PERSONALIZED MEDICINE FOR CONGENITAL MUSCULAR DYSTROPHIES: DEVELOPMENT AND VALIDATION OF ADVANCED TREATMENTS FOR COLLAGEN VI DEFICIENCY
PROJECT SUMMARY
Main Objective
The main purpose of this project is to advance personalized medicine for collagen VI-related congenital muscular dystrophies (COL6-RD) through three main areas:
i) In vitro and in vivo validation of previously developed gene-editing strategies, including antisense oligonucleotides (ASOs) and base editors.
ii) Development of new therapeutic tools targeting splicing mutations.
iii) Investigation of novel pharmacological therapeutic targets using the Col6a1 Ki G292R animal model.
Work Plan and Methodology
The project is divided into three specific objectives, each with its corresponding methodology:
1. Preclinical Validation of Therapeutic Strategies for Point Mutations
In vivo antisense oligonucleotides (ASOs):
Following the successful intellectual property protection of the candidate ASOs through a PCT patent application, their efficacy will be validated in the Col6a1 Ki G292R mouse model using intramuscular and intravenous injections.
Tissue biodistribution and silencing of the mutant allele will be assessed using Splint PCR and digital PCR. Restoration of collagen VI will be evaluated by Western blotting and immunofluorescence, together with an assessment of toxicity and biocompatibility.
Optimization of base editors (ABE8e) for the c.877G>A mutation:
Building on the optimization of adenine base editor mRNA—which resulted in a 30% increase in the healthy allele and correction of the extracellular matrix pattern in vitro—new transfection and nucleofection conditions will be investigated in fibroblasts to increase the correction rate while monitoring genotoxicity and unintended genomic effects.
Delivery systems:
Research will continue into the potential of lipid nanoparticles known as Quatsomes (QS), which have demonstrated the ability to reach different muscle groups following intravenous administration.
Their performance will be investigated alongside other delivery agents and commercially available lipid nanoparticles (LNPs) using IVIS imaging, flow cytometry, and digital PCR.
2. Development of Therapeutic Strategies for Splicing Mutations
A previously unreported intronic mutation (c.859-10T>A), which causes the inclusion of a 159-nucleotide pseudoexon and disrupts the triple helix of the alpha-1 chain, will be characterized in detail.
A specific antibody will be generated to detect the pseudoexon. In parallel, ASOs and base editors will be designed to modify splicing in order to reduce or eliminate its expression.
3. Investigation of Pharmacological Therapeutic Targets and Pathophysiological Mechanisms
Since the mouse model exhibits increased diaphragm fibrosis from two months of age onwards, muscle regenerative capacity will be investigated by inducing muscle damage with cardiotoxin.
The involvement of the TGF-β signaling pathway will also be studied by analyzing markers including Smad3, fibronectin, and periostin.
The aim is to determine whether these alterations are common features of COL6-RD and to validate the potential use of antifibrotic drugs as complementary treatments alongside gene therapy.
Milestones Achieved and Rationale
This project builds on successful previous results, most notably the intellectual property protection of the developed ASOs through patent application PCT/EP2024/067949, a critical step towards clinical translation and their potential future application in humans.
In addition, established methodologies are already in place for gene editing using ABE8e and for delivery using Quatsomes, supporting the technical feasibility of the proposed research.
Project Duration
2025–2027 (2 years)
Research Location
Hospital Sant Joan de Déu, in collaboration with UCL Business Ltd, CIEMAT, ETH Zurich, and ICMAB.
Researchers Involved
Dr. Cecilia Jiménez Mallebrera
Research Group Coordinator
Collaborators:
Dr. Paula Río — CIEMAT, Madrid
Dr. Jacob E. Corn — ETH Zurich, Zurich
Budget
€87,038.60
This includes €79,126 in personnel costs for a full-time research assistant, plus 10% in indirect costs.