Definition of human autoimmunity--autoantibodies versus autoimmune disease

Autoimmune associated HLAs and T cell autoantigens exhibit common patterns across several autoimmune diseases

Approximately 80 autoimmune diseases have been identified, with only a few proteins targeted by the immune system in each disease. The rest of the human proteome remains unaffected, indicating that the selection of these specific proteins is not random. Most autoimmune diseases show strong genetic associations with HLA alleles, suggesting a critical role for antigen presentation in autoimmunity. In this study, we analyzed validated T cell epitopes and their associated HLAs from 21 autoimmune diseases, including multiple sclerosis, rheumatoid arthritis, and type 1 diabetes mellitus, using experimental data from the IEDB. We compared autoantigens to proteins not implicated in autoimmunity, investigated HLA binding motifs, and contrasted autoimmunogenic T cell epitopes with non-autoimmune T cell epitopes. Autoantigens, compared to other non-autoimmunogenic proteins, exhibited higher mRNA expression, greater abundance in disease-specific tissues, and were frequently found in exposed subcellular locations such as membranes and extracellular spaces. Disease-associated HLAs showed distinct binding motifs compared to other HLAs, but the autoimmunogenic epitopes themselves did not differ markedly from other T cell epitopes. Autoantigens were enriched on MHC class II presented peptides, and the self-peptides differed from those seen in non-autoimmune contexts. Our findings suggest that the interplay between specific HLA class II alleles and specific antigen features play a pivotal role in initiating autoimmune responses, while subsequent T cell activation likely follows typical immune mechanisms.

Association between breastfeeding and the risk of autoimmune diseases: A systematic review and meta-analysis

OBJECTIVES

Previous studies on the association between breastfeeding and autoimmune diseases risk have yielded inconsistent findings. This study employed a systematic review and meta-analysis to explore the effect of breastfeeding and its duration against autoimmune diseases.

METHODS

Six databases (PubMed, Web of Science, Embase, CINAHL, Cochrane Library, PsycINFO) were systematically searched from inception to September 24, 2024. Studies on the association between breastfeeding and rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), ulcerative colitis (UC), Crohn's disease (CD), multiple sclerosis (MS) and type 1 diabetes mellitus (T1D) published within this period were included. Dichotomous outcome data from multiple studies were subjected to a random-effects meta-analysis using the Mantel-Haenszel method to estimate the pooled effect size. The Newcastle-Ottawa Scale was employed to evaluate quality.

RESULTS

Of the 40 included studies (35 case-control studies and 5 cohort studies), 12 were stratified by the duration of breastfeeding. The combined effect showed a protective association between breastfeeding and a reduced risk of autoimmune diseases (OR = 0.80; 95 %CI: 0.72 to 0.89; P < 0.001). This protective effect was significant for RA (OR = 0.66; 95 %CI: 0.46 to 0.93; P = 0.018), MS (OR = 0.78; 95 % CI: 0.63 to 0.98; P = 0.030) and T1D (OR = 0.80; 95 %CI: 0.66 to 0.98; P = 0.028), and was more pronounced with breastfeeding duration of at least four months (OR = 0.81; 95 %CI: 0.72 to 0.90; P < 0.001).

CONCLUSION

Breastfeeding provides an overall protective effect against autoimmune diseases and a significant protective effect on RA, MS and T1D. This protective effect appears stronger with breastfeeding duration of at least 4 months. These results highlight the necessity of promoting breastfeeding and supporting related policies to improve infant health.

Conceptual Contextualization of Neutrophilic Dermatoses

ABSTRACT

Neutrophilic dermatoses are defined as inflammatory skin diseases characterized by sterile infiltration of polymorphonuclear neutrophils into various cutaneous layers. Although, in many cases, neutrophilic dermatoses represent the cutaneous counterpart of autoinflammatory diseases, this is not always the case, and there are other causes associated with this group of diseases, such as the administration of certain drugs or an underlying tumor. However, understanding the autoinflammatory context in which most of these entities develop, as well as their close relationship with autoimmunity, is key to comprehending their pathogenesis. In addition, understanding the mechanisms by which neutrophils migrate to the dermis and become activated is fundamental for interpreting the morphological findings of these biopsies. Finally, the description of a new group of neutrophilic dermatoses in recent years, in relation to keratinization disorders, has been crucial for understanding the best therapeutic approach for these difficult-to-manage entities.

Dissecting genetic regulation of metabolic coordination

Understanding genetic regulation of metabolism is critical for gaining insights into the causes of metabolic diseases. Traditional metabolome-based genome-wide association studies (mGWAS) focus on static associations between single nucleotide polymorphisms (SNPs) and metabolite levels, overlooking the changing relationships caused by genotypes within the metabolic network. Notably, some metabolites exhibit changes in correlation patterns with other metabolites under certain physiological conditions while maintaining their overall abundance level. In this manuscript, we develop Metabolic Differential-coordination GWAS (mdGWAS), an innovative framework that detects SNPs associated with the changing correlation patterns between metabolites and metabolic pathways. This approach transcends and complements conventional mean-based analyses by identifying latent regulatory factors that govern the system-level metabolic coordination. Through comprehensive simulation studies, mdGWAS demonstrated robust performance in detecting SNP-metabolite-metabolite associations. Applying mdGWAS to genotyping and mass spectrometry (MS)-based metabolomics data of the METabolic Syndrome In Men (METSIM) Study revealed novel SNPs and genes potentially involved in the regulation of the coordination between metabolic pathways.

Antinuclear Antibodies in Non-Rheumatic Diseases

Antinuclear antibodies (ANAs) are critical immunological markers commonly associated with various connective tissue diseases (CTDs). However, these autoantibodies are also detectable in healthy individuals, patients with non-rheumatic autoimmune diseases, those with viral infections, and subjects using specific medications (such as procainamide, hydralazine, and minocycline) that can lead to drug-induced ANA elevation. The standard method for ANA detection is indirect immunofluorescence, a process that requires precision and thoroughness as it assesses both titer and fluorescence patterns. Additionally, immunoblotting and enzyme-linked immunosorbent assay (ELISA) are recommended to identify specific ANAs precisely, highlighting the importance of precision in ANA detection. This review explores the advantages and limitations of current ANA detection methods. It also describes the clinical implications of ANA presence in non-rheumatic diseases, including autoimmune disorders, infectious conditions, non-autoimmune and non-infectious diseases, and autoimmune cutaneous diseases. The presence of elevated ANA titers in these contexts can complicate clinical decision-making, as the diagnostic value of ANA testing alone is limited in non-rheumatic conditions. However, despite these limitations, ANA remains a key component in diagnosing and prognosis systemic CTDs, as it can indicate disease activity, severity, and response to treatment, which is of utmost importance in rheumatology and internal medicine. This paper provides a comprehensive review of the role of ANA in non-rheumatic diseases. It focuses on ANA diagnostic and prognostic significance and offers valuable insights for clinical practice.

Early-life glucocorticoids accelerate lymphocyte count senescence in roe deer

Immunosenescence corresponds to the progressive decline of immune functions with increasing age. Although it is critical to understand what modulates such a decline, the ecological and physiological drivers of immunosenescence remain poorly understood in the wild. Among them, the level of glucocorticoids (GCs) during early life are good candidates to modulate immunosenescence patterns because these hormones can have long-term consequences on individual physiology. Indeed, GCs act as regulators of energy allocation to ensure allostasis, are part of the stress response triggered by unpredictable events and have immunosuppressive effects when chronically elevated. We used longitudinal data collected over two decades in two populations of roe deer (Capreolus capreolus) to test whether higher baseline GC levels measured within the first year of life were associated with a more pronounced immunosenescence and parasite susceptibility. We first assessed immunosenescence trajectories in these populations facing contrasting environmental conditions. Then, we found that juvenile GC levels can modulate lymphocyte trajectory. Lymphocyte depletion was accelerated late in life when GCs were elevated early in life. Although the exact mechanism remains to be elucidated, it could involve a role of GCs on thymic characteristics. In addition, elevated GC levels in juveniles were associated with a higher abundance of lung parasites during adulthood for individuals born during bad years, suggesting short-term negative effects of GCs on juvenile immunity, having in turn long-lasting consequences on adult parasite load, depending on juvenile environmental conditions. These findings offer promising research directions in assessing the carry-over consequences of GCs on life-history traits in the wild.

Seroprevalence of Toxoplasma gondii immunoglobulins and its association with systemic lupus erythematosus: A systematic review and meta-analysis

BACKGROUND

The exact cause of systemic lupus erythematosus (SLE) is still unknown. However, hormonal, genetic, and environmental factors may play significant roles in its development. Infection has been recognized as a crucial trigger for SLE development. Several studies have reported a higher prevalence of Toxoplasma gondii infections in patients with SLE than in healthy individuals. However, these results were inconsistent. Therefore, this study aimed to conduct a systematic review and meta-analysis of published studies to provide a definitive conclusion regarding the relationship between T. gondii infection and SLE.

MATERIALS AND METHODS

We conducted a comprehensive search across diverse databases using an array of search tools to uncover pertinent literature. Following the stringent application of the inclusion and exclusion criteria, we carefully selected the appropriate reports for our meta-analysis. Using Comprehensive Meta-Analysis software v4, we analyzed the data and determined the prevalence of antibodies against T. gondii in patients affected with SLE. To investigate the correlation between T. gondii seropositivity and SLE, we computed the risk ratios (RRs) and 95% confidence intervals (CI).

RESULTS

Eleven studies were considered eligible for inclusion in the present study. The prevalence of anti-IgG and IgM antibodies against T. gondii was 33.9% and 7.7%, respectively. A significant association between T. gondii IgG seropositivity and SLE was observed when compared to the controls (risk ratio = 2.14, 95% CI = 1.42 to 3.22, p = .000). However, IgM seropositivity against T. gondii was comparable between patients with SLE and healthy controls.

CONCLUSIONS

In summary, this study suggests that T. gondii IgG is more prevalent in patients with SLE than in healthy individuals in areas where T. gondii infections are more frequent. However, an exact cause-and-effect relationship still needs to be established. Therefore, additional research is necessary to validate these findings and to investigate the underlying mechanisms.

The role of neutrophils in autoimmune diseases

Historically, neutrophils have been primarily regarded as short-lived immune cells that act as initial responders to antibacterial immunity by swiftly neutralizing pathogens and facilitating the activation of adaptive immunity. However, recent evidence indicates that their roles are considerably more complex than previously recognized. Neutrophils comprise distinct subpopulations and can interact with various immune cells, release granular proteins, and form neutrophil extracellular traps. These functions are increasingly recognized as contributing factors to tissue damage in autoimmune diseases. This review comprehensively examines the physiological functions and heterogeneity of neutrophils, their interactions with other immune cells, and their significance in autoimmune diseases, including systemic lupus erythematosus, rheumatoid arthritis, antiphospholipid syndrome, antineutrophil cytoplasmic antibody-associated vasculitis, multiple sclerosis, and others. This review aims to provide a deeper understanding of the function of neutrophils in the development and progression of autoimmune disorders.

A Handle on Mass Coincidence Errors in De Novo Sequencing of Antibodies by Bottom-up Proteomics

Antibody sequences can be determined at 99% accuracy directly from the polypeptide product by using bottom-up proteomics techniques. Sequencing accuracy at the peptide level is limited by the isobaric residues leucine and isoleucine, incomplete fragmentation spectra in which the order of two or more residues remains ambiguous due to lacking fragment ions for the intermediate positions, and isobaric combinations of amino acids, of potentially different lengths, for example, GG = N and GA = Q. Here, we present several updates to Stitch (v1.5), which performs template-based assembly of de novo peptides to reconstruct antibody sequences. This version introduces a mass-based alignment algorithm that explicitly accounts for mass coincidence errors. In addition, it incorporates a postprocessing procedure to assign I/L residues based on secondary fragments (satellite ions, i.e., w-ions). Moreover, evidence for sequence assignments can now be directly evaluated with the addition of an integrated spectrum viewer. Lastly, input data from a wider selection of de novo peptide sequencing algorithms are allowed, now including Casanovo, PEAKS, Novor.Cloud, pNovo, and MaxNovo, in addition to flat text and FASTA. Combined, these changes make Stitch compatible with a larger range of data processing pipelines and improve its tolerance to peptide-level sequencing errors.

Biological changes in human B-cell line Ramos (RA.1) related to increasing doses of human parathyroid hormone

Background

The etiopathogenesis of autoimmune diseases is multifactorial, including hormonal factors. Remission of autoimmunity has been observed following treatment for concomitant hyperparathyroidism. Additionally, patients with autoimmune diseases have shown increased expression of parathyroid hormone receptor (PTH1R) and altered distribution of B cells subsets. Hence, this study aims to evaluate potential mechanisms and in vitro effects of PTH stimulation on B lymphocytes.

Methods

Using the human B-cell line Ramos (RA.1), various biological effects were evaluated with and without parathyroid hormone (PTH) stimulation at varying concentrations. Flow cytometry was employed to evaluate the phenotype of B lymphocytes based on IgD and CD38 expression, apoptosis induction via Annexin V and proliferation using CFSE. IgM production was quantified through ELISA, and Western blot analysis was performed to assess syk protein phosphorylation as an indicator of cell activation.

Results

Ramos cells (RA.1) evidenced a statistically significant change in the phenotype under human PTH stimulation, demonstrating an increased proportion of germinal centre cells (Bm3-Bm4) when stimulated with high concentrations of PTH.

Conclusions

The in vitro effects of PTH in B cells subsets align with previous findings of an altered phenotype in B lymphocytes expressing PTH1R among autoimmune disease patients, suggesting a potential role of this hormone in the pathophysiology of autoimmune diseases. However, further studies are necessary to elucidate the mechanisms by which PTH generates observed effects in B lymphocytes and to determine if PTH plays a role in autoimmunity.

Autoantibody Profiling Using Human Autoantigen Protein Array and AlphaScreen

Autoantibodies that recognize self-antigens are believed to have a close relationship with diseases such as autoimmune diseases, cancer, and lifestyle diseases. Analysis of autoantibodies is essential for investigating pathology mechanisms, diagnosis, and therapeutics of these diseases. We developed an autoantibody profiling assay using a cell-free synthesized protein array and high-throughput screening technology. Our assay system can sensitively detect interaction between recombinant antigen protein and autoantibody and efficiently analyze autoantibody profiling in patients' sera.

Oxidative modification of carbonic anhydrase by peroxynitrite trigger immune response in mice and rheumatic disease patients

BACKGROUND

Carbonic anhydrases (CA) are metalloenzymes with wide tissue distribution, involved in many important physiological processes, and in some rheumatic diseases, autoantibodies are formed against these enzymes. Recent studies have suggested that oxidative stress triggers anti-CA antibody formation. In this study, we aimed to investigate the effects of modification with oxidative/nitrosative stress end products on CA antigenicity in mice and the relationship between the modified CA autoantibodies and oxidant-antioxidant status in patients with rheumatoid arthritis (RA) and Sjögren's syndrome (SjS).

METHODS

CA I and CA II isoenzymes were isolated from human erythrocytes and modified with 4-hydroxynonenal (4-HNE), malondialdehyde (MDA), and peroxynitrite (PN). Balb-c mice were immunized with these agents to determine the effects of modification on CA antigenicity. The autoantibody titers of modified CA isoenzymes were detected in patients. In addition MDA, 4-HNE, 3-nitrotyrosine (3-NT), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) activities were measured to assess the oxidant-antioxidant status in patients.

RESULTS

Modifications of carbonic anhydrase with oxidative stress end products, HNE, MDA and PN, lead to alterations in the immune response to these enzymes in mice. It was found that HNE and MDA decreased the antigenicity while PN increased. In addition, PN-modified CA autoantibody levels were found to be significantly different in both RA and SjS patients compared to their controls (p<0.05).

CONCLUSIONS

PN modifications can also trigger an immune response against CA isoenzymes in mice, and PN-modified CA I and CA II autoantibody titers were found at a significantly high level in both RA and SjS patients.

The effects of Lactobacillus delbrueckii and Lactobacillus rhamnosus on cytokines and their related molecules: An ex vivo study on patients with systemic lupus erythematosus

Objectives

This study aimed to assess the ex vivo impact of Lactobacillus delbrueckii (L. delbrueckii) and Lactobacillus rhamnosus (L. rhamnosus) on inflammatory and anti-inflammatory cytokines as well as their related molecules on the peripheral blood mononuclear cells (PBMCs) of systemic lupus erythematosus (SLE) patients.

Patients and methods

This study was conducted with 20 newly diagnosed SLE patients (18 females, 2 males; mean age: 33.3±12.4 years; range, 18 to 68 years) between September 2017 and September 2018. Extracted PBMCs from each patient were divided into 4 cell groups in our study. Three cell groups act as treatment groups receiving L. rhamnosus (107 CFU/mL), L. delbrueckii (105 CFU/mL) or a mixture of both, and one group act as our untreated control group in the absence of any probiotic agents. All cell groups were cultured in RPMI 1460 medium for 48 h. Then, total RNA was extracted, and cDNA was synthesized.

Results

The gene expression levels of forkhead box P3 (FOXP3), transforming growth factor beta (TGF-β), interleukin (IL)-6, IL-10, and IL-2 were evaluated by a quantitative real-time polymerase chain reaction. The results revealed that expression levels of FOXP3, TGF-β, IL-10, and IL-2 increased and the level of IL-6 decreased in probiotics-receiving groups compared to the control group. Lactobacillus delbrueckii and L. rhamnosus enhanced the expression of regulatory T cell-related molecules such as FOXP3 and IL-2 and also increased the expression of IL-10. These probiotics also reduced the expression of IL-6 as proinflammatory cytokines in the PBMCs of SLE patients.

Conclusion

The results of the present study show that these probiotics could be effective in regulating the balance of cytokine gene expression ex vivo , and due to their beneficial effects, they can be an intriguing option in the production of new complement drugs for SLE.

Scorpion venom peptides: Molecular diversity, structural characteristics, and therapeutic use from channelopathies to viral infections and cancers

Animal venom is an important evolutionary innovation in nature. As one of the most representative animal venoms, scorpion venom contains an extremely diverse set of bioactive peptides. Scorpion venom peptides not only are 'poisons' that immobilize, paralyze, kill, or dissolve preys but also become important candidates for drug development and design. Here, the review focuses on the molecular diversity of scorpion venom peptides, their typical structural characteristics, and their multiple therapeutic or pharmaceutical applications in channelopathies, viral infections and cancers. Especially, the group of scorpion toxin TRPTx targeting transient receptor potential (TRP) channels is systematically summarized and worthy of attention because TRP channels play a crucial role in the regulation of homeostasis and the occurrence of diseases in human. We also further establish the potential relationship between the molecular characteristics and functional applications of scorpion venom peptides to provide a research basis for modern drug development and clinical utilization of scorpion venom resources.

Tumor-Associated and Systemic Autoimmunity in Pre-Clinical Breast Cancer among Post-Menopausal Women

Autoantibodies to tumor-associated antigens (anti-TAA) are potential biomarkers for breast cancer, but their relationship systemic autoimmunity as ascertained though antinuclear antibodies (ANA) is unknown and warrants consideration given the common occurrence of autoimmunity and autoimmune diseases among women. The relationship between anti-TAAs and ANA among women who were later diagnosed with breast cancer and others who remained cancer free in the Women's Health Initiative cohort. The study sample included 145 post-menopausal women with baseline ANA data. A total of 37 ANA-positive women who developed breast cancer (i.e., cases; mean time to diagnosis 6.8 years [SE 3.9]) were matched to a random sample of 36 ANA-negative cases by age and time to diagnosis. An age-matched control sample was selected including 35 ANA-positive and 37 ANA-negative women who did not develop breast cancer (i.e., controls; follow-up time ~13 years [SE 3]). Baseline sera were assessed for Immunoglobulin G (IgG) antibodies, measured by custom microarray for 171 breast and other cancer-associated TAA. We used linear regression to estimate cross-sectional associations of ANA with log-transformed anti-TAA among cases and controls. Most anti-TAA did not vary by ANA status. Two anti-TAA were elevated in ANA-positive compared to ANA-negative cases: anti-PGM3 (p = 0.004) and anti-TTN (p = 0.005, especially in cases up to 7 years before diagnosis, p = 0.002). Anti-TAA antibodies were not generally related to ANA, a common marker of systemic autoimmunity. Associations of ANA with particular antigens inducing autoimmunity prior to breast cancer warrant further investigation.

Patients with Systemic Juvenile Idiopathic Arthritis (SJIA) Show Differences in Autoantibody Signatures Based on Disease Activity

Systemic juvenile idiopathic arthritis (SJIA) is a severe rheumatic disease in children. It is a subgroup of juvenile idiopathic arthritis (JIA; MIM #604302), which is the most common rheumatic disease in children. The diagnosis of SJIA often comes with a significant delay, and the classification between autoinflammatory and autoimmune disease is still discussed. In this study, we analyzed the immunological responses of patients with SJIA, using human proteome arrays presenting immobilized recombinantly expressed human proteins, to analyze the involvement of autoantibodies in SJIA. Results from group comparisons show several differentially reactive antigens involved in inflammatory processes. Intriguingly, many of the identified antigens had a high reactivity against proteins involved in the NF-κB pathway, and it is also notable that many of the detected DIRAGs are described as dysregulated in rheumatoid arthritis. Our data highlight novel proteins and pathways potentially dysregulated in SJIA and offer a unique approach to unraveling the underlying disease pathogenesis in this chronic arthropathy.

A review of the auditory-gut-brain axis

Hearing loss places a substantial burden on medical resources across the world and impacts quality of life for those affected. Further, it can occur peripherally and/or centrally. With many possible causes of hearing loss, there is scope for investigating the underlying mechanisms involved. Various signaling pathways connecting gut microbes and the brain (the gut-brain axis) have been identified and well established in a variety of diseases and disorders. However, the role of these pathways in providing links to other parts of the body has not been explored in much depth. Therefore, the aim of this review is to explore potential underlying mechanisms that connect the auditory system to the gut-brain axis. Using select keywords in PubMed, and additional hand-searching in google scholar, relevant studies were identified. In this review we summarize the key players in the auditory-gut-brain axis under four subheadings: anatomical, extracellular, immune and dietary. Firstly, we identify important anatomical structures in the auditory-gut-brain axis, particularly highlighting a direct connection provided by the vagus nerve. Leading on from this we discuss several extracellular signaling pathways which might connect the ear, gut and brain. A link is established between inflammatory responses in the ear and gut microbiome-altering interventions, highlighting a contribution of the immune system. Finally, we discuss the contribution of diet to the auditory-gut-brain axis. Based on the reviewed literature, we propose numerous possible key players connecting the auditory system to the gut-brain axis. In the future, a more thorough investigation of these key players in animal models and human research may provide insight and assist in developing effective interventions for treating hearing loss.

Clinical and prognostic associations of autoantibodies recognizing adrenergic/muscarinic receptors in patients with heart failure

AIMS

The importance of autoantibodies (AABs) against adrenergic/muscarinic receptors in heart failure (HF) is not well-understood. We investigated the prevalence and clinical/prognostic associations of four AABs recognizing the M2-muscarinic receptor or the β1-, β2-, or β3-adrenergic receptor in a large and well-characterized cohort of patients with HF.

METHODS AND RESULTS

Serum samples from 2256 patients with HF from the BIOSTAT-CHF cohort and 299 healthy controls were analysed using newly established chemiluminescence immunoassays. The primary outcome was a composite of all-cause mortality and HF rehospitalization at 2-year follow-up, and each outcome was also separately investigated. Collectively, 382 (16.9%) patients and 37 (12.4%) controls were seropositive for ≥1 AAB (P = 0.045). Seropositivity occurred more frequently only for anti-M2 AABs (P = 0.025). Amongst patients with HF, seropositivity was associated with the presence of comorbidities (renal disease, chronic obstructive pulmonary disease, stroke, and atrial fibrillation) and with medication use. Only anti-β1 AAB seropositivity was associated with the primary outcome [hazard ratio (95% confidence interval): 1.37 (1.04-1.81), P = 0.024] and HF rehospitalization [1.57 (1.13-2.19), P = 0.010] in univariable analyses but remained associated only with HF rehospitalization after multivariable adjustment for the BIOSTAT-CHF risk model [1.47 (1.05-2.07), P = 0.030]. Principal component analyses showed considerable overlap in B-lymphocyte activity between seropositive and seronegative patients, based on 31 circulating biomarkers related to B-lymphocyte function.

CONCLUSIONS

AAB seropositivity was not strongly associated with adverse outcomes in HF and was mostly related to the presence of comorbidities and medication use. Only anti-β1 AABs were independently associated with HF rehospitalization. The exact clinical value of AABs remains to be elucidated.

Role of microbiota short-chain fatty acids in the pathogenesis of autoimmune diseases

There is emerging evidence that microbiota and its metabolites play an important role in helath and diseases. In this regard, gut microbiota has been found as a crucial component that influences immune responses as well as immune-related disorders such as autoimmune diseases. Gut bacterial dysbiosis has been shown to cause disease and altered microbiota metabolite synthesis, leading to immunological and metabolic dysregulation. Of note, microbiota in the gut produce short-chain fatty acids (SCFAs) such as acetate, butyrate, and propionate, and remodeling in these microbiota metabolites has been linked to the pathophysiology of a number of autoimmune disorders such as type 1 diabetes, multiple sclerosis, inflammatory bowel disease, rheumatoid arthritis, celiac disease, and systemic lupus erythematosus. In this review, we will address the most recent findings from the most noteworthy studies investigating the impact of microbiota SCFAs on various autoimmune diseases.

Moonlighting chromatin: when DNA escapes nuclear control

Extracellular chromatin, for example in the form of neutrophil extracellular traps (NETs), is an important element that propels the pathological progression of a plethora of diseases. DNA drives the interferon system, serves as autoantigen, and forms the extracellular scaffold for proteins of the innate immune system. An insufficient clearance of extruded chromatin after the release of DNA from the nucleus into the extracellular milieu can perform a secret task of moonlighting in immune-inflammatory and occlusive disorders. Here, we discuss (I) the cellular events involved in the extracellular release of chromatin and NET formation, (II) the devastating consequence of a dysregulated NET formation, and (III) the imbalance between NET formation and clearance. We include the role of NET formation in the occlusion of vessels and ducts, in lung disease, in autoimmune diseases, in chronic oral disorders, in cancer, in the formation of adhesions, and in traumatic spinal cord injury. To develop effective therapies, it is of utmost importance to target pathways that cause decondensation of chromatin during exaggerated NET formation and aggregation. Alternatively, therapies that support the clearance of extracellular chromatin are conceivable.

Serum autoantibodies and exploratory molecular pathways in rural miners: A pilot study

Introduction

The Southwestern United States (SWUS) has an extensive history of coal and metal mining, including uranium (U) mining. Lung diseases, including but not limited to, lung cancer and pulmonary fibrosis, have been studied extensively in miners due to occupational, dust-related exposures. However, high-throughput autoimmune biomarkers are largely understudied in miners, despite the fact that ore miners, such as U-miners, are at an increased risk for the development of autoimmune diseases such as systemic sclerosis and systemic lupus erythematosus (SLE). Additionally, there are current gaps in knowledge regarding which signaling pathways may play a role in occupational exposure-associated autoimmunity.

Methods

Most current and former miners in the SWUS live close to their previous workplaces, in remote areas, with limited access to healthcare. In this pilot study, by leveraging a mobile clinical platform for patient care and clinical outreach, we recruited 44 miners who self-identified as either U (n = 10) or non-U miners (n = 34) and received health screenings. Serum IgG and IgM autoantibodies against 128 antigens were assessed using a high-throughput molecular technique, as a preliminary health screening opportunity.

Results

Even when adjusting for age as a covariate, there was a significant (p < 0.05) association between self-reported U-mining exposure and biomarkers including IgM alpha-actinin, histones H2B, and H4, myeloperoxidase (MPO) and myelin basic protein. However, adjusting for age did not result in significant associations for IgG autoantibody production in U-miners. Bioinformatic pathway analysis revealed several altered signaling pathways between IgM and IgG autoantibodies among both U and non-U miners.

Conclusions

Further research is warranted regarding the mechanistic connection between U-exposure and autoantibody development, especially regarding histone-related alterations and IgM autoantibody production.

The increasing prevalence of autoimmunity and autoimmune diseases: an urgent call to action for improved understanding, diagnosis, treatment, and prevention

Autoimmunity is characterized by self-reactive immune components and autoimmune disease by autoimmunity plus pathology. Both autoimmunity and autoimmune diseases are dramatically increasing in many parts of the world, likely as a result of changes in our exposures to environmental factors. Current evidence implicates the momentous alterations in our foods, xenobiotics, air pollution, infections, personal lifestyles, stress, and climate change as causes for these increases. Autoimmune diseases have a major impact on the individuals and families they affect, as well as on our society and healthcare costs, and current projections suggest they may soon take their place among the predominant medical disorders. This necessitates that we increase the scope and scale of our efforts, and coordinate our resources and studies, to understand autoimmune disease risk factors and pathogeneses and improve our diagnostic, therapeutic, and preventive approaches, as the costs of inaction will be profound and far greater without such investments.

Curcumin-based nanotechnology approaches and therapeutics in restoration of autoimmune diseases

Autoimmune diseases usually arise as a result of an aberrant immune system attack on normal tissues of the body, which leads to a cascade of inflammatory reactions. The immune system employs different types of protective and anti-inflammatory cells for the regulation of this process. Curcumin is a known natural anti-inflammatory agent that inhibits pathological autoimmune processes by regulating inflammatory cytokines and their associated signaling pathways in immune cells. Due to the unstable nature of curcumin and its susceptibility to either degradation, or metabolism into other chemical entities (i.e., metabolites), encapsulation of this agent into various nanocarriers would appear to be an appropriate strategy for attaining greater beneficial effects from curcumin as it pertains to immunomodulation. Many studies have focused on the design and development of curcumin nanodelivery systems (micelles, dendrimers, and diverse nanocarriers) and are summarized in this review in order to obtain greater insight into novel drug delivery systems for curcumin and their suitability for the management of autoimmune diseases.

Anti-vinculin antibodies as a novel biomarker in Egyptian patients with systemic sclerosis

INTRODUCTION

Systemic sclerosis (SSc) is an autoimmune disorder that causes vasculopathy and scarring, most commonly in the lungs and skin, but it can also affect other organs. Endothelial vinculin plays a critical role in angiogenesis regulation. Therefore, vinculin overexpression in SSc may give rise to anti-vinculin antibodies, which may contribute to the development of SSc vasculopathy. The current research aims to (1) determine whether anti-vinculin autoantibodies play a significant role in the diagnosis of SSc and (2) compare anti-vinculin serum levels between two scleroderma patient populations, namely, pulmonary artery hypertension (PAH)-predominant and interstitial pulmonary fibrosis (IPF)-predominant groups.

METHODS

This research included 140 participants categorized into three groups: group I-patients with PAH-predominant; group II-patients with ILD-predominant; group III-the control group. Anti-vinculin antibodies were detected in serum samples collected from all participants using ELISA. All subjects underwent high-resolution computed tomography (CT), diffusing capacity for carbon monoxide, and pulmonary function tests.

RESULTS

Patients in group I (PAH-predominant group, N = 35) were 41.3 [± 11.4] years old, with 80% being women. Patients in group II (ILD-predominant group, N = 35) were 41.0 [± 11.5] years old. The SSc group showed significantly higher anti-vinculin antibody levels than the control group (P < 0.001). The PAH-predominant group demonstrated significantly higher anti-vinculin antibody levels and anti-vinculin positivity than the ILD-predominant group.

CONCLUSION

Anti-vinculin antibodies in the blood appear to be diagnostic biomarkers for scleroderma. Furthermore, they shed light on some novel perspectives on the pathophysiology of specific lung fibrotic changes. Key Points • This study included two groups of systemic sclerosis patients (PAH-predominant group, ILD-predominant group) as well as a control group to investigate the significance of anti-vinculin antibodies in such cases. • Our results have demonstrated that anti-vinculin antibodies can play a significant role in diagnosing and monitoring systemic sclerosis disease.

Template-Based Assembly of Proteomic Short Reads For De Novo Antibody Sequencing and Repertoire Profiling

Antibodies can target a vast molecular diversity of antigens. This is achieved by generating a complementary diversity of antibody sequences through somatic recombination and hypermutation. A full understanding of the antibody repertoire in health and disease therefore requires dedicated de novo sequencing methods. Next-generation cDNA sequencing methods have laid the foundation of our current understanding of the antibody repertoire, but these methods share one major limitation in that they target the antibody-producing B-cells, rather than the functional secreted product in bodily fluids. Mass spectrometry-based methods offer an opportunity to bridge this gap between antibody repertoire profiling and bulk serological assays, as they can access antibody sequence information straight from the secreted polypeptide products. In a step to meeting the challenge of mass spectrometry (MS)-based antibody sequencing, we present a fast and simple software tool (Stitch) to map proteomic short reads to user-defined templates with dedicated features for both monoclonal antibody sequencing and profiling of polyclonal antibody repertoires. We demonstrate the use of Stitch by fully reconstructing two monoclonal antibody sequences with >98% accuracy (including I/L assignment); sequencing a Fab from patient serum isolated by reversed-phase liquid chromatography (LC) fractionation against a high background of homologous antibody sequences; sequencing antibody light chains from the urine of multiple-myeloma patients; and profiling the IgG repertoire in sera from patients hospitalized with COVID-19. We demonstrate that Stitch assembles a comprehensive overview of the antibody sequences that are represented in the dataset and provides an important first step toward analyzing polyclonal antibodies and repertoire profiling.

Three new pyrrole alkaloids from the endophytic fungus Albifimbria viridis

Three new pyrrole alkaloids albifipyrrols A-C (1-3), were isolated from the endophytic fungus Albifimbria viridis collected from the Chinese medicinal plant. Their structures were elucidated by extensive NMR and HRESIMS spectrometric analyses. All compounds were evaluated for immunosuppressive activity. Fortunately, compound 2 exhibits certain inhibition specifically against the LPS-induced proliferation of B lymphocyte cells with IC₅₀ value 16.16 μM.

Analysis of the impact of sex and age on the variation in the prevalence of antinuclear autoantibodies in Polish population: a nationwide observational, cross-sectional study

The detection of antinuclear autoantibody (ANA) is dependent on many factors and varies between the populations. The aim of the study was first to assess the prevalence of ANA in the Polish adult population depending on age, sex and the cutoff threshold used for the results obtained. Second, we estimated the occurrence of individual types of ANA-staining patterns. We tested 1731 patient samples using commercially available IIFA using two cutoff thresholds of 1:100 and 1:160. We found ANA in 260 participants (15.0%), but the percentage of positive results strongly depended on the cutoff level. For a cutoff threshold 1:100, the positive population was 19.5% and for the 1:160 cutoff threshold, it was 11.7%. The most prevalent ANA-staining pattern was AC-2 Dense Fine speckled (50%), followed by AC-21 Reticular/AMA (14.38%) ANA more common in women (72%); 64% of ANA-positive patients were over 50 years of age. ANA prevalence in the Polish population is at a level observed in other highly developed countries and is more prevalent in women and elderly individuals. To reduce the number of positive results released, we suggest that Polish laboratories should set 1:160 as the cutoff threshold.

Pharmacological blockade of KV1.3 channel as a promising treatment in autoimmune diseases

There are more than 100 autoimmune diseases (AD), which have a high prevalence that ranges between 5% and 8% of the general population. Type I diabetes mellitus, multiple sclerosis, systemic lupus erythematosus and rheumatoid arthritis remain the health problem of highest concern among people worldwide due to its high morbidity and mortality. The development of new treatment strategies has become a research hotspot. In recent years, the study of the ion channels presents in the cells of the immune system, regarding their functional role, the consequences of mutations in their genes and the different ways of blocking them are the subject of intense research. Pharmacological blockade of KV1.3 channel inhibits Ca2+ signaling, T cell proliferation, and pro-inflammatory interleukins production in human CD4⁺ effector memory T cells. These cells mediated most of the AD and their inhibition is a promising therapeutic target. In this review, we will highlight the biological function of KV1.3 channel in T cells, consequence of the pharmacological inhibition (through anemone and scorpion toxins, synthetic peptides, nanoparticles, or monoclonal antibodies) as well as the possible therapeutical application in AD.

Importance of Autoimmune Responses in Progression of Retinal Degeneration Initiated by Gene Mutations

Inherited retinal diseases (IRDs) are clinically and genetically heterogeneous rare disorders associated with retinal dysfunction and death of retinal photoreceptor cells, leading to blindness. Among the most frequent and severe forms of those retinopathies is retinitis pigmentosa (RP) that affects 1:4,000 individuals worldwide. The genes that have been implicated in RP are associated with the proteins present in photoreceptor cells or retinal pigment epithelium (RPE). Asymmetric presentation or sudden progression in retinal disease suggests that a gene mutation alone might not be responsible for retinal degeneration. Immune responses could directly target the retina or be site effect of immunity as a bystander deterioration. Autoantibodies against retinal autoantigens have been found in RP, which led to a hypothesis that autoimmunity could be responsible for the progression of photoreceptor cell death initiated by a genetic mutation. The other contributory factor to retinal degeneration is inflammation that activates the innate immune mechanisms, such as complement. If autoimmune responses contribute to the progression of retinopathy, this could have an implication on treatment, such as gene replacement therapy. In this review, we provide a perspective on the current role of autoimmunity/immunity in RP pathophysiology.

CAR Treg: A new approach in the treatment of autoimmune diseases

Regulatory T cells (Tregs) have the role of regulating self-tolerance, and suppressing immune responses. Defects in Treg function and number can lead to in loss of tolerance or autoimmune disease. To treat or control autoimmune diseases, one of the options is to develop immune tolerance for Tregs cell therapy, which includes promotion and activation. Recently, cell-based treatment as a promising approach to increase cells function and number has been developed. Cell therapy by chimeric T antigen receptor (CAR-T) cells has shown significant efficacy in the treatment of leukemia, which has led researchers to use CAR-T cells in other diseases like autoimmune diseases. Here, we describe the existing treatments for autoimmune diseases and the available treatments based on Treg, their benefits and restrictions for implementation in clinical trials. We also discussed potential solutions to overcome these limitations. It seems novel designs of CARs to be new hope for autoimmune diseases and expected to be a potential cure option in a wide array of disease in the future. Therefore, it is very important to address this issue and increase information about it.

Tolerogenic Nanoparticles Impacting B and T Lymphocyte Responses Delay Autoimmune Arthritis in K/BxN Mice

Current treatments for unwanted antibody responses largely rely on immunosuppressive drugs compromising overall immunity. New approaches to achieve antigen-specific tolerance are desirable to avoid unwanted side effects. Several nanoparticle-based approaches that utilize different mechanisms to tolerize the B or T cell arms of the humoral immune response have shown promise for induction of antigen-specific tolerance, raising the possibility that they could work synergistically if combined. Earlier we showed that Siglec-engaging tolerance-inducing antigenic liposomes (STALs) that display both an antigen (Ag) and glycan ligands of the inhibitory co-receptor CD22 (CD22L) lead to robust antigen-specific B cell tolerance to protein antigens in naive mice. In another approach, administration of free Ag with poly(lactic-co-glycolic acid)-rapamycin nanoparticles (PLGA-R) induced robust antigen-specific tolerance through production of regulatory T cells. Here we illustrate that coadministration of STALs together with PLGA-R to naive mice induced more robust tolerance to multiple antigen challenges than either nanoparticle alone. Moreover, in K/BxN mice that develop spontaneous autoimmune arthritis to the self-antigen glucose-6-phosphate-isomerase (GPI), co-delivery of GPI-LP-CD22L and PLGA-R delayed onset of disease and in some mice prevented the disease indefinitely. The results show synergy between B cell-tolerizing STALs and T cell-tolerizing PLGA-R and the potential to induce tolerance in early stage autoimmune disease.

Bipolaquinones A-J, Immunosuppressive Meroterpenoids from a Soil-Derived Bipolaris zeicola

Ten new meroterpenoids, bipolaquinones A-J (1-10), and one known congener, isocochlioquinone F (11), were isolated and identified from the fermented rice cultures of a soil-derived fungus, Bipolaris zeicola. The planar structures of 1-10 were elucidated based on extensive spectroscopic analyses (including HRESIMS and 1D and 2D NMR data), and their absolute configurations were determined by single-crystal X-ray diffraction analyses, comparison of experimental electronic circular dichroism (ECD) data, ECD calculations, and hydrolysis reaction. The immunosuppressive activity assay revealed that compounds 2, 3, and 7-10 showed significant inhibitory activity against concanavalin A (ConA)-induced T lymphocyte proliferation with IC₅₀ values ranging from 4.1 to 9.4 μM, which furnished potential lead molecules for the design and development of new immunosuppressants for treating autoimmune-associated diseases.

The pathogenic, therapeutic and diagnostic role of exosomal microRNA in the autoimmune diseases

Exosomes are a nano-vesicle surrounded by a bilipid layer that can release from almost all cells and could be detected in tissues and biological liquids. These vesicles contain lipids, proteins, and nucleic acids (including DNA, mRNA, and miRNA) inside and on the exosomes' surface constitute their content. Exosomes can transfer their cargo into the recipient cell, which can modify recipient cells' biological activities. Recently it has been deciphering that the miRNA pattern of exosomes reveals the cellular pathophysiological situation and modifies various biological processes. Increasing data regarding exosomes highlights that the exosomes and their cargo, especially miRNAs, are implicated in the pathophysiology of various disorders, such as autoimmune disease. The current evidence on the deciphering of mechanisms in which exosomal miRNAs contributed to autoimmunity was indicated that exosomal miRNA might hold information that can reprogram the function of many of the immune cells involved in autoimmune diseases' pathogenesis. In the present study, we summarized the pathogenic role of exosomal miRNAs in several autoimmune diseases, including myasthenia gravis (MG), psoriasis, inflammatory bowel disease (IBD), type 1 diabetes (T1D), multiple sclerosis (MS), systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), Sjogren's Syndrome (SS), systemic sclerosis (SSc), vitiligo, and autoimmune thyroid diseases (AITD). Moreover, in this work, we present evidence of the potential role of exosomal miRNAs as therapeutic and diagnostic agents in autoimmune diseases.

Concomitant occurence of multiple autoantibodies against human cytochromes P450

Cytochromes P450 (CYPs) are a large superfamily of heme-containing enzymes that are essential for the metabolism of a variety of endogenous and xenobiotic compounds. The role and the possible diagnostic or prognostic value of the occurrence of anti-CYP autoantibodies (aAbs) in cancer patients are essentially unclear. Recently we reported the monitoring of aAbs against CYP4Z1 and CYP19A1 in breast cancer patients and healthy controls. In the present study, we extended this investigation by screening the sera of 47 lung cancer patients (17 female and 30 male; age range 49-84) and 119 healthy controls (60 female and 59 male; age range 21-72) for the presence of aAbs directed against CYP2D6, CYP4Z1, or CYP17A1, respectively. Determination of anti-CYP aAb levels was done using our previously established ELISA method. Most sera gave low signals while a small fraction showed stronger responses; however, there were no statistically significant differences between the different test groups. Also, there was no significant difference in aAb signals between the various subtypes of lung cancer. Unexpectedly, sera from two female lung cancer patients (age 67 (adenocarcinoma) and 70 (small cell carcinoma)) and from four healthy controls (one female and three male; age range 34-48) showed significantly elevated signals for more than one of the three CYPs tested. These findings corroborate earlier reports that anti-CYP aAbs occur with low frequency in the general population and, moreover, suggest that the simultaneous presence of multiple aAbs targeting different CYPs should be taken into consideration when evaluating anti-CYP aAbs as biomarkers.

COVID-19 and Immunological Dysregulation: Can Autoantibodies be Useful?

Coronavirus disease 2019 (COVID-19) is often associated with interstitial pneumonia. However, there is insufficient knowledge on the presence of autoimmune serological markers in patients with COVID-19. We analyzed the presence and role of autoantibodies in patients with COVID-19-associated pneumonia. We prospectively studied 33 consecutive patients with COVID-19, 31 (94%) of whom had interstitial pneumonia, and 25 age-matched and sex-matched patients with fever and/or pneumonia with etiologies other than COVID-19 as the pathological control group. All patients were tested for the presence of antinuclear antibodies (ANAs), anti-antiphospholipid antibodies, and anti-cytoplasmic neutrophil antibodies (ANCAs). Clinical, biochemical, and radiological parameters were also collected. Fifteen of 33 patients (45%) tested positive for at least one autoantibody, including 11 who tested positive for ANAs (33%), 8 who tested positive for anti-cardiolipin antibodies (immunoglobulin (Ig)G and/or IgM; 24%), and 3 who tested positive for anti-β2-glycoprotein antibodies (IgG and/or IgM; 9%). ANCA reactivity was not detected in any patient. Patients that tested positive for auto-antibodies had a significantly more severe prognosis than other patients did: 6 of 15 patients (40%) with auto-antibodies died due to COVID-19 complications during hospitalization, whereas only 1 of 18 patients (5.5%) who did not have auto-antibodies died (P = 0.03). Patients with poor prognosis (death due to COVID-19 complications) had a significantly higher respiratory rate at admission (23 breaths per minute vs. 17 breaths per minute; P = 0.03) and a higher frequency of auto-antibodies (86% vs. 27%; P = 0.008). In conclusion, auto-antibodies are frequently detected in patients with COVID-19 possibly reflecting a pathogenetic role of immune dysregulation. However, given the small number of patients, the association of auto-antibodies with an unfavorable prognosis requires further multicenter studies.

Th2 cells lacking T-bet suppress naive and memory T cell responses via IL-10

Exacerbated immune responses and loss of self-tolerance lead to the development of autoimmunity and immunopathology. Novel therapies to target autoreactive T cells are still needed. Here, we report that Th2-polarized T cells lacking the transcription factor T-bet harbor strong immunomodulatory potential and suppress antigen-specific CD8+ T cells via IL-10. Tbx21-/- Th2 cells protected mice against virus-induced type 1 diabetes development and suppressed not only naive but also memory CD8+ T cell responses. IL-10-producing, but not IL-10-deficient Tbx21-/- Th2 cells down-regulated costimulatory molecules on dendritic cells and reduced their IL-12 production after lymphocytic choriomeningitis virus infection. Impaired dendritic cell activation hindered effector and cytotoxic CD8+ T cell development after infection. These findings indicate that Tbx21-/- Th2 cells strongly suppress proinflammatory responses of naive and memory T cells via IL-10. Thus, in vivo IL-10-secreting Th2 cells could harbor a therapeutic potential for the treatment of T cell-mediated inflammatory disorders.

The role of myeloid-derived suppressor cells in rheumatoid arthritis: An update

Rheumatoid arthritis (RA) is an autoimmune disease that generally affects the joints. In the late stages of the disease, it can be associated with several complications. Although the exact etiology of RA is unknown, various studies have been performed to understand better the immunological mechanisms involved in the pathogenesis of RA. At the onset of the disease, various immune cells migrate to the joints and increase the recruitment of immune cells to the joints by several immunological mediators such as cytokines and chemokines. The function of specific immune cells in RA is well-established. The shift of immune responses to Th1 or Th17 is one of the most essential factors in the development of RA. Myeloid-derived suppressor cells (MDSCs), as a heterogeneous population of myeloid cells, play a regulatory role in the immune system that inhibits T cell activity through several mechanisms. Various studies have been performed on the function of these cells in RA, which in some cases have yielded conflicting results. Therefore, the purpose of this review article is to comprehensively understand the pro-inflammatory and anti-inflammatory functions of MDSCs in the pathogenesis of RA.

Some Common SNPs of the T-Cell Homeostasis-Related Genes Are Associated with Multiple Sclerosis, but Not with the Clinical Manifestations of the Disease, in the Polish Population

Purpose

Multiple sclerosis (MS) is an autoimmune disease, and genetic factors play an important role in its pathogenesis and progression. The aim of our study was to evaluate the frequencies of alleles and genetic variants of the T-cell homeostasis-related genes, in subjects with MS, as well as to investigate the association with MS clinical manifestations and disability.

Methods

94 subjects with MS and 160 healthy individuals have been genotyped for seven common single-nucleotide variants in IL-2RA, CTLA4, CD40, and PADI4 genes. The ages of onset, duration of the disease, and clinical condition of the MS subjects were analysed. We used the Chi² test confirmed with Fisher's exact test for statistical analysis.

Results

The frequency of allele T and CT/TT genotypes (rs7093069) in the IL2RA gene, as well as the T allele and CT/TT genotypes in rs12722598, were significantly higher in the control group. The significant differences between studied groups we also found for the G allele and GG/GA genotypes of rs3087243 in CTLA4 gene, which were more common among the control group. The heterozygous genotype TC (rs1883832) of CD40 gene was more common in the control subjects, and the frequency of the alleles and genotypes in the rs1748033 of the PADI4 gene did not differ between the studied groups. Between the studied genotypes, we did not observe any significant differences in the age of onset and duration of disease, including sex stratification.

Conclusion

Our results highlight the protective role of some of the T-cell homeostasis-related genetic variants in MS development, but not in its clinical manifestation.

Establishment of international autoantibody reference standards for the detection of autoantibodies directed against PML bodies, GW bodies, and NuMA protein

Objectives:

Reference materials are important in the standardization of autoantibody testing and only a few are freely available for many known autoantibodies. Our goal was to develop three reference materials for antibodies to PML bodies/multiple nuclear dots (MND), antibodies to GW bodies (GWB), and antibodies to the nuclear mitotic apparatus (NuMA).

Methods:

Reference materials for identifying autoantibodies to MND (MND-REF), GWB (GWB-REF), and NuMA (NuMA-REF) were obtained from three donors and validated independently by seven laboratories. The sera were characterized using indirect immunofluorescence assay (IFA) on HEp-2 cell substrates including two-color immunofluorescence using antigen-specific markers, western blot (WB), immunoprecipitation (IP), line immunoassay (LIA), addressable laser bead immunoassay (ALBIA), enzyme-linked immunosorbent assay (ELISA), and immunoprecipitation–mass spectrometry (IP-MS).

Results:

MND-REF stained 6–20 discrete nuclear dots that colocalized with PML bodies. Antibodies to Sp100 and PML were detected by LIA and antibodies to Sp100 were also detected by ELISA. GWB-REF stained discrete cytoplasmic dots in interphase cells, which were confirmed to be GWB using two-color immunofluorescence. Anti-Ge-1 antibodies were identified in GWB-REF by ALBIA, IP, and IP-MS. All reference materials produced patterns at dilutions of 1:160 or greater. NuMA-REF produced fine speckled nuclear staining in interphase cells and staining of spindle fibers and spindle poles. The presence of antibodies to NuMA was verified by IP, WB, ALBIA, and IP-MS.

Conclusions:

MND-REF, GWB-REF, and NuMA-REF are suitable reference materials for the corresponding antinuclear antibodies staining patterns and will be accessible to qualified laboratories.

IgE autoantibodies and autoreactive T cells and their role in children and adults with atopic dermatitis

The pathophysiology of atopic dermatitis (AD) is highly complex and understanding of disease endotypes may improve disease management. Immunoglobulins E (IgE) against human skin epitopes (IgE autoantibodies) are thought to play a role in disease progression and prolongation. These antibodies have been described in patients with severe and chronic AD, suggesting a progression from allergic inflammation to severe autoimmune processes against the skin. This review provides a summary of the current knowledge and gaps on IgE autoreactivity and self-reactive T cells in children and adults with AD based on a systematic search. Currently, the clinical relevance and the pathomechanism of IgE autoantibodies in AD needs to be further investigated. Additionally, it is unknown whether the presence of IgE autoantibodies in patients with AD is an epiphenomenon or a disease endotype. However, increased knowledge on the clinical relevance and the pathophysiologic role of IgE autoantibodies and self-reactive T cells in AD can have consequences for diagnosis and treatment. Responses to the current available treatments can be used for better understanding of the pathways and may shed new lights on the treatment options for patients with AD and autoreactivity against skin epitopes. To conclude, IgE autoantibodies and self-reactive T cells can contribute to the pathophysiology of AD based on the body of evidence in literature. However, many questions remain open. Future studies on autoreactivity in AD should especially focus on the clinical relevance, the contribution to the disease progression and chronicity on cellular level, the onset and therapeutic strategies.

Zika autoimmunity and Guillain-Barré syndrome

PURPOSE OF REVIEW

To summarize the recent data regarding Guillain-Barré syndrome (GBS) as an autoimmune disorder following infection with Zika virus (ZIKV) infection, including the proposed pathogenic mechanisms and the role of autoantibodies.

RECENT FINDINGS

The loss of self-tolerance that leads to autoimmune diseases is a multifactorial process that may be illustrated as 'the mosaic of autoimmunity'. Infectious agents may contribute to the development of autoimmunity by several proposed mechanisms. One of the central mechanisms is molecular mimicry, which is also the most plausible mechanism in the case of ZIKV-induced autoimmune disorders.A recent meta-analysis found a low prevalence of GBS associated with ZIKV infection. Nevertheless, the estimated cost of illness for patients with GBS associated with ZIKV are tremendous and exceed 4.7 million dollars per year in Brazil alone.

SUMMARY

Currently, there is sufficient data to indicate that ZIKV infection is one of many triggers and factors that may contribute to the development GBS. Thus, it is advised to evaluate and determine ZIKV exposure and infection in the management of potential GBS patients.

Systemic autoinflammatory diseases

Systemic autoinflammatory diseases (SAIDs) are a growing group of disorders caused by a dysregulation of the innate immune system leading to episodes of systemic inflammation. In 1997, MEFV was the first gene identified as disease causing for Familial Mediterranean Fever, the most common hereditary SAID. In most cases, autoinflammatory diseases have a strong genetic background with mutations in single genes. Since 1997 more than 30 new genes associated with autoinflammatory diseases have been identified, affecting different parts of the innate immune system. Nevertheless, for at least 40-60% of patients with phenotypes typical for SAIDs, a distinct diagnosis cannot be met, leading to undefined SAIDs (uSAIDs). However, SAIDs can also be of polygenic or multifactorial origin, with environmental influence modulating the phenotype. The implementation of a disease continuum model combining the adaptive and the innate immune system with autoinflammatory and autoimmune diseases shows the complexity of SAIDs and the importance of new methods to elucidate molecular changes and causative factors in SAIDs. Diagnosis is often based on clinical presentation and genetic testing. The timeline from onset to diagnosis takes up to 7.3 years, highlighting the indisputable need to identify new treatment and diagnostic targets. Recently, other factors are under investigation as additional contributors to the pathogenesis of SAIDs. This review gives an overview of pathogenesis and etiology of SAIDs, and summarizes recent diagnosis and treatment options.

Triggers of Inflammatory Heart Disease

Inflammatory heart disease (IHD) is a group of diseases that includes pericarditis, myocarditis, and endocarditis. Although males appear to be more commonly affected than females, IHD can be seen in any age group. While the disease can be self-limiting leading to full recovery, affected individuals can develop chronic disease, suggesting that identification of primary triggers is critical for successful therapies. Adding to this complexity, however, is the fact that IHD can be triggered by a variety of infectious and non-infectious causes that can also occur as secondary events to primary insults. In this review, we discuss the immunological insights into the development of IHD as well as a mechanistic understanding of the disease process in animal models.

Immunosuppressive Nor-isopimarane Diterpenes from Cultures of the Fungicolous Fungus Xylaria longipes HFG1018

Eighteen new nor-isopimarane diterpenes, xylarinorditerpenes A-R (1-18), along with two previously reported compounds, 14α,16-epoxy-18-norisopimar-7-en-4α-ol (19) and the labdane-type diterpene agatadiol (20), were isolated from cultures of the fungicolous fungus Xylaria longipes HFG1018 isolated from the wood-rotting basidiomycete Fomitopsis betulinus. The structure elucidation and relative configuration assignments of 1-18 were accomplished by interpretation of spectroscopic data and through computational methods. The absolute configurations of 1, 4, and 16 were determined by single-crystal X-ray diffraction. Compounds 1-16 possess an 18- or 19-nor-isopimarane skeleton, and compounds 17 and 18 possess an 18,19-dinor-isopimarane skeleton. Compounds 2-5, 9, 14, 19, and 20 showed immunosuppressive activity but were devoid of cytotoxicity against the cell proliferation by concanavalin A-induced T lymphocytes and lipopolysaccharide-induced B lymphocytes, with IC₅₀ values varying from 1.0 to 27.2 μM and from 16.1 to 51.8 μM, respectively.