Endocrine Abstracts

The thyroid gland regulates growth and metabolism by producing thyroid hormones in follicles composed of thyrocytes. So far, thyroid cells were thought to be a homogeneous population. To uncover genetic heterogeneity in the thyrocyte population and to molecularly characterize the non-thyrocyte cells surrounding mature follicles or follicles in development, we have developed single-cell transcriptome atlas of mouse and human thyroid organoids derived from pluripotent stem cells and zebrafish thyroid gland. Our results identify and validate transcriptional differences within the nominally homogeneous mature thyrocyte population. Furthermore, these single-cell transcriptome analyzes identified cells that form the "niche" involved in thyrocyte development and maturation in vivo and in vitro, such as immune cells, fibroblasts, and cardiac cells. In addition, we identified TGF-beta as a negative regulator of thyroid maturation in vitro. Our study highlights the potential of molecular characterization of single cells for understanding and improving thyroid development and maturation in vivo and in vitro.

Bullets:

• Organoids

• Zebrafish

• Pluripotent stem cells

• Single cells RNAseq

• TGF beta pathway