Interleukin-1beta stimulates interleukin-8 production and gene expression in synovial cells from human temporomandibular joint.

PURPOSE: The aims of the present study were to isolate and characterize cultured synovial cells from human temporomandibular joint (TMJ) specimens and to investigate the effect of interleukin (IL)-1beta on IL-8 production and gene expression in those cells.

MATERIALS AND

METHODS

Synovial cells (HTS cells) were isolated from TMJ synovial tissues using an outgrowth method and then primary cultured. The cells were examined for cell-specific markers of fibroblast, macrophage, and dendritic cells using immunocytochemistry. HTS cells were then treated with IL-1beta, and amounts of IL-8 were measured by enzyme-linked immunosorbent assay. IL-8 production and expression were also investigated using immunocytochemistry and a reverse transcription-polymerase chain reaction method.

RESULTS

HTS cells were positive for the fibroblast-specific markers, such as vimentin and propyl 4-hydroxylase. The macrophage or dendritic cell markers and HLA class II antigen were negative. Furthermore, IL-1beta enhanced IL-8 production in HTS cells in a time- and dose-dependent manner and stimulated IL-8 gene expression.

CONCLUSIONS

HTS cells may provide important advantages for studies of the cellular and molecular mechanisms in the TMJ. In addition, we found that IL-1beta stimulated IL-8 production through an increase in IL-8 gene expression in HTS cells, which may be associated with the increase of infiltrating inflammatory cells seen in the synovial membrane of TMJ disorders.