A competitive enzyme-linked immunoassay (ELISA) for the measurement of soluble human interleukin-2 receptors (IL-2R, Tac protein).


Journal Article

A solid-phase, competition enzyme-linked immunosorbent assay (ELISA) was established for the quantitative measurement of soluble (human) interleukin-2 receptors (IL-2R). The ladder of reagents from the solid phase up consisted of: (1) recombinant DNA-derived, purified IL-2R, (2) sample-containing soluble IL-2R and fluorescein isothiocyanate (FITC)-conjugated monoclonal antibody, 7G7/B6, directed against the IL-2R, (3) alkaline phosphatase-conjugated rabbit anti-FITC, and (4) substrate. This ELISA was compared with a 'sandwich' ELISA for soluble IL-2R. The competitive ELISA was less sensitive than the 'sandwich' assay, being capable of measuring 5000 versus 31 U/ml, respectively. While both anti-Tac and 7G7/B6 in the IL-2R-containing sample inhibited the 'sandwich' assay, only 7G7/B6 inhibited the competition assay. Anti-mouse immunoglobulin enhanced the 'sandwich' assay and inhibited the competitive assay; both effects could be overcome by the addition of normal mouse immunoglobulin in the sample buffer. Studies of a patient's serum receiving anti-Tac as therapy for the adult T cell leukemia demonstrated that rises in the level of IL-2R occurring with anti-Tac therapy, as measured with the competition assay, were masked in the 'sandwich' assay. This competition ELISA will be useful for measuring soluble IL-2R levels in patients receiving anti-Tac as therapy for various immunologic disorders.

Full Text

Duke Authors

Cited Authors

  • Goldstein, AM; Marcon, L; Cullen, BR; Nelson, DL

Published Date

  • February 24, 1988

Published In

Volume / Issue

  • 107 / 1

Start / End Page

  • 103 - 109

PubMed ID

  • 3125256

Pubmed Central ID

  • 3125256

International Standard Serial Number (ISSN)

  • 0022-1759

Digital Object Identifier (DOI)

  • 10.1016/0022-1759(88)90015-4


  • eng

Conference Location

  • Netherlands