Patient derived stem cells for discovery and validation of novel pathogenic variants in inherited retinal disease

Novel roles for voltage‐gated T‐type Ca 2+ and ClC‐2 channels in phagocytosis and angiogenic factor balance identified in human iPSC‐derived RPE

“…3 Conversely, the same technology can be used to introduce genetic variants of uncertain significance into wild-type iPSC lines in order to elucidate their pathogenicity. 4 To ensure the robustness of these widespread applications, iPSC-derived models must be thoroughly validated upstream by assaying the expression of specific markers and functions indicative of cell maturity. 1 One of the first tissues to have been differentiated from hiPSC was the retinal pigment epithelium (RPE), due to the inherent ability of this tissue to spontaneously differentiate.…”

“…In addition, the coupling of precise genome editing methods to hiPSC technology allows a refined analysis of disease‐causing mutations by creating isogenic controls from patient‐specific iPSC 3 . Conversely, the same technology can be used to introduce genetic variants of uncertain significance into wild‐type iPSC lines in order to elucidate their pathogenicity 4 . To ensure the robustness of these widespread applications, iPSC‐derived models must be thoroughly validated upstream by assaying the expression of specific markers and functions indicative of cell maturity 1 …”

Minigene Splicing Assays and Long-Read Sequencing to Unravel Pathogenic Deep-Intronic Variants in PAX6 in Congenital Aniridia

“…In this sense, immortalized cell lines may behave differentially with respect to patient tissues, so different outcomes may be obtained depending on the nature of the tissue from which the RNA is derived [ 33 ]. Alternatively, adult somatic cell reprogramming techniques circumvent the inaccessibility of human ocular tissues by generating patient-derived induced pluripotent stem cells (iPSC) [ 34 , 35 , 36 ]. Although only two iPSC lines carrying PAX6 variants have been generated to date [ 37 , 38 ], the growing ability of differentiation methods to develop a variety of iPSC-derived ocular organoids that can mimic the human optic cup, retina, cornea or lentoid bodies in vivo allows the study of oculogenesis in the early stages [ 35 , 39 , 40 , 41 ].…”

“…Alternatively, adult somatic cell reprogramming techniques circumvent the inaccessibility of human ocular tissues by generating patient-derived induced pluripotent stem cells (iPSC) [ 34 , 35 , 36 ]. Although only two iPSC lines carrying PAX6 variants have been generated to date [ 37 , 38 ], the growing ability of differentiation methods to develop a variety of iPSC-derived ocular organoids that can mimic the human optic cup, retina, cornea or lentoid bodies in vivo allows the study of oculogenesis in the early stages [ 35 , 39 , 40 , 41 ]. Therefore, the use of organoids as disease models opens the possibility of assessing splicing variants under more physiological conditions [ 42 ], as well as deepening the involvement of PAX6 alternative splicing in the development of different ocular structures.…”

Human Cellular Models for Retinal Disease

“…Subsequent patient-specific studies revealed that a disease phenotype could be observed in patient iPSC-derived retinal cells. 15,16 Although iPSC were initially produced from adult fibroblasts, they can now be produced from less invasive samples such as blood and urine, although there is no consensus on the preferred somatic cell source for iPSC derivation. The next breakthrough ushered in a new generation of retinal models, based on organoids that more closely replicate in vivo development.…”