Serum Autoantibodies Research Articles

The IL-21-TET2-AIM2-c-MAF pathway drives the T follicular helper cell response in lupus-like disease.

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease that involves T follicular helper (TFH) cell‐mediated humoral immune responses. Absent in melanoma 2 (human AIM2 and murine Aim2) is a well‐known component of the inflammasome in the innate immune system. Surprisingly, we observed that in SLE patients, upregulated levels of AIM2 expression were found in peripheral blood and skin lesions, with the highest levels detected in TFH‐like cells. In the CD4creAim2fl/fl conditional knockout mice, a markedly reduced TFH cell response was observed, with significantly lower levels of serum autoantibodies and proteinuria, as well as profoundly reduced renal IgG deposition in pristane‐induced lupus mice. Mechanistically, IL‐21 was found to recruit hydroxymethyltransferase ten‐eleven translocation 2 (TET2) to the AIM2 promoter, resulting in DNA demethylation and increased transcription of AIM2. In addition, AIM2 could regulate c‐MAF expression to enhance IL‐21 production, which consequently promoted TFH cell differentiation. Our results have identified a role of AIM2 in promoting the TFH cell response and further revealed that the IL‐21‐TET2‐AIM2‐c‐MAF signalling pathway is dysregulated in lupus pathogenesis, which provides a potential therapeutic target for SLE.

Preclinical stage abundance and nuclear antigen reactivity of faecal Immunoglobulin A vary among males and females of lupus-prone mouse models.

Systemic lupus erythematosus (SLE) is characterized by the production of pathogenic autoantibodies with nuclear antigen (nAg) specificity. Using (SWRxNZB)F1 (SNF1) mice, we showed higher levels of Immunoglobulin A (IgA) production in the intestine and the nAg reactivity of faecal IgA under lupus susceptibility. Here, we determined whether the faecal IgA abundance and nAg reactivity are higher in, different among, various lupus-prone preclinical models (MRL/lpr, NZBxNZW-F1, SNF1, NZM2410 and NZM2328). We also determined whether the faecal IgA nAg reactivity at preseropositive ages correlates with the eventual serum autoantibody levels in males and females of these mouse models. We show that age-dependent increase in the abundance and nAg reactivity of faecal IgA can vary among different lupus-prone mouse models. Importantly, faecal IgA in these mice show significant levels of nAg reactivity, starting as early as at juvenile age. Furthermore, the pre-seropositive stage nAg reactivity of faecal IgA in most lupus-prone strains correlates well with that of eventual, seropositive stage systemic autoantibody levels. Gender differences in serum autoantibody levels were preceded by similar differences in the faecal IgA abundance and nAg reactivity. These observations suggest that faecal IgA features, nAg reactivity particularly, could serve as a biomarker for early prediction of the eventual systemic autoimmunity in lupus-prone subjects.

Abstract 42: B-Lymphocyte subset distribution in patients with hyperprolactinemia

Background: The PRL-R is a member of the GH/cytokine receptor super family which is also expressed on immune cells and activation modulates several cell functions such as differentiation, proliferation, survival, and secretion. Peripheral B-cell subset distribution and the serum autoantibody profile in women with HPRL are largely unknown.Aims and Objectives: The current study aimed to investigate B-lymphocyte subset distribution and the autoantibody prevalence in women with HPRL.Methods: Peripheral blood was collected from 30 women who had PRL>50ng/ml and from 24 healthy women who had normal PRL aged between 18-45. All were examined for prolactin, B-cell subsets were measured by flow cytometry, Anti-nuclear antibody (ANA), Rheumatoid factor, Anticardiolipin IgG, Immunoglobulin G, M&A, Anti-TPO, Anti-Tg.Results: The percentages of Plasmablast (p-0.015) among the total B cells from and Immunoglobulin IgA (p-0.012) in HPRL women were significantly higher than those from healthy women, while percentages of B-regulatory (p-0.003) and Mature cell (p<0.001) and Immunoglobulin M (p-0.012) were higher in healthy women.Conclusions: Women with HPRL had a higher prevalence of more Plasmablast cells and lower prevalence of B-regulatory cells than healthy women.

B-cell activating factor and IL-21 levels predict treatment response in autoimmune hepatitis

Background & AimsIncreased serum IgG and autoantibodies suggest involvement of B cells in autoimmune hepatitis (AIH). The aim of this study was to assess levels of B cell activating factor of the tumour necrosis family (BAFF), IL-21, and circulating B cell populations in AIH and correlate these to treatment response.MethodsBAFF and IL-21 levels were determined in 66 patients with AIH before treatment and 10 healthy controls. Flow cytometry was performed on circulating B cells of 10 patients with AIH and 12 healthy controls.ResultsBased on BAFF and IL-21 levels, untreated patients with AIH were divided into 3 groups: 27 (41%) patients with normal BAFF and IL-21 (normal BAFF), 27 (41%) patients with elevated BAFF but normal IL-21 (high BAFF), and 12 (18%) patients with elevated IL-21 (high IL-21). The high BAFF group presented with higher bilirubin compared with the normal BAFF and high IL-21 groups (159 vs. 26 vs. 89 μmol/L; p = 0.001; Mann–Whitney U test). After 12 months of treatment, 54% of the high BAFF group reached remission compared with 34% of the normal BAFF group and 0% of the high IL-21 group (p = 0.006, Chi-square test). During follow-up, 3 patients (25%) with high IL-21 developed primary sclerosing cholangitis (PSC) variant syndrome. Autoimmune-associated B cells were increased in patients with AIH compared with healthy controls (4.4 vs. 1.4%; p = 0.003, Mann–Whitney U test). BAFF levels were correlated positively with naïve B cells (p = 0.01) and negatively with class-switched B cells (p = 0.003) and nonclass-switched B cells (p = 0.005, Spearman correlation).DiscussionUsing BAFF and IL-21, we identified different immunological phenotypes of AIH with a different presentation, treatment response, and outcome. Patients with high IL-21 had the poorest treatment response and a risk of developing PSC variant syndrome. BAFF level was related to shifts in circulating B-cell populations.Lay summaryIn patients with untreated autoimmune hepatitis (AIH), circulating B-cell activating factor of the tumour necrosis family (BAFF), IL-21, and B-cell populations were determined. Three subgroups were identified: with (1) normal BAFF and IL-21, (2) elevated BAFF and normal IL-21, and (3) elevated IL-21. Remission after 1-year treatment occurred in 54, 34, and 0% in Groups 1, 2, and 3, respectively. Group 2 had higher bilirubin, indicating more liver dysfunction. In 25% of patients with high IL-21, AIH-PSC variant syndrome developed, but none in the other groups. Autoimmune-associated B cells were elevated and BAFF levels correlated with certain B cells.

Host Genetics But Not Commensal Microbiota Determines the Initial Development of Systemic Autoimmune Disease in BXD2 Mice.

To determine the extent to which the gut microbiome influences systemic autoimmunity in a mouse model of lupus. We generated germ-free (GF) lupus-prone BXD2 mice, which under normal conditions develop spontaneous germinal centers (GCs) and high titers of serum autoantibodies. GF status was confirmed by gut bacterial culture. The autoimmune phenotypes of 6- and 12-month-old gnotobiotic GF BXD2 mice and specific pathogen-free (SPF) BXD2 mice were compared. Serum levels of autoantibodies were measured by enzyme-linked immunosorbent assay. Histologic sections of the mouse kidney and joints were evaluated. Flow cytometry was used to analyze GCs and age-associated B cells. CD4+ T cells were analyzed for PD-1+ICOS+ activated T cells, T follicular regulatory (Tfr) cells (Foxp3+CD25+ PD-1+CXCR5+), and PD-1+ICOS+ T cells expressing interleukin-17A (IL-17A) or interferon-γ (IFNγ) after stimulation with phorbol myristate acetate (PMA)/ionomycin. In 6-month-old mice, GF status did not affect splenomegaly, GC B cells, age-associated B cells, or serum autoantibody levels, except for IgG antihistone. GF BXD2 mice exhibited a significantly higher percentage of Tfr cells compared to their SPF counterparts (P < 0.05). At 12 months of age, however, GF BXD2 mice had significantly diminished IgG autoantibody levels and a lower percentage of GC B cells and age-associated B cells (P < 0.05). Following stimulation with PMA/ionomycin, PD-1+ICOS+ CD4+ T cells expressed significantly lower IL-17A, but not IFNγ, levels in GF BXD2 mice compared to SPF BXD2 mice (P < 0.01). SPF BXD2 mice and GF BXD2 mice developed equivalent renal and joint disease with no significant differences in severity. Our results suggest a model in which genetics plays a dominant role in determining the initial development of autoimmunity. In contrast, gut microbiomes may regulate the persistence of certain aspects of systemic autoimmunity.

Routine IgG4 staining in minor salivary gland biopsy in a cohort of Italian Caucasian patients suffering from xerostomia.

ObjectivesIgG4-related disease is a potentially systemic disease mimicking and overlapping with different autoimmune diseases, such as primary Sjögren’s syndrome (pSS). The involvement of salivary glands, previously called Mikulicz’s disease, has been reclassified as IgG4-related sialadenitis (SA). The aim of this study was to assess the prevalence of IgG4-SA in a cohort of Italian Caucasian patients presenting with xerostomia and to evaluate the eventual overlap between IgG4-SA and pSS.Material and methodsWe included 154 patients – 15 males and 139 females, mean age 54.18 ±14.24 years, who underwent minor salivary gland biopsy between March and December 2019 for xerostomia. Histopathology was evaluated using Chisholm-Mason (CM) and focus score (FS) for pSS and immunohistochemical study with IgG4 staining for IgG4-SA were performed. Serum autoantibodies (anti-SSa/RoAb, anti-SSB/LaAb, antinuclear antibodies, rheumatoid factor) were also assessed.ResultsIn 69 patients (44.8%) FS 0 was found, while FS ≥ 1 was presented in 85 (55.2%). Chisholm-Mason score < 3 and CM ≥ 3 was found in 73 (47.4%) and 81 (52.6%) cases, respectively. IgG4/high-power field level was 20 in 3 pSS patients (1.9%), but none of them had an IgG4/IgG ratio ≥ 40, as well as tissue fibrosis with storiform pattern, obliterative vasculitis, and tissue eosinophilia. The diagnosis of pSS, was confirmed in 92 patients (59.74%). No patient was definitively diagnosed with an IgG4-related disease.ConclusionsIn the case of xerostomia, the evaluation of the histopathological specimen for IgG4 should not be routinely performed, at least in an Italian-based Caucasian population. Moreover, immunohistochemistry should not be requested in the case of a negative result of biopsy for pSS.

Inpatient Management of Encephalopathy.

Unexplained encephalopathy is a common occurrence in tertiary care centers and neurologic disorders should be considered after ruling out the infectious, toxic and metabolic etiologies. Neuroimaging combined with a thorough history and examination is often helpful in ruling out stroke and fulminant demyelinating encephalopathies. Autoimmune encephalopathy should be suspected in any patient with unexplained acute or subacute onset encephalopathy or rapidly progressing dementia. Anti-N-methyl-D-aspartate receptor (NMDA-R) encephalitis is the most studied form and Hashimoto encephalitis is the most controversial form of autoimmune encephalopathies. Obtaining a combined serum and Cerebrospinal fluid (CSF) autoantibody testing will increase the diagnostic yield of autoimmune and paraneoplastic encephalitis. When diagnosing NMDA receptor antibodies CSF is always more sensitive than serum and in contrast, voltage-gated potassium channel (VGKC) complex antibodies are more readily detectable in serum than in CSF. Neural-specific antibody tests frequently result after several weeks and treatment should be administered without a significant delay to prevent brain damage. Autoimmune encephalitis is often treatment responsive when immunotherapy (glucocorticoids, intravenous immune globulin, plasma exchange) is used in various combinations. The absence of inflammatory markers and autoantibodies in the serum or CSF may not rule out the possibility of paraneoplastic encephalopathies.

Epitopes specificity of antibodies to thyroid peroxidase in patients with Graves’ disease, Hashimoto’s thyroiditis and overlap-syndrome

BackgroundAntibodies against thyroid peroxidase (anti-TPO) serve as clinical markers of thyroid autoimmune diseases (TAIDs). By trying to elucidate the causes of heterogeneity in autoantibody levels among patients with different TAIDs it becomes possible to clarify the pathophysiology of GD and HT. ObjectiveTo investigate the heterogeneity of epitopes recognized by anti-TPO in patients with Hashimoto’s thyroiditis (HT), Graves’ disease (GD) and overlap-syndrome. MethodsWe carried out a cross-sectional study on 398 patients with GD, HT and overlap syndrome and analyzed the specificity of epitopes and binding constants of TPO with monoclonal antibodies (MAbs). Ten MAbs to TPO were used, of which five were reactive with native TPO and the rest were reactive with denaturated TPO. ResultsThe autoantibodies in blood serum of HT patients inhibited the binding of MAb63 more significantly than those in serum of GD patients: 59.62 % versus 54.02 %, respectively (p = 0.001). The anti-TPOs in serum of GD patients inhibited the binding of MAb77 more significantly than those in serum of HT patients: 54.36 % versus 51.13 %, respectively (p = 0.047). The binding of MAb45 was more inhibited in serum of patients with anti-TPO concentration over 1000 IU/ml (58.36 %). The blood serum of patients with overlap-syndrome showed less significant inhibition of MAb63 binding than that of patients with no overlap-syndrome: 52.47 % versus 58.81 %, respectively (p = 0.043). ConclusionMapping the epitopes to TPO with the help of MAbs may improve the differential diagnosis between different thyroid autoimmunities.

Identification and validation of serum autoantibodies in children with B-cell acute lymphoblastic leukemia by serological proteome analysis

BackgroundB-cell acute lymphoblastic leukemia (B-ALL) is the most common malignancy of childhood. Even though significant progresses have been made in the treatment of B-ALL, some pediatric B-ALL have still poor prognosis. The identification of tumor autoantibodies may have utility in early cancer diagnosis and immunotherapy. In this study, we used serological proteome analysis (SERPA) to screen serum autoantibodies of pediatric B-ALL, aiming to contribute to the early detection of B-ALL in children.MethodsThe total proteins from three pooled B-ALL cell lines (NALM-6, REH and BALL-1 cells) were separated using two-dimensional gel electrophoresis (2-DE), which was followed by Western blot by mixed serum samples from children with B-ALL (n=20) or healthy controls (n=20). We analyzed the images of 2-D gel and Western blot by PDQuest software, and then identified the spots of immune responses in B-ALL samples compared with those in control samples. The proteins from spots were identified using mass spectrometry (MS). The autoantibodies against alpha-enolase (α-enolase) and voltage-dependent anion-selective channel protein 1 (VDAC1) were further validated in sera from another 30 children with B-ALL and 25 normal individuals by the use of enzyme-linked immunosorbent assay (ELISA). The protein expression levels of the candidate antigens α-enolase and VDAC1 in B-ALL were thoroughly studied by immunohistochemical analysis.ResultsUtilizing the SERPA approach, α-enolase and VDAC1 were identified as candidate autoantigens in children with B-ALL. The frequencies of autoantibodies against α-enolase and VDAC1 in children with B-ALL were 27% and 23% by using ELISA analysis, respectively, which were significantly higher than those in normal controls (4% and 0, p<0.05). Immunohistochemical analysis showed the expression of α-enolase and VDAC1 was positive in 95% and 85% of B-ALL patients, respectively, but negative expression levels were showed in the control group.ConclusionsThis study incidated that α-enolase and VDAC1 may be the autoantigens associated with B-ALL. Therefore, α-enolase and VDAC1 autoantibodies may be the potential serological markers for children with B-ALL.

Serum complements and immunoglobulin profiles in systemic lupus erythematosus patients: An observational study at a teaching hospital

Context:Serum complement proteins and autoantibodies play an important role in the pathogenesis and diagnosis of systemic lupus erythematosus (SLE). Abnormalities in various immunoglobulin levels are described in patients of SLE.Aims:To study the spectrum of clinical manifestations and measure the serum levels of complement C3, complement C4, autoantibodies and immunoglobulin G (IgG) in patients of SLE and compare with healthy controls.Settings and Design:The present study is a prospective hospital-based observational study conducted between May 2014 and December 2018.Statistical Analysis Used:Unpaired t-test was used to compare the mean values between the SLE patients and healthy controls.Material and Methods:A total of 100 cases of SLE and 100 healthy controls were included in the study. The clinical data were retrieved. Serum antinuclear antibody, anti-ds DNA antibody, and anti-Smith antibody levels, and complements C3, C4 and IgG were measured.Results:Arthritis (89%) and anaemia (65%) were two common clinical presentations. The low complement C3 levels and C4 were detected in 64 and 62% of the SLE patients. Serum IgG was increased in 41% of the patients. A reduced level of IgG was detected in 6% of the patients.Conclusion:Primary care physicians should be aware of the clinical and serological manifestations of SLE as early detection will reduce end-organ damage. Autoantibody testing and complement testing should be done in all suspected cases. This study showed a significantly reduced C3 and C4 and elevated IgG in many cases of SLE as compared to control. Hypogammaglobulinemia was also present in a minority of the cases.

Disease mechanisms in Sjögren's syndrome: What do we know?

Why should we explore and study disease mechanisms? This is particularly important when we are dealing with complex pathogenesis without a direct causal agent, for example, syndromes with multiple organ involvements. Sjögren's syndrome is definitely such an entity. Also, there are a number of reasons for such studies such as disclosing the aetiology, to identify biomarkers for diagnosis and assessment of the disease process and monitor response to treatment, to determine targets for treatment, to define critical items in classification criteria, amongst others. Samples available for the study of disease mechanisms in Sjögren's syndrome have included serum (autoantibodies, cytokines), DNA (gene profiling, GWAS), cells (phenotypes/flow cytometry, proportion of cells/CyTOF), tissue (focal inflammation, germinal centres, mass cytometry), and saliva (proteomics, biochemistry, mucosal immunity). An original explanatory concept for the pathogenesis of Sjögren's syndrome proposed a specific and self-perpetuating immune-mediated loss of exocrine tissue as the principal cause of glandular hypofunction. This hypothesis however falls short of accommodating several Sjögren's syndrome-related phenomena and experimental findings. Today, the emergence of advanced bio-analytical platforms has further enabled the identification of central pathogenic processes and potential biomarkers. The purpose of this minor review is to highlight a selection of previous but also recent and novel aspects on the disease mechanisms in Sjögren's syndrome.

A combination of multiple autoantibodies is associated with the risk of Alzheimer\u2019s disease and cognitive impairment

Autoantibodies are self-antigen reactive antibodies that play diverse roles in the normal immune system, tissue homeostasis, and autoimmune and neurodegenerative diseases. Anti-neuronal autoantibodies have been detected in neurodegenerative disease serum, with unclear significance. To identify diagnostic biomarkers of Alzheimer’s disease (AD), we analyzed serum autoantibody profiles of the HuProt proteome microarray using the discovery set of cognitively normal control (NC, n = 5) and AD (n = 5) subjects. Approximately 1.5-fold higher numbers of autoantibodies were detected in the AD group (98.0 ± 39.9/person) than the NC group (66.0 ± 39.6/person). Of the autoantigen candidates detected in the HuProt microarray, five autoantigens were finally selected for the ELISA-based validation experiment using the validation set including age- and gender-matched normal (NC, n = 44), mild cognitive impairment (MCI, n = 44) and AD (n = 44) subjects. The serum levels of four autoantibodies including anti-ATCAY, HIST1H3F, NME7 and PAIP2 IgG were significantly different among NC, MCI and/or AD groups. Specifically, the anti-ATCAY autoantibody level was significantly higher in the AD (p = 0.003) and MCI (p = 0.015) groups compared to the NC group. The anti-ATCAY autoantibody level was also significantly correlated with neuropsychological scores of MMSE (rs = − 0.229, p = 0.012), K-MoCA (rs = − 0.270, p = 0.003), and CDR scores (rs = 0.218, p = 0.016). In addition, a single or combined occurrence frequency of anti-ATCAY and anti-PAIP2 autoantibodies was significantly associated with the risk of MCI and AD. This study indicates that anti-ATCAY and anti-PAIP2 autoantibodies could be a potential diagnostic biomarker of AD.

Analysis of clinical features and prognosis of acute severe autoimmune hepatitis

Objective: To analyze the clinical features and prognosis of acute severe autoimmune hepatitis (AIH). Methods: A retrospective analysis of the clinical data of patients with acute severe AIH admitted to our hospital from 2008 to 2019 was divided into acute AIH (A-AIH) and chronic acute AIH (AC-AIH) according to the presence or absence of liver diseases. Patients' general condition, liver biochemistry, immunology, histological features of liver, hormonal therapies prognosis and related factors were analyzed. Results: A total of 41 cases [39 females, age (54.24 ± 10.55) years] were collected. Alanine aminotransferase (ALT) and total bilirubin (TBil) were significantly increased, and the international normalized ratio (INR) was > 1.5. Acute lobular inflammation was the feature of acute and severe AIH in the histology of liver. The serum IgG level was (28.36 ± 8.35) g / L. The positive rate of antinuclear antibody (ANA) and anti-smooth muscle antibody (ASMA) was 82.9%, and 17.1%, respectively. Over 70% of acute severe AIHs were AC-AIH. The duration of onset of AC-AIH was > 8 weeks, while most A-AIHs < 8 weeks, and the differences between the two groups were statistically significant (P = 0.001). The mortality rate within 30 days after hormonal treatment was 19.5%. There were statistically significant differences in TBil, Model for End-Stage Liver Disease (MELD) score and leukocyte count between the death and survival group. Conclusion: The mortality rate in acute severe AIH is high, and most of them have the basis of chronic liver disease. Serum IgG level, autoantibodies and acute lobular inflammation are important factors for diagnosis. The prognosis of hormonal therapy is related to the patients' condition and course of disease.

Chinese medicine in the treatment of autoimmune hepatitis: Progress and future opportunities.

Autoimmune hepatitis (AIH) is a chronic inflammatory liver disease occurring in individuals of all ages with a higher incidence in females and characterized by hypergammaglobulinemia, elevated serum autoantibodies and histological features of interface hepatitis. AIH pathogenesis remains obscure and still needs in‐depth study, which is likely associated with genetic susceptibility and the loss of immune homeostasis. Steroids alone and in combination with other immunosuppressant agents are the primary choices of AIH treatment in the clinic, whereas, in some cases, severe adverse effects and disease relapse may occur. Chinese medicine used for the treatment of AIH has proven its merits over many years and is well tolerated. To better understand the pathogenesis of AIH and to evaluate the efficacy of novel therapies, several animal models have been generated to recapitulate the immune microenvironment of patients with AIH. In the current review, we summarize recent advances in the study of animal models for AIH and their application in pharmacological research of Chinese medicine‐based therapies and also discuss current limitations. This review aims to provide novel insights into the discovery of Chinese medicine‐originated therapies for AIH using cutting‐edge animal models.

P53 Gene Mutation Associated With Worse Clinicopathological Characteristic in Breast Cancer

Background: P53 is a tumour suppresor gene. In breast cancer, p53 gene mutation were noted with frequency of about 30% (range 15 to 71%) and associated with poor prognosis. This study was performed to determine p53 mutation association with clinicopathological characteristic in breast cancer and to assess the suitability of patients’ serum to detect p53 autoantibody. Methods: This study conducted in Hospital Seberang Jaya and Institut Perubatan dan Pergigian Termaju, Universiti Sains Malaysia. Sixty-four breast cancer patients with available fresh breast cancer tissue that been kept under -80°C and with complete clinicopathological, data involve in this study. These fresh breast tissues DNA extracted and 10sampels sent for DNA sequencing. The remaining 54samples proceeded with Polymerase Chains Reaction analysis based on the result from DNA sequencing. The serum of these patients was also taken for p53 autoantibody study using ELISA method. Results: The mean age of the patients in this study was 52.45±9.51 yrs. Most of the patients were Malay with 67.2% followed by Indian and Chinese with 17.2% and 15.6% respectively. 51.6%, of these patients undergone CT scan staging and 14.1% has distant metastases. p53 gene mutation prevalence showed rs1042522 only has 15.7% mutation. There was 54.7% Deletion A and 45.3% Wild Type A detected in rs59758982, 87.5% Deletion A and 12.5% Wild Type A in rs35069695 and 92.2 % recorded for Deletion GAA in rs376546152. There was no significant result between these mutation with breast cancer molecular classification and breast cancer aggressiveness except for rs59758982 shows significant result with p value 0.04 (p &lt;0.05). In regards on for p53 serum autoantibodies, 20.3% of the patients noted to be positive but it has no significant association with p53 gene mutations. Conclusion: In this study, tissue p53 genetic mutation has no significant association with clinicopathological characteristic of breast cancer and the use of serum p53 autoantibody as biomarkers is inconclusive.

The Conundrum of Psoriatic Arthritis: a Pathogenetic and Clinical Pattern at the Midpoint of Autoinflammation and Autoimmunity.

Psoriatic arthritis (PsA) is a chronic inflammatory condition characterized by psoriasis, synovitis, enthesitis, spondylitis, and the possible association with other extra-articular manifestations and comorbidities. It is a multifaceted and systemic disorder sustained by complex pathogenesis, combining aspects of autoinflammation and autoimmunity. Features of PsA autoinflammation include the role of biomechanical stress in the onset and/or exacerbation of the disease; the evidence of involvement of the innate immune response mediators in the skin, peripheral blood and synovial tissue; an equal gender distribution; the clinical course which may encounter periods of prolonged remission and overlapping features with autoinflammatory syndromes. Conversely, the role of autoimmunity is evoked by the association with class I major histocompatibility complex alleles, the polyarticular pattern of the disease which sometimes resembles rheumatoid arthritis and the presence of serum autoantibodies. Genetics also provide important insights into the pathogenesis of PsA, particularly related to class I HLA being associated with psoriasis and PsA. In this review, we provide a comprehensive review of the pathogenesis, genetics and clinical features of PsA that endorse the mixed nature of a disorder at the crossroads of autoinflammation and autoimmunity.

Autoantibodies against desmoglein 2 are not pathogenic in pemphigus

BackgroundAnti-desmoglein 1 and 3 autoantibodies justify acantholysis in pemphigus; however, the pathogenesis of anti-desmoglein 2 is hypothetical. ObjectiveTo compare the participation of desmogleins 1, 2 and 3 through the production of serum autoantibodies, and protein and gene expression in the skin/mucosa of patients with pemphigus foliaceus and pemphigus vulgaris. MethodsThe autoantibodies were titrated by ELISA in 202 samples of pemphigus foliaceus, 131 pemphigus vulgaris, 50 and 57 relatives of patients with pemphigus foliaceus and pemphigus vulgaris, respectively, and 114 controls. Protein and gene expressions were determined by immunohistochemistry and qPCR in the skin/mucosa of 3 patients with pemphigus foliaceus and 3 patients with pemphigus vulgaris. ResultsHigher titers of anti-desmoglein 2 (optical density) resulted in pemphigus foliaceus and pemphigus vulgaris, when compared to controls (0.166; 0.180; 0.102; respectively; p < 0.0001). There was a correlation between anti-desmoglein 2 and anti-desmoglein 1 titers in pemphigus foliaceus (r = 0.1680; p = 0.0206). There was no cross-reaction of anti-desmoglein 2 with desmoglein 1 and 3. Protein overexpression of desmoglein 2 was observed in intact and lesional skin of patients with pemphigus compared to the skin of controls. Internalization granules of desmoglein 1 and 3, but not of desmoglein 2, were observed in lesions of pemphigus foliaceus and pemphigus vulgaris, respectively. Gene overexpression of desmoglein 2 was observed in the mucosa. Study limitationsSmall sample size for the statistical analysis of protein and gene expression. ConclusionAutoantibodies against desmoglein 2 are not pathogenic in pemphigus; protein and gene overexpression of desmoglein 2 in the skin and mucosa may be involved in acantholysis repair.

Transforming mutations in the development of pathogenic B cell clones and autoantibodies.

Autoimmune diseases are characterized by serum autoantibodies, some of which are pathogenic, causing severe manifestations and organ injury. However, autoantibodies of the same antigenic reactivity are also present in the serum of asymptomatic people years before they develop any clinical signs of autoimmunity. Autoantibodies can arise during multiple stages of B cell development, and various genetic and environmental factors drive their production. However, what drives the development of pathogenic autoantibodies is poorly understood. Advances in single-cell technology have enabled the deep analysis of rare B cell clones producing pathogenic autoantibodies responsible for vasculitis in patients with primary Sjögren's syndrome complicated by mixed cryoglobulinaemia. These findings demonstrated a cascade of genetic events involving stereotypic immunoglobulin V(D)J recombination and transforming somatic mutations in lymphoma genes and V(D)J regions that disrupted antibody quality control mechanisms and decreased autoantibody solubility. Most studies consider V(D)J mutations that enhance autoantibody affinity to drive pathology; however, V(D)J mutations that increase autoantibody propensity to form insoluble complexes could be a major contributor to autoantibody pathogenicity. Defining the molecular characteristics of pathogenic autoantibodies and failed tolerance checkpoints driving their formation will improve prognostication, enabling early treatment to prevent escalating organ damage and B cell malignancy.

Association of autoantibodies to muscarinic acetylcholine receptors with gastrointestinal symptoms and disease severity in patients with postural orthostatic tachycardia syndrome.

Previous studies have reported a relationship between postural orthostatic tachycardia syndrome (POTS) and positivity for serum autoantibodies against G-protein-coupled receptors (GPCRs). However, the role of these autoantibodies in POTS is unclear. The present retrospective study analyzed the autoimmune etiology of POTS in 24 patients using a head-up tilt test to assess for any correlation between the clinical features of POTS and serum levels of autoantibodies against diverse GPCRs. In total, ten assessment items, including autonomic function tests, were analyzed. Of these, persistent, gastrointestinal symptoms and disease severity showed a significant association with the serum level of anti-muscarinic acetylcholine receptor (mAChRs) antibodies (gastrointestinal symptoms, M1, M2, M5; disease severity, M1, M3, M4, M5) [P <0.05]), while no significant association was found between the clinical features and autoantibodies against adrenergic receptors (α1, α2, β1, β2), angiotensin receptor 1, or endothelin receptor A. The patients were further divided into two groups based on the presence or absence of persistent gastrointestinal symptoms and then were characterized by the ten assessment items and neuropsychological tests, including the Wechsler Adult Intelligence Scale score and Self-Rating Depression Scale score. The results demonstrated a clear difference between the two groups in terms of disease severity, age at onset (older or younger than 20 years), and processing speed index (P <0.05), which were highly consistent with the association between these clinical features and the levels of serum anti-mAChR antibodies, particularly the anti-M5 receptor antibody. These findings suggested that anti-mAChR antibodies may play an important role in a subgroup of POTS patients with persistent gastrointestinal symptoms.

Identification and Validation of Novel Serum Autoantibodies Biomarkers for Staging Liver Fibrosis in Patients With Chronic Hepatitis B

Aim: Liver fibrosis monitoring is essential in patients with chronic hepatitis B (CHB). However, less robust, noninvasive diagnostic methods for staging liver fibrosis, other than liver biopsy, are available. Our previous study demonstrated a panel of cellular proteins recognized by autoantibodies that may have potential value in discrimination of CHB and liver cirrhosis. We aim to assess the diagnostic value of these serum autoantibodies for staging liver fibrosis.Methods: Candidate autoantigens were screened and assessed by microarray analysis in 96 healthy controls and 227 CHB patients with pre-treatment biopsy-proven METAVIR fibrosis score, comprising 69, 115, and 43 cases with S0-1, S2-3, and S4 stages, respectively. Autoantibodies with potential diagnostic value for staging liver fibrosis were verified by enzyme-linked immunosorbent assays (ELISA). Receiver operating characteristic curve was conducted to evaluate autoantibody performance.Results: Microarray analysis identified autoantigens CENPF, ACY1, HSPA6, and ENO1 with potential diagnostic value for liver fibrosis staging, among which CENPF and ACY1 were validated using ELISA. CENPF and ACY1 autoantibodies had area under the curve values of 0.746 and 0.685, 58.14 and 74.42% sensitivity, and 88.41 and 60.87% specificity, respectively, for discriminating liver fibrosis stages S4 and S0-1. The prevalence of CENPF and ACY1 autoantibodies was not correlated with age, sex or level of inflammation.Conclusions: Autoimmune responses may be elicited during progression of liver fibrosis, and serum autoantibodies may be a valuable biomarker for staging liver fibrosis deserving of further study.