Restoration of β-globin expression with optimally designed lentiviral vector for β-thalassemia treatment in Chinese patients

Ouyang, W.; Dong, G.; Zhao, W.; Li, J.; Zhou, Z.; Yang, G.; Liu, R.; Li, Y.; Zhang, Q.; Du, X.; Sun, H.; Gu, Y.; Lai, Y.; Liu, S.; Liu, C.

doi:10.1101/2020.07.18.209759

bioRxiv · 10.1101/2020.07.18.209759

Restoration of β-globin expression with optimally designed lentiviral vector for β-thalassemia treatment in Chinese patients

Ouyang, W.·Dong, G.·Zhao, W.·Li, J.·Zhou, Z.·Yang, G.·Liu, R.·Li, Y.·Zhang, Q.·Du, X.·Sun, H.·Gu, Y.·Lai, Y.·Liu, S.·Liu, C.

View original source ↗Export metadata ↓

Abstract

{beta}-thalassemia is one of the most prevalent genetic diseases worldwide. The current treatment for {beta}-thalassemia is allogeneic hematopoietic stem cell transplantation (HSCT), which is limited due to lack of matched donors. Gene therapy has been developed as an alternative therapeutic option for transfusion-ependent {beta}-thalassemia (TDT). However, successful gene therapy for {beta}-thalassemia patients in China has not been reported. Here we present the results of preclinical studies of an optimally designed LV named LentiHBBT87Q in hematopoietic stem cells (HSCs) derived from Chinese TDT patients. LentiHBBT87Q was selected from a series of LVs with optimized backbone and de novo cloning strategy. It contains an exogenous T87Q {beta}-globin gene (HBBT87Q) driven by a specific reconstituted locus control region (rLCR) and efficiently express HBB mRNA and HBB protein in erythroblasts derived from cord blood (CB) HSCs. To facilitate clinical transformation, we manufactured clinical grade LentiHBBT87Q (cLentiHBBT87Q) and optimized its transduction procedure. Importantly, transduction of cLentiHBBT87Qrestored expression of HBB monomer and adult hemoglobin (HbA) tetramer to relatively normal level in erythroblasts from bone marrow (BM) HSCs of Chinese TDT patients, that carry the most common mutation types and cover various genotypes, including {beta}0/{beta}0. Furthermore, viral integration sites (VIS) of cLentiHBBT87Q were similar to other LVs safely used in previous clinical trials and the associated risk of tumorigenesis was not observed in cLentiHBBT87Q transduced HSCs through comprehensive analysis. Taken together, we have engineered the cLentiHBBT87Q that can restore {beta}-globin expression in the HSCs-derived erythroblasts of Chinese TDT patients with minimal risk on tumorigenesis, providing a favorable starting point for future clinical application.

Source connections

Published article ↗

Explore related subjects

cell biology Preprint

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

Ouyang, W., Dong, G., Zhao, W., Li, J., Zhou, Z., Yang, G., Liu, R., Li, Y., Zhang, Q., Du, X., Sun, H., Gu, Y., Lai, Y., Liu, S., Liu, C.. 2020-07-21. Restoration of β-globin expression with optimally designed lentiviral vector for β-thalassemia treatment in Chinese patients. https://doi.org/10.1101/2020.07.18.209759

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

bioRxiv2026

Functional characterization of Rho GTPase activating proteins SYDE1 and SYDE2

The human genome encodes more than 60 proteins containing Rho GTPase activating protein (RhoGAP) domains, many of which remain understudied with respect to their target specificity and biological roles. SYDE1 and SYDE2 are two such orphan RhoGAPs, for which there are few studies characterizing their biochemical and cellular functions and conflicting reports identifying their cognate GTPases. We previously identified SYDE1 and SYDE2 in a screen for substrates of the c-Jun N-terminal kinases. Here, we show that SYDE1 and SYDE2 are preferentially phosphorylated by JNK1 relative to other mitogen-activated protein kinases (MAPKs) at sites proximal to a kinase docking region. Purified SYDE1 and SYDE2 are shown to have significant catalytic GAP activity toward RhoA, Rac1, and Cdc42. However, neither up- nor down-regulation of SYDE1/2 expression leads to detectable changes in bulk GTP loading of any of these GTPases. Nevertheless, we demonstrate that SYDE1 and SYDE2, in a partially GAP-dependent manner, increase cell spreading and number of focal adhesions, and promote more directionally persistent migration in HEK293 cells. Together, these findings establish SYDE1 and SYDE2 as robust JNK substrates with catalytic activity toward a set of Rho GTPases and reveal basic functions of SYDE1 and SYDE2 in regulating cell morphology, adhesion, and migration.

cell biology↗

bioRxiv2026

The filopodial scaffold polyphosphate dictates cell adhesion-versus-invasion decisions

Inorganic polyphosphate (polyP) is an ancient polymer conserved across all life, serving cell type and location specific functions in every major compartment. Yet its role at the plasma membrane, where it accumulates to peak levels in many primary cells, is largely unknown. Here we identify polyP as a stabilizing component of filopodia, actin based membrane protrusions that govern cell adhesion, contact inhibition, and chemotaxis. Elevating cellular polyP increases filopodial stability and enhances cell adhesion, whereas reducing polyP accelerates filopodial disassembly and promotes cell migration. Mechanistically, we find that polyP acts as a structural filopodial scaffold, recruiting and organizing IRSp53, a membrane curvature inducing protein. We show that metastatic fibroblasts and breast cancer organoids carry markedly reduced and intracellularly reorganized polyP levels relative to their non transformed counterparts. Restoring endogenous polyP via lipid nanoparticle delivery suppresses their invasive phenotypes and reverses prometastatic gene expression signatures, implicating polyP as a primordial tumor suppressor.

cell biology↗

bioRxiv2026

Mitochondrial transfer mediates metabolic communication between beta cells and islet macrophages

Pancreatic islet macrophages support islet homeostasis and adapt their metabolic program in response to environmental cues, including beta cell released factors. Intercellular mitochondrial transfer is a biological process that modulates cellular responses. To test whether beta cells, which are strongly secretory, transfer mitochondria to islet macrophages, we generated mice with beta cell-specific expression of mitochondrial GFP (PhAMfloxIns1Cre). We demonstrate that beta cells transfer mitochondria to islet macrophages in vivo and in vitro. Diabetogenic stressors did not alter the frequency of mitochondrial transfer and macrophages containing beta cell-derived GFP exhibit increased protein synthesis rates. RNA-seq identified upregulation of activity-regulated cytoskeleton associated protein (Arc) in macrophages receiving beta cell-derived mitochondria, while disruption of actin cytoskeleton dynamics prevented mitochondrial transfer. Together, these findings identify mitochondrial transfer as a previously unrecognized mechanism of beta cell-macrophage communication that may contribute to islet homeostasis and immune regulation.

cell biology↗