Effect of Inflammatory Mediators on the Differentiation Potential of Dental Pulp Stem Cells in vitro

Abstract

Abstract Background Dental pulp stem cells (DPSCs) are of special relevance in future regenerative dental and immunological medical therapies due to their differentiation and immunologic potentials. This in vitro study examined the effect of the inflammatory cytokines tumour necrosis factor-α (TNF-α), interleukin (IL)-1β, and IL-6 on osteogenic, chondrogenic, and adipogenic differentiation of DPSCs. Methods DPSCs were isolated from the impacted third molar dental pulp and determined with flow cytometry analysis. DPSCs were divided into 15 groups: three unstimulated control groups and four groups stimulated with TNF-α, IL-1β, IL-6, and a combination of all three to undergo osteogenic, chondrogenic, and adipogenic differentiation protocols. Next, the differentiation of each group was examined with different staining procedures under a light microscope. Histological analysis of osteogenic, chondrogenic, and adipogenic differentiated pellets was assessed using a modified Bern score. Statistical significance determined using one-way analysis of variance, and correlations were assessed using Pearson’s test (two-tailed). Results Unstimulated DPSCs displayed a higher differentiation ability than the other groups stimulated with inflammatory cytokines. Conclusions DPSCs have high osteogenic, chondrogenic, and adipogenic differentiation capabilities. Pretreatment with inflammatory cytokines decreases the differentiation ability in vitro, thus inhibiting tissue formation.