weight range 100,000-200,000, judged by fractionation on a Sephacryl S-400 column, and the factors were bound to immobilized protein A. Furthermore, [125I]rIL-1 alpha preincubated with serum co-precipitated with a specific rabbit anti-human IgG antibody. Screening of 29 sera from normal individuals showed similar effects in three cases. We conclude that approximately 10% of normal human sera contains detectable IgG autoantibodies to IL-1 alpha.

KW - Adult

KW - Animals

KW - Autoantibodies

KW - Binding Sites, Antibody

KW - Cell Line

KW - Chromatography, Gel

KW - Humans

KW - Immune Sera

KW - Immunoglobulin G

KW - Interleukin-1

KW - Mice

KW - Molecular Weight

KW - Journal Article

KW - Research Support, Non-U.S. Gov't

M3 - Journal article

C2 - 2785711

VL - 29

SP - 489

EP - 492

JO - Scandinavian Journal of Immunology, Supplement

JF - Scandinavian Journal of Immunology, Supplement

SN - 0301-6323

IS - 4

ER -