False positive results in class-specific rheumatoid factor (RF) assays due to interaction between RF and Fc fragments of anti-immunoglobulin indicator reagents

Research output: Contribution to journalArticle


A recently developed, simple immunological method, diffusion-in-gel ELISA, has been adapted for class-specific determination of rheumatoid factor (RF). Evidence was obtained of an analytical error due to interaction between RF and antigenic determinants on the Fc part of the indicator immunoglobulin (Ig) molecules used. This was eliminated by replacing the usual indicator reagent, complete Ig molecules, by conjugated Fab or F(ab')2 fragments. The findings imply that unless the RF-Fc interaction mentioned is avoided in the assaying technique, false positive results may be obtained for, e.g. IgG RF and IgA RF in sera containing IgM RF.


External organisations
  • External Organization - Unknown
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Immunology in the medical area


  • rheumatoid factor, immunoassay, immunoglobulin class
Original languageEnglish
Pages (from-to)171-182
JournalJournal of Immunological Methods
Issue number1-2
Publication statusPublished - 1983
Publication categoryResearch
Externally publishedYes

Bibliographic note

The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Bioimplant Research (013242910)