Biology subjects

Korving, J.

Publications and source records attributed to Korving, J..

5 recordsLinked to original sources

bioRxiv2025

Human embryo implantation involves Syncytin-2/MFSD2A-mediated heterokaryon formation with maternal endometrium

Human embryo implantation involves attachment of the blastocyst to the endometrial epithelium to subsequently gain access to the underlying stromal compartment. The blastocyst is believed to cross the epithelium either by migration through, or upon apoptosis of, the endometrial epithelial cell layer. Yet, how the blastocyst exactly traverses the endometrial epithelium remains unknown. Here, we describe an in vitro implantation model of human blastoids and hormonally matured endometrial organoids amenable to high-resolution live imaging. We demonstrate that the initial step of implantation is mediated by the direct fusion of blastoid cells with endometrial epithelial cells. Blastoids express the fusion proteins Syncytin-1 and -2, while the endometrial epithelium mainly expresses the fusion co-receptor for Syncytin-2, called MFSD2A. CRISPR-induced loss of MFSD2A in the endometrial epithelium prevents blastoids from attaching and abolishes fusion. Together, these findings support a model in which fetal-maternal cell fusion constitutes the critical initiating mechanism of human embryo implantation, with endometrial MFSD2A playing an indispensable role in this process.

developmental biology↗

bioRxiv2025

Scaling of mouse somitogenesis by coupling of cell cycle to segmentation clock oscillations

While scaling developmental processes is fundamental to maintaining robust tissue patterning, the mechanisms underlying this process are enigmatic. Somitogenesis, the periodic segmentation of growing mesodermal tissue in vertebrate embryos1, involves precise scaling with the unsegmented presomitic mesoderm (PSM) over developmental time and under perturbation2-4. Somitogenesis is spatiotemporally regulated by FGF and Wnt morphogen gradients and the segmentation clock -- oscillations in Notch, Wnt, and FGF signalling5-7. Here, we find that cell proliferation is distributed throughout the oscillating PSM. Long-term single-cell tracking in mouse embryo tails uncovered a correlation between cell cycle progression and the segmentation clock, with microfluidics-based entrainment indicating coupling between the cell cycle and signalling oscillations, likely through S-phase inducing Cyclins. A theoretical model suggests this coupling ensures uniform PSM growth, uniform morphogen dilution and precise somite formation, which we validated experimentally by blocking cell proliferation. Our findings reveal that coupling cell proliferation to signalling oscillations is crucial for robust somitogenesis and precise somite scaling.

developmental biology↗

bioRxiv2022

Druggable Growth Dependencies and Tumor Evolution Analysis in Patient-Derived Organoids of Neuroendocrine Cancer

Neuroendocrine neoplasms (NENs) comprise well-differentiated neuroendocrine tumors and poorly-differentiated carcinomas. Treatment options for patients with NENs are limited, in part due to lack of accurate models. To address this need we established the first patient-derived tumor organoids (PDTOs) from pulmonary neuroendocrine tumors and derived PDTOs from an understudied NEN subtype, large cell neuroendocrine carcinoma (LCNEC). PDTOs maintain the gene expression patterns, intra-tumoral heterogeneity, and evolutionary processes of parental tumors. Through drug sensitivity analyses, we uncover therapeutic sensitivities to an inhibitor of NAD salvage biosynthesis and to an inhibitor of BCL-2. Finally, we identify a dependency on EGF in pulmonary neuroendocrine tumor PDTOs. Consistent with these findings, analysis of an independent cohort showed that approximately 50% of pulmonary neuroendocrine tumors expressed EGFR. This study identifies a potentially actionable vulnerability for a subset of NENs, and further highlights the utility of these novel PDTO models for the study of NENs. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=188 HEIGHT=200 SRC="FIGDIR/small/514549v1_ufig1.gif" ALT="Figure 1"> View larger version (57K): org.highwire.dtl.DTLVardef@14bed0borg.highwire.dtl.DTLVardef@1b7791forg.highwire.dtl.DTLVardef@7120a6org.highwire.dtl.DTLVardef@116b21d_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_LIPDTOs of pulmonary NETs and LCNEC were established C_LIO_LIPDTOs recapitulate intra-tumoral heterogeneity and evolution of parental tumors C_LIO_LIDrug assays reveal therapeutic vulnerabilities and biomarkers C_LIO_LIPulmonary NET PDTOs are dependent on EGF C_LI

cancer biology↗

bioRxiv2019

Polar-like trophoblast stem cells form an embryonic-abembryonic axis in blastoids.

The early mammalian conceptus (blastocyst) comprises an outer trophoblast globe that forms an axis originating from the inner embryonic cells. From the mouse conceptus, Trophoblast stem cells (TSCs) are derived, which are in vitro analogues of early trophoblasts. Here, we show that TSCs contain plastic subpopulations reflecting developmental states ranging from pre- to post-implantation trophoblasts. However, upon exposure to a specific combination of embryonic inductive signals, TSCs globally acquire properties of pre-implantation polar trophoblasts (gene expression, self-renewal) juxtaposing the inner embryonic cells, and an enhanced, homogeneous epithelial phenotype. These lines of polar-like TSCs (pTSCs) represent a transcriptionally earlier state that more efficiently forms blastoids, whose inner embryonic cells then induce the patterning of gene expression along the embryonic-abembryonic axis. Altogether, delineating the requirements and properties of polar trophoblasts and blastocyst axis formation in vitro provides a foundation for the precise description and dissection of early development.

developmental biology↗

bioRxiv2018

Long-term expanding human airway organoids for disease modelling.

Organoids are self-organizing 3D structures grown from stem cells that recapitulate essential aspects of organ structure and function. Here we describe a method to establish long-term-expanding human airway organoids from broncho-alveolar biopsies or lavage material. The pseudostratified airway organoid epithelium consists of basal cells, functional multi-ciliated cells, mucus-producing goblet cells, and CC10-secreting club cells. Airway organoids derived from cystic fibrosis (CF) patients allow assessment of CFTR function in an organoid swelling assay. Organoid culture conditions also allow gene editing as well as the derivation of various types of lung cancer organoids. Respiratory syncytial virus (RSV) infection recapitulated central disease features and dramatically increases organoid cell motility, found to be driven by the non-structural viral NS2 protein. We conclude that human airway organoids represent versatile models for the in vitro study of hereditary, malignant, and infectious pulmonary disease.

cell biology↗