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Introduction: Environmental exposures and experimental manipulations can alter the ontogenetic composition of tissue-resident macrophages. However, the impact of these alterations on subsequent immune responses, particularly in allergic airway diseases, remains poorly understood. This study aims to elucidate the significance of modified macrophage ontogeny resulting from environmental exposures on allergic airway responses to house dust mite (HDM) allergen. Methods: We utilized embryonic lineage labeling to delineate the ontogenetic profile of tissue-resident macrophages at baseline and following the resolution of repeated lipopolysaccharide (LPS)-induced lung injury. We investigated differences in house dust mite (HDM)-induced allergy to assess the influence of macrophage ontogeny on allergic airway responses. Additionally, we employed single-cell RNA sequencing (scRNAseq) and immunofluorescent staining to characterize the pulmonary macrophage composition, associated pathways, and tissue localization. Results: Our findings demonstrate that the ontogeny of homeostatic alveolar and interstitial macrophages is altered after the resolution from repeated LPS-induced lung injury, leading to the replacement of embryonic-derived by bone marrow-derived macrophages. This shift in macrophage ontogeny is associated with reduced HDM-induced allergic airway responses. Through scRNAseq and immunofluorescent staining, we identified a distinct subset of resident-derived interstitial macrophages expressing genes associated with allergic airway diseases, localized adjacent to terminal bronchi, and diminished by prior LPS exposure. Discussion: These results suggest a pivotal role for pulmonary macrophage ontogeny in modulating allergic airway responses. Moreover, our findings highlight the implications of prior environmental exposures in shaping future immune responses and influencing the development of allergies. By elucidating the mechanisms underlying these phenomena, this study provides valuable insights into potential therapeutic targets for allergic airway diseases and avenues for further research into immune modulation and allergic disease prevention.
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Macrófagos Alveolares , Transcriptoma , Animales , Ratones , Macrófagos Alveolares/inmunología , Macrófagos Alveolares/metabolismo , Pyroglyphidae/inmunología , Hipersensibilidad Respiratoria/inmunología , Pulmón/inmunología , Modelos Animales de Enfermedad , Ratones Endogámicos C57BL , Alérgenos/inmunología , Lipopolisacáridos , Femenino , Hipersensibilidad/inmunologíaRESUMEN
The pathogenic and cross-species transmission potential of SARS-CoV-2-related coronaviruses (CoVs) remain poorly characterized. Here we recovered a wild-type pangolin (Pg) CoV GD strain including derivatives encoding reporter genes using reverse genetics. In primary human cells, PgCoV replicated efficiently but with reduced fitness and showed less efficient transmission via airborne route compared with SARS-CoV-2 in hamsters. PgCoV was potently inhibited by US Food and Drug Administration approved drugs, and neutralized by COVID-19 patient sera and SARS-CoV-2 therapeutic antibodies in vitro. A pan-Sarbecovirus antibody and SARS-CoV-2 S2P recombinant protein vaccine protected BALB/c mice from PgCoV infection. In K18-hACE2 mice, PgCoV infection caused severe clinical disease, but mice were protected by a SARS-CoV-2 human antibody. Efficient PgCoV replication in primary human cells and hACE2 mice, coupled with a capacity for airborne spread, highlights an emergence potential. However, low competitive fitness, pre-immune humans and the benefit of COVID-19 countermeasures should impede its ability to spread globally in human populations.
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COVID-19 , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo , Cricetinae , Humanos , Animales , Ratones , Especificidad del Huésped , Pangolines , SARS-CoV-2/genética , COVID-19/prevención & control , Anticuerpos Antivirales , Vacunas contra la COVID-19 , Ratones Endogámicos BALB CRESUMEN
Using scRNA-seq and microscopy, we describe a cell that is enriched in the lower airways of the developing human lung and identified by the unique coexpression of SCGB3A2/SFTPB/CFTR. To functionally interrogate these cells, we apply a single-cell barcode-based lineage tracing method, called CellTagging, to track the fate of SCGB3A2/SFTPB/CFTR cells during airway organoid differentiation in vitro. Lineage tracing reveals that these cells have a distinct differentiation potential from basal cells, giving rise predominantly to pulmonary neuroendocrine cells and a subset of multiciliated cells distinguished by high C6 and low MUC16 expression. Lineage tracing results are supported by studies using organoids and isolated cells from the lower noncartilaginous airway. We conclude that SCGB3A2/SFTPB/CFTR cells are enriched in the lower airways of the developing human lung and contribute to the epithelial diversity and heterogeneity in this region.
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Regulador de Conductancia de Transmembrana de Fibrosis Quística , Pulmón , Humanos , Regulador de Conductancia de Transmembrana de Fibrosis Quística/metabolismo , Células Madre/metabolismo , Diferenciación Celular , Linaje de la Célula , Organoides , Células Epiteliales/metabolismoRESUMEN
The ontogenetic composition of tissue-resident macrophages following injury, environmental exposure, or experimental depletion can be altered upon re-establishment of homeostasis. However, the impact of altered resident macrophage ontogenetic milieu on subsequent immune responses is poorly understood. Hence, we assessed the effect of macrophage ontogeny alteration following return to homeostasis on subsequent allergic airway responses to house dust mites (HDM). Using lineage tracing, we confirmed alveolar and interstitial macrophage ontogeny and their replacement by bone marrow-derived macrophages following LPS exposure. This alteration in macrophage ontogenetic milieu reduced allergic airway responses to HDM challenge. In addition, we defined a distinct population of resident-derived interstitial macrophages expressing allergic airway disease genes, located adjacent to terminal bronchi, and reduced by prior LPS exposure. These findings support that the ontogenetic milieu of pulmonary macrophages is a central factor in allergic airway responses and has implications for how prior environmental exposures impact subsequent immune responses and the development of allergy.
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The mode of acquisition and causes for the variable clinical spectrum of coronavirus disease 2019 (COVID-19) remain unknown. We utilized a reverse genetics system to generate a GFP reporter virus to explore severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pathogenesis and a luciferase reporter virus to demonstrate sera collected from SARS and COVID-19 patients exhibited limited cross-CoV neutralization. High-sensitivity RNA in situ mapping revealed the highest angiotensin-converting enzyme 2 (ACE2) expression in the nose with decreasing expression throughout the lower respiratory tract, paralleled by a striking gradient of SARS-CoV-2 infection in proximal (high) versus distal (low) pulmonary epithelial cultures. COVID-19 autopsied lung studies identified focal disease and, congruent with culture data, SARS-CoV-2-infected ciliated and type 2 pneumocyte cells in airway and alveolar regions, respectively. These findings highlight the nasal susceptibility to SARS-CoV-2 with likely subsequent aspiration-mediated virus seeding to the lung in SARS-CoV-2 pathogenesis. These reagents provide a foundation for investigations into virus-host interactions in protective immunity, host susceptibility, and virus pathogenesis.
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Betacoronavirus/genética , Infecciones por Coronavirus/patología , Infecciones por Coronavirus/virología , Neumonía Viral/patología , Neumonía Viral/virología , Sistema Respiratorio/virología , Genética Inversa/métodos , Anciano , Enzima Convertidora de Angiotensina 2 , Animales , Anticuerpos Monoclonales/inmunología , Anticuerpos Neutralizantes/inmunología , Betacoronavirus/inmunología , Betacoronavirus/patogenicidad , COVID-19 , Línea Celular , Células Cultivadas , Chlorocebus aethiops , Infecciones por Coronavirus/inmunología , Infecciones por Coronavirus/terapia , Fibrosis Quística/patología , ADN Recombinante , Femenino , Furina/metabolismo , Humanos , Inmunización Pasiva , Pulmón/metabolismo , Pulmón/patología , Pulmón/virología , Masculino , Persona de Mediana Edad , Mucosa Nasal/metabolismo , Mucosa Nasal/patología , Mucosa Nasal/virología , Pandemias , Peptidil-Dipeptidasa A/metabolismo , Neumonía Viral/inmunología , Sistema Respiratorio/patología , SARS-CoV-2 , Serina Endopeptidasas/metabolismo , Células Vero , Virulencia , Replicación Viral , Sueroterapia para COVID-19RESUMEN
Improved tools have led to a burgeoning understanding of lung regeneration in mice, but it is not yet known how these insights may be relevant to acute lung injury in humans. We report in detail two cases of fulminant idiopathic acute lung injury requiring extracorporeal membrane oxygenation in previously healthy young adults with acute respiratory distress syndrome, one of whom required lung transplantation. Biopsy specimens showed diffuse alveolar injury with a striking paucity of alveolar epithelial regeneration, rare hyaline membranes, and diffuse contiguous airspace lining by macrophages. This novel constellation was termed diffuse alveolar injury with delayed epithelization. In addition, mirroring data from murine models of lung injury/regeneration, peribronchiolar basaloid pods (previously described as squamous metaplasia) and ciliated bronchiolarization were identified in these patients and in 39% of 57 historical cases with diffuse alveolar damage. These findings demonstrate a common and clinically relevant human disease correlate for murine models of severe acute lung injury. Evidence suggests that peribronchiolar basaloid pods and bronchiolarization are related spatially and temporally and likely represent overlapping sequential stages of the response to severe distal airway injury.
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Lesión Pulmonar Aguda/patología , Oxigenación por Membrana Extracorpórea , Trasplante de Pulmón , Fibrosis Pulmonar/patología , Regeneración/fisiología , Lesión Pulmonar Aguda/cirugía , Lesión Pulmonar Aguda/terapia , Adulto , Femenino , Humanos , Masculino , Resultado del TratamientoAsunto(s)
Lesión Pulmonar Aguda/patología , Alveolos Pulmonares/patología , Repitelización , Síndrome de Dificultad Respiratoria/patología , Lesión Pulmonar Aguda/etiología , Lesión Pulmonar Aguda/terapia , Adulto , Oxigenación por Membrana Extracorpórea/métodos , Femenino , Humanos , Trasplante de Pulmón , Masculino , Síndrome de Dificultad Respiratoria/complicaciones , Síndrome de Dificultad Respiratoria/terapia , TiempoRESUMEN
Loss-of-function mutations in SWI/SNF chromatin-remodeling subunit genes are observed in many cancers, but an oncogenic role for SWI/SNF is not well established. Here, we reveal that ACTL6A, encoding an SWI/SNF subunit linked to stem cell and progenitor cell function, is frequently co-amplified and highly expressed together with the p53 family member p63 in head and neck squamous cell carcinoma (HNSCC). ACTL6A and p63 physically interact, cooperatively controlling a transcriptional program that promotes proliferation and suppresses differentiation, in part through activation of the Hippo-YAP pathway via regulators including WWC1. Ectopic ACTL6A/p63 expression promotes tumorigenesis, while ACTL6A expression and YAP activation are highly correlated in primary HNSCC and predict poor patient survival. Thus, ACTL6A and p63 collaborate as oncogenic drivers in HNSCC.
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Actinas/fisiología , Proteínas Adaptadoras Transductoras de Señales/fisiología , Carcinoma de Células Escamosas/etiología , Proteínas Cromosómicas no Histona/fisiología , Proteínas de Unión al ADN/fisiología , Neoplasias de Cabeza y Cuello/etiología , Proteínas de la Membrana/fisiología , Fosfoproteínas/fisiología , Animales , Carcinoma de Células Escamosas/mortalidad , Línea Celular Tumoral , Proliferación Celular , Neoplasias de Cabeza y Cuello/mortalidad , Vía de Señalización Hippo , Humanos , Péptidos y Proteínas de Señalización Intracelular/fisiología , Ratones , Pronóstico , Proteínas Serina-Treonina Quinasas/fisiología , Carcinoma de Células Escamosas de Cabeza y Cuello , Factores de Transcripción , Transcriptoma , Proteínas Señalizadoras YAPRESUMEN
Cell-fate decisions and pluripotency are dependent on networks of key transcriptional regulators. Recent reports demonstrated additional functions of pluripotency-associated factors during early lineage commitment. The T-box transcription factor TBX3 has been implicated in regulating embryonic stem cell self-renewal and cardiogenesis. Here, we show that TBX3 is dynamically expressed during specification of the mesendoderm lineages in differentiating embryonic stem cells (ESCs) in vitro and in developing mouse and Xenopus embryos in vivo. Forced TBX3 expression in ESCs promotes mesendoderm specification by directly activating key lineage specification factors and indirectly by enhancing paracrine Nodal/Smad2 signaling. TBX3 loss-of-function analyses in the Xenopus underline its requirement for mesendoderm lineage commitment. Moreover, we uncovered a functional redundancy between TBX3 and Tbx2 during Xenopus gastrulation. Taken together, we define further facets of TBX3 actions and map TBX3 as an upstream regulator of the mesendoderm transcriptional program during gastrulation.
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Diferenciación Celular , Células Madre Embrionarias/citología , Gastrulación/genética , Mesodermo/crecimiento & desarrollo , Proteínas de Dominio T Box/biosíntesis , Animales , Linaje de la Célula , Regulación del Desarrollo de la Expresión Génica/genética , Mesodermo/metabolismo , Ratones , Proteína Nodal/biosíntesis , Proteína Nodal/genética , Proteína Smad2/genética , Proteínas de Dominio T Box/genética , XenopusRESUMEN
The miR-290 cluster is expressed in embryonic stem cells (ESCs) and is important for the maintenance of pluripotency, but little is known about the mechanisms regulating the early embryonic microRNA cluster (EEmiRC) expression. Here we report the identification of a 332-bp intragenic enhancer (IE) able to modulate the transcription of the mouse EEmiRC locus, presumably through binding of transcription modulators like Oct3/4, Sox2 and CTCF. This IE also contains a CpG island showing a differential pattern of DNA and histone methylation marks during differentiation of ESCs, which places EEmiRC in a novel regulatory feedback loop with DNA methylases. Deletion of IE significantly reduced the transcription of the EEmiRC, further proving the importance of this region in regulating the expression of EEmiRC.