Targeted In Utero Therapeutics Delivery System for Precise Gene Editing

Targeted lipid nanoparticles (LNPs) that can deliver mRNA-based gene editing therapeutics to hematopoietic stem cells (HSCs) in utero
Problem:
Monogenic blood diseases, including sickle cell disease and / thalassemia, are among the most prevalent genetic conditions worldwide, causing significant pediatric morbidity with complications like painful crises, severe anemia, and sometimes fetal demise. mRNA-based therapies targeting HSCs, including ex vivo gene therapy, show promise but are costly ($2-3 million per dose), time-intensive, and require specialized infrastructure, limiting access in low-income countries. An alternative approach involves ionizable LNPs for in vivo gene editing, offering a simpler and potentially more affordable option. However, this method is currently limited to delivering reporter or gene-modifying cargos and testing in adult mouse models, where disease processes have matured.
Solution:
The invention introduces an LNP platform that enables in vivo gene editing of fetal HSCs and their progeny. When administered in utero, these engineered LNPs target HSCs in the fetal liver and deliver their mRNA cargo, embedding a therapeutic genetic edit that remains as the cells migrate into the bone marrow. This offers the potential mitigating long-term disease in both the hematopoietic niche and circulating blood supply.
Technology:
The design approach leverages fetal and developmental biology principles to overcome the typical barriers to delivering mRNA-LNPs to HSCs. By targeting HSCs while they reside in the liver, a more accessible delivery site than the bone marrow in postnatal life, the platform enables gene editing during the developmental stage when cells are more reachable for therapeutic intervention. The LNP is developed using C14-490 as the ionizable lipid, combined with cholesterol, phospholipids, and PEG-lipids. To achieve precise targeting, CD45 antibody fragments are attached to the surface of the LNPs, enabling efficient and specific gene editing of HSCs in utero.
Advantages:

The LNP platform offers safe, potent, and long-term gene modulation of HSCs in vivo
The targeted LNPs exhibit safe, durable, and potent gene editing of fetal HSCs in mice after a single intravenous injection
CD45 antibody conjugation increases size without loss in mRNA encapsulation efficiency
CD45 antibody conjugation increases LNP-mediated mRNA delivery in immortalized cells by 8-fold compared to untargeted LNPs
In fetal liver cells, CD45 antibody conjugation increases the transfection of HSCs in vivo by 7-fold compared to untargeted LNPs

Stage of Development:

Preclinical Discovery

(A)   Schematic of CD45-targeted LNPs being injected in utero to deliver gene-editing cargo to fetal liver HSCs, which migrate to the bone marrow and enable the lifelong production of edited blood cells
(B)   Schematic of untargeted LNP formulation that involves C14-490 ionizable lipid, DOPE, cholesterol, C14-PEG2K, and a C18-PEG2K-maleimide linker in organic phase mixed via a microfluidic device with designated RNA cargo in citric acid buffer
(C)   Schematic of targeted LNP formulation that involves CD45 F(ab)’2 antibody generation and conjugation with untargeted LNP
(D)   Graph comparing the size of untargeted LNPs (blue) and targeted LNPs (pink)
(E)   Graph comparing the polydispersity of untargeted LNPs (blue) and targeted LNPs (pink)
(F)   Graph comparing the encapsulation efficiency of untargeted LNPs (blue) and targeted LNPs (pink)
Intellectual Property: