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Mobile DNA Jun 2024Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with an unpredictable course of recurrent exacerbations alternating with more stable disease. SLE is...
BACKGROUND
Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with an unpredictable course of recurrent exacerbations alternating with more stable disease. SLE is characterized by broad immune activation and autoantibodies against double-stranded DNA and numerous proteins that exist in cells as aggregates with nucleic acids, such as Ro60, MOV10, and the L1 retrotransposon-encoded ORF1p.
RESULTS
Here we report that these 3 proteins are co-expressed and co-localized in a subset of SLE granulocytes and are concentrated in cytosolic dots that also contain DNA: RNA heteroduplexes and the DNA sensor ZBP1, but not cGAS. The DNA: RNA heteroduplexes vanished from the neutrophils when they were treated with a selective inhibitor of the L1 reverse transcriptase. We also report that ORF1p granules escape neutrophils during the extrusion of neutrophil extracellular traps (NETs) and, to a lesser degree, from neutrophils dying by pyroptosis, but not apoptosis.
CONCLUSIONS
These results bring new insights into the composition of ORF1p granules in SLE neutrophils and may explain, in part, why proteins in these granules become targeted by autoantibodies in this disease.
PubMed: 38937837
DOI: 10.1186/s13100-024-00324-x -
Journal of Translational Medicine Jun 2024Interstitial lung disease (ILD) is the primary cause of mortality in systemic sclerosis (SSc), an autoimmune disease characterized by tissue fibrosis. SSc-related ILD...
BACKGROUND
Interstitial lung disease (ILD) is the primary cause of mortality in systemic sclerosis (SSc), an autoimmune disease characterized by tissue fibrosis. SSc-related ILD (SSc-ILD) occurs more frequently in females aged 30-55 years, whereas idiopathic pulmonary fibrosis (IPF) is more prevalent in males aged 60-75 years. SSc-ILD occurs earlier than IPF and progresses rapidly. FCN1, FABP4, and SPP1 macrophages are involved in the pathogenesis of lung fibrosis; SPP1 macrophages demonstrate upregulated expression in both SSc-ILD and IPF. To identify the differences between SSc-ILD and IPF using single-cell analysis, clarify their distinct pathogeneses, and propose directions for prevention and treatment.
METHODS
We performed single-cell RNA sequencing on NCBI Gene Expression Omnibus (GEO) databases GSE159354 and GSE212109, and analyzed lung tissue samples across healthy controls, IPF, and SSc-ILD. The primary measures were the filtered genes integrated with batch correction and annotated cell types for distinguishing patients with SSc-ILD from healthy controls. We proposed an SSc-ILD pathogenesis using cell-cell interaction inferences, and predicted transcription factors regulating target genes using SCENIC. Drug target prediction of the TF gene was performed using Drug Bank Online.
RESULTS
A subset of macrophages activates the MAPK signaling pathway under oxidative stress. Owing to the lack of inhibitory feedback from ANNEXIN and the autoimmune characteristics, this leads to an earlier onset of lung fibrosis compared to IPF. During initial lung injury, fibroblasts begin to activate the IL6 pathway under the influence of SPP1 alveolar macrophages, but IL6 appears unrelated to other inflammatory and immune cells. This may explain why tocilizumab (an anti-IL6-receptor antibody) only preserves lung function in patients with early SSc-ILD. Finally, we identified BCLAF1 and NFE2L2 as influencers of MAPK activation in macrophages. Metformin downregulates NFE2L2 and could serve as a repurposed drug candidate.
CONCLUSIONS
SPP1 alveolar macrophages play a role in the profibrotic activity of IPF and SSc-ILD. However, SSc-ILD is influenced by autoimmunity and oxidative stress, leading to the continuous activation of MAPK in macrophages. This may result in an earlier onset of lung fibrosis than in IPF. Such differences could serve as potential research directions for early prevention and treatment.
Topics: Humans; Scleroderma, Systemic; Macrophages; Lung Diseases, Interstitial; Female; Male; Middle Aged; Adult; Idiopathic Pulmonary Fibrosis; Aged; Gene Expression Regulation; Single-Cell Analysis; Lung
PubMed: 38937794
DOI: 10.1186/s12967-024-05403-4 -
BMC Infectious Diseases Jun 2024Tuberculosis (TB), one of the leading causes of death worldwide, has a higher incidence among indigenous people. Albeit uncommon, autoimmune hemolytic anemia (AIHA) has...
BACKGROUND
Tuberculosis (TB), one of the leading causes of death worldwide, has a higher incidence among indigenous people. Albeit uncommon, autoimmune hemolytic anemia (AIHA) has been deemed a risk condition to develop mycobacterial infection, as a result of the immunosuppressive treatments. TB, in turn, can be a predisposing factor for secondary infections.
CASE PRESENTATION
Here we present a case of a 28-year-old indigenous woman from Colombia, previously diagnosed with AIHA and pulmonary TB. Despite various treatments, therapies and medical interventions, the patient died after severe medullary aplasia of multiple causes, including secondary myelotoxicity by immunosuppressive therapy and secondary disseminated infections, underlining infection by Staphylococcus aureus, Klebsiella pneumoniae and Candida glabrata, which were identified as drug-resistant microorganisms. Together, this led to significant clinical complications. Invasive aspergillosis was diagnosed at autopsy.
CONCLUSIONS
This report presents a rarely finding of AIHA followed by TB, and highlights the great challenges of dealing with co-infections, particularly by drug resistant pathogens. It also aims to spur governments and public health authorities to focus attention in the prevention, screening and management of TB, especially among vulnerable communities, such as indigenous people.
Topics: Humans; Female; Adult; Coinfection; Fatal Outcome; Anemia, Hemolytic, Autoimmune; Colombia; Klebsiella pneumoniae; Staphylococcus aureus; Candida glabrata; Tuberculosis, Pulmonary; Staphylococcal Infections; Indigenous Peoples; Candidiasis
PubMed: 38937714
DOI: 10.1186/s12879-024-09557-w -
Communications Biology Jun 2024Distinct Natural Killer (NK)-like CD57 and PD-1 CD8 exhausted-like T cell populations (Tex) have both been linked to beneficial immunotherapy response in autoimmune type...
Distinct Natural Killer (NK)-like CD57 and PD-1 CD8 exhausted-like T cell populations (Tex) have both been linked to beneficial immunotherapy response in autoimmune type 1 diabetes (T1D) patients. The origins and relationships between these cell types are poorly understood. Here we show that while PD-1 and CD57 Tex populations are epigenetically similar, CD57 Tex cells display unique increased chromatin accessibility of inhibitory Killer Cell Immunoglobulin-like Receptor (iKIR) and other NK cell genes. PD-1 and CD57 Tex also show reciprocal expression of Inhibitory Receptors (IRs) and iKIRs accompanied by chromatin accessibility of Tcf1 and Tbet transcription factor target sites, respectively. CD57 Tex show unappreciated gene expression heterogeneity and share clonal relationships with PD-1 Tex, with these cells differentiating along four interconnected lineage trajectories: Tex-PD-1, Tex-CD57, Tex-Branching, and Tex-Fluid. Our findings demonstrate new relationships between Tex-like populations in human autoimmune disease and suggest that modulating common precursor populations may enhance response to autoimmune disease treatment.
Topics: Diabetes Mellitus, Type 1; Humans; CD8-Positive T-Lymphocytes; Killer Cells, Natural; Programmed Cell Death 1 Receptor; CD57 Antigens; Cell Lineage; Hepatocyte Nuclear Factor 1-alpha; Female; Male; Adult
PubMed: 38937521
DOI: 10.1038/s42003-024-06456-3 -
Nature Communications Jun 2024Progressive lung fibrosis is associated with poorly understood aging-related endothelial cell dysfunction. To gain insight into endothelial cell alterations in lung...
Progressive lung fibrosis is associated with poorly understood aging-related endothelial cell dysfunction. To gain insight into endothelial cell alterations in lung fibrosis we performed single cell RNA-sequencing of bleomycin-injured lungs from young and aged mice. Analysis reveals activated cell states enriched for hypoxia, glycolysis and YAP/TAZ activity in ACKR1+ venous and TrkB+ capillary endothelial cells. Endothelial cell activation is prevalent in lungs of aged mice and can also be detected in human fibrotic lungs. Longitudinal single cell RNA-sequencing combined with lineage tracing demonstrate that endothelial activation resolves in young mouse lungs but persists in aged ones, indicating a failure of the aged vasculature to return to quiescence. Genes associated with activated lung endothelial cells states in vivo can be induced in vitro by activating YAP/TAZ. YAP/TAZ also cooperate with BDNF, a TrkB ligand that is reduced in fibrotic lungs, to promote capillary morphogenesis. These findings offer insights into aging-related lung endothelial cell dysfunction that may contribute to defective lung injury repair and persistent fibrosis.
Topics: Animals; Endothelial Cells; Aging; Bleomycin; Humans; Mice; Pulmonary Fibrosis; Lung; Lung Injury; Receptor, trkB; Mice, Inbred C57BL; Brain-Derived Neurotrophic Factor; YAP-Signaling Proteins; Male; Single-Cell Analysis; Adaptor Proteins, Signal Transducing; Female; Disease Models, Animal
PubMed: 38937456
DOI: 10.1038/s41467-024-49545-x -
Annals of the Rheumatic Diseases Jun 2024Systemic lupus erythematosus (SLE) shows a marked female bias in prevalence. X chromosome inactivation (XCI) is the mechanism which randomly silences one X chromosome to...
OBJECTIVES
Systemic lupus erythematosus (SLE) shows a marked female bias in prevalence. X chromosome inactivation (XCI) is the mechanism which randomly silences one X chromosome to equalise gene expression between 46, XX females and 46, XY males. Though XCI is expected to result in a random pattern of mosaicism across tissues, some females display a significantly skewed ratio in immune cells, termed XCI-skew. We tested whether XCI was abnormal in females with SLE and hence contributes to sexual dimorphism.
METHODS
We assayed XCI in whole blood DNA in 181 female SLE cases, 796 female healthy controls and 10 twin pairs discordant for SLE. Using regression modelling and intra-twin comparisons, we assessed the effect of SLE on XCI and combined clinical, cellular and genetic data via a polygenic score to explore underlying mechanisms.
RESULTS
Accommodating the powerful confounder of age, XCI-skew was reduced in females with SLE compared with controls (p=1.3×10), with the greatest effect seen in those with more severe disease. Applying an XCI threshold of >80%, we observed XCI-skew in 6.6% of SLE cases compared with 22% of controls. This difference was not explained by differential white cell counts, medication or genetic susceptibility to SLE. Instead, XCI-skew correlated with a biomarker for type I interferon-regulated gene expression.
CONCLUSIONS
These results refute current views on XCI-skew in autoimmunity and suggest, in lupus, XCI patterns of immune cells reflect the impact of disease state, specifically interferon signalling, on the haematopoietic stem cells from which they derive.
PubMed: 38937070
DOI: 10.1136/ard-2024-225585 -
Journal of Thrombosis and Haemostasis :... Jun 2024Acquired hemophilia A (AHA) is an autoimmune bleeding disorder caused by neutralizing antibodies against coagulation factor VIII (FVIII). Immunosuppressive therapy (IST)...
BACKGROUND
Acquired hemophilia A (AHA) is an autoimmune bleeding disorder caused by neutralizing antibodies against coagulation factor VIII (FVIII). Immunosuppressive therapy (IST) is standard of care to eradicate autoantibody production and protect from further bleeding but carries a risk of severe infection and mortality in frail patients with AHA. Recently, emicizumab has been studied for its potential to reduce the need for early and aggressive IST.
OBJECTIVE
To compare outcomes of two studies that used either IST (GTH-AH 01/2010; n=101) or prophylaxis with emicizumab (GHT-AHA-EMI; n=47) early after diagnosis of AHA.
METHODS
Baseline characteristics were balanced by propensity score matching. Primary endpoint was the rate of clinically relevant new bleeds during the first 12 weeks; secondary endpoints were adverse events and overall survival.
RESULTS
The negative binominal model-based bleeding rate was 68% lower with emicizumab as compared with IST (incident rate ratio 0.325, 95% confidence interval (CI) 0.182-0.581). No difference was apparent in the overall frequency of infections (emicizumab 21%, IST 29%) during the first 12 weeks, but infections were less often fatal in emicizumab treated patients (0%) compared with IST treated patients (11%). Thromboembolic events occurred less often with emicizumab (2%) than IST (7%). Overall survival after 24 weeks was better with emicizumab (90% versus 76%, HR 0.44; 95% CI 0.24-0.81).
CONCLUSION
Using emicizumab instead of IST in the early phase after initial diagnosis of AHA reduced bleeding and fatal infections, and improved overall survival.
PubMed: 38936699
DOI: 10.1016/j.jtha.2024.06.010 -
Medical Mycology Jun 2024This systematic review evaluates the current global impact of invasive infections caused by Pneumocystis jirovecii (principally pneumonia: PJP), and was carried out to...
Features and global impact of invasive fungal infections caused by Pneumocystis jirovecii: A systematic review to inform the World Health Organization fungal priority pathogens list.
This systematic review evaluates the current global impact of invasive infections caused by Pneumocystis jirovecii (principally pneumonia: PJP), and was carried out to inform the World Health Organization Fungal Priority Pathogens List. PubMed and Web of Science were used to find studies reporting mortality, inpatient care, complications/sequelae, antifungal susceptibility/resistance, preventability, annual incidence, global distribution, and emergence in the past 10 years, published from January 2011 to February 2021. Reported mortality is highly variable, depending on the patient population: In studies of persons with HIV, mortality was reported at 5%-30%, while in studies of persons without HIV, mortality ranged from 4% to 76%. Risk factors for disease principally include immunosuppression from HIV, but other types of immunosuppression are increasingly recognised, including solid organ and haematopoietic stem cell transplantation, autoimmune and inflammatory disease, and chemotherapy for cancer. Although prophylaxis is available and generally effective, burdensome side effects may lead to discontinuation. After a period of decline associated with improvement in access to HIV treatment, new risk groups of immunosuppressed patients with PJP are increasingly identified, including solid organ transplant patients.
Topics: Humans; Pneumocystis carinii; Invasive Fungal Infections; World Health Organization; Immunocompromised Host; Risk Factors; Global Health; Pneumonia, Pneumocystis; Antifungal Agents; Incidence
PubMed: 38935910
DOI: 10.1093/mmy/myae038 -
Journal of Microbiology and... Apr 2024Viral infectious diseases have always been a threat to human survival and quality of life, impeding the stability and progress of human society. As such, researchers... (Review)
Review
Viral infectious diseases have always been a threat to human survival and quality of life, impeding the stability and progress of human society. As such, researchers have persistently focused on developing highly efficient, low-toxicity antiviral drugs, whether for acute or chronic infectious diseases. This article presents a comprehensive review of the design concepts behind virus-targeted drugs, examined through the lens of antiviral drug mechanisms. The intention is to provide a reference for the development of new, virus-targeted antiviral drugs and guide their clinical usage.
PubMed: 38934770
DOI: 10.4014/jmb.2403.03008 -
Medical Education Online Dec 2024While objective clinical structured examination (OSCE) is a worldwide recognized and effective method to assess clinical skills of undergraduate medical students, the...
While objective clinical structured examination (OSCE) is a worldwide recognized and effective method to assess clinical skills of undergraduate medical students, the latest Ottawa conference on the assessment of competences raised vigorous debates regarding the future and innovations of OSCE. This study aimed to provide a comprehensive view of the global research activity on OSCE over the past decades and to identify clues for its improvement. We performed a bibliometric and scientometric analysis of OSCE papers published until March 2024. We included a description of the overall scientific productivity, as well as an unsupervised analysis of the main topics and the international scientific collaborations. A total of 3,224 items were identified from the Scopus database. There was a sudden spike in publications, especially related to virtual/remote OSCE, from 2020 to 2024. We identified leading journals and countries in terms of number of publications and citations. A co-occurrence term network identified three main clusters corresponding to different topics of research in OSCE. Two connected clusters related to OSCE performance and reliability, and a third cluster on student's experience, mental health (anxiety), and perception with few connections to the two previous clusters. Finally, the United States, the United Kingdom, and Canada were identified as leading countries in terms of scientific publications and collaborations in an international scientific network involving other European countries (the Netherlands, Belgium, Italy) as well as Saudi Arabia and Australia, and revealed the lack of important collaboration with Asian countries. Various avenues for improving OSCE research have been identified: i) developing remote OSCE with comparative studies between live and remote OSCE and issuing international recommendations for sharing remote OSCE between universities and countries; ii) fostering international collaborative studies with the support of key collaborating countries; iii) investigating the relationships between student performance and anxiety.
Topics: Humans; Clinical Competence; Educational Measurement; Bibliometrics; Education, Medical, Undergraduate; Reproducibility of Results; Students, Medical; Biomedical Research
PubMed: 38934534
DOI: 10.1080/10872981.2024.2370617