Biology subjects

Medina-Cano, D.

Publications and source records attributed to Medina-Cano, D..

6 recordsLinked to original sources

bioRxiv2025

Modeling tissue-resident macrophage development from mouse pluripotent stem cells

Tissue-resident macrophages (TRMs) are innate immune cells that participate in tissue development, homeostasis, and immune surveillance. Extensive efforts have been made to recapitulate TRM development from pluripotent stem cells (PSCs) in vitro to study molecular and cellular mechanisms of TRM development and to create cellular models of disease. However, available PSC models of mouse TRM development exhibit low overall efficiencies of TRM generation, produce heterogeneous off-target populations, and rely upon undefined media components, thus limiting their reproducibility, scalability, and widespread application as an experimental platform for TRM biology. To address these important limitations, we developed an efficient and reproducible protocol to faithfully recapitulate the stepwise differentiation of mouse PSCs (epiblast stem cells) into unspecialized, proliferative TRMs through the pro-definitive hematopoietic program under defined conditions. These immature TRMs can stably integrate into developing mouse neural organoids in vitro and acquire features of microglia. In addition, PSC-derived immature TRMs can stably engraft into the lung niche in vivo and adopt alveolar macrophage characteristics. This new platform for modeling mouse TRM development represents a powerful experimental model system for studying TRM function and dysfunction in development and disease.

developmental biology↗

bioRxiv2024

A mouse organoid platform for modeling cerebral cortex development and cis-regulatory evolution in vitro

Natural selection has shaped the gene regulatory networks that orchestrate the development of the neocortex, leading to diverse neocortical structure and function across mammals, but the molecular and cellular mechanisms driving phenotypic changes have proven difficult to characterize. Here, we develop a reproducible protocol to generate neocortical organoids from mouse epiblast stem cells (EpiSCs) that gives rise to diverse cortical cell types, including distinct classes of excitatory neurons (pre-plate, deep-layer, and upper-layer) and glia (oligodendrocyte precursor cells, myelinating oligodendrocytes, astrocytes, ependymal cells). Cortical organoids develop with similar kinetics to the mouse cortex in vivo and begin to exhibit features of maturation in glia and neuronal cell types relatively rapidly compared to human brain organoids. Using this new protocol, we generated cortical organoids from F1 hybrid EpiSCs derived from crosses between standard laboratory mice (C57BL/6J) and four wild-derived mouse strains from distinct sub-species spanning [~]1M years of evolutionary divergence. This allowed us to comprehensively map cis-acting transcriptional regulatory variation across developing cortical cell types using scRNA-seq. We identify hundreds of genes that exhibit dynamic allelic imbalances during cortical neurogenesis, providing the first insight into the developmental mechanisms underpinning changes in cortical structure and function between mouse strains. These experimental methods and cellular resources represent a powerful new platform for investigating mechanisms of gene regulation in the developing cerebral cortex.

developmental biology↗

bioRxiv2024

A pluripotent stem cell platform for in vitro systems genetics studies of mouse development

The directed differentiation of pluripotent stem cells (PSCs) from panels of genetically diverse individuals is emerging as a powerful experimental system for characterizing the impact of natural genetic variation on developing cell types and tissues. Here, we establish new PSC lines and experimental approaches for modeling embryonic development in a genetically diverse, outbred mouse stock (Diversity Outbred mice). We show that a range of inbred and outbred PSC lines can be stably maintained in the primed pluripotent state (epiblast stem cells -- EpiSCs) and establish the contribution of genetic variation to phenotypic differences in gene regulation and directed differentiation. Using pooled in vitro fertilization, we generate and characterize a genetic reference panel of Diversity Outbred PSCs (n = 230). Finally, we demonstrate the feasibility of pooled culture of Diversity Outbred EpiSCs as "cell villages", which can facilitate the differentiation of large numbers of EpiSC lines for forward genetic screens. These data can complement and inform similar efforts within the stem cell biology and human genetics communities to model the impact of natural genetic variation on phenotypic variation and disease-risk.

developmental biology↗

bioRxiv2024

Transcriptional remodeling by OTX2 directs specification and patterning of mammalian definitive endoderm

O_LIMouse and human pluripotent cells with multipurpose degron alleles establish versatile platforms to dissect cell type-specific functions of the pleiotropic transcription factor OTX2 C_LIO_LIOTX2 controls molecular programs required for anterior-posterior patterning of the developing gut C_LIO_LIOTX2 establishes and maintains chromatin accessibility at distinct distal gene regulatory elements in definitive endoderm C_LIO_LIOTX2 functions as a patterning factor across different germ layers and species C_LI The molecular mechanisms that drive essential developmental patterning events in the mammalian embryo remain poorly understood. To generate a conceptual framework for gene regulatory processes during germ layer specification, we analyzed transcription factor (TF) expression kinetics around gastrulation and during in vitro differentiation. This approach identified Otx2 as a candidate regulator of definitive endoderm (DE), the precursor of all gut-derived tissues. Analysis of multipurpose degron alleles in gastruloid and directed differentiation models revealed that loss of OTX2 before or after DE specification alters the expression of core components and targets of specific cellular signaling pathways, perturbs adhesion and migration programs as well as de-represses regulators of other lineages, resulting in impaired foregut specification. Key targets of OTX2 are conserved in human DE. Mechanistically, OTX2 is required to establish chromatin accessibility at candidate enhancers, which regulate genes critical to establishing an anterior cell identity in the developing gut. Our results provide a working model for the progressive establishment of spatiotemporal cell identity by developmental TFs across germ layers and species, which may facilitate the generation of gut cell types for regenerative medicine applications.

developmental biology↗

bioRxiv2021

Rapid and robust directed differentiation of mouse epiblast stem cells into definitive endoderm and forebrain organoids

Directed differentiation of pluripotent stem cells (PSCs) is a powerful model system for deconstructing embryonic development. Although mice are the most advanced mammalian model system for genetic studies of embryonic development, state-of-the-art protocols for directed differentiation of mouse PSCs into defined lineages require additional steps and generate target cell types with lower purity than analogous protocols for human PSCs, limiting their application as models for mechanistic studies of development. Here, we examine the potential of mouse epiblast stem cells (EpiSCs) cultured in media containing Wnt pathway inhibitors as a starting point for directed differentiation. As a proof-of-concept, we focused our efforts on two specific cell/tissue types that have proven difficult to generate efficiently and reproducibly from mouse embryonic stem cells: definitive endoderm and neural organoids. We present new protocols for rapid generation of nearly pure definitive endoderm and forebrain-patterned neural organoids that model the development of prethalamic and hippocampal neurons. These differentiation models present new possibilities for combining mouse genetic tools with in vitro differentiation to characterize molecular and cellular mechanisms of embryonic development. SUMMARY STATEMENTNew optimized protocols for directed differentiation of mouse epiblast stem cells into definitive endoderm and forebrain-patterned organoids.

developmental biology↗

bioRxiv2020

MINPP1 prevents intracellular accumulation of the cation chelator inositol hexakisphosphate and is mutated in Pontocerebellar Hypoplasia

Inositol polyphosphates are vital metabolic and secondary messengers, involved in diverse cellular functions. Therefore, tight regulation of inositol polyphosphate metabolism is essential for proper cell physiology. Here, we describe an early-onset neurodegenerative syndrome caused by loss-of-function mutations in the multiple inositol polyphosphate phosphatase 1 gene (MINPP1). Patients were found to have a distinct type of Pontocerebellar Hypoplasia with typical basal ganglia involvement on neuroimaging. We found that patient-derived and genome edited MINPP1-/- induced pluripotent stem cells (iPSCs) are not able to differentiate efficiently into neurons. MINPP1 deficiency results in an intracellular imbalance of the inositol polyphosphate metabolism. This metabolic defect is characterized by an accumulation of highly phosphorylated inositols, mostly inositol hexakiphosphate (IP6), detected in HEK293, fibroblasts, iPSCs and differentiating neurons lacking MINPP1. In mutant cells, higher IP6 level is expected to be associated with an increased chelation of intracellular cations, such as iron or calcium, resulting in decreased levels of available ions. These data suggest the involvement of IP6-mediated chelation on Pontocerebellar Hypoplasia disease pathology and thereby highlight the critical role of MINPP1 in the regulation of human brain development and homeostasis.

genetics↗