Single-cell RNA sequencing depicts the local cell landscape in thyroid-associated ophthalmopathy

Single-cell multiomic analysis unveils the immune landscape dynamics of graves' ophthalmopathy

Graves' ophthalmopathy (GO) is an autoimmune disease that occurs concurrently with Graves' disease, potentially leading to facial disfigurement and irreversible vision loss. However, the molecular characteristics of cellular changes in the peripheral immune environment of GO patients remain unclear. This study presents a multi-omics single-cell analysis of peripheral blood from GO patients and healthy controls, revealing key molecular alterations in immune cell subpopulations. We identify increased chromatin accessibility and regulatory activity of pro-inflammatory factors, such as FOS and NF-κB family. Immune repertoire analysis shows enhanced diversity in GO patients. Notably, GO-specific clonal expansions are enriched in CD8 effector T (CD8 Te) cells, which exhibit signs of enhanced T cell chemotaxis and exhaustion. Multi-omics integration analysis reveals that changes in SLC35G1 and IDNK expression in CD8 Te are linked to disease phenotypes, with trends aligning with experimental results. We find that this cell cluster could infiltrate into orbital tissues and upregulate fibrosis-related pathways associated with fibroblasts in GO. These findings indicate its potential role in driving disease progression. Our study reveals the epigenetic and transcriptomic landscape in the peripheral blood of GO patients, enhancing the understanding of the pathogenic molecular mechanisms and offering potential directions for prevention and treatment.

Single-cell RNA sequencing highlights the role of proinflammatory fibroblasts, vascular endothelial cells, and immune cells in the keloid immune microenvironment

BACKGROUND

Keloids, characterized by an aberrant wound-healing process and a highly complex immune microenvironment, pose significant challenges for clinical management. Fibroblasts and vascular endothelial cells (VEC) were identified as the leading cells of keloid development. However, their roles in the keloid immune landscape have yet to be thoroughly elucidated.

METHODS

To explore the functional state of cells in the immune landscape of keloids, we conducted a single-cell RNA sequencing analysis on the tissue from three keloid lesions and two specimens of healthy skin. We simultaneously utilized available keloid data from the public database for external validation.

RESULTS

Specific subsets, such as proinflammatory fibroblasts (piF) and VEC, were markedly elevated in lesional skin compared to normal skin. Subsequent differential gene expression and Gene Ontology analyses indicated that these subsets may be involved in shaping the microenvironment. In keloids, there is an increased expression of immune-associated genes (P < 0.05), including TNFRSF6B, HGF, and TGFB3, alongside a decreased expression of inflammatory chemokines in the piF. Moreover, the significant upregulation of immune suppressive genes (P < 0.05), including CD39, CD73, and HIF1A, suggested the potential involvement of VEC as a conditional immune subpopulation in the keloid microenvironment. Immune cell communication analysis revealed preferential enrichment of macrophages and Tregs, highlighting intensified macrophage-centered interactions within the keloid microenvironment.

CONCLUSION

Our study highlighted the role of piF and VEC in the immune microenvironment of keloids for the first time, providing potential targets for therapeutic development.

The CD163 + tissue-infiltrating macrophages regulate ferroptosis in thyroid-associated ophthalmopathy orbital fibroblasts via the TGF-β/Smad2/3 signaling pathway

BACKGROUND

Thyroid-associated ophthalmopathy (TAO) is a thyroid function-related, organ-specific autoimmune disease that primarily leads to specific reactive changes and tissue remodeling in the periocular region. The exact pathogenesis of TAO remains unclear.

METHODS

High-throughput gene expression datasets related to TAO were comprehensively retrieved from the Gene Expression Omnibus (GEO) database, selecting GSE174139 and GSE158464 for analysis. Differentially expressed genes (DEGs) between TAO patients and healthy controls were identified, and ferroptosis-related genes (FRGs) were obtained from the FerrDb database. The intersection of DEGs and FRGs yielded ferroptosis-related genes associated with TAO.The transcriptional expression of FRGs was validated using real-time quantitative polymerase chain reaction (RT-qPCR) on orbital adipose tissue samples from TAO patients and healthy controls. Single-cell sequencing of six human tissue samples further analyzed changes in cellular subpopulations within the TAO microenvironment.Additionally, a co-culture model of CD163 + macrophages and TAO orbital fibroblasts, along with an in vitro TGF-β1-induced orbital fibroblast (OF) model, was constructed to validate the role of the TGF-β1/SMAD2/3 axis in ferroptosis regulation. Finally, potential clinical drugs targeting CD163 + macrophages with high ferroptosis activity in TAO were predicted using the Random Walk with Restart (RWR) algorithm combined with the DGIdb database.

RESULTS

We first utilized TAO-related datasets from the GEO database, combined with the FerrDb ferroptosis database, to identify changes in iron metabolism genes during TAO progression through differential expression analysis, screening 7 key ferroptosis-related proteins. In vitro validation revealed that all but AOPQ and LGMN, which were upregulated, exhibited downregulated expression.Single-cell sequencing of orbital connective tissue from 4 TAO patients and 2 healthy controls identified 16,364 cells spanning 18 cell types. Analysis of the 7 key ferroptosis-related proteins revealed that fibroblasts and macrophages displayed elevated ferroptosis signaling during TAO progression. Subcluster analysis of macrophages identified 4 distinct subpopulations, with the C2 subpopulation-characterized by high expression of CD163 and CCL18-exhibiting prominent ferroptosis activation signals.Further validation using clinical tissue samples, a co-culture model of CD163 + macrophages and TAO orbital fibroblasts, and an in vitro TGF-β1-induced orbital fibroblast (OF) model confirmed aberrant activation of the TGF-β1/SMAD2/3 pathway as a key regulator of ferroptosis. Hub gene analysis of C2 subpopulation marker genes, combined with the DGIdb database, predicted potential clinical drugs targeting the C2 macrophages.

CONCLUSION

This study, integrating single-cell RNA-Seq and bulk transcriptome analysis, revealed the involvement of CD163 + tissue-infiltrating macrophages in regulating ferroptosis of orbital fibroblasts during TAO progression and identified therapeutic candidates targeting macrophage ferroptosis signaling in TAO. Furthermore, in vitro experiments demonstrated that activation of the TGF-β1/SMAD2/3 axis promotes ferroptosis in TAO orbital fibroblasts, highlighting a novel pathway for potential therapeutic intervention.

Spatially resolved atlas of breast cancer uncovers intercellular machinery of venular niche governing lymphocyte extravasation

Breast cancers present intricate microenvironments comprising heterotypic cellular interactions, yet a comprehensive spatial map remained to be established. Here, we employed the DNA nanoball-based genome-wide in situ sequencing (Stereo-seq) to visualize the geospatial architecture of 30 primary breast tumors and metastatic lymph nodes across different molecular subtypes. This unprecedented high-resolution atlas unveils the fine structure of the tumor vasculature, highlighting heterogeneity in phenotype, spatial distribution, and intercellular communication within both endothelial and perivascular cells. In particular, venular smooth muscle cells are identified as the primary source of CCL21/CCL19 within the microenvironment. In collaboration with ACKR1-positive endothelial cells, they create a chemokine-rich venular niche to synergistically promote lymphocyte extravasation into tumors. High venule density predicts increased immune infiltration and improved clinical outcomes. This study provides a detailed spatial landscape of human breast cancer, offering key insights into the venular regulation of tumor immune infiltration.

Correlation between orbital immune cell subsets and clinical activity in thyroid eye disease

PURPOSE

To assess correlations between orbital immune cell subsets and the clinical activity in thyroid eye disease (TED).

METHODS

The orbital samples from 12 healthy controls and 29 TED patients (active group, n=12; inactive group, n=17) were analyzed. Total lymphocytes, CD3+T cells, CD4+T cells, CD8+ T cells, CD3+CD4+CD8+T cells (double-positive (DPT) T-cells), CD3+CD4-CD8-T cells (double negative (DNT) T-cells), B cells, natural killer (NK) cells and NKT cells were counted on flow cytometry. Correlations between the number of orbital immune cells and clinical activity score (CAS) were analyzed.

RESULTS

Age was greater in active than inactive TED patients, and in inactive TED patients than in controls (all P<0.05). TED duration was shorter in active than inactive patients (all P<0.05). FT3 and TSH levels were higher in controls than in active TED patients (P<0.05). There was no significant difference in TRAb level between active and inactive patients. There were no significant differences in smoking status, gender or FT4 level between the 3 groups (all P>0.05). The numbers of orbital total lymphocytes, CD3+ T cells, CD4+ T cells, CD8+ T cells, DNT cells, NK cells, NKT cells and CD4+/CD8+ T cells in active TED patients were significantly higher than in inactive patients and controls (all P<0.05). After adjusting for age and TED duration, the number of CD3+ T cells, CD4+ T cells, CD8+ T cells, NK cells and NKT cells were independent predictors of TED activity (P=0.03, OR=1.19; P=0.04, OR=1.69; P=0.03, OR=1.48; P=0.04, OR=2.08; P=0.03, OR=2.89, respectively).

CONCLUSIONS

Numerous immunoinflammatory cells were observed in the orbits of both active and inactive TED patients and in controls, but expression was highest in active TED patients. CD4+ T cell, CD8+ T cell, NK cell, and NKT cell counts were independent factors for the CAS in TED.

Molecular profiling of skin cells identifies distinct cellular signatures in radiation-induced skin injury across various stages in the murine dataset

BACKGROUND

Radiation-induced skin injury (RISI) commonly manifests in cancer patients undergoing radiotherapy (RT). However, a universally accepted standard for treating radiation injury has not yet been established. Our objective was to provide a detailed molecular overview of skin pre- and post-radiation therapy, aiming to enhance our understanding of the subclusters and molecular mechanisms contributing to radiodermatitis.

METHODS

C57BL/6 mice were subjected to a single fraction (20 Gy) of RT targeting the right dorsal skin. We then employed integrated single-cell RNA sequencing (scRNA-seq) to analyze skin samples from mice at 7 and 30 days after radiation exposure, as well as from non-irradiated mice. The Seurat analysis pipeline, Cellchat, SCP, and ssGSEA were used to define the cell types and mechanisms involved in radiation-induced skin injury. Reverse transcription polymerase chain reaction (RT-PCR), multiplex immunofluorescent staining, and other datasets (GSE130183, GSE193564, and GSE193807) were used to validate our findings.

RESULTS

Thirty-two distinct cell clusters encompassing 71,412 cells were identified. We discovered that cycling keratinocytes (KCs), with the BMP signaling pathway enriched, could activate the Wnt pathway, as well as the SMAD pathways, driving the wound healing and fibrosis processes in RISI. Terminally differentiated secretory-papillary fibroblasts (Fibs) are capable of attracting immune cells, which contributes to the pathogenesis of RISI. Lymphatic endothelial cells (ECs) with pro-inflammatory properties play a critical role in the pathogenesis of RISI by facilitating leukocyte migration. Our analysis also highlighted enhanced ligand-receptor interactions, notably the interactions between chemokines like CXCL10, CCL2, and ACKR1, across subclusters of inflammatory KCs, Fibs, ECs, and immune cells, underscoring their pivotal role in leukocyte recruitment in RISI.

CONCLUSIONS

Cycling KCs, secretory-papillary Fibs, and lymphatic ECs play critical roles in RISI progression. Targeting the interactions of these subclusters with immune cells might help improve the severity of RISI. Furthermore, our study provides a valuable resource for understanding the interactions among immune cells in the context of RISI.

Identifying Multiomic Signatures of X-Linked Retinoschisis-Derived Retinal Organoids and Mice Harboring Patient-Specific Mutation Using Spatiotemporal Single-Cell Transcriptomics

X-linked retinoschisis (XLRS) is an inherited retinal disorder with severe retinoschisis and visual impairments. Multiomics approaches integrate single-cell RNA-sequencing (scRNA-seq) and spatiotemporal transcriptomics (ST) offering potential for dissecting transcriptional networks and revealing cell-cell interactions involved in biomolecular pathomechanisms. Herein, a multimodal approach is demonstrated combining high-throughput scRNA-seq and ST to elucidate XLRS-specific transcriptomic signatures in two XLRS-like models with retinal splitting phenotypes, including genetically engineered (Rs1emR209C) mice and patient-derived retinal organoids harboring the same patient-specific p.R209C mutation. Through multiomics transcriptomic analysis, the endoplasmic reticulum (ER) stress/eukryotic initiation factor 2 (eIF2) signaling, mTOR pathway, and the regulation of eIF4 and p70S6K pathways are identified as chronically enriched and highly conserved disease pathways between two XLRS-like models. Western blots and proteomics analysis validate the occurrence of unfolded protein responses, chronic eIF2α signaling activation, and chronic ER stress-induced apoptosis. Furthermore, therapeutic targeting of the chronic ER stress/eIF2α pathway activation synergistically enhances the efficacy of AAV-mediated RS1 gene delivery, ultimately improving bipolar cell integrity, postsynaptic transmission, disorganized retinal architecture, and electrophysiological responses. Collectively, the complex transcriptomic signatures obtained from Rs1emR209C mice and patient-derived retinal organoids using the multiomics approach provide opportunities to unravel potential therapeutic targets for incurable retinal diseases, such as XLRS.

Transcriptomic profiling of thyroid eye disease orbital fat demonstrates differences in adipogenicity and IGF-1R pathway

Despite recent advances in the treatment of thyroid eye disease thyroid-related eye disease (TED), marked gaps remain in our understanding of the underlying molecular mechanisms, particularly concerning the insulin-like growth factor-1 receptor (IGF-1R) pathway. To dissect the pathophysiology of TED, we used single-nucleus RNA-Seq to analyze orbital fat specimens from both patients with TED and matched individuals acting as controls. The analysis demonstrated a marked increase in the proportion of fibroblasts transitioning to adipogenesis in the orbital fat of patients with TED compared with that in control patients. This was associated with diverse alterations in immune cell composition. Significant alterations in the IGF-1R signaling pathway were noted between TED specimens and those from control patients, indicating a potential pathological mechanism driven by IGF-1R signaling abnormalities. Additionally, our data showed that linsitinib, a small-molecule inhibitor of IGF-1R, effectively reduced adipogenesis in TED orbital fibroblasts in vitro, suggesting its potential utility as a therapeutic agent. Our findings reveal that, beyond immune dysfunction, abnormal IGF-1R signaling leading to enhanced adipogenesis is a crucial pathogenic mechanism in TED.

Role of genetics and epigenetics in Graves' orbitopathy

Objectives

The pathogenesis of Graves' orbitopathy (GO) remains to be fully elucidated. Here, we reviewed the role of genetics and epigenetics.

Design

We conducted a PubMed search with the following keywords: GO, thyroid eye disease; or Graves' ophthalmopathy; or thyroid-associated ophthalmopathy; and: genetic, or epigenetic, or gene expression, or gene mutation, or gene variant, or gene polymorphism, or DNA methylation, or DNA acetylation. Articles in which whole DNA and/or RNA sequencing, proteome, and methylome analyses were performed were chosen.

Results

The different prevalence of GO in the two sexes, as well as racial differences, suggest that genetics play a role in GO pathogenesis. In addition, the long-lasting phenotype of GO and patient-derived orbital fibroblasts suggests a genetic or epigenetic mechanism. Although no genes have been found to confer a specific risk for GO, differential gene expression has been reported in orbital fibroblasts from GO patients vs control fibroblasts, suggesting that an epigenetic mechanism may be involved. In this regard, a different degree of DNA methylation, which affects gene expression, has been found between GO and control fibroblasts, which was confirmed by whole methylome analysis. Histone acetylation and deacetylation, which also affect gene expression, remain to be investigated.

Conclusions

Although no pathogenic gene variants have been reported, epigenetic mechanisms elicited by an initial autoimmune insult seem to be needed for differential gene expression to occur and, thus, for GO to develop and persist over time.

Dynamic transition of Tregs to cytotoxic phenotype amid systemic inflammation in Graves' ophthalmopathy

Graves' disease (GD) is an autoimmune condition that can progress to Graves' ophthalmopathy (GO), leading to irreversible damage to orbital tissues and potential blindness. The pathogenic mechanism is not fully understood. In this study, we conducted single-cell multi-omics analyses on healthy individuals, patients with GD without GO, newly diagnosed patients with GO, and treated patients with GO. Our findings revealed gradual systemic inflammation during GO progression, marked by overactivation of cytotoxic effector T cell subsets, and expansion of specific T cell receptor clones. Importantly, we observed a decline in the immunosuppressive function of activated Treg (aTreg) accompanied by a cytotoxic phenotypic transition. In vitro experiments revealed that dysfunction and transition of GO-autoreactive Treg were regulated by the yin yang 1 (YY1) upon secondary stimulation of thyroid stimulating hormone receptor (TSHR) under inflammatory conditions. Furthermore, adoptive transfer experiments of the GO mouse model confirmed infiltration of these cytotoxic Treg into the orbital lesion tissues. Notably, these cells were found to upregulate inflammation and promote pathogenic fibrosis of orbital fibroblasts (OFs). Our results reveal the dynamic changes in immune landscape during GO progression and provide direct insights into the instability and phenotypic transition of Treg, offering potential targets for therapeutic intervention and prevention of autoimmune diseases.

Multi-Omics Approaches to Discover Biomarkers of Thyroid Eye Disease: A Systematic Review

Thyroid eye disease (TED) is an organ-specific autoimmune disorder that significantly impacts patients' visual function, appearance, and well-being. Despite existing clinical evaluation methods, there remains a need for objective biomarkers to facilitate clinical management and pathogenesis investigation. Rapid advances in multi-omics technologies have enabled the discovery and development of more informative biomarkers for clinical use. This systematic review synthesizes the current landscape of multi-omics approaches in TED research, highlighting the potential of genomics, transcriptomics, proteomics, metabolomics, and microbiomics to uncover novel biomarkers. Our review encompasses 69 studies involving 1,363 TED patients and 1,504 controls, revealing a wealth of biomarker candidates across various biological matrices. The identified biomarkers reflect alterations in gene expression, protein profiles, metabolic pathways, and microbial compositions, underscoring the systemic nature of TED. Notably, the integration of multi-omics data has been pivotal in enhancing our understanding of TED's molecular mechanisms and identifying diagnostic and prognostic markers with clinical potential.

Single-cell transcriptomics in thyroid eye disease

Thyroid eye disease (TED) is a poorly understood autoimmune condition affecting the retroorbital tissue. Tissue inflammation, expansion, and fibrosis can potentially lead to debilitating sequelae such as vision loss, painful eye movement, proptosis, and eyelid retraction. Current treatment modalities for TED include systemic glucocorticoids, thioamides, methimazole, teprotumumab, beta-blockers, and radioactive iodine; however, it has been reported that up to 10%-20% of TED patients relapse after treatment withdrawal and 20%-30% are unresponsive to mainstay therapy for reasons that have yet to be more clearly elucidated. In the past 4 years, vision researchers have harnessed high-throughput single-cell RNA sequencing to elucidate the diversity of cell types and molecular mechanisms driving the pathogenesis of TED at single-cell resolution. Such studies have provided unprecedented insight regarding novel biomarkers and therapeutic targets in TED. This timely review summarizes recent breakthroughs and emerging opportunities for using single-cell and single-nuclei transcriptomic data to characterize this highly complex disease state. We also provide an overview of current challenges and future applications of this technology to potentially improve patient quality of life and facilitate reversal of disease endpoints.

A combined transcriptomics and proteomics approach reveals S100A4 as a potential biomarker for Graves' orbitopathy

Background

There are no reliable biomarkers to identify Graves' disease patients who will develop severe Graves' orbitopathy (GO). We hypothesize that integrating various omics platforms can enhance our understanding of disease mechanisms and uncover potential biomarkers. This study aimed to (1) elucidate the differential gene expression profile of orbital fibroblasts in GO during early adipogenesis to better understand disease mechanisms and (2) compare tear protein profiles from our earlier study and the transcriptome profiles of orbital fibroblasts (OFs) to identify possible biomarkers of the disease.

Methods

OFs were grown from orbital adipose tissue obtained from nine GO patients (three for discovery and six for validation experiments). Total RNA was extracted from OFs on day 0 as the baseline for each sample and from differentiated OFs on days 4 and 8. Protein-protein interaction (PPI) analysis and functional enrichment analysis were also carried out. The differentially expressed genes (DEGs) from the RNA sequencing experiments were then compared to the full tear proteome profile from the author's previous study, which examined the tear protein changes of GO patients based on fold change > 1.6 or < -1.6. FDR < 0.05 was applied within all datasets. Further validation of S100 calcium-binding protein A4 (S100A4) downregulation in GO was performed via quantitative real-time PCR (qPCR).

Results

The whole transcriptomic analysis revealed 9 upregulated genes and 15 downregulated genes in common between the discovery and validation experiments. From the PPI network analysis, an interaction network containing six identified DEGs (ALDH2, MAP2K6, MT2A, SOCS3, S100A4, and THBD) was observed. The functional enrichment network analysis identified a set of genes related to oxysterol production. S100A4 was found to be consistently downregulated in both our transcriptome studies and the full-tear proteome profile from the author's previous study.

Conclusion

Our study identified several DEGs and potential gene pathways in GO patients, which concurred with the results of other studies. Tear S100A4 may serve as a biomarker for the propensity to develop thyroid eye disease (TED) in patients with autoimmune thyroid disease (AITD) before clinical manifestation and should be confirmed in future studies.

Associations between immune cell traits and autoimmune thyroid diseases: a bidirectional two-sample mendelian randomization study

Autoimmune thyroid diseases (AITDs), mainly including Graves' disease (GD) and Hashimoto's thyroiditis (HT), are common autoimmune disorders characterized by abnormal immune responses targeting the thyroid gland. We conducted a bidirectional two-sample MR analysis using the largest dataset of peripheral immune cell phenotypes from Sardinia, and the AITD dataset from the 10th round of the FinnGen and the UK Biobank project. Instrumental variables (IVs) were rigorously selected based on the three assumptions of MR and analyzed using the Wald ratio, inverse-variance weighted (IVW), MR-Egger, and weighted median methods. Additionally, sensitivity analyses were performed using Cochrane's Q, the Egger intercept, the MR-PRESSO, and the leave-one-out (LOO) method to ensure the robustness of the results. The Steiger test was utilized to identify and exclude potential reverse causation. The results showed that 3, 3, and 11 immune cell phenotypes were significantly associated with the risk of AITD. In GD, the proportion of naive CD4-CD8- (DN) T cells in T cells and the proportion of terminally differentiated CD4+T cells in T cells showed the strongest inducing and protective effects, respectively. In HT, lymphocyte count and CD45 on CD4+T cells showed the strongest inducing and protective effects, respectively. In autoimmune hypothyroidism, CD127 CD8+T cell count and terminally differentiated DN T cell count exhibited the strongest inducing and protective effects, respectively. Through MR analysis, our study provides direct genetic evidence of the impact of immune cell traits on AITD risk and lays the groundwork for potential therapeutic and diagnostic target discovery.

The whole blood DNA methylation of RAB8A and RAP1A in autoimmune thyroiditis: evidence and validation of iodine exposure in a population from different water iodine areas

Our study aimed to identify and verify G protein-related methylated genes in AIT patients, while also investigate those genes in AIT patients exposed to iodine in different water iodine areas. Different areas were classified by median water iodine (MWI) concentrations: Iodine-Fortified Areas (IFA, MWI<10µg/L), Iodine-Adequate Areas (IAA, 40≤MWI≤100 µg/L), and Iodine-Excessive Areas (IEA, MWI>100 µg/L). We studied 176 AIT cases and 176 controls, with 89, 40, and 47 pairs in IFA, IAA, and IEA, respectively. Using the Illumina Human Methylation 850k BeadChip, we identified candidate methylated genes. MethylTargetTM and QRT-PCR validated DNA methylation and mRNA expression. Results showed hypomethylation and high expression of RAB8A and RAP1A in all 176 AIT cases. RAB8A's CpG sites were mainly hypomethylated in IFA and IEA, while RAP1A's sites were primarily hypomethylated in IEA. This study underscores how water iodine exposure may influence RAB8A and RAP1A methylation in AIT.

Immune checkpoints: new insights into the pathogenesis of thyroid eye disease

Thyroid eye disease (TED) is a disfiguring autoimmune disease characterized by changes in the orbital tissues and is caused by abnormal thyroid function or thyroid-related antibodies. It is the ocular manifestation of Graves' disease. The expression of thyroid-stimulating hormone receptor (TSHR) and the insulin-like growth factor-1 receptor (IGF-1 R) on the cell membrane of orbital fibroblasts (OFs) is responsible for TED pathology. Excessive inflammation is caused when these receptors in the orbit are stimulated by autoantibodies. CD34+ fibrocytes, found in the peripheral blood and orbital tissues of patients with TED, express immune checkpoints (ICs) like MHC II, B7, and PD-L1, indicating their potential role in presenting antigens and regulating the immune response in TED pathogenesis. Immune checkpoint inhibitors (ICIs) have significantly transformed cancer treatment. However, it can also lead to the occurrence of TED in some instances, suggesting the abnormality of ICs in TED. This review will examine the overall pathogenic mechanism linked to the immune cells of TED and then discuss the latest research findings on the immunomodulatory role of ICs in the development and pathogenesis of TED. This will offer fresh perspectives on the study of pathogenesis and the identification of potential therapeutic targets.

Single-cell BCR and transcriptome analysis reveals peripheral immune signatures in patients with thyroid-associated ophthalmopathy

Thyroid-associated ophthalmopathy (TAO) is the most prevalent orbital disease in adults caused by an autoimmune disorder, which can lead to disfigurement and vision impairment. Developing effective treatments for this condition presents challenges due to our limited understanding of its underlying immune aberrations. In this study, we profiled the immune components in the peripheral blood of patients with TAO as well as healthy individuals, utilizing single-cell RNA sequencing and B-cell receptor repertoires (BCR) analysis. We observed a significant reduction in the proportions of regulatory B cells (Bregs) and type 2 conventional dendritic cells (DCs) in patients with TAO during the active phase. Conversely, there was a significant increase in the proportion of type 1 DCs. Further analysis of cell differentiation trajectory revealed potential impairment in the transition of B cells towards Breg phenotype during the active phase of TAO. Besides, the activation process of TAO appeared to involve inflammation and immune dysfunction, as indicated by the dynamic changes in the activities of key regulators. The abnormalities in the peripheral immune system, such as the reduced capacity of Bregs to suppress inflammation, were primarily driven by the enhanced interaction among Breg, DCs, and monocytes (i.e., CD22-PTPRC and BTLA-TNFRSF14). Collectively, our findings offer a comprehensive insight into the molecular regulation and cellular reconfiguration during the active phase of TAO at the single-cell level, in order to explore the pathogenesis of TAO and provide new ideas for the future treatment of TAO.

CD169+ classical monocyte as an important participant in Graves' ophthalmopathy through CXCL12-CXCR4 axis

Patients with Graves' disease (GD) can develop Graves' ophthalmopathy (GO), but the underlying pathological mechanisms driving this development remain unclear. In our study, which included patients with GD and GO, we utilized single-cell RNA sequencing (scRNA-seq) and multiplatform analyses to investigate CD169+ classical monocytes, which secrete proinflammatory cytokines and are expanded through activated interferon signaling. We found that CD169+ clas_mono was clinically significant in predicting GO progression and prognosis, and differentiated into CD169+ macrophages that promote inflammation, adipogenesis, and fibrosis. Our murine model of early-stage GO showed that CD169+ classical monocytes accumulated in orbital tissue via the Cxcl12-Cxcr4 axis. Further studies are needed to investigate whether targeting circulating monocytes and the Cxcl12-Cxcr4 axis could alleviate GO progression.

Identification of immune-related regulatory networks and diagnostic biomarkers in thyroid eye disease

BACKGROUND

Thyroid eye disease (TED) is an orbit-associated autoimmune inflammatory disorder intricately linked to immune dysregulation. Complete pathogenesis of TED remains elusive. This work aimed to mine pathogenesis of TED from immunological perspective and identify diagnostic genes.

METHODS

Gene expression microarray data for TED patients were downloaded from Gene Expression Omnibus, immune-related genes (IRGs) were from ImmPort database, and TED-related transcription factors (TFs) were from Cirtrome Cancer database. Differential analysis, Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed. Regulatory networks of TFs and IRGs were constructed with Cytoscape. Diagnostic biomarkers in TED were identified through LASSO. Immune cell infiltration analysis was performed using CIBERSORT.

RESULTS

Twenty-three immune-related DEmRNAs were revealed and were primarily enriched in humoral immune response, positive regulation of inflammatory response, IL-17, and TNF pathways. Co-expression regulatory network included four TFs and 16 immune-related DEmRNAs. Seven diagnostic genes were identified, with Area Under the Curve (AUC) of 0.993 for training set and AUC value of 0.836 for validation set. TED patients exhibited elevated infiltration levels by macrophages M2, mast cells, and CD8 T cells among 22 immune cell types, whereas macrophages M2 and mast cells resting were significantly lower than normal group.

CONCLUSIONS

The seven feature genes had high diagnostic value for TED patients. Our work explored regulatory network and diagnostic biomarkers, laying theoretical basis for TED diagnosis and treatment.

High expression of ACKR1 predicts a good prognosis and suppresses sarcoma cell progression via regulating the tumor immune microenvironment

Sarcoma is a malignant tumor originating from mesenchymal tissue with a poor prognosis. Atypical chemokine receptor 1 (ACKR1) is found closely related to cancer progression. However, the effects of ACKR1 in soft tissue sarcoma have not been well investigated. Therefore, our present study is devoted to analyze the functions of ACKR1 in sarcoma progression and its potential mechanism. We detected the expression of ACKR1 in the Cancer Genome Atlas (TCGA)-pan-cancer database, TCGA-Sarcoma from TCGA databases, and GSE21122 from Gene Expression Omnibus (GEO) database. The relationships between ACKR1 expression, clinicopathological data, and survival status were evaluated in the TCGA-Sarcoma database. Moreover, overexpression negative control (OE-NC) and overexpression ACKR1 (OE-ACKR1) were used to further verify the effects of ACKR1 overexpression in the progression of sarcoma cells by using Reverse Transcription-Quantitative Polymerase Chain Reaction (RT-qPCR), cell counting kit-8 (CCK-8), 5-Ethyny-2'-Deoxyuridine (EdU), wound healing, transwell assay, and flow cytometry assays. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and gene set enrichment analysis (GSEA) analyses were carried out to explore the potential enriched biological process of ACKR1 expression in sarcoma. Furthermore, tumor-immune system interactions databases (TISIDB) were applied to further confirm the relations between ACKR1 and tumor immune microenvironment in sarcoma. Our study found that ACKR1 is downregulated in multiple cancers (including sarcoma), and low expression of ACKR1 is related to poor survival status in sarcoma. The biological experiments found that promoting expression of ACKR1 can suppress sarcoma cell proliferation, migration, invasion, promote cell apoptosis, and arrest cell cycle. The GO-KEGG, GSEA, and TISIDB analysis showed that ACKR1 is related to the tumor immune microenvironment. In conclusion, low expression of ACKR1 presented as an independent prognostic biomarker in sarcoma. Overexpression of ACKR1 can significantly suppress cell progression ability in sarcoma by regulating the immune microenvironment.

The Future Landscape of Endothelial Cells Research in Psoriasis: Bibliometric Analysis and Literature Review

Background

Psoriasis is a global health concern as a chronic inflammatory skin disease. Endothelial dysfunction has been implicated in psoriasis pathogenesis.

Objective

This study aims to explore the scientific literature on the relationship between psoriasis and endothelial cells using bibliometric analysis, identifying research trends and public interest in this topic.

Methods

We analyzed articles on the topic of endothelial cells and psoriasis in the Web of Science (WoS) Core Collection from 1987 to 2022, examining their distribution by publication year, country, organization, author, and journal. We used bibliometric software, including CiteSpace and R package bibliometrix, to visualize co-authorship relations, keyword citation burst analysis, co citation networks, keyword time zone map, burst references and cluster analysis.

Results

Our analysis included 993 publications. The bibliometric analysis revealed a steady increase in the number of publications on psoriasis and endothelial cells over the past decade. The United States was the leading contributor to this field. The Journal of Investigative Dermatology was the most high-yield publication journal. Burst references analysis identified key articles that have significantly influenced the field, including studies on the role of endothelial dysfunction in psoriasis pathogenesis and the association between psoriasis severity and cardiovascular outcomes. 9 clusters were grouped in the key-word citation network. "Expression", "inflammation", "endothelial growth factor" and "angiogenesis" were the research focuses, while "cardiovascular disease", "atherosclerosis", "endothelial dysfunction", and "oxidative stress" might be the future research hotspots.

Conclusion

This bibliometric analysis sheds light on the growing acknowledgement of the involvement of endothelial cells in psoriasis, with the United States taking the lead. It also emphasizes the necessity for additional research to unravel the underlying mechanisms connecting psoriasis, endothelial dysfunction, and cardiovascular comorbidities. Ultimately, this research will contribute to the development of enhanced management strategies for psoriasis patients.

Immunology of human fibrosis

Fibrosis, defined by the excess deposition of structural and matricellular proteins in the extracellular space, underlies tissue dysfunction in multiple chronic diseases. Approved antifibrotics have proven modest in efficacy, and the immune compartment remains, for the most part, an untapped therapeutic opportunity. Recent single-cell analyses have interrogated human fibrotic tissues, including immune cells. These studies have revealed a conserved profile of scar-associated macrophages, which localize to the fibrotic niche and interact with mesenchymal cells that produce pathological extracellular matrix. Here we review recent advances in the understanding of the fibrotic microenvironment in human diseases, with a focus on immune cell profiles and functional immune-stromal interactions. We also discuss the key role of the immune system in mediating fibrosis regression and highlight avenues for future study to elucidate potential approaches to targeting inflammatory cells in fibrotic disorders.

Analysis of immunogenic cell death in ascending thoracic aortic aneurysms based on single-cell sequencing data

Background

At present, research on immunogenic cell death (ICD) is mainly associated with cancer therapy. Little is known about the role of ICD in cardiovascular disease, especially in ascending thoracic aortic aneurysms (ATAA).

Method

ATAA single-cell RNA (scRNA) sequencing data were analyzed to identify the involved cell types and determine their transcriptomic characteristics. The chi-square test, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses, Gene Set Enrichment Analysis (GSEA), and CellChat for cell-to-cell communication analysis from the Gene Expression Omnibus (GEO) database were used.

Result

A total of 10 cell types were identified, namely, monocytes, macrophages, CD4 T/NK (CD4+ T cells and natural killer T cells), mast cells, B/Plasma B cells, fibroblasts, endothelial cells, cytotoxic T cells (CD8+ T cells, CTLs), vascular smooth muscle cells (vSMCs), and mature dendritic cells (mDCs). A large number of inflammation-related pathways were present in the GSEA results. A large number of ICD-related pathways were found in the KEGG enrichment analysis of differentially expressed genes in endothelial cells. The number of mDCs and CTLs in the ATAA group was significantly different from that in the control group. A total of 44 pathway networks were obtained, of which 9 were associated with ICD in endothelial cells (CCL, CXCL, ANNEXIN, CD40, IL1, IL6, TNF, IFN-II, GALECTIN). The most important ligand-receptor pair by which endothelial cells act on CD4 T/NK cells, CTLs and mDCs is CXCL12-CXCR4. The most important ligand-receptor pair by which endothelial cells act on monocytes and macrophages is ANXA1-FPR1. The most important ligand-receptor pair by which CD4 T/NK cells and CTLs act on endothelial cells is CCL5-ACKR1. The most important ligand-receptor pair that myeloid cells (macrophages, monocytes and mDCs) act on endothelial cells is CXCL8-ACKR1. Moreover, vSMCs and fibroblasts mainly promote inflammatory responses through the MIF signaling pathway.

Conclusion

ICD is present in ATAA and plays an important role in the development of ATAA. The target cells of ICD may be mainly endothelial cells, in which the aortic endothelial cell ACKR1 receptor can not only promote T-cell infiltration through the CCL5 ligand but also promote myeloid cell infiltration through the CXCL8 ligand. ACKR1 and CXCL12 may become target genes for ATAA drug therapy in the future.