Abstract
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.
| Original language | English |
|---|---|
| Journal | Scandinavian Journal of Immunology |
| Volume | 29 |
| Issue number | 4 |
| Pages (from-to) | 489-92 |
| Number of pages | 4 |
| ISSN | 0300-9475 |
| Publication status | Published - Apr 1989 |
Keywords
- Adult
- Animals
- Autoantibodies
- Binding Sites, Antibody
- Cell Line
- Chromatography, Gel
- Humans
- Immune Sera
- Immunoglobulin G
- Interleukin-1
- Mice
- Molecular Weight
- Journal Article
- Research Support, Non-U.S. Gov't
