
The aim of this study was to develop an improvised protocol for ex vivo expansion of caprine satellite cells (SCs) using growth factors and their cryopreservation. The SCs were isolated from muscle tissue using collagenase type-I for enzymatic digestion. In vitro culture of SCs was done using Dulbecco's modified Eagle medium (DMEM) supplemented with 20% fetal bovine serum (FBS) and 15% horse serum. Immunofluorescence and PCR confirmed positive expression of PAX7 and MyoD, and negative expression of MyHC. Supplementation with 10 ng/ml basic fibroblast growth factor (bFGF) + 100 ng/ml insulin-like growth factor-1 (IGF-1) in the basal culture medium (DMEM + 2% FBS) showed similar results as control (routine culture medium). Subsequently, SCs were successfully cryopreserved using 10% dimethyl sulfoxide and 40% FBS with post-thaw viability of 74.72%. We have successfully established a protocol for the isolation, culture, and cryopreservation of goat SCs. Caprine SCs can be successfully expanded in vitro using growth factors (10 ng/ml bFGF and 100 ng/ml IGF-1) with minimum supplemental FBS in basal culture medium. Additionally, investigations could assess the viability and integrity of cryopreserved goat SCs post-thaw, ensuring that their proliferative capabilities remain intact. © 2025 Wiley Periodicals LLC. Basic Protocol: Isolation, culture, cost-effective expansion, and cryopreservation of caprine satellite cells.
Human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) have become a powerful source for the in vitro modeling of cardiac diseases and various other essential applications, including cardiotoxicity screening and regenerative cell replacement therapies. Although many differentiation protocols have been developed to generate cardiomyocytes from human pluripotent stem cells, these protocols are costly and complex, requiring expensive and often unnecessary components (e.g., B27 medium supplement). In addition, the use of animal-derived growth factors limits their use for regenerative medicine purposes. To address these issues, herein, we have developed an efficient, cost-effective, and protein-free hPSC-CM protocol using only two components: DMEM/F12 basal medium and l-ascorbic acid 2-phosphate. By eliminating xenobiotic and complex components, the efficiency of directed differentiations is increased, the variability between cardiac differentiations is decreased, and the scalability of cell production is enhanced. Adaptation of this efficient, low-cost, and user-friendly cardiac differentiation protocol will enrich the utility and applicability of hPSC-CMs in drug discovery, cell therapies, tissue engineering, disease modeling, precision medicine, and cardiac regenerative medicine. © 2025 Wiley Periodicals LLC. Basic Protocol 1: hPSC cell culture Basic Protocol 2: hPSC-CM differentiation Basic Protocol 3: Characterization of hPSC-CMs by immunofluorescence (IF) imaging.
Human induced pluripotent stem cell (hiPSC)-based disease modeling can be successfully recapitulated to mimic disease characteristics across various human pathologies. Glaucoma, a progressive optic neuropathy, primarily affects the retinal ganglion cells (RGCs). While multiple groups have successfully generated RGCs from non-diseased hiPSCs, producing RGCs from glaucomatous human samples holds significant promise for understanding disease pathology by revealing patient-specific disease signatures. Given that keratocytes originate from the neural crest and previous reports suggest that ocular fibroblasts from glaucomatous donors carry pathogenic signatures, it is highly plausible that these signatures imprinted within the keratocytes will also be present in the derived RGCs. Thus, we aimed to generate RGCs from both glaucomatous and non-glaucomatous donor keratocytes and validate disease-specific signatures in 3D retinal organoids and in isolated RGCs. Our protocol describes the generation of iPSCs from keratocytes of both glaucomatous and non-glaucomatous donors, followed by their differentiation into retinal organoids. Subsequent isolation and culturing of RGCs were performed. Disease signatures in the RGCs were validated in both 3D retinal organoids (ROs) and 2D RGC cultures, and glaucomatous RGCs in 3D and 2D cultures demonstrated increased cleaved CASP3 and significant RGC loss, indicating disease imprints in the hiPSC-derived RGCs. This model offers a venue and high throughput platform for studying glaucomatous disease pathology and holds significant potential for drug discovery using RGCs derived from human donors. © 2025 The Author(s). Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Culturing of keratocytes from human cadaveric donors Basic Protocol 2: Reprogramming donor keratocytes into iPSCs Basic Protocol 3: Evaluation of chromosomal loss during reprogramming in iPSCs by karyotyping Basic Protocol 4: Generation of 3D ROs Basic Protocol 5: Dissociation and culturing of RGCs from 3D ROs Support Protocol 1: Immunostaining for phenotypic characterization of cells Support Protocol 2: Sectioning of 3D ROs and immunostaining Support Protocol 3: Western blotting for cleaved CASP3 and THY1.
Bone marrow adipose tissue (BMAT) has garnered significant attention due to its critical roles in leukemia pathogenesis, cancer metastasis, and bone marrow failure. BMAT is a metabolically active, distinct tissue that differs from other fat depots. Marrow adipocytes, closely interacting with hematopoietic stem/progenitor cells and osteoblasts, play a pivotal role in regulating their functions. However, standardized methods for isolating and defining human BMAT (hBMAT) remain unclear. In animal models, BMAT is commonly isolated directly from the bone marrow through flushing, enzymatic digestion, or mechanical disruption. In humans, BMAT isolation often involves the adipogenic induction of bone marrow mesenchymal stem/stromal cells (BM-MSCs) derived from bone marrow aspirates. However, this approach reflects cellular responses to chemical stimuli and may not accurately represent in vivo differentiation potential. Similarly, BMAT obtained from hip or knee replacement surgeries might not reflect basal physiological conditions due to inflammatory influences. Here, we describe a direct method for culturing BMAT from the fatty layer of bone marrow aspirates obtained from healthy transplant donors. This protocol employs centrifugation and washing steps using basic laboratory equipment, offering simple and non-enzymatic approach. For validation, isolated cells are characterized according to the International Society for Cell & Gene Therapy (ISCT) criteria. © 2025 Wiley Periodicals LLC. Basic Protocol 1: Isolation of human BMAT-MSCs from the fatty layer of the bone marrow Basic Protocol 2: Culture expansion, trypsinization, and cryopreservation of BMAT-MSCs Support Protocol 1: Immunophenoypic characterization of human BMAT-MSCs by flow cytometry Support Protocol 2: In vitro characterization of multilineage differentiation potential of human BMAT-MSCs Support Protocol 3: Further characterization of gene expression in human BMAT-MSCs using qRT-PCR.
Astrocytes are key regulators of central nervous system (CNS) homeostasis, and their dysfunction is implicated in neurological and neurodegenerative disorders. Here, we describe a two-step protocol to generate astrocytes from human induced pluripotent stem cells (hiPSCs) using a bankable neural progenitor cell (NPC) intermediate, followed by low-density passaging and overexpression of the gliogenic transcription factor NFIA. A bankable NPC intermediate allows for facile differentiation into both purified neuronal and astrocyte cell types in parallel from the same genetic background, depending on the experimental needs. This article presents a protocol to generate NPCs from hiPSCs, which are then differentiated into hiPSC-derived astrocytes, termed iAstrocytes. The resulting iAstrocytes express key markers of astrocyte identity at transcript and protein levels by bulk RNA-Seq and immunocytochemistry, respectively. Additionally, they respond to the inflammatory stimuli poly(I:C) and generate waves of calcium activity in response to either physical activity or the addition of ATP. Our approach offers a simple and robust method to generate and characterize human astrocytes, which can be used to model human disease affecting this cell type. © 2024 Wiley Periodicals LLC. Basic Protocol 1: Differentiation of hiPSCs to NPCs Basic Protocol 2: Differentiation of NPCs into iAstrocytes Support Protocol 1: Molecular validation of iAstrocytes Support Protocol 2: Calcium imaging-based validation of iAstrocyte function Support Protocol 3: Differentiation of NPCs into neurons.
Human induced pluripotent stem cells (h-iPSCs) represent a potentially unlimited source for the generation of human hepatocyte-like cells (h-iHLCs) for the establishment of platforms to study drug-induced hepatotoxicity, liver disease modeling, and ultimately the application of h-iHLCs in treatment of patients with end-stage liver disease. To understand the impact of donor-specific factors on the generation of h-iHLCs, the model for the direct comparison of h-iHLCs and primary human hepatocytes (PHHs) from the same human donor is needed. This study proposes a step-by-step protocol for plating, expansion, and characterization of primary human hepatic non-parenchymal cells (h-NPCs) isolated from the human liver, the reprogramming of generated h-NPCs into h-iPSCs and subsequent differentiation of reprogrammed h-iPSCs into h-iHLCs. The ultimate goal is to compare the gene expression involved in hepatocyte metabolism between h-iHLCs and PHHs from the same human donor thus eliminating interdonor variability. This newly developed protocol of h-NPC culture, expansion, and reprogramming into h-iPSCs allows: (1) utilization of a single organ source (i.e., liver) for isolation of PHHs and h-NPCs and (2) the in-depth study of donor factors involved in the generation of h-iHLCs with direct comparison to PHHs from the same donor. © 2020 Wiley Periodicals LLC. Basic Protocol 1 : Plating and expansion of human hepatic NPCs in culture Basic Protocol 2 : Reprogramming of h-NPCs to h-NPC-derived induced pluripotent stem cells (h-iPSCs) Basic Protocol 3 : Culture, passaging, and freezing of h-iPSCs Support Protocol 1 : Confirmation of h-NPC ability to uptake Sendai virus: GFP-Sendai infection Support Protocol 2 : Characterization of h-NPCs amenable to transduction with Sendai particles Support Protocol 3 : Characterization of h-iPSCs: Clearance of viral reprogramming vectors Support Protocol 4 : Preparation of Matrigel-coated plates
The discovery of induced pluripotent stem cells (iPSCs) revolutionized the approach to cell therapy in regenerative medicine. Reprogramming of somatic cells into an embryonic-like pluripotent state provides an invaluable resource of patient-specific cells of any lineage. Implementation of procedures and protocols adapted to current good manufacturing practice (cGMP) requirements is critical to ensure robust and consistent high-quality iPSC manufacturing. The technology developed at Allele Biotechnology for iPSC generation under cGMP conditions is a powerful platform for derivation of pluripotent stem cells through a footprint-free, feeder-free, and xeno-free reprogramming method. The cGMP process established by Allele Biotechnology entails fully cGMP compliant iPSC lines where the entire manufacturing process, from tissue collection, cell reprogramming, cell expansion, cell banking and quality control testing are adopted. Previously, we described in this series of publications how to create iPSCs using mRNA only, and how to do so under cGMP conditions. In this article, we describe in detail how to culture, examine and storage cGMP-iPSCs using reagents, materials and equipment compliant with cGMP standards. © 2020 The Authors. Basic Protocol 1: iPSC Dissociation Support Protocol 1: Stem cell media Support Protocol 2: ROCK inhibitor preparation Support Protocol 3: Vitronectin coating Basic Protocol 2: iPSC Cryopreservation Basic Protocol 3: iPSC Thawing.
Genome editing has become one of the most powerful tools in present-day stem cell and regenerative medicine research, but despite its rapid acceptance and widespread use, some elements of the technology still need improvement. In this unit, we present data regarding the use of a new, more efficient type of transcription activator-like effector nuclease (TALEN) for gene editing. Our group has generated bicistronic genes in which classical TALEN coding sequences are linked by 2A elements to different reporter molecules, such as fluorochromes (TALEN-F) or membrane receptors (TALEN-M). This structure results in two proteins transcribed from the same transcript, of which the second (the reporter) can be used as the target for selection by fluorescence-assisted cell sorting (FACS) or magnetic-activated cell sorting (MACS). The application of these new TALEN genes allows a rapid enrichment of cells in which both members of the TALEN pair are active, thus eliminating the need for lengthy selection in culture and laborious characterization of a large number of clones. © 2020 by John Wiley & Sons, Inc. Basic Protocol 1: Generation of new TALENs Basic Protocol 2: Genome editing using TALEN-F Alternate Protocol 1: Generation of TALEN-M Support Protocol 1: mRNA in vitro transcription (IVT) of TALEN-T2A-reporter expression vector Alternate Protocol 2: Editing of primary T cells using TALEN-M Basic Protocol 3: Verifying gene editing Support Protocol 2: Rapid expansion protocol for edited T-cells.
Keratinocytes, as a primary somatic cell source, offer exceptional advantages compared to fibroblasts, which are commonly used for reprogramming. Keratinocytes can beat fibroblasts in reprogramming efficiency and reprogramming time and, in addition, can be easily and non-invasively harvested from human hair roots. However, there is still much to know about acquiring keratinocytes and maintaining them in cell culture. In this article, we want to offer readers the profound knowledge that we have gained since our initial use of keratinocytes for reprogramming more than 10 years ago. Here, all hints and tricks, from plucking the hair roots to growing and maintaining keratinocytes, are described in detail. Additionally, an overview of the currently used reprogramming methods, viral and non-viral, is included, with a special focus on their applicability to keratinocytes. This overview is intended to provide a brief but comprehensive insight into the field of keratinocytes and their use for reprogramming into induced pluripotent stem cells (iPSCs). © 2020 The Authors.
Translating basic biological knowledge into applications remains a key issue for effectively tackling neurodegenerative, neuroinflammatory, or neuroendocrine disorders. Efficient delivery of therapeutics across the neuroprotective blood-brain barrier (BBB) still poses a demanding challenge for drug development targeting central nervous system diseases. Validated in vitro models of the BBB could facilitate effective testing of drug candidates targeting the brain early in the drug discovery process during lead generation. We here review the potential of mono- or (isogenic) co-culture BBB models based on brain capillary endothelial cells (BCECs) derived from human-induced pluripotent stem cells (hiPSCs), and compare them to several available BBB in vitro models from primary human or non-human cells and to rodent in vivo models, as well as to classical and widely used barrier models [Caco-2, parallel artificial membrane permeability assay (PAMPA)]. In particular, we are discussing the features and predictivity of these models and how hiPSC-derived BBB models could impact future discovery and development of novel CNS-targeting therapeutics. © 2020 The Authors.
Structures resembling whole organs, called organoids, are generated using pluripotent stem cells and 3D culturing methods. This relies on the ability of cells to self-reorganize after dissociation. In combination with certain supplemented factors, differentiation can be directed toward the formation of several organ-like structures. Here, a protocol for the generation of retinal organoids containing all seven retinal cell types is described. This protocol does not depend on Matrigel, and by keeping the organoids single and independent at all times, fusion is prevented and monitoring of differentiation is improved. Comprehensive phenotypic characterization of the in vitro-generated retinal organoids is achieved by the protocol for immunostaining outlined here. By comparing different stages of retinal organoids, the decrease and increase of certain cell populations can be determined. In order to be able to detect even small differences, it is necessary to quantify the immunofluorescent signals, for which we have provided a detailed protocol describing signal quantitation using the image-processing program Fiji. © 2020 The Authors. Basic Protocol 1: Differentiation protocol for 3D retinal organoids Basic Protocol 2: Immunostaining protocol for cryosections of retinal organoids Support Protocol: Embedding and sectioning protocol for 3D retinal organoids Basic Protocol 3: Quantitation protocol using Fiji.
AbstractWe describe a protocol for efficient generation of human‐induced pluripotent stem cells (hiPSCs) from urine‐derived cells (UDCs) obtained from adult donors using self‐replicative RNA containing the reprogramming factors OCT3/4, SOX2, KLF4, GLIS1, and c‐MYC (ReproRNA‐OKSGM). After electroporation, transfection efficiency is quantified by measuring OCT3/4‐expressing UDCs using flow cytometry and should be ≥0.1%. hiPSC colonies emerge within 3 weeks after transfection and express multiple pluripotency markers. Moreover, the UDC‐derived hiPSCs are able to differentiate into cells of all three germ layers and display normal karyotypes. ReproRNA‐OKSGM is available commercially and only requires a single transfection step so that the protocol is readily accessible, as well as straightforward. In addition to a detailed step‐by‐step description for generating clonal hiPSCs from UDCs using ReproRNA‐OKSGM, we provide guidance for basic pluripotency characterization of the hiPSC lines. © 2020 The Authors.Basic Protocol: Reprogramming of urine‐derived cells using ReproRNA‐OKSGMSupport Protocol 1: Determination of the pluripotency status of hiPSCs by flow cytometrySupport Protocol 2: Characterization of functional pluripotency of hiPSCs
Advances in human pluripotent stem cell (hPSC) techniques have led them to become a widely used and powerful tool for a vast array of applications, including disease modeling, developmental studies, drug discovery and testing, and emerging cell-based therapies. hPSC workflows that require clonal expansion from single cells, such as CRISPR/Cas9-mediated genome editing, face major challenges in terms of efficiency, cost, and precision. Classical sub-cloning approaches depend on limiting dilution and manual colony picking, which are both time-consuming and labor-intensive, and lack a real proof of clonality. Here we describe the application of three different automated cell isolation and dispensing devices that can enhance the single-cell cloning process for hPSCs. In combination with optimized cell culture conditions, these devices offer an attractive alternative compared to manual methods. We explore various aspects of each device system and define protocols for their practical application. Following the workflow described here, single cell-derived hPSC sub-clones from each system maintain pluripotency and genetic stability. Furthermore, the workflows can be applied to uncover karyotypic mosaicism prevalent in bulk hPSC cultures. Our robust automated workflow facilitates high-throughput hPSC clonal selection and expansion, urgently needed in the operational pipelines of hPSC applications. © 2020 The Authors. Basic Protocol: Efficient automated hPSC single cell seeding and clonal expansion using the iotaSciences IsoCell platform Alternate Protocol 1: hPSC single cell seeding and clonal expansion using the Cellenion CellenONE single-cell dispenser Alternate Protocol 2: hPSC single cell seeding and clonal expansion using the Cytena single-cell dispenser Support Protocol 1: Coating cell culture plates with Geltrex Support Protocol 2: hPSC maintenance in defined feeder-free conditions Support Protocol 3: hPSC passaging in clumps Support Protocol 4: Laminin 521 coating of IsoCell plates and 96-well/384-well plates Support Protocol 5: Preparation of medium containing anti-apoptotic small molecules Support Protocol 6: 96- and 384-well target plate preparation prior to single cell seeding Support Protocol 7: Single cell dissociation of hPSCs Support Protocol 8: IsoCell-, CellenONE-, and Cytena-derived hPSC clone subculture and expansion.
Mesenchymal stem/stromal cells (MSCs) provide therapeutic effects in many diseases. Contrary to initial hypotheses, they act in a paracrine rather than a cellular manner. To this end, extracellular vesicles (EVs) have been found to mediate the therapeutic effects, even when harvested from MSC-conditioned cell culture supernatants. Lacking self-replicating activity and being so small that MSC-EV preparations can be sterilized by filtration, EVs provide several advantages as therapeutic agents over cellular therapeutics. At present, methods allowing EV preparation from larger volumes are scarce and regularly require special equipment. We have developed a polyethylene glycol-based precipitation protocol allowing extraction of EVs from several liters of conditioned medium. MSC-EVs prepared with this method have been successfully applied to a human graft-versus-host disease patient and to several animal models. Although the method comes with its own limitations, it is extremely helpful for the initial evaluation of EV-based therapeutic approaches. Here, we introduce the technique in detail and discuss all critical steps. © 2020 The Authors. Basic Protocol 1: Preparation of MSC-conditioned medium for scaled MSC-EV production Basic Protocol 2: PEG precipitation OF MSC-EV from MSC-conditioned medium.
The reproducibility of stem cell research relies on the constant availability of quality-controlled cells. As the quality of human induced pluripotent stem cells (hiPSCs) can deteriorate in the course of a few passages, cell banking is key to achieve consistent results and low batch-to-batch variation. Here, we provide a cost-efficient route to generate master and working cell banks for basic research projects. In addition, we describe minimal protocols for quality assurance including tests for sterility, viability, pluripotency, and genetic integrity. © 2020 The Authors. Basic Protocol 1: Expansion of hiPSCs Basic Protocol 2: Cell banking of hiPSCs Support Protocol 1: Pluripotency assessment by flow cytometry Support Protocol 2: Thawing control: Viability and sterility Support Protocol 3: Potency, viral clearance, and pluripotency: Spontaneous differentiation and qRT-PCR Support Protocol 4: Identity: Short tandem repeat analysis.
Great progress has been made with protocols for the differentiation and functional application of hPSC-cardiomyocytes (hPSC-CMs) in recent years; however, the cryopreservation and recovery of hPSC-CMs still presents challenges and few reports describe in detail the protocols and general workflow. In order to facilitate cryopreservation and recovery of hPSC-CMs for a wide range of applications, we provide detailed information and step-by-step protocols. The protocols are simple and use common reagents. They are comprised of a fast dissociation, cryopreservation using standard equipment, and gentle recovery following thawing. We discuss various features of the protocols, as well as their utilization in the context of common hPSC-CM differentiation and application workflows. Finally, we compare two proprietary and two common in-house formulations of cryopreservation media used for hPSC-CMs, and despite differences in their price and composition find broadly similar recovery rates and cellular function after thawing. © 2019 The Authors. Basic Protocol 1: Dissociation and cryopreservation of hPSC-CMs Basic Protocol 2: Thawing and recovery of cryogenically frozen hPSC-CMs.
Current Protocols in Stem Cell Biology is publishing a special collection of eight articles from members of the PluriCore Network in the German Stem Cell Network. © 2020 Wiley Periodicals LLC.
CRISPR-Cas9-based technologies have revolutionized experimental manipulation of mammalian genomes. However, limitations regarding the delivery and efficacy of these technologies restrict their application in primary cells. This article describes a protocol for penetrant, reproducible, and fast CRISPR-Cas9 genome editing in cell cultures derived from primary cells. The protocol employs transient nucleofection of ribonucleoprotein complexes composed of chemically synthesized 2'-O-methyl-3'phosphorothioate-modified single guide RNAs (sgRNAs) and purified Cas9 protein. It can be used both for targeted insertion-deletion mutation (indel) formation at up to >90% efficiency (via use of a single sgRNA) and for targeted deletion of genomic regions (via combined use of multiple sgRNAs). This article provides examples of the nucleofection buffer and programs that are optimal for patient-derived glioblastoma (GBM) stem-like cells (GSCs) and human neural stem/progenitor cells (NSCs), but the protocol can be readily applied to other primary cell cultures by modifying the nucleofection conditions. In summary, this is a relatively simple method that can be used for highly efficient and fast gene knockout, as well as for targeted genomic deletions, even in hyperdiploid cells such as many cancer stem-like cells. © 2020 Wiley Periodicals LLC Basic Protocol: Cas9:sgRNA ribonucleoprotein nucleofection for insertion-deletion (indel) mutation and genomic deletion generation in primary cell cultures.
Skin or hair loss (alopecia) may occur due to a wide variety of causes ranging from trauma to pathological processes including acquired or congenital causes. It would be ideal to replace them with immunologically compatible cells to avoid potentially exacerbating the condition. Deriving the replacement cells from human-induced pluripotent stem cells (hiPSCs) allows for sufficient scale up and using hiPSCs as the choice of human pluripotent stem cells (hPSC) will ensure immunocompatibility. Here we offer a protocol for differentiating hiPSCs into keratinocyte progenitor cells (KPC) and keratinocytes employing all-trans retinoic acid (ATRA) and L-ascorbic acid, (L-AA), bone morphogenic protein-4 (BMP4), and epidermal growth factor (EGF). We observed that the hiPSC-derived KPCs express the same panel of markers as primary hair follicle bulge stem cells (HFBSCs), including CD200, integrin α-6 (ITGA6), integrin β-1 (ITGB1), the transcription factor P63, keratin 15 (KRT15), and keratin 19 (KRT19). If permitted to differentiate further, the hiPSC-derived KPC lose CD200 expression and rather come to express keratin 14 (KRT14) indicating emergence of more mature terminally-differentiated keratinocytes. The HFBSCs are transplantable for hair follicle (HF) restoration, and the keratinocytes may be transplantable for therapy for large burns or ulcers. © 2020 Wiley Periodicals LLC. Basic Protocol 1: Reprogramming of normal human skin fibroblasts into normal hiPSCs using episomal DNA cocktail Basic Protocol 2: Differentiation of hiPSCs into KPCs and keratinocytes Alternate Protocol 2: EBS formation protocol using AggreWell™ plates (Antonchuk, 2013) Support Protocol 1: Passage hiPSC-KPC Support Protocol 2: Immunocytochemistry (ICC) Support Protocol 3: Immunofluorescence staining of cells for flow cytometry (FC).
The normal development of the pulmonary system is critical to transitioning from placental-dependent fetal life to alveolar-dependent newborn life. Human lung development and disease have been difficult to study due to the lack of an in vitro model system containing cells from the large airways and distal alveolus. This article describes a system that allows human embryonic stem cells (hESCs) and induced pluripotent stem cells (hiPSCs) to differentiate and form three-dimensional (3D) structures that emulate the development, cytoarchitecture, and function of the lung ("organoids"), containing epithelial and mesenchymal cell populations, and including the production of surfactant and presence of ciliated cells. The organoids can also be invested with mesoderm derivatives, differentiated from the same human pluripotent stem cells, such as alveolar macrophages and vasculature. Such lung organoids may be used to study the impact of environmental modifiers and perturbagens (toxins, microbial or viral pathogens, alterations in microbiome) or the efficacy and safety of drugs, biologics, and gene transfer. © 2020 Wiley Periodicals LLC. Basic Protocol: hESC/hiPSC dissection, definitive endoderm formation, and lung progenitor cell induction.