Detection of interleukin-1 beta in human periapical lesions.

Interleukins are involved in modulating bone cell activity. Interleukin-1 (IL-1) has been shown to be potent stimuli of bone resorption in organ culture. This hormone-peptide is produced primarily by monocytes and macrophages. Diverse inflammatory cell types are clearly present in periapical lesions. The purpose of this study was to detect IL-1 beta activity in human periapical lesions. Eight human periapical lesions were examined for the presence of IL-1 beta. Pulp tissue of clinically impacted teeth were used as controls. Each specimen was quick-frozen and stored in liquid nitrogen. IL-1 beta activity was measured with, an IL-1 beta enzyme-linked immunosorbent assay that used monoclonal antibodies specific for IL-1 beta. Periapical samples exhibited significant activity of IL-1 beta (mean 604.4 +/- 563.0 pg/mg protein), whereas normal pulp had no activity. These results demonstrate that IL-1 beta is produced and released locally in inflammatory periapical lesions to mediate bone resorption.