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Launspach, M.

Publications and source records attributed to Launspach, M..

2 recordsLinked to original sources

Personalized CRISPR Knock-In Cytokine Gene Therapy to Remodel the Tumor Microenvironment and Enhance CAR T Cell Therapy in Solid Tumors

The immunosuppressive tumor microenvironment (TME) remains a central barrier to effective immunotherapy in solid tumors. To address this, we developed a novel gene therapeutic strategy that enables localized remodeling of the TME via tumor-intrinsic cytokine expression. Central to this approach is CancerPAM, a multi-omics bioinformatics pipeline that identifies and ranks patient-specific, tumor-exclusive CRISPR-Cas9 knock-in sites with high specificity and integration efficiency. Using neuroblastoma--a pediatric solid tumor with a suppressive TME--as a model, we applied CancerPAM to sequencing data from cell lines and patients to identify optimal integration sites for pro-inflammatory cytokines (CXCL10, CXCL11, IFNG). CRISPR-mediated CXCL10 knock-in into tumor cells significantly enhanced CAR T cell infiltration and antitumor efficacy both in vitro and in vivo. In vivo, CXCL10-expressing tumors showed significantly increased early CAR T cell infiltration and prolonged survival compared to controls. CancerPAM rankings correlated strongly with target-site specificity and knock-in efficiency, validating its predictive performance. Our findings establish CancerPAM as a powerful tool for safe and effective CRISPR-based interventions and provide a conceptual framework for integrating cytokine-driven TME remodeling with cellular immunotherapies. This personalized strategy holds promise for enhancing CAR T cells and other immunotherapies across immune-refractory solid tumors.

bioengineering↗

Revisiting the need for mRNA nucleoside modification in CAR T cell engineering

mRNA-based chimeric antigen receptor (CAR)-T cells offer the promise of enhanced safety and simplified manufacturing. However, in vitro-transcribed (IVT) mRNA is known to trigger antiviral immune responses, inflammatory signaling, and apoptosis in transfected cells. To address these challenges and enable efficient IVT-mRNA expression, modified nucleosides, such as N1-methyl-pseudouridine (m1{Psi}), have become the gold standard for CAR-T cell production, albeit at increased cost. In this study, immune responses to IVT-mRNA were evaluated across five primary human cell types, including T-cells. Unexpectedly, T-cells, unlike other immune and non-immune cell types tested, exhibited no immune activation in response to unmodified mRNA. T-cell viability and cytokine secretion patterns remained unaffected, regardless of whether unmodified mRNA was delivered via lipid nanoparticles (LNPs) or electroporation. Furthermore, CAR expression levels in T-cells were not influenced by mRNA modification with m1{Psi} or 5-methoxy-uridine (5moU) nucleosides. The absence of nucleoside modifications did not compromise CAR-T cell cytotoxic potency, demonstrating that such modifications are not required for producing functional CAR-T cells. These findings eliminate the need for nucleoside modification in T-cell mRNA, simplifying and reducing the cost of CAR-T cell manufacturing while positioning IVT-mRNA as a highly efficient and minimally invasive tool for CAR-T cell engineering.

bioengineering↗