Tissue engineering and regenerative medicine approaches harness knowledge of cell populations and the factors that direct cellular function to inform tissue formation.
In some cases, other species present an innate capacity to regenerate organs or tissues that humans are not capable of replacing spontaneously, and these species can serve as models for the study of cells and pathways involved in regeneration. A recent article by Bloomquist et al.reports investigation of tooth and taste bud progenitor cell populations in a Lake Malawi chichlid fish model, which replaces it teeth and renews taste buds throughout life. The authors found through in situ hybridization, fluorescent labeling, and RNA-Seq studies an anatomic linkage between tooth replacement and taste bud renewal in the fish model, co-localization of the structures in the oropharynx, and differential expression patterns between the structures. Interestingly, the team demonstrated that temporary loss of BMP signaling in replacement teeth drove assumption of taste bud-like characteristics in the dental cells. Similar cellular plasticity results were reported in a mouse model, in which the tooth and taste bud structures are not co-localized. Overall, the study suggests retention of an inherent plasticity in oral epithelial cells that may be mediated by specific factors and progenitor cell populations to drive regeneration of dental tissues. Fundamental findings of this nature may inform continued development of approaches for craniofacial tissue regeneration.
Developmental plasticity of epithelial stem cells in tooth and taste bud renewal.
Bloomquist RF, Fowler TE, An Z, Yu TY, Abdilleh K, Fraser GJ, Sharpe PT, Streelman JT. Proc Natl Acad Sci U S A. 2019:201821202.