Elevated Autoantibodies Research Articles

Direct correlation between plasma microbial translocation and autoantibodies in first-degree relatives of patients with systemic lupus erythematosus

Abstract Background The process of events underlying autoantibody production in systemic lupus erythematosus (SLE) is unknown. Methods Plasma from 36 female African-Americans (18 unrelated healthy controls (UHCs) and 18 first-degree relatives of SLE patients (FDRs)) were assessed for autoantibodies by autoantibody array, lipopolysaccharide (LPS) levels by the limulus amebocyte assay and microbiome by 16S rDNA analysis. Results Compared to UHCs, FDRs exhibited elevated plasma autoantibody levels but not similar total IgGs. The median plasma IgGs were 346 (interquartile range, 236–465) and 480 (286–891) for anti-double strand DNA (anti-dsDNA, P = 0.04, Mann-Whitney U-test), 3422 (2863–4076) and 4815 (3447–8464) for anti-single strand DNA (anti-ssDNA, P = 0.03), and 4593 (4050–5521) and 4714 (4004–5278) for total IgGs (P = 0.95), in UHCs and FDRs respectively. Furthermore, parent/child of patients exhibited elevated plasma LPS compared to UHCs. Plasma LPS levels were 59.1 (53.3–68.6) and 71.2 (62.2–80.4) for UHCs and parent/child of patients respectively (P = 0.03). Notably, plasma LPS was positively correlated with IgG anti-dsDNA (r = 0.53, P = 0.02, Spearman correlation) and anti-ssDNA (r = 0.53, P = 0.02) in FDRs but not in UHCs (P > 0.70). Plasma microbiome revealed a reduced diversity (P < 0.02) and lower abundance of Streptococcaceae (unadjusted P = 0.01, adjusted for multiple comparisons P = 0.10) in FDRs compared to UHCs. The ratios of Firmicutes to Bacteroidetes were 6.75 (0.66–42.5) in UHCs and 3.37 (0.63–22.5) in FDRs but did not achieve significance. Conclusion Taken together, these results indicate a possible role for plasma microbial translocation and microbiome composition in autoantibody development in SLE.

Familial Association of Granulocyte-Macrophage Colony-Stimulating Factor Autoantibodies in Inflammatory Bowel Disease.

Elevated granulocyte-macrophage colony-stimulating factor auto-antibodies (GM-CSF Ab) are associated with increased intestinal permeability and stricturing behavior in Crohn disease (CD). We tested for familial association of serum GM-CSF Ab level in CD and ulcerative colitis (UC) families. Serum GM-CSF Ab concentration was determined in 230 pediatric CD probands and 404 of their unaffected parents and siblings, and 45 UC probands and 71 of their unaffected parents and siblings. A linear mixed effects model was used to test for familial association. The intra-class correlation coefficient (ICC) was used to determine the degree of association of the serum GM-CSF Ab level within families in comparison with the degree of association among families. The median (IQR) serum GM-CSF Ab concentration was higher in CD probands than in UC probands (1.5 [0.5,5.4] μg/mL vs 0.7 [0.3, 1.6] μg/mL, P = 0.0002). The frequency of elevated serum GM-CSF Ab concentration ≥1.6 μg/mL was increased in unaffected siblings of CD probands with elevated GM-CSF Ab, compared with unaffected siblings of CD probands without elevated GM-CSF Ab (33% vs 13%, respectively, P = 0.04). A similar result was observed within UC families. In families of CD patients, the mean (95th CI) ICC was equal to 0.153 (0.036, 0.275), P = 0.001, whereas in families of UC patients, the mean (95th CI) ICC was equal to 0.27 (0.24, 0.31), P = 0.047. These data confirmed familial association of serum GM-CSF Ab levels. This could be accounted for by either genetic or environmental factors shared within the family.

Immunoadsorption to remove ß2 adrenergic receptor antibodies in Chronic Fatigue Syndrome CFS/ME

IntroductionInfection-triggered disease onset, chronic immune activation and autonomic dysregulation in Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME) point to an autoimmune disease directed against neurotransmitter receptors. We had observed elevated autoantibodies against ß2 adrenergic receptors, and muscarinic 3 and 4 acetylcholine receptors in a subset of patients. Immunoadsorption (IA) was shown to be effective in removing autoantibodies and improve outcome in various autoimmune diseases.Methods10 patients with post-infectious CFS/ME and elevated ß2 autoantibodies were treated with IA with an IgG-binding column for 5 days. We assessed severity of symptoms as outcome parameter by disease specific scores. Antibodies were determined by ELISA and B cell phenotype by flow cytometry.ResultsIgG levels dropped to median 0.73 g/l (normal 7–16 g/l) after the 4th cycle of IA, while IgA and IgM levels remained unchanged. Similarly, elevated ß2 IgG antibodies rapidly decreased during IA in 9 of 10 patients. Also 6 months later ß2 autoantibodies were significantly lower compared to pretreatment. Frequency of memory B cells significantly decreased and frequency of plasma cells increased after the 4th IA cycle. A rapid improvement of symptoms was reported by 7 patients during the IA. 3 of these patients had long lasting moderate to marked improvement for 6–12+ months, 2 patients had short improvement only and 2 patients improved for several months following initial worsening.ConclusionsIA can remove autoantibodies against ß2 adrenergic receptor and lead to clinical improvement. B cell phenotyping provides evidence for an effect of IA on memory B cell development. Data from our pilot trial warrants further studies in CFS/ME.

MRI findings in glutamic acid decarboxylase associated autoimmune epilepsy.

Glutamic acid decarboxylase (GAD65) has been implicated in a number of autoimmune-associated neurologic syndromes, including autoimmune epilepsy. This study categorizes the spectrum of MRI findings in patients with a clinical diagnosis of autoimmune epilepsy and elevated serum GAD65 autoantibodies. An institutional database search identified patients with elevated serum GAD65 antibodies and a clinical diagnosis of autoimmune epilepsy who had undergone brain MRI. Imaging studies were reviewed by three board-certified neuroradiologists and one neuroradiology fellow. Studies were evaluated for cortical/subcortical and hippocampal signal abnormality, cerebellar and cerebral volume loss, mesial temporal sclerosis, and parenchymal/leptomeningeal enhancement. The electronic medical record was reviewed for relevant clinical information and laboratory markers. A study cohort of 19 patients was identified. The majority of patients were female (84%), with a mean age of onset of 27years. Serum GAD65 titers ranged from 33 to 4415nmol/L (normal < 0.02nmol/L). The most common presentation was medically intractable, complex partial seizures with temporal lobe onset. Parenchymal atrophy was the most common imaging finding (47%), with a subset of patients demonstrating cortical/subcortical parenchymal T2 hyperintensity (37%) or abnormal hippocampal signal (26%). No patients demonstrated abnormal parenchymal/leptomeningeal enhancement. The most common MRI finding in GAD65-associated autoimmune epilepsy is disproportionate parenchymal atrophy for age, often associated with abnormal cortical/subcortical T2 hyperintensities. Hippocampal abnormalities are seen in a minority of patients. This constellation of findings in a patient with medically intractable epilepsy should raise the possibility of GAD65 autoimmunity.

Quantitative thyroid scintigraphy for the differentiation of Graves' disease and hyperthyroid autoimmune thyroiditis.

The TCTUs (global (99m)Tc-pertechnetate thyroid uptake under suppression) can be used as an estimate of the iodine clearance of non-TSH regulated tissue. High TCTUs levels are characteristic for Graves' disease (GD). Decreased uptake has been described in autoimmune thyroiditis (AIT). However, systematically investigated data in a larger series of AIT-patients with subclinical or overt hyperthyroidism are not published so far. The purpose of this study is the evaluation of the TCTUs in the differentiation between AIT and GD in patients with hyperthyroidism. We determined the TCTUs in 59 patients with untreated hyperthyroid GD and in 51 patients with AIT who had subclinical or manifest hyperthyroidism without medication. Patients with GD were characterized by the presence of hyperthyroidism, decreased echogenicity of the thyroid, elevation of TSH-receptor autoantibodies (TRAb). AIT was defined by a decreased echogenicity of the thyroid, absence of elevated TSH-receptor autoantibodies (TRAb), autoantibodies against the thyroid peroxidase (anti-TPO) and spontaneous remission or development of subclinical hypothyroidism within 3 months. Thyroid volumes of patients with AIT were significantly lower than those of patients with GD (p <0.05). TRAb levels were significantly higher in GD-patients (median: 19.5 U/ml; range: 15.3-35 U/ml) than in AIT-patients (median: 1.3 U/ml; range: 0-4.1 U/ml). 73% (38/59) of patients with GD had elevated anti-TPO levels. In these patients anti-TPO levels (median: 768 U/l; range: 83-6397 U/l) were not significantly different from anti-TPO levels of patients with AIT (median: 834 U/l; range: 107-8675 U/l; p = 0.17). TCTUs values of patients with AIT were significantly lower (p <0.05; median: 0.9%; range: 0.1-3.2%) than those of patients with GD (median: 5.7%; range: 1.9-28.3%). In our patients quantitative thyroid scintigraphy with (99m)TcO(4)(-) offered rapid and reliable differentiation between hyperthyroid GD and AIT.

Thyroid Autoantibodies and the Clinical Presentation of Moyamoya Disease: A Prospective Study

Moyamoya is a rare cerebrovascular disease characterized by the progressive occlusion of the intracranial carotid artery. Thyroid autoantibodies have been found to be associated with the disease, but their clinical significance has never been studied. The objective of this study was to investigate the relationship between thyroid autoantibodies and the clinical presentation of moyamoya. This is a prospective study including 37 patients with moyamoya disease (MMD) or unilateral moyamoya (uMM). Thyroid function and thyroid autoantibodies (e.g., antithyroperoxidase and antithyroglobulin) were investigated. We studied the effect of gender, age, type of moyamoya (uMM versus MMD), and thyroid autoantibodies on the clinical presentation, dichotomized into aggressive (hemorrhage, major stroke, or frequent transient ischemic attack [TIA]) and nonaggressive presentation (headache, rare TIAs, and incidental diagnosis) according to the criteria of the Research Committee on Spontaneous Occlusion of the Circle of Willis. Of the 37 patients included in the study, the autoantibodies were elevated in 9 (24.3%). An aggressive presentation occurred in 21 patients (hemorrhage in 11, major stroke in 9, frequent TIAs in 1). The autoantibodies were elevated in 8 of the 21 patients (38.09%) with an aggressive presentation and in 1 of those presenting with minor symptoms (6.2%). The presence of elevated autoantibodies was the only variable associated with an aggressive presentation in the multivariate logistic analysis (P = .048). When the serum concentration of the thyroid autoantibodies is increased, the patients have a higher risk of an aggressive presentation. Our results support the hypothesis that activation of immune-mediated processes affects the moyamoya physiopathology.

Association of Hyperthyroidism and Thyroid Autoantibodies with Moyamoya Disease and Its Stroke Event: A Population-based Case-control Study and Meta-analysis.

The aim of this study was to investigate the specific thyroid condition and thyroid autoantibodies in adult moyamoya disease (MMD) according to clinical presentation (ischemia vs. hemorrhage stroke). In addition, a meta-analysis was performed to reveal the association between adult MMD and elevated thyroid function, or autoantibodies. Prospectively collected data on 169 consecutive patients with MMD at a single institution were analyzed. Community-based controls matched for age and sex were selected for comparison. Penalized multinomial logistic regression analysis was used for factors affecting stroke. For meta-analysis, heterogeneity was evaluated by using the I2 test. If I2 < 50%, a fixed effect model was used. Fifty-four cases (32.0%) presented with ischemic stroke and 37 cases (21.9%) with hemorrhage stroke. Hyperthyroidism had a marginally increased risk of MMD with ischemic stroke with reference value of MMD without stroke [odds ratio (OR), 2.53; P = 0.055]. Anti-thyroperoxidase antibody (TPOAb) increased the risk of MMD presenting with ischemic stroke significantly (OR, 2.99; P = 0.020). A meta-analysis revealed that adult MMD was significantly associated with elevated autoantibodies (OR, 7.663; P = 0.002) and hyperthyroidism (OR, 10.936; P < 0.001). Elevated TPOAb and hyperthyroidism may play important roles in adult MMD with ischemic stroke. Studies focusing on targeted hyperthyroidism and thyroid autoantibodies are necessary in treating adult MMD patients in the future.

Prevalence of Hepatocyte Growth Factor and Autoantibodies to α-HGF as a New Etiology for Bilateral Diffuse Uveal Melanocytic Proliferation Masquerading as Neovascular Age-Related Macular Degeneration.

Objective:The goal was to test the hypothesis that high serum hepatocyte growth factor (HGF) and retinal autoantibodies against α-HGF contribute to the pathology of bilateral diffuse melanocytic proliferation (BDUMP).Methods:Case report of an elderly diagnosed with neovascular age-related macular degeneration (n-AMD) treated with bilateral Bevacizumab injections. Examination included comprehensive ophthalmic examination and images obtained by fundus photography, fundus autofluorescence, fluorescein angiography, spectral-domain optical coherence tomography (OCT), and B-scan ultrasonography. The levels of HGF and circulating HGF receptor (c-MET) were measured in the serum by ELISA and anti-retinal autoantibodies by western blotting.Results:Patient received Bevacizumab injections for presumed n-AMD and had a history of papillary renal cell carcinoma stage 4 with a tumor containing gene mutation Y1230C in the mesenchymal-epithelial transition factor (MET). Visual acuity was 20/200 OD and CF OS. Multimodal imaging was consistent with BDUMP. Plasma exchange therapy was recommended but could not be started until 10 months later due to deterioration in his medical condition. Pre- and post-plasma exchange sera demonstrated anti-retinal autoantibodies against 69-kDa protein of the same molecular weight as the α-HGF. Serum autoantibodies reacted with purified recombinant α-HGF on the blot.Conclusions:BDUMP can mimic n-AMD, which can delay treatment. Plasma exchange resulted in resolved inflammation, resolution of exudative detachments and improved vision after cataract surgery. Consideration of the tumor genetics led to the recognition of elevated HGF levels and autoantibodies to α-HGF (anti-69-kDa), which suggested a new pathogenic mechanism of BDUMP. We believe that therapy with tyrosine kinase inhibitors and a checkpoint inhibitor may contribute to the high HGF levels and subsequent immune response.

Elevation of Autoantibody in Patients with Ischemic Stroke.

Recent clinical research has revealed a significant correlation between atherosclerosis, one of the primary etiologies of ischemic stroke, and the immune system. Assuming that “disease-specific autoantibodies are produced in the sera of patients with ischemic stroke,” we investigated multiple arteriosclerosis-related antibodies using the serological identification of antigens by recombinant cDNA expression cloning (SEREX), an established method for identifying antigenic proteins. We either screened a human aortic endothelial cell cDNA library or conducted protein array screening using the sera from patients with ischemic stroke, such as carotid artery stenosis or transient ischemic attack (TIA). Next, we measured serum antibody levels using amplified luminescent proximity homogeneous assay-linked immunosorbent assay (AlphaLISA) in patient/healthy donor (HD) cohorts and identified several antigens, the antibody levels of which were significantly higher in patients with ischemic stroke than in HDs. This review introduced the method of identifying antigens by the SEREX and protein microarray and summarized antigenic proteins. In particular, it focused on anti-replication protein A2 antibody and anti-programmed cell death 11 antibody, which are significantly related to atherosclerotic plaque and ischemic brain tissue, respectively, and proposed the mechanism of elevated autoantibody levels against them. Furthermore, this review suggests a possibility of clinical application as an atherosclerotic disease diagnostic marker for TIA or cerebral infarction.

Elevated Serum α-Synuclein Autoantibodies in Patients with Parkinson's Disease Relative to Alzheimer's Disease and Controls.

Early diagnosis of neurodegenerative diseases is of paramount importance for successful treatment. Lack of sensitive and early biomarkers for diagnosis of diseases like Parkinson’s disease (PD) is a handicapping problem for all movement disorders specialists. Using serum autoimmune antibodies (AIAs) against neural proteins is a new promising strategy to diagnose brain disorders through non-invasive and cost-effective method. In the present study, we measured the level of AIAs against α-synuclein (α-syn), which is an important protein involved in the pathogenesis of PD. In our study patients with PD (46 patients), Alzheimer’s disease (AD) (27 patients) and healthy controls (20 patients) were evaluated according to their sera α-syn AIAs levels. Interestingly, α-syn AIAs were significantly elevated in PD group compared to AD and healthy controls, which advocates their use for diagnosis of PD.

The ERM Protein Moesin Regulates CD8+ Regulatory T Cell Homeostasis and Self-Tolerance.

The ezrin-radixin-moesin (ERM) proteins are a family of membrane-associated proteins that link membrane proteins with actin filaments in the cell cortex and regulate many cellular processes, including cell shape determination, membrane transport, and signal transduction. Lymphocytes predominantly express two ERM members, ezrin and moesin. Mutations in the moesin gene in humans are associated with primary immunodeficiency with profound lymphopenia, and moesin-deficient mice exhibit a similar lymphopenia phenotype. In this study, we show that aging moesin-deficient mice develop a systemic lupus erythematosus-like autoimmune phenotype, which is characterized by elevated serum autoantibody levels and glomerulonephritis. Younger moesin-deficient mice exhibited elevated basal levels of several Ig isotypes and enhanced Ab affinity maturation upon immunization. Germinal center B cells and follicular helper T cells spontaneously accumulated in unimmunized mice, and CD8+CD44+CD122+Ly49+ regulatory T (CD8+ Tregs) cells, which inhibit the expansion of follicular helper T cells, were severely reduced in these mice. Isolated CD8+ Treg cells from moesin-deficient mice showed impaired proliferation in response to IL-15, which was accompanied by defects in STAT5 activation and IL-15Rα internalization, suggesting that moesin plays a key role in IL-15-mediated signaling. These findings underscore the importance of moesin in IL-15-dependent CD8+ Treg cell homeostasis and, thus, the control of self-tolerance.

Neural autoantibodies in patients with neurological symptoms and histories of chemical/mold exposures.

A number of studies have linked exposures to industrial and household chemicals and biological toxins to increased risk of autoimmunity in general and elevated levels of autoantibodies to neural antigens specifically. Elevated neural autoantibodies are biomarkers for many diseases such as multiple sclerosis and Parkinson's disease. Our study reports levels of six types of neural autoantibodies in a group of 24 toxicant-exposed patients. The patients were exposed to a variety of toxicants including contaminated drinking water (four patients), building water/mold damage (eight patients), pesticides (four patients), and other assorted toxic chemicals (eight patients). Levels of all six neural autoantibodies were significantly elevated in most patients and in the patient group at large, with mean antibody levels for the 24 chemically exposed patients (relative to a healthy control population), in descending order: 475% for tau proteins, 391% for microtubule associated proteins-2, 334% for neurofilament proteins (NFP), 302% for myelin basic protein, 299% for glial fibrillary acidic proteins, and 225% for tubulin. Tau protein autoantibodies were significantly elevated in the patient groups with peripheral neuropathy, muscle and joint pain, asthma, and chemical sensitivity. Autoantibodies to tubulin were significantly higher in the chemical sensitivity and asthma patients, autoantibodies to NFP were significantly higher in the patients with sleep apnea, whereas S-100B autoantibodies were significantly increased in patients with muscle/joint pain, asthma, and apnea/insomnia. In patients exposed to environmental toxicants, measurements of autoantibodies may be useful for prevention, diagnosis, and treatment. This study adds to the scientific literature the ability of a broad spectrum of environmental triggers adversely affecting the nervous system through the process of autoimmunity, which may explain the increasing incidence of neurodegenerative diseases.

Elevation of TP53 Autoantibody Before CA125 in Preclinical Invasive Epithelial Ovarian Cancer.

Purpose: The TP53 tumor-suppressor gene is mutated in >95% of high-grade serous ovarian cancers. Detecting an autologous antibody response to TP53 that might improve early detection.Experimental Design: An immunoassay was developed to measure TP53 autoantibody in sera from 378 cases of invasive epithelial ovarian cancer and 944 age-matched healthy controls from the United States, Australia, and the United Kingdom. Serial preclinical samples from cases and controls were also assayed from the UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS).Results: Using a cutoff value of 78 U/mL to achieve a specificity of 97.4%, TP53 autoantibody was elevated in 30% of 50 cases from MD Anderson, 21.3% of 108 cases from the Australian Ovarian Cancer Study, and 21% of 220 cases from the UKCTOCS. Among 164 cases with rising CA125 detected with the UKCTOCS risk of ovarian cancer algorithm (ROCA), 20.7% had elevated TP53 autoantibody. In cases missed by the ROCA, 16% of cases had elevated TP53 autoantibody. Of the 34 ovarian cancer cases detected with the ROCA, TP53 autoantibody titers were elevated 11.0 months before CA125. In the 9 cases missed by the ROCA, TP53 autoantibody was elevated 22.9 months before cancer diagnosis. Similar sensitivity was obtained using assays with specific mutant and wild-type TP53.Conclusions: TP53 autoantibody levels provide a biomarker with clinically significant lead time over elevation of CA125 or an elevated ROCA value. Quantitative assessment of autoantibodies in combination with CA125 holds promise for earlier detection of invasive epithelial ovarian cancer. Clin Cancer Res; 23(19); 5912-22. ©2017 AACR.

Elevated semaphorin 5A in patients with Hashimoto's thyroiditis: a case-control study.

ObjectiveHashimoto’s thyroiditis (HT) is characterized by elevated specific auto-antibodies, including TgAb and TPOAb. Increasing evidence has demonstrated the essential role of Th17 cells in HT. However, the underlying mechanism is still unclear. Semaphorin 5A (Sema 5A) is involved in several autoimmune diseases through the regulation of immune cells. The aim of the present study was to explore the role of Sema 5A in HT.MethodsWe measured serum Sema 5A levels in HT (n = 92) and healthy controls (n = 111) by enzyme-linked immunosorbent assay (ELISA). RNA levels of Sema 5A and their receptors (plexin-A1 and plexin-B3), as well as several cytokines (IFN-γ, IL-4 and IL-17), were detected by real-time polymerase chain reaction in peripheral blood mononuclear cells from 23 patients with HT and 31 controls. In addition, we investigated the relationship between serum Sema 5A and HT.ResultsSerum Sema 5A in HT increased significantly compared with healthy controls (P < 0.001). Moreover, serum Sema 5A levels were positively correlated with TgAb (r = 0.511, P < 0.001), TPOAb (r = 0.423, P < 0.001), TSH (r = 0.349, P < 0.001) and IL-17 mRNA expression (r = 0.442, P < 0.001). Increased Sema 5A RNA expression was observed (P = 0.041) in HT compared with controls. In receiver-operating characteristic (ROC) analysis, serum Sema 5A predicted HT with a sensitivity of 79.35% and specificity of 96.40%, and the area under the curve of the ROC curve was 0.836 (95% CI: 0.778–0.884, P < 0.001).ConclusionsThese data demonstrated elevated serum Sema 5A in HT patients for the first time. Serum Sema 5A levels were correlated with thyroid auto-antibodies and IL-17 mRNA expression. Sema 5A may be involved in immune response of HT patients.

Pleuroparenchymal fibroelastosis in heterogeneous clinical conditions: Clinicopathologic analysis of 7 cases.

Pleuroparenchymal fibroelastosis (PPFE) is classified as a rare idiopathic interstitial pneumonia, and its clinicopathologic features remain unclear. We sought to investigate the clinical, radiologic, and pathologic features of patients with histologically proven PPFE. Seven patients who had histologic features of PPFE that were definitive or consistent with PPFE were included. Clinical data and radiologic findings of chest computed tomography were obtained. Histologic evaluation was performed by 2 pathologists. Four patients had elevated serum autoantibodies, 3 had a history of organ transplantation, and 1 had acute Aspergillus infection. All patients had various degrees of restrictive patterns on pulmonary function tests. Histologic examination revealed a variable extent of PPFE. Fibroblastic foci, patchy lymphocytic infiltration, and pneumothorax were observed, but these findings were nonspecific. Radiologically, PPFE lesions were distributed diffusely, rather than being limited to the upper lungs. PPFE seems to be a histologic finding that may partly overlap with other chronic lung diseases. There can be various underlying clinical states.

Transplanted human fecal microbiota enhanced Guillain Barr\xe9 syndrome autoantibody responses after Campylobacter jejuni infection in C57BL/6 mice

BackgroundCampylobacter jejuni is the leading antecedent infection to the autoimmune neuropathy Guillain-Barré syndrome (GBS), which is accompanied by an autoimmune anti-ganglioside antibody attack on peripheral nerves. Previously, we showed that contrasting immune responses mediate C. jejuni induced colitis and autoimmunity in interleukin-10 (IL-10)-deficient mice, dependent upon the infecting strain. Strains from colitis patients elicited T helper 1 (TH1)-dependent inflammatory responses while strains from GBS patients elicited TH2-dependent autoantibody production. Both syndromes were exacerbated by antibiotic depletion of the microbiota, but other factors controlling susceptibility to GBS are unknown.MethodsUsing 16S rRNA gene high-throughput sequencing, we examined whether structure of the gut microbial community alters host (1) gastrointestinal inflammation or (2) anti-ganglioside antibody responses after infection with C. jejuni strains from colitis or GBS patients. We compared these responses in C57BL/6 mice with either (1) stable human gut microbiota (Humicrobiota) transplants or (2) conventional mouse microbiota (Convmicrobiota).ResultsInoculating germ-free C57BL/6 wild-type (WT) mice with a mixed human fecal slurry provided a murine model that stably passed its microbiota over >20 generations. Mice were housed in specific pathogen-free (SPF) facilities, while extra precautions of having caretakers wear sterile garb along with limited access ensured that no mouse pathogens were acquired. Humicrobiota conferred many changes upon the WT model in contrast to previous results, which showed only colonization with no disease after C. jejuni challenge. When compared to Convmicrobiota mice for susceptibility to C. jejuni enteric or GBS patient strains, infected Humicrobiota mice had (1) 10-100 fold increases in C. jejuni colonization of both strains, (2) pathologic change in draining lymph nodes but only mild changes in colon or cecal lamina propria, (3) significantly lower Th1/Th17-dependent anti-C. jejuni responses, (4) significantly higher IL-4 responses at 5 but not 7 weeks post infection (PI), (5) significantly higher Th2-dependent anti-C. jejuni responses, and (6) significantly elevated anti-ganglioside autoantibodies after C. jejuni infection. These responses in Humicrobiota mice were correlated with a dominant Bacteroidetes and Firmicutes microbiota.ConclusionsThese data demonstrate that Humicrobiota altered host-pathogen interactions in infected mice, increasing colonization and Th-2 and autoimmune responses in a C. jejuni strain-dependent manner. Thus, microbiota composition is another factor controlling susceptibility to GBS.

Crosstalk between type II NKT cells and T cells leads to spontaneous chronic inflammatory liver disease

Natural killer T (NKT) cells are CD1d-restricted innate-like T cells that modulate innate and adaptive immune responses. Unlike the well-characterized invariant/type I NKT cells, type II NKT cells with a diverse T cell receptor repertoire are poorly understood. This study defines the pathogenic role of type II NKT cells in the etiology of chronic liver inflammation. Transgenic mice with the Lck promoter directing CD1d overexpression on T cells in Jα18 wild-type (Lck-CD1dTgJα18+; type I NKT cell sufficient) and Jα18-deficient (Lck-CD1dTgJα18o, type I NKT cell deficient) mice were analyzed for liver pathology and crosstalk between type II NKT cells and conventional T cells. CD1d expression on T cells in peripheral blood samples and liver sections from autoimmune hepatitis patients and healthy individuals were also examined. Lck-CD1dTgJα18o and Lck-CD1dTgJα18+ mice developed similar degrees of liver pathology resembling chronic autoimmune hepatitis in humans. Increased CD1d expression on T cells promoted the activation of type II NKT cells and other T cells. This resulted in Th1-skewing and impaired Th2 cytokine production in type II NKT cells. Dysfunction of type II NKT cells was accompanied by conventional T cell activation and pro-inflammatory cytokine production, leading to a hepatic T/B lymphocyte infiltration, elevated autoantibodies and hepatic injury in Lck-CD1dTg mice. A similar mechanism could be extended to humans as CD1d expression is upregulated on activated human T cells and increased presence of CD1d-expressing T cells was observed in autoimmune hepatitis patients. Our data reveals enhanced crosstalk between type II NKT cells and conventional T cells, leading to a Th1-skewed inflammatory milieu, and consequently, to the development of chronic autoimmune liver disease. Lay summary: CD1d overexpression on T cells enhances crosstalk between type II NKT cells and T cells, resulting in their aberrant activation and leading to the development of chronic autoimmune liver disease.

Abstract 710: Identification of autoantibody to ECH1 &amp; HNRNPA2B1 as potential biomarkers in the early detection of lung cancer

Abstract Background: Identification of biomarkers for early detection of lung cancer (LC) may lead to more effective treatment and reduction of mortality. Methods: Serological proteome analysis (SERPA) was used to identify proteins around 34 kDa, which had been previously recognized by autoantibody in sera from LC patients. We have validated autoantibody response in sera from 90 LC patients, 89 normal controls by using immunoassay. Another independent cohort of 25 LC patients with 219 serial serum samples and 56 matched normal controls were examined to evaluate whether the autoantibody can be detected in the preclinical stage. Results: The proteins with molecular weight of 34 kDa were identified as ECH1, GAPDH and HNRNPA2B1. In the validation study, autoantibody to ECH1 achieved an area under the curve (AUC) of 0.799 with sensitivity of 62.2% and specificity of 95.5% in discriminating LC from normal individuals, and showed negative correlation with tumor size (rs=0.-256, p=0.023). Autoantibody to HNRNPA2B1 performed an AUC of 0.874 with sensitivity of 72.2% and specificity of 95.5%, and showed negative correlation with lymph node metastasis (rs=0.-279, P=0.012). By using longitudinal preclinical samples, autoantibody to ECH1 showed an AUC of 0.763 with sensitivity of 60.0% and specificity of 89.3% in distinguishing LC with matched normal controls, and elevated autoantibody levels could be detected greater than two years prior to LC diagnosis. Conclusions: ECH1 and HNRNPA2B1 are autoantigens that elicit autoimmune responses in LC and can be used as potential biomarkers for the early detection of LC. Funding support: This work was supported by the National Natural Science Foundation of China (81672917, 81372371) and the National Institutes of Health (SC1CA166016 and U01CA086137). Citation Format: Liping Dai, Jitian Li, Jun-Chieh J. Tsay, Xiao Wang, John S. Munger, Harvey Pass, William N. Rom, Eng M. Tan, Jian-Ying Zhang. Identification of autoantibody to ECH1 &amp; HNRNPA2B1 as potential biomarkers in the early detection of lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 710. doi:10.1158/1538-7445.AM2017-710

Sex-related differences in autoimmune-induced lung lesions in MRL/MpJ-faslpr mice are mediated by the development of mediastinal fat-associated lymphoid clusters

MRL/MpJ-Faslpr (lpr) mice are a model for autoimmune diseases such as systemic lupus erythematosus (SLE). These diseases mainly affect women, with a 10:1 female-to-male ratio, and cause pleuropulmonary lesions. We previously revealed a correlation between mediastinal fat-associated lymphoid cluster (MFALC) development and cellular infiltration in the lungs of lpr male mice; however, we did not report on MFALCs in females. The purpose of this investigation was to reveal sex-related differences in MFALCs in lpr mice. We compared the morphological features of MFALCs and lung mononuclear cell aggregates (LMCAs) in 5-month-old male and female lpr mice. The females showed significantly elevated anti-dsDNA autoantibody titers and larger MFALCs, with a higher ratio of lymphatic vessel (LV) and high endothelial venule (HEV) areas to MFALC area, and greater numbers of T- and B-cells, macrophages, and proliferating and dendritic cells in MFALCs and LMCAs than males. Our data indicated that MFALCs were more developed and lung lesions were more severe in female than in male lpr mice, thereby suggesting a potential role for LVs and HEVs in the establishment of MFALCs and lung lesions. Further investigation in female lpr mice will be needed for treatment of human respiratory diseases and autoimmune disorders.

Identification of autoantibodies to ECH1 and HNRNPA2B1 as potential biomarkers in the early detection of lung cancer

ABSTRACTIdentification of biomarkers for early detection of lung cancer (LC) is important, in turn leading to more effective treatment and reduction of mortality. Serological proteome analysis (SERPA) was used to identify proteins around 34 kD as ECH1 and HNRNPA2B1, which had been recognized by serum autoantibody from 25 LC patients. In the validation study, including 90 sera from LC patients and 89 sera from normal individuals, autoantibody to ECH1 achieved an area under the curve (AUC) of 0.799 with sensitivity of 62.2% and specificity of 95.5% in discriminating LC from normal individuals, and showed negative correlation with tumor size (rs = −0.256, p = 0.023). Autoantibody to HNRNPA2B1 performed an AUC of 0.874 with sensitivity of 72.2% and specificity of 95.5%, and showed negative correlation with lymph node metastasis (rs = −0.279, p = 0.012). By using longitudinal preclinical samples, autoantibody to ECH1 showed an AUC of 0.763 with sensitivity of 60.0% and specificity of 89.3% in distinguishing early stage LC from matched normal controls, and elevated autoantibody levels could be detected greater than 2 y before LC diagnosis. ECH1 and HNRNPA2B1 are autoantigens that elicit autoimmune responses in LC and their autoantibody can be the potential biomarkers for the early detection of LC.