Interleukin-1β activity and collagen synthesis in human dental pulp fibroblasts

Immunopathologic reactions play a significant role in inflammatory diseases of dental pulp. Interleukin-1beta (IL-1beta) is recognized as a key player in mediating cellular immune response. In this study, we measured the content of IL-1beta and its effect on collagen synthesis in cultures of fibroblasts derived from healthy and diseased dental pulps. We found that diseased pulp fibroblasts contain 2.5-fold greater amounts of IL-1beta and synthesized 80% greater amounts of collagen compared with healthy pulp fibroblasts. However, exogenous IL-1beta failed to stimulate collagen synthesis by diseased fibroblasts, whereas collagen synthesis by healthy pulp fibroblasts was stimulated by more than 2-fold. These observations imply that pulp disease induces abnormalities associated with fibroblast response toward IL-1beta.