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Bi-directional gene activation and repression promote ASC differentiation and enhance bone healing in osteoporotic rats.

ABSTRACT: Calvarial bone healing is challenging, especially for individuals with osteoporosis because stem cells from osteoporotic patients are highly prone to adipogenic differentiation. Based on previous findings that chondrogenic induction of adipose-derived stem cells (ASCs) can augment calvarial bone healing, we hypothesized that activating chondroinductive Sox Trio genes (Sox5, Sox6, Sox9) and repressing adipoinductive genes (C/ebp-α, Ppar-γ) in osteoporotic ASCs can reprogram cell differentiation and improve calvarial bone healing after implantation. However, simultaneous gene activation and repression in ASCs is difficult. To tackle this problem, we built a CRISPR-BiD system for bi-directional gene regulation. Specifically, we built a CRISPR-AceTran system that exploited both histone acetylation and transcription activation for synergistic Sox Trio activation. We also developed a CRISPR interference (CRISPRi) system that exploited DNA methylation for repression of adipoinductive genes. We combined CRISPR-AceTran and CRISPRi to form the CRISPR-BiD system, which harnessed three mechanisms (transcription activation, histone acetylation, and DNA methylation). After delivery into osteoporotic rat ASCs, CRISPR-BiD significantly enhanced chondrogenesis and in vitro cartilage formation. Implantation of the engineered osteoporotic ASCs into critical-sized calvarial bone defects significantly improved bone healing in osteoporotic rats. These results implicated the potential of the CRISPR-BiD system for bi-directional regulation of cell fate and regenerative medicine.

SUBMITTER: Truong VA

PROVIDER: S-EPMC8753367 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature

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Bi-directional gene activation and repression promote ASC differentiation and enhance bone healing in osteoporotic rats.

Truong Vu Anh VA Lin Ya-Hui YH Nguyen Nuong Thi Kieu NTK Hsu Mu-Nung MN Pham Nam Ngoc NN Chang Yi-Hao YH Chang Chin-Wei CW Shen Chih-Che CC Lee Hsiang-Sheng HS Lai Po-Liang PL Parfyonova Yelena V YV Menshikov Mikhail M Wu Jaw-Ching JC Chang Yu-Han YH Hu Yu-Chen YC

Molecular therapy : the journal of the American Society of Gene Therapy 20210825 1

Calvarial bone healing is challenging, especially for individuals with osteoporosis because stem cells from osteoporotic patients are highly prone to adipogenic differentiation. Based on previous findings that chondrogenic induction of adipose-derived stem cells (ASCs) can augment calvarial bone healing, we hypothesized that activating chondroinductive Sox Trio genes (Sox5, Sox6, Sox9) and repressing adipoinductive genes (C/ebp-α, Ppar-γ) in osteoporotic ASCs can reprogram cell differentiation a ...[more]

PMID: 34450254

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Bi-directional gene activation and repression promote ASC differentiation and enhance bone healing in osteoporotic rats.

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Bi-directional gene activation and repression promote ASC differentiation and enhance bone healing in osteoporotic rats.

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