Serum interleukin-15 is elevated in systemic lupus erythematosus

Rheumatology (Oxford). 2001 Aug;40(8):876-81. doi: 10.1093/rheumatology/40.8.876.


Objective: To investigate if interleukin-15 (IL-15) (rather than IL-2) is increased in systemic lupus erythematosus (SLE) and might be responsible for immunological abnormalities of SLE such as the increased lymphocytic expression of Bcl-2 and CD25.

Methods: Serum IL-15, IL-2 and tumour necrosis factor (TNF) levels of 65 SLE patients, 20 healthy persons and 10 rheumatoid arthritis (RA) patients were measured by enzyme-linked immunosorbent assay (ELISA). For 25 SLE patients, the percentage of CD25 + lymphocytes and the lymphocytic Bcl-2 levels were simultaneously determined by fluorocytometry. Peripheral blood mononuclear cells (PBMC) of 15 SLE patients were incubated with or without recombinant IL-15 and the influence on Bcl-2 and CD25 was determined.

Results: IL-15 was found to be elevated in 25 SLE sera (38%), but in none of the 20 healthy sera (P = 0.0005) and none of the 10 RA sera. Both lymphocyte CD25 and Bcl-2 expression significantly correlated with serum IL-15 and were increased by recombinant IL-15.

Conclusion: Serum IL-15 may in part be responsible for the immunological abnormalities seen in active SLE.

MeSH terms

  • Adult
  • Arthritis, Rheumatoid / immunology
  • Female
  • Humans
  • Interleukin-15 / blood*
  • Lupus Erythematosus, Systemic / immunology*
  • Lymphocyte Activation
  • Male
  • Middle Aged
  • Proto-Oncogene Proteins c-bcl-2 / analysis
  • Receptors, Interleukin-2 / analysis
  • Tumor Necrosis Factor-alpha / analysis


  • Interleukin-15
  • Proto-Oncogene Proteins c-bcl-2
  • Receptors, Interleukin-2
  • Tumor Necrosis Factor-alpha