Recapitulating and Correcting Marfan Syndrome in a Cellular Model

Area of Science:

• Genetics
• Stem Cell Biology
• Biochemistry

Background:

• Marfan syndrome (MFS) is a genetic connective tissue disorder.
• Mutations in the FBN1 gene, encoding fibrillin-1, are the primary cause of MFS.
• Traditional animal models have limitations for studying late-onset MFS.

Purpose of the Study:

• To investigate the cellular and molecular mechanisms of MFS using human pluripotent stem cells (PSCs).
• To establish both gain-of-function and loss-of-function models for MFS using isogenic PSC lines.

Main Methods:

• Derived induced PSCs (iPSCs) from MFS patients and corrected the FBN1 mutation.
• Generated FBN1 knockout human embryonic stem cells (ESCs) as a loss-of-function model.
• Differentiated PSCs into mesenchymal stem cells and vascular smooth muscle cells for functional assays.

Main Results:

• FBN1-mutant mesenchymal stem cells showed reduced osteogenic differentiation and microfibril formation.
• Vascular smooth muscle cells from FBN1-mutant iPSCs exhibited decreased contractility and Ca2+ influx.
• Transcriptomic analysis supported the observed phenotypic changes.

Conclusions:

• Human PSCs provide a valuable in vitro model for studying MFS pathogenesis.
• Both gain-of-function and loss-of-function studies confirm the role of FBN1 mutations in MFS phenotypes.
• The study elucidates FBN1's critical role in connective tissue, bone, and vascular development.