bioRxiv Science⌕ Search

Biology subjects

Vysotskiy, M.

Publications and source records attributed to Vysotskiy, M..

2 recordsLinked to original sources

LNP-mediated BCL11A Editing Corrects Sickling Phenotypes and Preserves HSPC Fitness Compared to Electroporation

Hemoglobinopathies, including sickle cell disease (SCD) and thalassemia syndromes, affect millions of individuals worldwide who have limited access to curative therapies. Autologous hematopoietic stem cell transplant following ex vivo CRISPR editing of the BCL11A erythroid enhancer reactivates fetal hemoglobin (HbF) and achieves an effective cure, but the resource constraints of clinically approved procedures for editing by electroporation (EP) severely limit widespread implementation. We directly compared the functional outcomes of EP delivery of Cas9 ribonucleoprotein with lipid nanoparticle (LNP) delivery of Cas9 mRNA in primary human HSPCs obtained from healthy HbAA donors and from patients with SCD. While higher editing rates are achieved with EP, LNP-treated HSPCs exhibited greater viability and cell yields that persisted throughout a multi-stage in vitro erythroid differentiation protocol. By day 20, the yield of mature red blood cells (CD71lowCD235ahigh) was lowest in the EP cohorts. Across treatment groups, we observed HbF induction proportional to indel frequency. LNP editing of SCD patient-derived HSPCs as low as 25% modified alleles still caused HbF production and reduced the propensity for sickling of in vitro differentiated RBCs. These findings highlight the critical trade-offs among manufacturing ease, delivery-associated toxicity, and functional performance across two modalities of therapeutic genome editing for hemoglobinopathies.

bioengineering↗

Integration of genetic, transcriptomic, and clinical data provides insight into 16p11.2 and 22q11.2 CNV genes

Deletions and duplications of the multigenic 16p11.2 and 22q11.2 copy number variants (CNVs) are associated with brain-related disorders including schizophrenia, intellectual disability, obesity, bipolar disorder, and autism spectrum disorder (ASD). The contribution of individual CNV genes to each of these phenotypes is unknown, as is the contribution of CNV genes to subtler health impacts. Hypothesizing that DNA copy number acts via RNA expression, we attempted a novel in silico fine-mapping approach in non-carriers using both GWAS and biobank data. We first asked whether expression level of a CNV gene impacts risk for a known brain-related phenotype(s). Using transcriptomic imputation, we tested for association within GWAS for schizophrenia, IQ, BMI, bipolar disorder, and ASD. We found individual genes in 16p11.2 associated with schizophrenia, BMI, and IQ (SPN), using conditional analysis to identify INO80E as the driver of schizophrenia, and SPN and INO80E as drivers of BMI. Second, we used a biobank containing electronic health data to compare the medical phenome of CNV carriers to controls within 700,000 individuals to investigate a spectrum of health effects, identifying novel and previously observed traits. Third, we used genotypes for over 48,000 biobank individuals to perform phenome-wide association studies between imputed expressions of 16p11.2 and 22q11.2 genes and over 1,500 health traits, finding seventeen significant gene-trait pairs, including psychosis (NPIPB11, SLX1B) and mood disorders (SCARF2), and overall enrichment of mental traits. Our results demonstrate how integration of genetic and clinical data aids in understanding CNV gene function, and implicate pleiotropy and multigenicity in CNV biology.

genetics↗