This poster presents a study on the morphology of the primary cilium in neurons derived from induced pluripotent stem cells (iPSCs) of patients with spinocerebellar ataxia type 17 (SCA17).
The researchers aimed to generate brain organoids from patient-derived iPSCs to study primary cilium structures. They used dermal fibroblasts from a healthy donor, a carrier, and an SCA17 patient to induce pluripotent stem cells, which were then differentiated into neuroepithelium, neuronal progenitor cells, and midbrain organoids using specific small molecules and growth factors. The samples were analyzed via 2D culture generation, confocal microscopy, quantitative RT-PCR, and transmission electron microscopy.
The results show that the nuclear area in patient cells was 1.5 times smaller than in healthy controls. Additionally, the expression of primary cilia genes DYNC2H1 and TRAF3IP1 in patient cells was significantly decreased by 2.5 and 7.9 times, respectively. Transmission electron microscopy demonstrated that the ultrastructure of the primary cilia in patient organoid cells remained normal. However, immunocytochemical analysis of 2D cultures revealed that the cilia length in patient cells was 1.5 times shorter compared to healthy control cells.
In conclusion, brain organoids from both healthy donors and SCA17 patients express predominantly neuronal markers. Although the primary cilia in neurons from SCA17 patients display normal ultrastructure, their length is significantly reduced, and the expression levels of the primary cilia-related genes DYNC2H1 and TRAF3IP1 are substantially downregulated.