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Biology subjects

Cozzone, A.

Publications and source records attributed to Cozzone, A..

2 recordsLinked to original sources

Enhanced lentiviral gene delivery to mammalian cells via paired cell surface and viral envelope engineering

Lentiviral vectors that facilitate gene delivery to desired cell types have been widely used in routine laboratory research and therapeutic cell engineering. However, the lack of proper entry receptors on many cell types often results in poor gene delivery. Here, we present a simple paired virus-cell engineering approach that promotes lentiviral gene delivery into mammalian cells. Lentiviruses are dual-pseudotyped with VSV-G and a chimeric envelope protein specifically recognizing a small molecule fluorescein (FITC-Env), and target cells are transiently labelled with FITC to create surrogate receptors for lentivirus attachment. The synthetic interaction between FITC-labeled cells and FITC-binding LVs enables efficient LV docking, viral entry and stable transgene expression in a range of mammalian cell lines and primary T cells. We showed that this approach enabled efficient delivery of a CD19-targeted chimeric antigen receptor (CAR) into naive human T cells that are naturally refractory to conventional VSV-G LVs, which upon activation rapidly eradicated CD19+ leukemic cells. This paired cell surface and virus envelope engineering approach may serve as a universal method for engineering synthetic virus-cell interactions to improve lentiviral gene delivery to mammalian cells.

bioengineering↗

Directed evolution-based discovery of ligands for in vivo restimulation of CAR-T cells

Chimeric antigen receptor (CAR) T cell therapy targeting CD19 elicits remarkable clinical efficacy in B-cell malignancies, but many patients relapse due to failed expansion and/or progressive loss of CAR-T cells. We recently reported a strategy to potently restimulate CAR-T cells in vivo, enhancing their functionality by administration of a vaccine-like stimulus comprised of surrogate peptide ligands for a CAR linked to a lymph node-targeting amphiphilic PEG-lipid (termed CAR-T-vax). Here, we demonstrate a general strategy to generate and optimize peptide mimotopes enabling CAR-T-vax generation for any CAR. Using the clinical CD19 CAR (FMC63) as a test case, we employed yeast surface display to identify peptide binders to soluble IgG versions of FMC63, which were subsequently affinity matured by directed evolution. CAR-T vaccines using these optimized mimotopes triggered marked expansion and memory development of CD19 CAR-T cells in both syngeneic and humanized mouse models of B-ALL/Lymphoma, and enhanced control of disease progression. This approach thus enables vaccine boosting to be applied to any clinically relevant CAR-T cell product.

bioengineering↗