To study the immune mechanism of 99Tc-MDP in the treatment of patients with rheumatoid arthritis (RA).
In vitro, 99Tc-MDP was added to the cultures of peripheral blood mononuclear cells (PBMC) derived from healthy subjects and RA patients. The levels of IL-1 and sIL-2R from PBMC affected by 99Tc-MDP were determined with enzyme linked immunosorbert assays (ELISA).
The IL-1 production by PBMC of RA, either in the medium alone (spontaneously) or in the presence of lipopolysacchride (LPS) stimulation, was suppressed by 99Tc-MDP; and the sIL-2R by PBMC of RA, either in the medium alone (spontaneously) or in the presence of phytohemagglutinin (PHA) induction, was inhibited by 99Tc-MDP.
99Tc-MDP acts on PBMC and a possible immune activity by 99Tc-MDP is related to the suppression of IL-1 and sIL-2R in RA patients.