A preliminary study on the mechanism of skeletal abnormalities in Turner syndrome using inducing pluripotent stem cells (iPS)-based disease models

Abstract

Osteoporosis represent one of main characteristics of Turner syndrome (TS), a rare diseases caused by aberrant deletion of X chromosomes, however, the underlying pathological mechanism remains unknown yet. In this study, we used pluripotent stem cells (iPSCs) derived from a Turner syndrome patient and a health control to induce functional osteoblasts and osteoclasts, in order to compare their difference in these two differentiation. We successfully produced functional osteoblasts and osteoclasts from iPSCs through embryoid bodies (EBs) and mesoderm stages, as demonstrated obvious mineralized nodules and multi-nuclear giant cells with positive tartrate-resistant acid phosphatase (TRAP) staining, and significant up-regulated differentiation marker genes. Interestingly, we found that there was no significant difference in phenotype and marker genes expression between osteoblasts from Turner syndrome and healthy control iPSCs. In contrast, Turner syndrome showed increased osteoclastogenesis compared to the healthy control indicating higher frequency of multi-nuclear TRAP staining cells and elevated osteoclast marker genes TRAP, MMP9, CA2, OSCAR. Therefore, our results suggest that the low bone density of Turner syndrome patients may be caused by aberrant osteoclast differentiation, and further investigation towards osteoclast function under Turner syndrome is deserved.

Efficient generation of osteoclasts from human induced pluripotent stem cells and functional investigations of lethal CLCN7-related osteopetrosis

“…In 2017, Chen et al ( 12 ) presented their osteoclast differentiation protocol, which includes only one single monocyte harvesting step and required up to six cytokines and supplement additives in four differentiation media. Finally, Cui et al ( 11 ) published a differentiation approach in 2019 using three different differentiation media based on expensive STEMdiff APEL 2 medium supplemented with up to eight cytokines and small molecules. Furthermore, the protocol does not include a monocyte production step, lasts up to 5 weeks, and the differentiation efficiency of 1.5% is low.…”

“…Several protocols for differentiation of hiPSCs into macrophages and osteoclasts have been published, all of which rely on the formation of embryoid bodies for mesodermal specification and the induction of hematopoiesis. (10)(11)(12)(13)(14)(15) However, the combination of cytokines, their concentrations, and the media used vary between the existing protocols, which can have a strong impact on the outcome and costs of the experiments. Furthermore, the exact yield of hiPSC-osteoclasts and their characteristics have not been described in detail.…”

A Turner Syndrome Case With Primary Amenorrhea Detected To Have Distal Radius Fracture And Severe Osteoporosis

“…Ergenlik döneminde hipoöstrojenizm nedeniyle kemik mineralizasyonu düşük olan kadınlarda osteoporoz (OP) riski artmaktadır. Gecikmiş ergenlik ve östrojen eksikliği TS'de OP oluşumunda belirleyici faktörlerden birkaçıdır ancak bir iç kemik defekti olup olmadığı hâlâ belirsizdir (2,3) . (3) .…”

“…Gecikmiş ergenlik ve östrojen eksikliği TS'de OP oluşumunda belirleyici faktörlerden birkaçıdır ancak bir iç kemik defekti olup olmadığı hâlâ belirsizdir (2,3) . (3) . Biz de olgumuza, bir bifosfanat olan risedronik asit reçete ederek, hastayı osteoporoz polikliniğimizde takibe aldık.…”

Versatility of Induced Pluripotent Stem Cells (iPSCs) for Improving the Knowledge on Musculoskeletal Diseases

“…To our knowledge, there are no studies modeling osteoporosis per se but rather modeling rare diseases where osteoporosis is part of their clinical manifestation. That is the case of the iPSCs generated from patients with Turner syndrome (TS) [ 79 ], a rare disease caused by a monosomy X. TS and healthy iPSCs were differentiated into osteoblasts and osteoclasts, with abnormal gene expression in TS iPSC-osteoclasts. The knowledge gained from studies on OI can also provide clues about the genetics of osteoporosis [ 24 ].…”