3 research outputs found
Maternal microchimerism and cell-mediated immune-modulation enhance engraftment following semi-allogenic intrauterine transplantation
10.1096/fj.202002185RRFASEB JOURNAL35
Stable human FIX expression after 0.9G intrauterine gene transfer of self-complementary adeno-associated viral vector 5 and 8 in macaques
Intrauterine gene transfer (IUGT) offers ontological advantages including immune naiveté mediating tolerance to the vector and transgenic products, and effecting a cure before development of irreversible pathology. Despite proof-of-principle in rodent models, expression efficacy with a therapeutic transgene has yet to be demonstrated in a preclinical nonhuman primate (NHP) model. We aimed to determine the efficacy of human Factor IX (hFIX) expression after adeno-associated-viral (AAV)-mediated IUGT in NHP. We injected 1.0-1.95 × 10 vector genomes (vg)/kg of self-complementary (sc) AAV5 and 8 with a LP1-driven hFIX transgene intravenously in 0.9G late gestation NHP fetuses, leading to widespread transduction with liver tropism. Liver-specific hFIX expression was stably maintained between 8 and 112% of normal activity in injected offspring followed up for 2-22 months. AAV8 induced higher hFIX expression (P = 0.005) and milder immune response than AAV5. Random hepatocellular integration was found with no hotspots. Transplacental spread led to low-level maternal tissue transduction, without evidence of immunotoxicity or germline transduction in maternal oocytes. A single intravenous injection of scAAV-LP1-hFIXco to NHP fetuses in late-gestation produced sustained clinically-relevant levels of hFIX with liver-specific expression and a non-neutralizing immune response. These data are encouraging for conditions where gene transfer has the potential to avert perinatal death and long-term irreversible sequelae
Ionizable Lipid Nanoparticles for Therapeutic Base Editing of Congenital Brain Disease
Delivery of mRNA-based therapeutics to the perinatal
brain holds
great potential in treating congenital brain diseases. However, nonviral
delivery platforms that facilitate nucleic acid delivery in this environment
have yet to be rigorously studied. Here, we screen a diverse library
of ionizable lipid nanoparticles (LNPs) via intracerebroventricular
(ICV) injection in both fetal and neonatal mice and identify an LNP
formulation with greater functional mRNA delivery in the perinatal
brain than an FDA-approved industry standard LNP. Following in vitro optimization of the top-performing LNP (C3 LNP)
for codelivery of an adenine base editing platform, we improve the
biochemical phenotype of a lysosomal storage disease in the neonatal
mouse brain, exhibit proof-of-principle mRNA brain transfection in vivo in a fetal nonhuman primate model, and demonstrate
the translational potential of C3 LNPs ex vivo in
human patient-derived brain tissues. These LNPs may provide a clinically
translatable platform for in utero and postnatal
mRNA therapies including gene editing in the brain