Biology subjects

Bao, X.

Publications and source records attributed to Bao, X..

At least 55 records · Page 3Linked to original sources

bioRxiv2024

Hyperbaric Oxygen-Induced acute lung injury: A Mouse Model Study on Pathogenesis and Recovery Dynamics

Hyperbaric oxygen (HBO) therapy is extensively used to treat a number of ailments. Although oxygen is crucial for survival, too much oxygen can be harmful. Excessive oxygen inhalation in a short period of time can lead to injury, and the lung is one of the main target organs. Lung injury induced by hyperbaric oxygen is notably more severe than that caused by normobaric oxygen, yet systematic research on such injury and its regression is scarce. In this study, mice were exposed to 2 atmospheres absolute (ATA), [>=] 95% oxygen for 2, 4, 6, 8 hours. Changes in lung histopathology, inflammation and expression of chemokines, vascular endothelial permeability, 8-OHdG and apoptotic cells were detected before and after the exposure. These parameters were also measured immediately, 12 hours, and 24 hours following 6 hours of exposure to 2 ATA of [>=]95% oxygen. The study indicates that lung damage from HBO is histologically characterized by bronchiolar and alveolar dilation, atelectasis, inflammatory cell infiltration, and hemorrhage. At 2 ATA with over 95% oxygen for 4 hours, there is a significant increase in pulmonary vascular permeability, as evidenced by elevated Evans blue scores (p = 0.02). After 6 hours of HBO exposure, there is a significant rise in pulmonary tissue pathology scores, 8-OHdG levels, and inflammatory and chemotactic factors (such as IL-6, CCL2, CCL3, CXCL5, and CXCL10), along with intercellular adhesion molecule 1 (ICAM1), vascular cell adhesion molecule 1(VCAM1). Moreover, it was observed that these markers continued to progress even after leaving the hyperoxic environment, peaking at 12 hours and starting to recover after 24 hours, suggesting that the peak of inflammatory lung damage occurs within 12 hours post-exposure, with recovery beginning at 24 hours. However, the content of Evans Blue, reflecting vascular endothelial damage, and ICAM1, VCAM1 remain significantly elevated 24 hours after leaving the hyperoxic environment, indicating that the pulmonary vasculature endothelium is the most sensitive to damage and the slowest to recover in HBO-induced lung injury. These findings provide evidence for the prevention and treatment of acute lung injury complications caused by HBO. NEW & NOTEWORTHYThis study systematically observed the development and outcome changes of ALI induced by HBO. In lung injuries caused by high partial pressure of oxygen, the pulmonary vascular endothelial cells are the first to be damaged and the slowest to recover. A 6-hour exposure to 2 ATA, [>=]95% oxygen of hyperbaric oxygen primarily causes oxidative DNA damage and inflammatory responses without significant apoptosis. The lung injury progresses even after leaving the high-oxygen setting, with inflammation peaking at 12 hours post-exposure and beginning to subside after 24 hours.

physiology↗

bioRxiv2023

VHL loss enables immune checkpoint blockade therapy by boosting type I interferon response.

Despite a moderate mutation burden, clear cell renal cell carcinoma (ccRCC) responds well to immune checkpoint blockade (ICB) therapy. Here we report that loss-of-function mutations in the von Hippel-Lindau (VHL) gene, the most frequent in ccRCC, underlies its responsiveness to ICB therapy. We demonstrate that genetic knockout of the VHL gene enhanced the efficacy of anti-PD-1 therapy in multiple murine tumor models in a T cell-dependent manner. Mechanistically, we discovered that upregulation of HIF1 and HIF2 induced by VHL gene loss decreased mitochondrial outer membrane potential and caused the cytoplasmic leakage of mitochondrial DNA (mtDNA), which triggered cGAS-STING activation and induced type I interferons. Our study thus provided novel mechanistic insights into the role of VHL gene loss in potentiating ccRCC immunotherapy.

cancer biology↗

bioRxiv2023

MAGIK: A rapid and efficient method to create lineage-specific reporters in human pluripotent stem cells

Precise insertion of a fluorescent protein into a lineage-specific gene in human pluripotent stem cells (hPSCs) presents challenges due to the low knockin efficiency and difficulties in selecting the correctly targeted cells. Here we introduce the ModRNA-based Activation for Gene Insertion and Knockin (MAGIK) approach to enhance knockin efficacy in hPSCs. MAGIK operates in two steps: first, it employs a Cas9-2A-p53DD modRNA with a mini-donor plasmid (without a drug-selection cassette) to significantly enhance efficiency; second, a dCas9 activator modRNA and a dgRNA are used to temporarily activate the successfully targeted gene, allowing for live cell sorting without single cell cloning. Consequently, MAGIK eliminates the need for drug selection cassettes or labor-intensive single cell colony screening, expediting precise genetic integration. We have demonstrated that MAGIK can be utilized to insert fluorescent proteins into various genes, including SOX17, NKX6.1, NKX2.5 and PDX1, across multiple hPSC lines, showcasing its robustness. This innovative MAGIK approach streamlines the process and provides a promising solution for targeted genetic modifications in hPSCs.

bioengineering↗

bioRxiv2023

A proximity-dependent biotinylation map of cytosol-facing organelle outer membrane proteome in living Arabidopsis cells

The cytosol-facing outer membrane (OM) of organelles communicates with other cellular compartments to exchange proteins, metabolites and signaling molecules. Cellular surveillance systems also target OM-resident proteins to control organellar homeostasis and ensure cell survival under stress. Using traditional approaches to discover OM proteins and identify their dynamically interacting partners remains challenging. In this study, we developed an OM proximity labeling (OMPL) system using biotin ligase-mediated proximity biotinylation to map the proximity proteome of the OMs of mitochondria, chloroplasts, and peroxisomes in living Arabidopsis (Arabidopsis thaliana) cells. We demonstrate the power of this system with the discovery of cytosolic factors and OM receptor candidates involved in local protein translation and translocation, membrane contact sites, and organelle quality control. This system also performed admirably for the rapid isolation of intact mitochondria and peroxisomes. Our data support the notion that TOM20-3 is a candidate for both a mitochondrial and a chloroplast receptor, and that PEX11D is a candidate for a peroxisome receptor for the coupling of protein translation and import. OMPL-generated OM proximity proteomes are valuable sources of candidates for functional validation and suggest directions for further investigation of important questions in cell biology.

cell biology↗

bioRxiv2023

Bovine milk glycoproteins inhibit SARS-CoV-2 and influenza virus co-infection

The attachment of S1 subunit of spike (S) protein to angiotensin-converting enzyme 2 (ACE2) is the first and crucial step of SARS-CoV-2 infection. Although S protein and ACE2 are heavily glycosylated, the precise roles of glycans in their interactions are still unclear. Here, we profiled the glycopatterns of S1 subunit of SARS-CoV-2 and ACE2, and found that the galactosylated glycoforms were dominant in both S1 subunit and ACE2. Interestingly, S1 subunit exhibited the property of glycan-binding protein (GBP) and adhered to the ACE2 via binding to the galactosylated glycans on the ACE2. Our earlier findings demonstrated that the sialylated glycoproteins isolated from bovine milk potently inhibit and neutralize viral activity against influenza A virus (IAV). Importantly, we proved further that the galactosylated glycans on isolated glycoproteins bind to the glycan recognition domains of S1 subunit and competitively inhibit binding of S1 subunit to ACE2 and ultimately impede the entry of SARS-CoV-2 pseudovirus into host cells. We provided a potential protein drug that could be multiple simultaneous inhibitor for coronavirus and IAV co-infection.

microbiology↗

bioRxiv2022

Perturbation of mitochondrial Ca2+ homeostasis activates cross-compartmental proteostatic response in Arabidopsis

Mitochondrial Ca2+ (mtCa2+) homeostasis is essential to mitochondrial functions. However, how mtCa2+ homeostasis is achieved and the consequences of impaired mtCa2+ homeostasis in plants is poorly understood. Here, we demonstrate a critical role for mitochondrial Ca2+ uniporter (MCU) in the control of mtCa2+ uptake for mtCa2+ homeostasis in planta by characterizing MCU mutants and overexpressed plants. Impaired MCU-controlled mtCa2+ homeostasis (iMUCH) in gain-of-function and loss-of-function MCU plants causes the misregulation of mitochondrial gene expression that triggers mitonuclear protein imbalance. Transcriptome integrated with proteomics analysis reveal activation of multiple compartmental UPR gene expression and decrease of cytosolic translation with selective repression of ribosome and RNA modification protein synthesis upon iMUCH. Intriguingly, TOR signalling is not involved in cytosolic translational response to iMUCH, but the reduction of eIF phosphorylation is evident under iMUCH induced mitochondrial stress. Thus, our study unveils the essential functions of MCU proteins for mtCa2+ homeostasis, and the involvement of MCU-controlled mtCa2+ homeostasis in mitochondrial stress dependent regulation of protein synthesis for cellular proteostasis that is connected to plant growth and stress resistance.

plant biology↗

bioRxiv2022

Alternative mRNA polyadenylation bridges mitochondrion-to-nucleus communication in Arabidopsis

Mitochondria produce signals besides energy and metabolites that influence plant growth and fitness. However, how mitochondrial signals are relayed to other cellular compartments is largely unknown. By applying poly(A)-site RNA-sequencing (PAS-seq) to wildtype Arabidopsis seedlings and a mutant in the histone demethylase JMJ30 treated with the mitochondrial electron transfer chain inhibitor antimycin A (AA), we identified a previously undefined mitochondrion-to-nucleus communication pathway by which mitochondrial functional state regulates co-transcriptionally alternative polyadenylation (APA) of nuclear mRNA. We observed a global shortening of 3' untranslated regions (UTRs) as a molecular signature of AA-activated mitochondrial retrograde response (MRR), which contributed in part to translational regulation of auxin response and cell wall biogenesis. JMJ30 regulated AA-induced 3' UTR shortening, resulting in more transcripts with shortened 3' UTRs upon AA treatment in a JMJ30 gain-of-function mutant and overexpression lines. We also report on the JMJ30-interacting protein CPSF30, a cleavage and polyadenylation specificity factor that recruits JMJ30 to modulate H3K27me3 status at its target loci. Our study illustrates how epigenetic modification and APA coordinate mitochondrion-to-nucleus communication to allow cells to rapidly respond to changes in mitochondrial functional state and shape plant growth and fitness. One-sentence summaryEpigenetic modification and APA coordinate mitochondrion-to-nucleus communication to allow cells to rapidly respond to changes in mitochondrial functional state and shape plant growth and fitness.

molecular biology↗

bioRxiv2022

Experimental Parameters-Based Monte-Carlo Simulation of Single-Molecule Localization Microscopy of Nuclear Pore Complex to Evaluate Clustering Algorithms

Single-molecule localization microscopy (SMLM) enables the detailed visualization of nuclear pore complexes (NPC) in vitro with sub-20 nm resolution. However, it is challenging to translate the localized coordinates in SMLM images to NPC functions because different algorithms to cluster localizations as individual NPCs can be biased without ground truth for validation. We developed a Monte-Carlo simulation to generate synthetic SMLM images of NPC and used the simulated NPC images as the ground truth to evaluate the performance of six clustering algorithms. We identified HDBSCAN as the optimal clustering algorithm for NPC counting and sizing. Furthermore, we compared the clustering results between the experimental and synthetic data for NUP133, a subunit in the NPC, and found them to be in good agreement.

bioinformatics↗

bioRxiv2022

Talaromyces marneffei suppresses human macrophages inflammatory by producing the truncated protein NCOR2-013 via TUT1-regulated alternative splicing

Talaromyces marneffei (T. marneffei) immune-escaping is an important factor for high mortality of talaromycosis. It is currently known that T. marneffei performs these functions through a variety of strategies, however, the role of alternative splicing (AS) in this process is poorly understood. Here we depicted the AS landscape in the macrophage upon T. marneffei infection via high-throughput RNA sequencing. Moreover, we identified a truncated protein of NCOR2/SMRT, namedly NCOR2-013, was significantly upregulated upon T. marneffei infection. Mechanistic analysis indicates that NCOR2-013 forms a co-repression complex with TBL1XR1/TBLR1 and HDAC3, thereby inhibiting JunB-mediated transcriptional activation of pro-inflammatory cytokines via the inhibition of histone acetylation. Also, we identified TUT1 as the AS regulator that involved in facilitating T. marneffei immune evasion via regulation of NCOR2-013 production. Collectively, the findings indicate that T. marneffei escapes macrophages killing through the TUT1-mediated the alternative splicing of NCOR2-013, which providing a new insight into the molecular mechanisms of T. marneffei immune evasion, and a potential targets for talaromycosis therapy.

microbiology↗

bioRxiv2022

Robust genome editing via modRNA-based Cas9 or base editor in human pluripotent stem cells

CRISPR systems have revolutionized biomedical research because they offer an unprecedented opportunity to explore the application of genome editing in human pluripotent stem cells (hPSCs). Due to the inherent simplicity of CRISPR systems, requiring a Cas protein and its corresponding single guide RNA (sgRNA), they are more widely adopted and used for diverse biomedical research than their predecessors (zinc finger nucleases and TALENs). However, a bottleneck of applying CRISPR systems in hPSCs is how to deliver CRISPR effectors easily and efficiently into hPSCs. Herein, we developed modified mRNA (modRNA) based CRIPSR systems that utilized Cas9 or base editor (ABE8e) modRNA for genome editing of hPSCs via simple lipid-based transfection. We have achieved 71.09% {+/-} 9.13% and 68.53% {+/-} 3.81% gene knockout (KO) efficiency with Cas9 modRNA and ABE8e modRNA, respectively, which is significantly higher than plasmid-based systems. In summary, we demonstrate that our non-integrating modRNA based CRISPR methods hold great promise as the more efficient and accessible techniques for genome editing of hPSCs.

bioengineering↗

bioRxiv2022

Engineering chimeric antigen receptor neutrophils from human pluripotent stem cells for targeted cancer immunotherapy

Neutrophils, the most abundant white blood cells in the circulation, are closely related to cancer development and progression. Primary neutrophils from healthy donors present potent cytotoxicity against different human cancer cell lines through direct contact and via the generation of reactive oxygen species (ROS). However, due to their short half-life and resistance to genetic modification, neutrophils have not yet been engineered with widely used chimeric antigen receptors (CARs) to enhance their anti-tumor cytotoxicity for targeted immunotherapy. Here, we genetically engineered human pluripotent stem cells (hPSCs) with different synthetic CARs and successfully differentiated them into functional neutrophils by implementing a novel chemically-defined differentiation platform. Neutrophils expressing the chlorotoxin (CLTX)-T-CAR presented specific cytotoxicity against glioblastoma (GBM) cells both in monolayer and 3D cultures. In a GBM xenograft mouse model, systematically-administered CLTX-T-CAR neutrophils also displayed enhanced anti-tumor activity and prolonged animal survival compared with peripheral blood-neutrophils, hPSC-neutrophils and CLTX-NK-CAR natural killer (NK) cells. Collectively, we established a new platform for production of CAR-neutrophils, paving the way to myeloid cell-based therapeutic strategies that would complement and boost current cancer treatment approaches.

bioengineering↗

bioRxiv2021

Changes of small non-coding RNAs by severe acute respiratory syndrome coronavirus 2 infection

The ongoing pandemic of coronavirus disease 2019 (COVID-19), which results from the rapid spread of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a significant global public health threat, with molecular mechanisms underlying its pathogenesis largely unknown. Small non-coding RNAs (sncRNAs) are known to play important roles in almost all biological processes. In the context of viral infections, sncRNAs have been shown to regulate the host responses, viral replication, and host-virus interaction. Compared with other subfamilies of sncRNAs, including microRNAs (miRNAs) and Piwi-interacting RNAs (piRNAs), tRNA-derived RNA fragments (tRFs) are relatively new and emerge as a significant regulator of host-virus interactions. Using T4 PNK-RNA-seq, a modified next-generation sequencing (NGS), we recently found that nasopharyngeal swabs (NPS) samples from SARS-CoV-2 positive and negative subjects show a significant difference in sncRNA profiles. There are about 166 SARS-CoV-2-impacted sncRNAs. Among them, tRFs are the most significantly affected and almost all impacted tRFs are derived from the 5-end of tRNAs (tRF5). Using a modified qRT-PCR, which was recently developed to specifically quantify tRF5s by isolating the tRF signals from its corresponding parent tRNA signals, we validated that tRF5s derived from tRNA GluCTC (tRF5-GluCTC), LysCTT (tRF5-LysCTT), ValCAC (tRF5-ValCAC), CysGCA (tRF5-CysGCA) and GlnCTG (tRF5-GlnCTG) are enhanced in NPS samples of SARS-CoV2 patients and SARS-CoV2-infected airway epithelial cells. In addition to host-derived ncRNAs, we also identified several sncRNAs derived from the virus (svRNAs), among which a svRNA derived from CoV2 genomic site 346 to 382 (sv-CoV2-346) has the highest expression. The induction of both tRFs and sv-CoV2-346 has not been reported previously, as the lack of the 3-OH ends of these sncRNAs prevents them to be detected by routine NGS. In summary, our studies demonstrated the involvement of tRFs in COVID-19 and revealed new CoV2 svRNAs.

microbiology↗

bioRxiv2021

A modified porous silicon microparticle promotes mucosal delivery of SARS-CoV-2 antigen and induction of potent and durable systemic and mucosal T helper 1 skewed protective immunity

Development of optimal SARS-CoV-2 vaccines to induce potent, long-lasting immunity and provide cross-reactive protection against emerging variants remains a high priority. Here, we report that a modified porous silicon microparticle (mPSM)-adjuvanted SARS-CoV-2 receptor-binding domain (RBD) vaccine activated dendritic cells and generated more potent and durable SARS-CoV-2-specific systemic humoral and type 1 helper T (Th) cell-mediated immune responses than alum-formulated RBD following parenteral vaccination, and protected mice from SARS-CoV-2 and Beta variant infection. mPSM facilitated the uptake of SARS-CoV-2 RBD antigens by nasal and airway epithelial cells. Parenteral and intranasal prime and boost vaccinations with mPSM-RBD elicited potent systemic and lung resident memory T and B cells and SARS-CoV-2 specific IgA responses, and markedly diminished viral loads and inflammation in the lung following SARS-CoV-2 Delta variant infection. Our results suggest that mPSM can serve as potent adjuvant for SARS-CoV-2 subunit vaccine which is effective for systemic and mucosal vaccination.

immunology↗

bioRxiv2021

Distribution and vulnerability of transcriptional outputs across the genome in Myc-amplified medulloblastoma cells

Myc plays a central role in tumorigenesis by orchestrating the expression of genes essential to numerous cellular processes1-4. While it is well established that Myc functions by binding to its target genes to regulate their transcription5, the distribution of the transcriptional output across the human genome in Myc-amplified cancer cells, and the susceptibility of such transcriptional outputs to therapeutic interferences remain to be fully elucidated. Here, we analyze the distribution of transcriptional outputs in Myc-amplified medulloblastoma (MB) cells by profiling nascent total RNAs within a temporal context. This profiling reveals that a major portion of transcriptional action in these cells was directed at the genes fundamental to cellular infrastructure, including rRNAs and particularly those in the mitochondrial genome (mtDNA). Notably, even when Myc protein was depleted by as much as 80%, the impact on transcriptional outputs across the genome was limited, with notable reduction mostly only in genes involved in ribosomal biosynthesis, genes residing in mtDNA or encoding mitochondria-localized proteins, and those encoding histones. In contrast to the limited direct impact of Myc depletion, we found that the global transcriptional outputs were highly dependent on the activity of Inosine Monophosphate Dehydrogenases (IMPDHs), rate limiting enzymes for de novo guanine nucleotide synthesis and whose expression in tumor cells was positively correlated with Myc expression. Blockage of IMPDHs attenuated the global transcriptional outputs with a particularly strong inhibitory effect on infrastructure genes, which was accompanied by the abrogation of MB cells proliferation in vitro and in vivo. Together, our findings reveal a real time action of Myc as a transcriptional factor in tumor cells, provide new insight into the pathogenic mechanism underlying Myc-driven tumorigenesis, and support IMPDHs as a therapeutic vulnerability in cancer cells empowered by a high level of Myc oncoprotein.

cancer biology↗

bioRxiv2021

MLC Seq: De novo sequencing of full-length tRNA isoforms by mass ladder complementation

tRNAs can exist in distinct isoforms because of different chemical modifications, which confounds attempts to accurately sequence individual tRNA species using next generation sequencing approaches or to quantify different RNA modifications at specific sites on a tRNA strand. Herein, we develop a mass spectrometric (MS) ladder complementation sequencing (MLC-Seq), allowing for direct and simultaneous sequencing of full-length tRNA molecules, including those with low abundance. MLC-seq is achieved by improved instrumentation, and advanced algorithms that identify each tRNA species and related isoforms in an RNA mixture, and assemble full MS ladders from partial ladders with missing ladder components. Using MLC-Seq, we successfully obtained the sequence of tRNA-Phe from yeast and tRNA-Glu from mouse hepatocytes, and simultaneously revealed new tRNA isoforms derived from nucleotide modifications. Importantly, MLC-Seq pinpointed the location and stoichiometry changes of RNA modifications in tRNA-Glu upon the treatment of dealkylated enzyme AlkB, which confirmed its known enzymatic activity and suggested previously unidentified effects in RNA editing.

biochemistry↗

bioRxiv2021

Direct induction of hemogenic endothelial progenitors from hPSCs by defined factors revealed by single-cell transcriptome analysis

Transcription factors (TFs) play critical roles in stem cell maintenance and differentiation. Using single cell RNA sequencing, we investigated TFs expressed in hemogenic endothelial (HE) progenitors differentiated from human pluripotent stem cells (hPSCs) and identified upregulated expression of SOXF factors SOX7, SOX17, and SOX18 in the HE population. To test whether overexpression of these factors increases HE differentiation efficiency, we established inducible hPSC lines and found only SOX17 improved differentiation. Temporal expression analysis further revealed SOX17 was turned on immediately before VE-Cadherin, indicating SOX17 may be a causative factor for HE differentiation. Upon SOX17 knockdown via CRISPR-Cas13d, HE differentiation was significantly abrogated. Strikingly, we discovered SOX17 overexpression alone is sufficient to generate more than 50% CD34+VE-cadherin+CD73- cells that could be directed to hematopoietic progenitors, which emerged via an endothelial-to-hematopoietic transition and significantly upregulated definitive hematopoietic transcriptional programs. Functional assays showed that these progenitors can differentiate into blood cells from multiple lineages. Our analyses reveal an uncharacterized function of SOX17 in directing hPSCs differentiation towards HE cells. Significance StatementHemogenic endothelial (HE) cells have been generated from human pluripotent stem cells (hPSCs) to study blood development. However, their full transcriptomic characterization and key genes involving in directing HE differentiation is unclear. Utilizing single cell RNA-seq analysis, we find that SOX17 is solely expressed in HE cells and is also required for HE differentiation. Strikingly, we find that overexpression of SOX17 alone is sufficient to program hPSCs into CD34+VE-cadherin+CD73-HE cells, which could further differentiate into blood progenitors. Our research reveals that SOX17 is sufficient to direct hPSCs differentiation to HE cells. ClassificationPhysical Sciences/Engineering; Biological Sciences/Cell Biology.

bioengineering↗

bioRxiv2021

Acyl chain shortening induced by inhibition of acetyl-CoA carboxylase renders phosphatidylcholine redundant

Phosphatidylcholine (PC) is an abundant membrane lipid component in most eukaryotes including yeast. PC has been assigned a multitude of functions in addition to that of building block of the lipid bilayer. Here we show that PC is evolvable essential in yeast by isolating suppressor mutants devoid of PC that exhibit robust growth. The requirement for PC is suppressed by monosomy of chromosome XV, or by a point mutation in the ACC1 gene encoding acetyl-CoA carboxylase. Although these two genetic adaptations rewire lipid biosynthesis differently, both decrease Acc1 activity thereby reducing the average acyl chain length. Accordingly, soraphen A, a specific inhibitor of Acc1, rescues a yeast mutant with deficient PC synthesis. In the aneuploid suppressor, up-regulation of lipid synthesis is instrumental to accomplish feed-back inhibition of Acc1 by acyl-CoA produced by the fatty acid synthase (FAS). The results show that yeast regulates acyl chain length by fine-tuning the activities of Acc1 and FAS, and indicate that PC evolved by benefitting the maintenance of membrane fluidity.

biochemistry↗

bioRxiv2020

Th17-skewed inflammation due to genetic deficiency of a cadherin stress sensor

Desmoglein 1 (Dsg1) is a cadherin restricted to stratified tissues of terrestrial vertebrates, which serve as essential physical and immune barriers. Dsg1s importance in epidermal integrity is underscored by genetic, autoimmune and bacterial toxin-mediated disorders interfering with Dsg1 function. Dsg1 loss-of-function mutations in humans result not only in skin lesions, but also multiple allergies, and isolated patient keratinocytes exhibit increased pro-allergic cytokine expression. However, the mechanism by which genetic deficiency of Dsg1 causes chronic inflammation is unknown. To determine the systemic response to Dsg1 loss, we deleted the three tandem Dsg1 genes in mice using CRISPR/Cas9. Whole transcriptome analysis of E18.5 Dsg1-/- skin showed changes consistent with the observed aberrant differentiation and barrier impairment. Comparing epidermal transcriptomes from E18.5 Dsg1-deficient mice and humans with Dsg1 mutations revealed a shared psoriatic-like IL-17-skewed inflammatory signature and less so a pro-allergic IL-4/13 signature. Although the impaired intercellular adhesion observed in Dsg1-/- mice resembles that resulting from autoimmune anti-Dsg1 pemphigus foliaceus antibodies, transcriptomic analysis of pemphigus skin lesions lacks a prominent IL-17 signature. Thus, beyond impairing the physical barrier, chronic loss of Dsg1 function through gene mutation results in a psoriatic-like inflammatory signature before birth, possibly predisposing to skin inflammation.

immunology↗