Serum And Synovial Interleukin-15 Level In Different Rheumatic Diseases

Abstract EN

This study was undertaken in a trial to assess the possible role of interleukin 15 (IL-15) in different rheumatic diseases.

Its level was measured in the sera of fifty patients; twenty rheumatoid arthritis (RA), ten osteoarthritis (OA), ten systemic lupus erythematosus (SLE) and ten systemic sclerosis (SSC) as well as ten healthy controls using the ELISA technique.

The same estimation was performed on the synovial fluid (SF) of ten RA, seven OA and five normal controls that had post-traumatic effusions.

The study revealed no statistical significant difference regarding serum IL-15 between the patients and normals (p>0.05).

Comparison between the four studied patient groups showed no significant difference in the serum IL-15 between each other (p>0.05).

But there was a significant increase in the synovial IL-15 in RA than in normal SF (p<0.01).

There was a significant higher level of IL-15 in SF more than in the serum of RA patients (241.9±230.8 pg/ml versus 93.5±157.5 pg/ml respectively, p<0.01).

In addition, the SF levels of IL-15 in RA patients significantly exceeded those present in OA (241.9±230.8 versus 64.1±60.9 pg/ml respectively, p<0.001).

No correlation was found between IL-15 level whether serum or synovial and any parameter of disease activity among the studied four patients’ groups.

Also, there was no correlation between the IL-15 levels whether synovial or serum with the corresponding levels of C3 complement.

It can be concluded that a higher concentration of IL-15 is found mainly in RA synovial fluid.

This locally produced cytokine can contribute to the pathogenesis of RA.

However, it cannot be used as a parameter of disease activity.