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Scholten, K.

Publications and source records attributed to Scholten, K..

4 recordsLinked to original sources

DNA-Dependent Protein Kinase Inhibitors PI-103 and Samotolisib Augment CRISPR/Cas9 Knockin Efficiency in Human T Cells

1.The adoptive cell transfer of ex vivo expanded tumor infiltrating lymphocytes (i.e., TIL therapy) is a promising clinical strategy and recently FDA approved for melanoma but has major limitations including that not all tumors are inflamed. Moreover, tumor-specific clones can be rare and in an exhausted state due to the suppressive tumor microenvironment. These obstacles can be overcome by engineering autologous peripheral blood T cells with pre-selected T cell receptors (TCRs) by viral vector-mediated gene insertion. While viral transduction is highly efficient, the insertional site is not specific and persistence of the T cells is oftentimes limited. In contrast, site-specific integration of the TCR into the TCR chain (TRAC) locus by CRISPR/Cas9 has been shown to enable more consistent and physiological levels of exogenous TCR expression coupled with superior persistence and tumor control in preclinical studies. Here, we sought to improve the efficiency of CRISPR/Cas9 mediated TCR knockin (KI) into the TRAC locus of primary human T cells. In addition to the previously reported DNA-dependent protein kinase inhibitor M3814, we demonstrate that PI-103 and samotolisib markedly increase KI efficiency in a process that is GMP-compatible, while CC-115 had a variable effect. Importantly, PI-103 and samotolisib do not negatively impact cell viability, fold-expansion nor T cell phenotype and we conclude that they are suitable for the generation of gene-modified T cells for clinical use.

bioengineering↗

Mutational and transcriptional landscape of pediatric B-cell precursor lymphoblastic lymphoma

Pediatric B-cell precursor (BCP) lymphoblastic malignancies are neoplasms with manifestation either in bone marrow/blood (BCP acute lymphoblastic leukemia, BCP-ALL) or less common in extramedullary tissue (BCP lymphoblastic lymphoma, BCP-LBL). Although both presentations are similar in morphology and immunophenotype molecular studies are virtually restricted to BCP-ALL so far. The lack of molecular studies on BCP-LBL is probably due to its rarity and the restriction to tiny, mostly formalin-fixed paraffin embedded (FFPE) tissues. Here we present the first comprehensive mutational and transcriptional analysis of what we consider the largest BCP-LBL cohort described to date (n=97). Whole exome sequencing indicates a mutational spectrum of BCP-LBL strikingly similar to that found in BCP-ALL. However, epigenetic modifiers were more frequently mutated in BCP-LBL, whereas BCP-ALL was more frequently affected by mutation in genes involved in B-cell development. Integrating copy number alterations, somatic mutations and gene expression by RNA-sequencing revealed virtually all molecular subtypes originally defined in BCP-ALL to be present in BCP-LBL too, with only 7% of lymphomas that were not assigned to a subtype. Therefore, the results here described may pave the way for molecular risk adapted treatment protocols for BCP-LBL patients. KeypointsComprehensive molecular characterization of B-cell precursor lymphoblastic lymphoma allows molecular subtyping analogous to leukemias Compared to leukemias, lymphomas show more alterations in epigenetic modifiers and less in B-cell development genes

cancer biology↗

Polymer Implantable Electrode Foundry: A shared resource for manufacturing polymer-based microelectrodes for neural interfaces

Large scale monitoring of neural activity at the single unit level can be achieved via electrophysiological recording using implanted microelectrodes. While neuroscience researchers have widely employed chronically implanted electrode-based interfaces for this purpose, a commonly encountered limitation is loss of highly resolved signals arising from immunological response over time. Next generation electrode-based interfaces improve longitudinal signal quality using the strategy of stabilizing the device-tissue interface with microelectrode arrays constructed from soft and flexible polymer materials. The limited availability of such polymer microelectrode arrays has restricted access to a small number of researchers able to build their own custom devices or who have developed specific collaborations with engineering researchers who can produce them. Here, a new technology resource model is introduced that seeks to widely increase access to polymer microelectrode arrays by the neuroscience research community. The Polymer Implantable Electrode (PIE) Foundry provides custom and standardized polymer microelectrode arrays as well as training and guidance on best-practices for implantation and chronic experiments.

neuroscience↗

Combination of NY-ESO-1-TCR-T-cells coengineered to secrete SiRPalpha decoys with anti-tumor antibodies to augment macrophage phagocytosis

The adoptive transfer of T cell receptor (TCR)-engineered T cells (ACT) targeting the HLA-A2 restricted cancer-testis epitope NY-ESO-1157-165 (A2/NY) has yielded favorable clinical responses against a variety of cancers. Two promising approaches to improve ACT efficacy are TCR affinity-optimization and combinatorial treatment strategies to reprogram the tumor microenvironment (TME). By computational design, we previously developed a panel of affinity-enhanced A2/NY-TCRs. Here, we have demonstrated improved tumor control and engraftment by T cells gene-modified to express one such TCR comprising a single amino acid replacement in CDR3{beta} (A97L). To harness macrophages in the TME, we coengineered TCR-T cells to constitutively or inducibly secrete a high-affinity signal regulatory protein alpha (SiRP) decoy (CV1) to block the CD47 dont eat me signal. We demonstrated better control of tumor outgrowth by CV1-Fc coengineered TCR-T cells but in subcutaneous xenograft tumor models we observed depletion of both CV1-Fc and CV1 coengineered T cells. Importantly, CV1 coengineered T cells were not depleted by human macrophages in vitro. Moreover, Avelumab and Cetuximab enhanced macrophage-mediated phagocytosis in vitro in the presence of CV1, and augmented tumor control upon ACT. Taken together, our study indicates important clinical promise for harnessing macrophages by combining CV1 coengineered TCR-T cells with tumor-targeting monoclonal antibodies.

bioengineering↗