A user-friendly, highly sensitive assay to detect the IFN-gamma secretion by T cells

Clin Biochem. 2008 Apr;41(6):440-4. doi: 10.1016/j.clinbiochem.2007.12.015. Epub 2008 Jan 3.


Objectives: Development of a user-friendly test alternative to ELISA-based assays to detect IFN-gamma by in vitro cultured peripheral blood mononuclear cells (PBMC) stimulated with pathogen-derived antigens.

Design and methods: The molecular components of an operational IFN-gamma ELISA-based test were applied in a lateral flow (LF) immuno-sandwich assay using up-converting phosphor (UCP) reporter particles. The analytical sensitivity of the UCP-LF IFN-gamma assay (ULIGA) was determined and the assay was qualitatively validated with a selection of 60 supernatants derived from PBMC cultures stimulated with M. leprae derived antigens, mitogen or medium alone.

Results: ULIGA indicated an analytical sensitivity better than 2 pg/mL, and demonstrated four orders of magnitude dynamic range. The assay correlated well with the IFN-gamma ELISA.

Conclusions: ULIGA allows detection well below the cutoff value (100 pg/mL) used to define positive responses in the IFN-gamma ELISA. The test procedure is less demanding in respect to equipment and labor, and is suited for testing single samples.

Publication types

  • Evaluation Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biological Assay / methods*
  • Cells, Cultured
  • Enzyme-Linked Immunosorbent Assay / methods
  • Humans
  • Interferon-gamma / metabolism*
  • Reproducibility of Results
  • Sensitivity and Specificity
  • T-Lymphocytes / cytology
  • T-Lymphocytes / metabolism*


  • Interferon-gamma