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Biology subjects

van den Hil, F. E.

Publications and source records attributed to van den Hil, F. E..

3 recordsLinked to original sources

Solid tumor-on-chip model for efficacy and safety assessment of CAR-T cell therapy

The non-clinical assessment of CAR-T cells demands innovative models that are capable of predicting safety and efficacy in the clinical setting. Here, we present a novel solid tumor-on-chip model that allows CAR-T cell perfusion and integrates the vasculature and tumor lesions to recapitulate key events of CAR-T cell performance including extravasation, tumor infiltration and cytokine release. We assessed CAR-T cells targeting the ROR1 antigen against tumor aggregates that were derived from a breast cancer cell line and primary breast cancer organoids. The data show the temporal kinetic of ROR1 CAR-T cell migration and expansion, lytic activity and cytokine production over the course of 8 days, and reveal a correlation between anti-tumor efficacy and ROR1 antigen density on tumor cells. CAR-modified T cells extravasated faster, infiltrated tumor lesions stronger, persisted longer and in higher numbers than non-CAR modified T cells. Intriguingly, we detected cytokine release levels and kinetics typically observed in patients who developed cytokine release syndrome, and administered dasatinib as a pharmacologic OFF switch to control this inflammatory response. The data illustrate the ability of this tumor-on-chip platform to assess parameters associated withherapeutic outcome and the potential to aid in patient stratification and monitoring of CAR-T cell therapy.

bioengineering↗

Tissue microenvironment dictates the state of human induced pluripotent stem cell-derived endothelial cells of distinct developmental origin in 3D cardiac microtissues

Each tissue and organ in the body has its own type of vasculature. Here we demonstrate that organotypic vasculature for the heart can be recreated in a three-dimensional cardiac microtissue (MT) model composed of human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes (CMs), cardiac fibroblasts (CFs) and endothelial cells (ECs). ECs in cardiac MTs upregulated expression of markers enriched in human intramyocardial ECs (iECs), such as CD36, CLDN5, APLNR, NOTCH4, IGFBP3, ARHGAP18, which were previously identified in the single-cell RNA-seq dataset from the human fetal heart (6.5-7 weeks post coitum). We further show that the local microenvironment largely dictates the organ-specific identity of hiPSC-derived ECs: we compared ECs of different developmental origins derived from two distinct mesoderm subtypes (cardiac and paraxial mesoderm) and found that independent of whether the ECs were cardiac or paraxial mesoderm derived, they acquired similar identities upon integration into cardiac microtissues. This was confirmed by single-cell RNA-seq. Overall, the results indicated that whilst the initial gene profile of ECs was dictated by developmental origin, this could be modified by the local tissue environment such that the original identity was lost and the organotypic identity acquired through local environmental signals. This developmental "plasticity" in ECs has implications for multiple pathological and disease states.

developmental biology↗

ETV2 upregulation marks the specification of early cardiomyocytes and endothelial cells during co-differentiation

The ability to differentiate human induced pluripotent stem cells (hiPSCs) efficiently into defined cardiac lineages, such as cardiomyocytes and cardiac endothelial cells, is crucial to study human heart development and model cardiovascular diseases in vitro. The mechanisms underlying the specification of these cell types during human development are not well-understood which limits fine-tuning and broader application of cardiac model systems. Here, we used the expression of ETV2, a master regulator of hematoendothelial specification in mice, to identify functionally distinct subpopulations during the co-differentiation of endothelial cells and cardiomyocytes from hiPSCs. Targeted analysis of single-cell RNA sequencing data revealed differential ETV2 dynamics in the two lineages. A newly created fluorescent reporter line allowed us to identify early lineage-predisposed states and show that a transient ETV2-high state initiates the specification of endothelial cells. We further demonstrated, unexpectedly, that functional cardiomyocytes can originate from progenitors expressing ETV2 at a low level. Our study thus sheds light on the in vitro differentiation dynamics of two important cardiac lineages. SIGNIFICANCE STATEMENTIn vitro differentiation of cardiac cell types is of great importance for understanding heart development, disease modeling and future regenerative medicine. Currently, underlying molecular mechanisms are incompletely understood, which limits the efficiency and fine-tuning of present differentiation protocols. Here, we investigated the master regulator ETV2 and showed that its upregulation marks the specification of two cardiac cell types during co-differentiation. Using single-cell RNA-seq and a new fluorescent reporter line we identified lineage-predisposed subpopulations in the ETV2+ cells. We thus resolved ETV2 dynamics at the single-cell level in the context of in vitro human cardiac differentiation.

developmental biology↗