Fig. 2.

(a–f) Representative images captured by confocal microscopy characterizing the primary cilia of controls (a and b), HT (c and d) and GD (e and f) thyroid follicles stained with acetylated α-tubulin (in green) and Arl13b (in red). In controls, primary cilia usually appear as one cilium per thyrocyte; however in HT and GD thyroid tissues, primary cilia exhibited a shorter length and some cells even lacked this structure (g). Quantification of primary cilia in a total of 5796 nuclei of 41 confocal images in control tissue, 7902 nucluei in 70 images captured in HT tissue and 6492 nuclei in 54 images of GD thyroid samples. Control samples had higher ciliated cells compared to HT and GD (****p < 0. 0001; by one-way ANOVA test). (h) Length quantification of a total of 3900 cilia (1300 cilia per group), as observed in the column graph, HT and GD presented shorter cilia compared to controls (****p < 0.0001, by Kruskal–Wallis test). (i) Histogram representing the frequency distribution of cilia length in the three groups. In HT and GD the distribution of cilia length overlaps around 0–3 μm, with the GD group having the shorter cilia length values. Control samples portrayed higher length values, around 4–5 μm.