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Selleri, S.

Publications and source records attributed to Selleri, S..

3 recordsLinked to original sources

Off-the-Shelf Engineered Liver Tissue Reverses Acute Liver Failure Without Immunosuppression

There is an urgent need for effective solutions to replace liver functions in patients with acute liver failure (ALF). We describe here a human engineered liver tissue composed of induced pluripotent stem cell (iPSC)-derived liver organoids encapsulated within a non-degradable biomaterial. Unlike most stem cell-derived products, this encapsulated liver tissue (ELT) achieves functional maturation during manufacturing. When transiently implanted into the peritoneal cavity of immunocompetent mice with ALF, the human ELT improves survival, treats hepatic encephalopathy and promotes liver regeneration, without requiring immunosuppression. Based on robust processes and designed to overcome challenges such as foreign body reaction, loss of function and cryopreservation, the ELT does not require vascularization and provides immediate and long-lasting functional replacement. Once the liver regenerated, the ELT is explanted, leaving the subjects cured. Macroencapsulation prevents rejection by shielding the organoids from the host immune system, and minimizes the risk of tumorigenicity. The data shown demonstrate the ELTs potential to be developed into a safe and effective off-the-shelf treatment that, if validated in upcoming clinical trials, could replace liver transplantation for many patients with ALF.

bioengineering↗

Leveraging complex interactions between signaling pathways involved in liver development to robustly improve the maturity and yield of pluripotent stem cell-derived hepatocytes

Pluripotent stem cell (PSC)-derived hepatocyte-like cells (HLC) have shown great potential as an alternative to primary human hepatocytes (PHH) for in vitro modeling. Several differentiation protocols have been described to direct PSC towards the hepatic fate, although the resulting HLC have shown more a fetal than adult phenotype. Here, by leveraging recent knowledge of the signaling pathways involved in liver development, we describe a robust, scalable protocol that allows to consistently generate high-quality HLC from both ESC and iPSC. Such HLC are comparable to adult PHH in terms of key mature liver functions and proved suitable to assess drug hepatotoxicity, as a proof of concept of their potential as a physiologically representative alternative for in vitro modeling.

developmental biology↗

Efficient and robust NK-Cell transduction with Baboon Envelope pseudotyped lentivector: a major tool for immunotherapy

NK-cell resistance to transduction is a major technical hurdle for developing NK-cell immunotherapy. By using Baboon envelope pseudotyped lentiviral vectors (BaEV-LVs) encoding eGFP, we obtained a transduction rate of 23.0{+/-}6.6% in freshly-isolated NK-cells (FI-NK) and 83.4{+/-}10.1% in NK-cells obtained from the NK-cell Activation and Expansion System (NKAES), even at low MOI, with a sustained transgene expression for at least 21 days. BaEV-LVs outperformed Vesicular Stomatitis Virus type-G (VSV-G)-, RD114-and Measles Virus (MV)-pseudotyped LVs (p<0.001). mRNA expression of both BaEV receptors, ASCT1 and ASCT2, was detected in FI-NK and NKAES, with much higher expression in NKAES. Transduction with BaEV-LVs encoding for CAR-CD22 resulted in robust CAR-expression on 44.2%{+/-}14.2% of NKAES cells, which allowed the specific killing of the NK-resistant pre-B-ALL-RS4;11 cell line. Using a larger vector, encoding a dual CD19/CD22-CAR separated by T2A, we were able to transduce and re-expand dual-CAR-expressing NKAES, even with low viral titer. These dual-CAR-NK efficiently and specifically killed both CD19KO-and CD22KO-RS4;11 cells, which may overcome antigen-loss escape in the clinical setting. Our results suggest that BaEV-LVs may efficiently enable NK-cell biological studies and translation of NK-cell-based immunotherapy to the clinic.

immunology↗