Fecha de publicación: 06/11/2024 Fuente: Biomolecules - Revista científica (MDPI) Biomolecules, Vol. 14, Pages 1412: Restored Collagen VI Microfilaments Network in the Extracellular Matrix of CRISPR-Edited Ullrich Congenital Muscular Dystrophy Fibroblasts
Biomolecules doi: 10.3390/biom14111412
Authors:
Daniela Benati
Eleonora Cattin
Federico Corradi
Tommaso Ferrari
Eleonora Pedrazzoli
Clarissa Patrizi
Matteo Marchionni
Roberto Bertorelli
Veronica De Sanctis
Luciano Merlini
Alessandra Ferlini
Patrizia Sabatelli
Francesca Gualandi
Alessandra Recchia

Collagen VI is an essential component of the extracellular matrix (ECM) composed by α1, α2 and α3 chains and encoded by COL6A1, COL6A2 and COL6A3 genes. Dominant negative pathogenic variants in COL6A genes result in defects in collagen VI protein and are implicated in the pathogenesis of muscular diseases, including Ullrich congenital muscular dystrophy (UCMD). Here, we designed a CRISPR genome editing strategy to tackle a dominant heterozygous deletion c.824_838del in exon 9 of the COL6A1 gene, causing a lack of secreted collagen VI in a patient’s dermal fibroblasts. The evaluation of efficiency and specificity of gene editing in treating patient’s fibroblasts revealed the 32% efficiency of editing the mutated allele but negligible editing of the wild-type allele. CRISPR-treated UCMD skin fibroblasts rescued the secretion of collagen VI in the ECM, which restored the ultrastructure of the collagen VI microfibril network. By using normal melanocytes as surrogates of muscle cells, we found that collagen VI secreted by the corrected patient’s skin fibroblasts recovered the anchorage to the cell surface, pointing to a functional improvement of the protein properties. These results support the application of the CRISPR editing approach to knock out COL6A1 mutated alleles and rescue the UCMD phenotype in patient-derived fibroblasts.