Circulating soluble CTLA-4 is related to inflammatory markers in the 70 year old population.

OBJECTIVE: Measurement of inflammatory mediators is an important tool to assess inflammation. We have, therefore, conducted a survey within the Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS) study to evaluate the inter-relationship between soluble CTLA-4 (sCTLA-4) and other inflammatory markers. MATERIALS AND METHODS: This is a population-based study, designed to quantify the circulating serum levels of sCTLA-4 and other inflammatory markers such as CRP and pro-inflammatory cytokines and chemokines by in-house ELISA, Immuno-turbidimetry and multiplex ELISA, respectively. A total of 1016 Swedish Caucasians aged 70 years old were recruited. The statistical analysis was performed by ANOVA. RESULTS: The levels of sCTLA-4 were directly related to the levels of pro-inflammatory cytokines such as IL-6, IL-1alpha, IL-1beta, TNF-alpha, IFN-gamma and chemokines such as IL-8. However, the levels of sCTLA-4 were inversely related to the levels of MCP-1. Also, we could not demonstrate any relation between the levels of sCTLA-4 and CRP or soluble adhesion molecules. CONCLUSIONS: Circulating sCTLA-4 could be used as a biomarker for inflammation, potentially reflecting dysregulated T lymphocytes.

Polymorphisms in PDCD1 gene are not associated with Wegener's granulomatosis.

Genetic association of programmed cell death-1 (PDCD1) has been implicated in several autoimmune inflammatory disorders. Hence, in this study, our main objective is to evaluate the association of PDCD1 gene to Wegener's granulomatosis (WG). We, thus, analyzed three single nucleotide polymorphisms (SNPs) in PDCD1 gene among WG patients and controls. Further, we quantified circulating serum levels of soluble (s) PD-1 in patients and controls. The methodologies used were ABI Taqman allelic discrimination and restriction fragment length polymorphism for genotyping and in-house ELISA for quantifying sPD-1. Statistical relevance was analyzed by Fischer's exact test. As a result, reduced AA homozygote for SNP in intron-1 was observed, among the patients. However, no association was demonstrated after Bonferroni correction. Also, no differences in genotype and allele frequency were elucidated for SNPs in intron-4 and exon-5. Moreover, we could not demonstrate circulating sPD-1. In conclusion, we show no association of selected SNPs in PDCD1 gene with WG.

Identification of CTLA-4 isoforms produced by alternative splicing and their association with myasthenia gravis.

Myasthenia gravis (MG) is an autoimmune disease characterized by muscle weakness induced by autoantibodies against the acetylcholine receptor. CTLA-4 (CD152) plays an inhibitory role in the immune response and has been suggested to be involved in the pathophysiology of MG. In this study, we focused on alternative CTLA-4 mRNA expression in PBMCs from MG patients. We defined two new isoforms of CTLA-4 mRNA that arise due to alternative splicing. By semi-quantitative RT-PCR analysis, we observed a lower expression of sCTLA-4 mRNA relative to the membrane form in MG patients. In addition, the MG patients had lower levels of sCTLA-4 mRNA in PBMCs compared to healthy controls, as assessed by real-time PCR. One of the spliced isoforms (LCTLA-4) was more prevalent in MG patients compared to healthy controls. The alternative splicing was not associated with sex, thymectomy, serum levels of anti-AChR, immunosuppressive treatment or the four CTLA-4 gene polymorphisms analyzed. This study reveals an abnormal spectrum of mRNA expression of CTLA-4 in MG patients, which marks the importance of studying gene expression of alternative splicing.

PTPN22 R620W promotes production of anti-AChR autoantibodies and IL-2 in myasthenia gravis.

In order to investigate the potential involvement of PTPN22 R620W in the pathogenesis of myasthenia gravis (MG), we performed a case-control study including 409 Swedish MG patients and 1557 normal controls. The W620 variant was significantly overrepresented in patients (odds ratio, 1.52; 95% confidence interval, 1.21-1.90; p=0.00027). Incubation of patient (n=100) derived PBMC cells with the autoantigen, the acetylcholine receptor, resulted in a significantly higher number of cells producing anti-AChR antibodies and IL-2 in W620 carriers, suggesting that PTPN22 W620 may be a loss-of-function variant in MG.

Programmed Death-1: from gene to protein in autoimmune human myasthenia gravis.

The key role of an inhibitory receptor, Programmed Death-1, has been evaluated in 273 patients with autoimmune myasthenia gravis. At the genetic level, SNP's genotyping showed no significant association to the disease. Gene expressions in patients were not different from that in controls. Interestingly, at the cell-surface protein level, there were significant elevated levels of PD-1 on T cells and its ligand PD-L1 on monocytes in the patients compared to controls. However, we could not demonstrate any secreted soluble forms of PD-1 among the patients and controls. Thus, our study shows PD-1 might have a natural regulatory property behind MG.

Soluble costimulatory factors sCD28, sCD80, sCD86 and sCD152 in relation to other markers of immune activation in patients with myasthenia gravis.

The costimulatory factors CD28, CD80, CD86 and CD152 needed to start and turn off an immune response are present as membrane receptors and soluble proteins. There was no difference in the serum levels of soluble costimulatory molecules in 153 healthy controls and 118 patients with myasthenia gravis. However, we could confirm that the soluble forms of ICAM-1 and CD25 were increased in patients. The concentrations of the soluble costimulatory proteins seemed to be rather constant in individual patients, despite changes in clinical presentation. Thus, the soluble costimulatory factors do not seem to constitute reliable markers for disease activity in myasthenia gravis.

Myasthenia gravis: a long term follow-up study of Swedish patients with specific reference to thymic histology.

BACKGROUND: Myasthenia gravis (MG) is an autoimmune disorder of neuromuscular transmission. The majority of patients show abnormal thymic histology. SETTING: The study was performed at the Myasthenia Gravis Centre, Karolinska University Hospital, and at the Immunological Research Laboratory, Centre for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden. PATIENTS AND METHODS: Information was collected retrospectively from 1956 and prospectively from 1975 on clinical data, concomitant diseases, concentration of serum acetylcholine receptor antibodies (AChR-abs), immunosuppressive treatment (IS) and response to it, in 537 patients of whom 326 were thymectomised. Follow-up time was 1.5-50 years. RESULTS: Age at onset of MG increased from a median age of 24 years before 1975 to a median age of 61 years after 2000. Thymoma was found in 65, hyperplasia (HPL) in 185 and a normal thymus in 76 patients. The trans-sternal surgical approach for thymectomy was used in 255 patients (78%). In five patients with thymoma, MG appeared after thymectomy. Of 537 patients, 466 (87%) had circulating AChR-abs. IS was given to 300 (56%) patients, mostly those with thymoma (85%). In total, 441 patients (82%) showed an improvement. One-third of patients with HPL, a quarter of those with thymoma, one-fifth of those with a normal thymus and one-seventh of those not operated on went into remission. CONCLUSION: The prognosis for the majority of patients with MG is favourable, irrespective of thymic histology. The cause may be the use of immunomodulating therapy.

Aggressive behavior linked to corticotropin-reactive autoantibodies.

BACKGROUND: Altered stress response is characteristic for subjects with abnormal aggressive and antisocial behavior, but the underlying biological mechanisms are unclear. We hypothesized that autoantibodies (autoAbs) directed against several stress-related neurohormones may exist in aggressive subjects. METHODS: Using enzyme-linked immunosorbent assay, we studied whether autoAbs directed against corticotropin (ACTH), alpha-melanocyte-stimulating hormone (alpha-MSH), oxytocin, and vasopressin are present in serum of male subjects with conduct disorder and prisoners with history of violence. Healthy blood donors served as control subjects. RESULTS: Both conduct disorder and prisoners groups displayed strongly increased levels of ACTH-reactive immunoglobulin G (IgG) and immunoglobulin M (IgM) autoAbs compared with control subjects. Levels of oxytocin-reactive IgM autoAbs were slightly increased in both groups of aggressive subjects, whereas levels of vasopressin-reactive IgG and IgM autoAbs were lower only in conduct disorder. No differences in the levels of alpha-MSH-reactive autoAbs were found between aggressive and control subjects. CONCLUSIONS: High levels of ACTH-reactive autoAbs as well as altered levels of oxytocin- and vasopressin-reactive autoAbs found in aggressive subjects may interfere with the neuroendocrine mechanisms of stress and motivated behavior. Our data suggest a new biological mechanism of human aggressive behavior that involves autoAbs directed against several stress-related neurohormones.

B7-H3 and B7-H4 expression in non-small-cell lung cancer.

Inhibitory regulatory functions of B7-H3 and B7-H4 regarding T-cell activation have been reported recently. Little is known about the significance of human B7-H3 and B7-H4 expression in non-small-cell lung cancer (NSCLC), and we conducted the present study to address this issue in cell lines and tumor tissue from 70 patients. B7-H3 is over-expressed by all six NSCLC cell lines on both mRNA and protein level. B7-H4 is only transcripted by one cell line in which an alternatively spliced form was discovered. In tumor tissues, expression of B7-H3 and B7-H4 was found both on the cell membrane and in the cytoplasm. Thirty-seven percent of the specimens expressed B7-H3 and 43% B7-H4. The number of T infiltrating lymphoid cells (TILs) in the tumor tissues that expressed B7-H3 or B7-H4 was much lower than those who did not. There was a significant positive relation between the expression of B7-H3 and B7-H4, and high B7-H3 or B7-H4 expression was significantly more common in cases with lymph node metastasis. These observations suggest the contribution of B7-H3 and B7-H4 to immune dysfunction and tumor progression in NSCLC patients. B7-H3 and B7-H4 may be an important target for diagnosis and/or therapy of NSCLC.

Polymorphisms of IL-1beta, IL-1Ra, and TNF-alpha genes: a nested case-control study of their association with risk for stroke.

Certain alleles of cytokine genes interleukin-1 beta (IL-1beta), interleukin-1 receptor antagonist (IL-1Ra), and tumor necrosis factor alpha (TNF-alpha) are correlated with increased production of the proteins. The aim of this study was to investigate polymorphisms of these genes and their possible correlation with the development of stroke. This matched case-control study was nested within the population-based Västerbotten Intervention Program (VIP) cohort and the Northern Sweden World Health Organization MONICA (Multinational Monitoring of Trends and Determinants in Cardiovascular Diseases) cohort, based on individuals who were free from cardiovascular events when the cohorts were established. After an average period of 34.1 months, 113 individuals developed stroke and to each case 2 individuals not suffering from cardiovascular events were matched to serve as controls. Polymerase chain reaction amplification was used to analyze genetic polymorphisms. There was no association between polymorphic sites of the IL-1beta and IL-1Ra genes and stroke. Carriage of haplotype A2+IL-1beta/A2+IL-1Ra was significantly increased in normotensive cases (23.1%) compared with normotensive controls (8.9%) (odds ratio [OR] = 3.07; P = .045). In hypertensive male cases, there was an association between the A1A1 genotype of TNF-alpha and risk of stroke (OR = 2.46; P = .034). Our findings indicate an association between allele A1 of the TNF-alpha NcoI polymorphism and stroke in hypertensive male cases, as well as an association between haplotype A2+IL-1beta/A2+IL-1Ra and stroke in normotensive cases.

Dendritic cells activate autologous T cells and induce IL-4 and IL-10 production in myasthenia gravis.

Dendritic cells (DC), as initiators and orchestrators of immune responses, control both naive and primed T cell responses. Depending on their maturation stage, DC promote immunity or tolerance. Here we investigated (1) the phenotype and cytokine secretion patterns of IL-10-modulated immature DC (IL-10-DC) and lipopolysaccharide (LPS)-driven mature DC (LPS-DC) in comparison with unmodulated immature DC (imDC) and (2) the effects of IL-10-DC, and of LPS-DC, vs. imDC on autologous T cell responses in patients with myasthenia gravis (MG) compared with healthy controls (HC). All three types of DC derived from MG significantly increased the levels of CD4+CD25+ T cells and of their subfraction expressing CD69, when compared to DC derived from HC. IL-10-DC induced production of IL-10 and IL-4 by T cells from MG patients, but only IL-10 production from HC. LPS-DC activated autologous T cells as reflected by augmented CD25, CD69 and CTLA-4 expression on CD4+ T cells, without differences between MG and HC. This was associated with increased production of both Th1 (IFN-gamma) and Th2 (IL-10 and IL-4) cytokines by T cells. These results indicate that DC-induced activation of autologous T cells is more pronounced in MG than in HC. In addition, DC-induced T cell responses in MG vs. HC are more Th2-prone.

Abnormal expression of CTLA-4 by T cells from patients with myasthenia gravis: effect of an AT-rich gene sequence.

Cytolytic T lymphocyte-associated antigen-4 (CTLA-4) plays a critical role in the down-regulation of antigen-activated immune responses. The aberrant CTLA-4 expression is characterized by low surface and intracellular levels of CTLA-4 protein, impaired up-regulation of CTLA-4 in T cells in response to ConA stimulation and high levels of soluble CTLA-4 (sCTLA-4) in serum. The serum levels of sCTLA-4 are positively correlated with the serum concentration of antibodies against the acetylcholine receptor. The (AT)(n) polymorphism in the 3'-untranslated region contributes to decreased mRNA stability and, hence, to reduced expression of CTLA-4.

Genotypes of CCR2 and CCR5 chemokine receptors in human myasthenia gravis.

The aim of this study was to examine the association of human autoimmune myasthenia gravis (MG) with two DNA polymorphisms of the chemokine receptors CCR5-Delta 32 and CCR2-64I. CCR2 and CCR5 interact primarily with the human CC family ligands CCL2 (formerly called monocyte chemoattractant protein; MCP-1), CCL3 and CCL4 (macrophage inflammatory protein-1 alpha and -1 beta; MIP-1 alpha/beta), and their main function is to recruit leukocytes from circulation into the tissues, thus playing an important role in human inflammatory disorders. A PCR-based genotyping method was used to determine the genetic variation at the CCR5 gene and an automated real-time Pyrosequencing technology was employed for the analysis of G right curved arrow A point mutation at the CCR2 gene. Results obtained from 158 patients and 272 healthy controls demonstrate no evidence of association between genetic variants of CCR2 and CCR5 with MG and its clinical manifestations. CCR2-64I and CCR5-Delta 32 genotypes are thus unlikely to be involved in protection or predisposition to MG.

Polymorphisms in the IL10 but not in the IL1beta and IL4 genes are associated with inhibitor development in patients with hemophilia A.

The aim of the Malmö International Brother Study (MIBS) is to evaluate host genetic factors associated with the development of inhibitory antibodies in patients with hemophilia. Factor VIII gene mutations and genetic polymorphisms of the IL1beta, IL4, and IL10 genes, known to influence antibody production in autoimmune diseases, were analyzed in 164 patients (124 with severe, 26 with moderate, and 14 with mild disease) in 78 unrelated families with hemophilia A. Seventy-seven (47%) patients in 54 families had a history of inhibitors (57 high responding, 20 low responding). Inversions were found in 36 families (75 patients). There was no association between the development of inhibitor and the IL1beta Taq I RFLP alleles in exon 5 or the -590 C/T single nucleotide polymorphism (SNP) in the promoter region of IL4. There was, however, a strong association between an allele with 134 bp in one of the CA repeat microsatellites, IL10G, located in the promoter region of the IL10 gene, and the development of inhibitor (odds ratio [OR], 4.4; 95% confidence interval [95% CI], 2.1-9.5; P < .001). The association was consistent in the subgroup of families with severe hemophilia and inversions. IL10 is the first gene located outside the causative factor VIII gene mutation to be associated with inhibitor development.

Polymorphisms in the TNFA gene and the risk of inhibitor development in patients with hemophilia A.

The HLA class I/II alleles and the tumor necrosis factor alpha (TNFA) locus are closely linked in the MHC complex. We have characterized the causative factor VIII mutation, HLA alleles as well as 4 polymorphisms (-827C>T, -308G>A, -238A>G, and 670A>G) in the TNFA gene in 164 patients (124 severe, 26 moderate, and 14 mild) in 78 families with hemophilia A enrolled in the Malmö International Brother Study (MIBS). Inhibitors were identified in 77.8% of patients with a single haplotype (Hap 2) and 72.7% of the patients with the TNFA -308 A/A genotype within this haplotype compared with 39.7% for TNFA -308 G/G patients and 46.9% for TNFA -308 G/A heterozygotes (OR 4.0; 95% CI, 1.4-11.5; P = .008). The association between the -308 A/A genotype and inhibitors was enhanced in subgroups of patients with severe hemophilia (OR 19.2; 95% CI 2.4-156.5; P < .001) and with inversions (n = 75; OR, 11.8; 95% CI, 1.3-105.1; P = .013). Associations were found for the HLA A26 and B44 alleles, but these were not consistent in the subgroup analysis. Our data imply that the TNFA -308G>A polymorphism within Hap 2 is a useful marker and potential modulator of the immune response to replacement therapy in patients with hemophilia.

Autoantibodies against neuropeptides are associated with psychological traits in eating disorders.

Previously, we identified that a majority of patients with anorexia nervosa (AN) and bulimia nervosa (BN) as well as some control subjects display autoantibodies (autoAbs) reacting with alpha-melanocyte-stimulating hormone (alpha-MSH) or adrenocorticotropic hormone, melanocortin peptides involved in appetite control and the stress response. In this work, we studied the relevance of such autoAbs to AN and BN. In addition to previously identified neuropeptide autoAbs, the current study revealed the presence of autoAbs reacting with oxytocin (OT) or vasopressin (VP) in both patients and controls. Analysis of serum levels of identified autoAbs showed an increase of IgM autoAbs against alpha-MSH, OT, and VP as well as of IgG autoAbs against VP in AN patients when compared with BN patients and controls. Further, we investigated whether levels of these autoAbs correlated with psychological traits characteristic for eating disorders. We found significantly altered correlations between alpha-MSH autoAb levels and the total Eating Disorder Inventory-2 score, as well as most of its subscale dimensions in AN and BN patients vs. controls. Remarkably, these correlations were opposite in AN vs. BN patients. In contrast, levels of autoAbs reacting with adrenocorticotropic hormone, OT, or VP had only few altered correlations with the Eating Disorder Inventory-2 subscale dimensions in AN and BN patients. Thus, our data reveal that core psychobehavioral abnormalities characteristic for eating disorders correlate with the levels of autoAbs against alpha-MSH, suggesting that AN and BN may be associated with autoAb-mediated dysfunctions of primarily the melanocortin system.

Coding sequence 1 and promoter single nucleotide polymorphisms in the CTLA-4 gene in Wegener's granulomatosis.

OBJECTIVE: To analyze the association of Wegener's granulomatosis (WG) with 2 single nucleotide polymorphisms (SNP), a +49 A/G polymorphism in coding sequence (CDS) 1 and a C/T base exchange in the promoter region at position -318. METHODS: Restriction enzyme digestion of PCR amplified genomic DNA was used to analyze the CTLA-4 SNP in 32 patients with WG and 100-122 ethnically matched healthy controls. RESULTS: Patients were more often heterozygous for C/T in the promoter region (31% of the patients vs 14% of controls; p < 0.05). Homozygosity for C was less frequent in patients (69% of patients vs 86% of controls; p < 0.05). There was no association with the A/G SNP in CDS 1. There was a linkage disequilibrium between allele A of CDS 1 and the shortest allele, 86 bp, in the (AT)n of the 3' untranslated region in controls but not in patients. CONCLUSION: The CTLA-4 SNP in the promoter region at position -318 is associated with WG. The loss of linkage disequilibrium between allele A of CDS 1 and the short 86 bp in the (AT)n in patients indicates that the promoter SNP and the (AT)n polymorphism are independent genetic risk factors.

Novel genetic association of Wegener's granulomatosis with the interleukin 10 gene.

OBJECTIVE: Wegener's granulomatosis (WG) is a necrotizing vasculitis characterized by clonal expansions of T cells and production of antibodies against proteinase 3. The disease is associated with expanded dinucleotide repeats in the cytotoxic T lymphocyte antigen 4 (CTLA-4) gene, suggesting that genetic variation(s) in T cell related gene(s) could contribute to the T cell hyperactivity in WG. We investigated the polymorphisms in the genes of 2 cytokines, interleukin 4 (IL-4) and IL-10, which are essential for the polarization of T cells towards Th2 development and for the Ig production by B cells. METHODS: Polymorphisms in the genes coding for IL-10 and IL-4 were analyzed in 32-36 Swedish Caucasian patients and 109 ethnically matched healthy individuals. RESULTS: There was no association with the IL-4 gene. A CA repeat polymorphism in IL-10 gene, IL-10.G, was associated with the disease. This polymorphism has earlier been associated with high autoantibody production. CONCLUSION: Our results indicate that the IL-10 gene may influence the disease, perhaps by influencing the production of autoantibodies.

Susceptibility for and clinical manifestations of rheumatoid arthritis are associated with polymorphisms of the TNF-alpha, IL-1beta, and IL-1Ra genes.

OBJECTIVE: To analyze the association of genetic polymorphisms of pro-inflammatory cytokines with rheumatoid arthritis (RA) in comparison with healthy controls from Northern Sweden and the potential contribution of these genetic variants for disease severity and development of cardiovascular complications. METHODS: Polymerase chain reaction amplification was used for analysis of TaqI restriction fragment length polymorphism (RFLP) of interleukin-1 beta (IL-1beta), variable tandem repeat polymorphism of IL-I receptor antagonist (IL-1Ra) gene and NcoI RFLP at position -308 of tumor necrosis factor-alpha (TNF-alpha) gene. One hundred and fifty-four patients with RA, 42 men and 112 women, were consecutively recruited into the study through the Department of Rheumatology. RESULTS: The allele A1 of TNF-alpha was more common in the patient group (p < 0.01; OR = 1.62). Patients having the genotype A1A2 seemed to develop more severe disease compared with patients with A1A1 genotype: they were younger at disease onset (p < 0.05), had a higher accumulated disease activity (p < 0.05) and worse functional class (p < 0.05). Patients with genotype A2A2 of IL- 1beta had higher accumulated disease activity score than patients with A1A1 and A1A2 (p < 0.05). The allelic combination Al IL-1beta/A2 IL-1Ra was less prevalent in RA patients who developed cardiovascular complications (p < 0.005; OR = 0.20). CONCLUSIONS: The Al allele of TNF-alpha associates with RA. Genotypes A1A2 of TNF-alpha and A2A2 of IL-1beta are associated with more severe disease. The allelic combination A1IL-1beta/A2 IL-1Ra is less often present in RA patients who developed cardiovascular complications.