Expression and Functional Role of HLA-G in Immune Cells from Patients with Systemic Lupus Erythematosus

Human leukocyte antigen (HLA)-G is a class I non-classical HLA molecule with an important regulatory role on the immune response. The possible role of this molecule in the pathogenesis of SLE has not been explored. In this work, we evaluated the expression and function of HLA-G in SLE patients. We studied 37 SLE patients as well as 25 healthy donors. Peripheral blood monocytes and in vitro-generated dendritic cells (DCs) were analyzed for HLA-G expression by flow cytometry. We found that monocytes from SLE patients as well as mature CD83+ DCs showed a diminished expression of HLA-G compared with healthy controls. In addition, monocytes from SLE patients showed a diminished induction of HLA-G expression in response to stimulation with IL-10. Furthermore, functional assays showed that these monocytes pre-treated with IFN-γ exhibited a diminished capability to inhibit the proliferation of autologous lymphocytes. Finally, lymphocytes from SLE patients tended to display a lower acquisition of HLA-G (by trogocytosis) from autologous monocytes compared to controls. Our results might have implications for the immune abnormalities observed in patients with SLE.     

Association of increased serum IL-33 levels with clinical and laboratory characteristics of systemic lupus erythematosus in Chinese population

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by abnormal production of autoantibodies and proinflammatory cytokines. Although interleukin-33 (IL-33), a novel number of the IL-1 family, has been reported to have proinflammatory effects, the association of IL-33 with SLE has remained unknown. The aim of this study was to examine whether the serum IL-33 level is associated with SLE. A total of 70 patients with SLE were recruited. Sera from these patients were obtained at their visit and were compared to sera from 40 healthy controls or 28 patients with rheumatoid arthritis (RA) for IL-33 level. Furthermore, blood samples from patients with SLE were determined for various SLE-related laboratory variables, including blood routine, complements, erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) and some autoantibodies. Serum IL-33 level was significantly increased in patients with SLE, compared with healthy controls, but was lower than that with RA. In patients with SLE, most clinical and laboratory characteristics did not correlate with serum IL-33 levels, with exceptions of thrombocytopenia, erythrocytopenia, anti-SSB antibody, ESR, CRP and IgA. By Spearman’s correlation coefficient, patients with SLE showed close correlation of IL-33 with ESR, CRP and IgA, and by multivariate logistic regressions, patients with SLE showed significantly independent association of IL-33 with thrombocytopenia, erythrocytopenia and anti-SSB antibody. Our results suggest that IL-33 may play a role in acute phase of SLE, but it was not associated with course of the disease. Moreover, IL-33 may exert biologic effects on erythrocytes and platelets or their precursors in SLE.     

Matrix metalloproteinase-9 and its natural inhibitor TIMP-1 expressed or secreted by peripheral blood mononuclear cells from patients with systemic lupus erythematosus

Matrix metalloproteinase-9 (MMP-9) was involved in inflammation and immune system dysfunctions. Besides immunologic abnormalities, systemic lupus erythematosus (SLE) also presents chronic inflammatory components. Therefore, a role of MMP-9 in SLE pathology might be supposed. To verify this hypothesis, SLE patients and healthy donors were compared for the MMP-9 and MMP-9 mRNA levels in peripheral blood mononuclear cells (PBMCs), the spontaneous secretion of MMP-9 and TIMP-1 and the MMP-9 activity. Thus, we found that fresh PBMCs from SLE patients expressed a significantly higher activity of MMP-9 and spontaneously released higher levels of MMP-9, as compared to healthy donors, while the secreted TIMP-1 level was the same for both groups. When the patients were sub-grouped based on disease status, the most increased pro-MMP-9 activity inside the PBMCs was identified for relapse SLE sub-group. A similar observation for SLE patients with positive serum fibrinogen was found. Following culture, the PBMCs from remission SLE patients secreted significantly higher MMP-9 level, than the PBMCs from relapse SLE patients. PBMCs from relapse SLE patients secreted the highest levels of TIMP-1, although this difference was not statistically significant. Taken together, these observations suggested the multiple roles of MMP-9 and TIMP-1 in progress of inflammation and tissue damage and/or in repair, depending on clinical stages of SLE.     

Microarray analysis of autoantibodies can identify future Systemic Lupus Erythematosus patients

ObjectiveReliable early ascertainment in patients with SLE is important to prevent the accumulation of irreversible organ damage. Autoantibodies are often present in the serum of patients before the first symptoms arise, therefore they are of potential use as early diagnostic tools.MethodsWe used a custom-made antibody microarray containing 57 autoantigens to analyze serum samples of 1519 patients previously tested for anti-dsDNA and 361 samples of self-reported healthy blood bank donors (BBD). The 1519 patients included 483 patients with SLE, 346 patients with other immune mediated inflammatory diseases (IMID), 218 patient controls without relevant clinical symptoms (Non-IMID), and 472 patients that did not fit in any of the previous groups (Rest). The Non-IMID and BBD groups were used individually to create multivariable prediction models to distinguish samples of patients with SLE from these control groups. We subsequently used these models to predict the outcome for samples of patients who developed SLE while in follow-up (pre-SLE).ResultsOut of 1036 patients with no diagnosis of SLE at the moment of sample collection, 17 patients developed SLE while in follow-up (mean time to diagnosis 7.2 months). The best performing model (AUC 0.83) identified 9 out of 17 (53%) pre-SLE samples as SLE, with a specificity of 94%.ConclusionSerum samples of patients who will develop SLE in the future already show a shift of the autoantibody profile prior to diagnosis. In this study, we show that these autoantibody profiles can be used to identify these future SLE patients.     

Phenotypic analysis of IL-10-treated, monocyte-derived dendritic cells in patients with systemic lupus erythematosus

Dendritic cells (DC) play a dual role in the immune response, participating in its induction, and the maintenance of immune tolerance. The aim of this work was to perform a quantitative and phenotypic analysis of DC generated in vitro in the presence of IL-10 in patients with systemic lupus erythematosus (SLE). Blood samples were obtained from 10 active and untreated patients with SLE and six controls. Monocyte-derived DC were generated in vitro in the presence or absence of IL-10, and a quantitative and phenotypic analysis was performed. We found that freshly isolated monocytes from SLE patients had an increased expression of CD11b. On the other hand, the efficiency of in vitro DC generation was diminished in blood samples from SLE patients for conventional DC, but not for IL-10-treated DC. A diminished expression of HLA-DR, CD9 and CD86 was observed in conventional DC from SLE patients compared with controls. In contrast, enhanced levels of HLA-DR, CD80, CD9 and CD151 tetraspanins, FN1 (a class II MHC-tetraspanin epitope), CD85j/ILT2 and CD69 were detected in IL-10-treated DC from SLE patients. Accordingly, the phenotypic profile of IL-10-treated DC was very different in SLE and controls. However, the synthesis of IL-10 and IL-12 was similar in IL-10-treated and conventional cells in both SLE patients and controls. Our findings on the aberrant phenotype of IL-10-treated DC in SLE and their normal efficiency of in vitro generation may be important for the design of future therapies of this condition based on the administration of DC to induce immune tolerance.     

Increased CCR4 expression in active systemic lupus erythematosus.

CC chemokine receptor (CCR)4 is selectively expressed on Th2-type T cells and has been shown to be responsible for Th2-dominant immune responses. In this study, we analyzed the expression of CCR4 in active systemic lupus erythematosus (SLE) patients by FACS analysis using anti-human CCR4 monoclonal antibody and determined the clinical relevance in this disease. Higher expression of CCR4 was found on peripheral blood CD4+ T lymphocytes of active SLE patients than was found with healthy controls and inactive SLE patients. The CCR4 expression significantly correlated with the SLE disease activity index (SLEDAI) scores. The expression was dramatically decreased after the corticosteroid therapy in parallel with a serum level of double-stranded DNA antibody and SLEDAI scores. Moreover, we found that serum levels of IL-10 were increased in active SLE patients and significantly correlated with the CCR4 expression. This study suggests that Th2 immune response is predominant in the active state of SLE, and CCR4 may have relevance in regard to the disease course in SLE patients.     

Interferon production of vitro by leucocytes from patients with systemic lupus erythematosus and rheumatoid arthritis.

The production of interferons (IFN) by peripheral blood leucocytes from normal donors an patients with systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) has been investigated in response to several IFN inducers in vitro. Whereas IFN responses of RA donors did not differ significantly from the normal group, those of SLE patients were significantly reduced, and many of these patients failed to respond to all. Patients with active or acute SLE responded significantly less well than those with inactive disease. There was no apparent effect of steroid therapy on the IFN responses of either SLE or RA patients. These data may indicate a basic immunological defect of the circulating leucocytes of SLE patients, which may be responsible for some of the in vitro lymphocyte anomalies reported for this disease.     

G/T polymorphism in the interleukin-2 exon 1 region among Han Chinese systemic lupus erythematosus patients in Taiwan

Interleukin-2 (IL-2), one of the crucial immunoregulatory cytokines required for T lymphocyte activation, plays an important role in autoimmune diseases. An IL-2 genetic G/T polymorphism (rs2069763) has been linked with multiple sclerosis and rheumatoid arthritis. We tested a hypothesis that this polymorphism confers systemic lupus erythematosus (SLE) susceptibility. Study participants were Han Chinese SLE patients and a healthy control group in Taiwan. Our results indicate (a) a significantly higher G allele frequency in SLE patients (P=1.91 x 10(-14); OR=3.94; 95% CI=2.74-5.66), (b) a significantly higher G allele frequency in SLE patients with antinuclear antibodies (ANA) (P=0.033; OR=4.21; 95% CI=1.01-17.51) and (c) a significantly lower G allele frequency in SLE patients with discoid rash (P=0.019; OR=0.41; 95% CI=0.19-0.88). Our results suggest that this polymorphism may be involved in the genetic background of Taiwanese SLE.     

Two distinct subsets of patients with systemic lupus erythematosus

This study was undertaken to examine the levels and function of peripheral blood immunoregulatory T cell subpopulations in systemic lupus erythematosus (SLE). T cell subpopulations can be distinguished by the T cell differentiation antigens CD4 (recognized by the monoclonal antibodies OKT4 or Leu3) and CD8 (recognized by the monoclonal antibodies OKT8 or Leu2). All SLE patients tested had normal percentages of CD8 cells in their peripheral blood. The SLE patients, however, fell into two groups based on their CD4 cell numbers. Fifty-five percent of the SLE patients had normal levels of CD4 cells (Group A) and therefore normal CD4/CD8 cell ratios, whereas 45% of the SLE patient population had markedly depressed CD4 cell levels (Group B) and significantly low CD4/CD8 cell ratios. T cells from normal donors and SLE patients were further examined for their ability to stimulate allogeneic normal B/M phi cells to secrete IgM in the presence of pokeweed mitogen (PWM). Utilizing this assay system two forms of immunosuppression were observed: (1) that mediated by high concentrations of purified CD4 cells and (2) that mediated by CD8 cells. High concentrations of purified CD4 cells, added to a constant number of allogeneic normal B/M phi cells, suppressed PWM-stimulated IgM synthesis. Group B SLE patients, with significantly low CD4 cell numbers, had defective CD4 cell-mediated suppression which was concentration dependent. This result was confirmed in a study using identical twins discordant for SLE. In this case CD4 cells from the SLE twin did not induce immunosuppression at a high concentration of CD4 cells whereas similar concentrations of CD4 cells from the normal twin resulted in suppression. SLE patients (Group A) with normal levels of CD4 cells had normally immunosuppressive CD4 cells. Suppression mediated by CD8 cells was demonstrated by the fact that removal of CD8 cells resulted in enhanced IgM synthesis induced by the remaining CD4 cells. Although all the SLE patients in this study had normal peripheral blood levels of CD8 cells, SLE Group A patients had defective CD8 cell suppression whereas CD8 function appeared to be normal in Group B patients. These results suggest that in SLE patients with depressed CD4 cell numbers (Group B) there is a corresponding defect in CD4 cell function. We demonstrate that in SLE Group B patients, defective suppression is due to a subset of T cells that bear the CD4 antigen. The SLE patient population (Group A) with normal CD4/CD8 ratios and normally functioning CD4 cells, however, appear to have normal CD4 cell-mediated suppression but defective CD8 suppressor cell function.     

Analysis of expression and function of the inhibitory receptor ILT2 (CD85j/LILRB1/LIR-1) in peripheral blood mononuclear cells from patients with systemic lupus erythematosus (SLE)

The aim of this work was to study the expression and function of the inhibitory receptor ILT2/CD85j in peripheral blood mononuclear cells (PBMC) from patients with systemic lupus erythematosus (SLE). We studied 23 SLE patients as well as 17 patients with rheumatoid arthritis, 10 with fibromyalgia, and 23 healthy individuals. We found a variable level of expression of ILT2 in the PBMC from both SLE patients and controls, with no significant differences among them. However, when the expression of this receptor was assessed in cell subsets, significantly lower levels were detected in CD19+ lymphocytes from SLE patients compared with healthy controls. Functional assays performed in unfractionated PBMC, showed a significant diminished inhibitory activity of ILT2 in CD4+ and CD8+ cell subsets from SLE patients compared to either rheumatoid arthritis or fibromyalgia patients, and healthy individuals. Our results show that the PBMC from some patients with SLE show a defective expression of ILT2, and that most of them exhibit a poor function of this inhibitory receptor.     

Altered expression of signalling lymphocyte activation molecule (SLAM) family receptors CS1 (CD319) and 2B4 (CD244) in patients with systemic lupus erythematosus

CS1 (CRACC, CD319) and 2B4 (CD244), members of the signalling lymphocyte activation molecule (SLAM) family receptors, regulate various immune functions. Genes encoding SLAM family receptors are located at 1q23, implicated in systemic lupus erythematosus (SLE). In this study, we have investigated the expression and alternative splicing of CS1 and 2B4 in immune cells from SLE patients. The surface expression of CS1 and 2B4 on total peripheral blood mononuclear cells (PBMCs), T, B, natural killer (NK) cells and monocytes in 45 patients with SLE and 30 healthy individuals was analysed by flow cytometry. CS1‐positive B cell population was increased significantly in SLE patients. Because CS1 is a self‐ligand and homophilic interaction of CS1 induces B cell proliferation and autocrine cytokine secretion, this could account for autoreactive B cell proliferation in SLE. The proportion of NK cells and monocytes expressing 2B4 on their surface was significantly lower in patients with SLE compared to healthy controls. Our study demonstrated altered expression of splice variants of CS1 and 2B4 that mediate differential signalling in PBMC from patients with SLE.     

Correlation of plasma and urine Wnt5A with the disease activity and cutaneous lesion severity in patients with systemic lupus erythematosus

Reliable noninvasive biomarkers are needed to accurately assess disease activity and prognosis in patients with systemic lupus erythematosus (SLE). The purpose of this study was to investigate the clinical relevance of Wnt5A with disease activity and severity with cutaneous involvement in particular in SLE patients; its concentrations in plasma and urine were examined and analyzed. In the cross-sectional study, the clinical relevance of Wnt5A protein was evaluated in both plasma and urine of SLE patients and healthy cohorts using commercial enzyme-linked immunosorbent assays (ELISA). Significantly, more abundances of Wnt5A protein were determined in both of plasmas and urines of SLE patients compared to healthy cohorts (p < 0.0001), which were even higher in active disease (AD) SLE patients relative to low disease activity (LDA) SLE patients (p < 0.0001). Meanwhile, the ROC curve analysis demonstrated that the plasma and urine Wnt5A were potential candidate biomarkers for identifying the disease activity and severity in SLE patients. The discriminant function analysis further revealed that the plasma and urine Wnt5A were separated and distinct for AD SLE patients and healthy controls. In consistence, the disease severity was correlated with the plasma and urine Wnt5A as ascertained by CLASI activity score and the prevalence of serositis in SLE patients. These results suggest that Wnt5A, as a summary measure for different inflammatory processes, could be a potential biomarker for accessing the disease activity, and a noninvasive biomarker for evaluating the disease severity in terms of cutaneous involvement in SLE patients.

     

Premature atherosclerotic disease in systemic lupus erythematosus--role of inflammatory mechanisms

Mounting evidence from a growing body of epidemiologic studies demonstrates that patients with systemic lupus erythematosus (SLE) are at increased risk for the development of premature cardiovascular disease (CVD). However, awareness of accelerated atherosclerosis in young SLE patients, albeit growing, is still limited, as documented by the brief case presented. Inflammation is thought to play an important role in both the pathogenesis of SLE, as well as atherosclerotic vascular disease. Inflammatory processes that are shared by SLE and atherosclerotic disease include immune complex deposition and fixation, autoantibody binding, complement activation and CD40-CD40 ligand interaction. By examining the inflammatory mechanisms in common between SLE and atherosclerotic disease, we can come to a better understanding of the pathophysiology of the accelerated atherosclerotic process seen in patients with SLE and can gain insights into developing and instituting preventative and treatment strategies. In this article, we present a case of a young woman with SLE who presents with chest pain, followed by a review of inflammation-based pathogenic mechanisms that are shared by SLE and atherosclerotic cardiovascular disease.     

DR3 and nonDR3 associated complement component C4A deficiency in systemic lupus erythematosus

The molecular basis of complement component C4A deficiency in white U.S. and Mexican patients with systemic lupus erythematosus (SLE) was studied. Genomic DNA from SLE patients and non-SLE controls was analyzed for restriction fragments using HindIII and a 5' C4 cDNA probe. C4A gene deletion was recognized by the loss of a 15-kb restriction fragment and the appearance of a 8.5-kb fragment. Thirty-two selected U.S. SLE patients, 7 nonSLE controls, and 11 Mexican SLE patients and 9 relatives were studied. The deletion was recognized in all of the 14 HLA-B8;DR3 SLE patients with a C4A protein deficiency. Two SLE patients with DR3 but without B8 also had this gene deletion. None of the 3 U.S. SLE nonDR3, C4A protein deficient patients nor 20 C4A protein deficient Mexican individuals (11 SLE patients and 9 relatives; none had B8 and/or DR3) showed this deletion. Thus the C4A gene deletion failed to account for the C4A protein deficiency in all the nonDR3 Mexicans and in some U.S. SLE patients. To determine whether gene conversion at the C4A locus would encode a C4B-like protein and be responsible for the C4A protein deficiency (in nonDR3 patients), the C4d region of the gene was amplified by polymerase chain reaction and subjected to Nla IV digestion, and restriction fragment analysis was performed using a C4d region-specific probe. The resulting restriction fragment length polymorphism pattern revealed no changes in the isotype-specific region of the gene as characterized by C4A-specific 276- and 191-bp fragments in Dr3 or nonDR3 individuals. Thus, homoexpression of C4B at both loci was not responsible for C4A deficiency in nonDR3 SLE patients without C4A gene deletion.     

Microcomputer-generated antigen panel worksheets

Early reports of anti-Rodgers (anti-Rg) noted that there was an increased number of the HLA-B8 phenotype among this group. This HLA type has recently been Linked to a C4A (Rg) gene deletion found with increased frequency among systemic lupus erythematosus (SLE) patients. Healthy controls (n= 176) and SLE patients (n=102) were studied for their HLA haplotype and C4 allotype as well as their Rg phenotype Six of 53 white and 3 of 49 black SLE patients were C4A-null and Rodgers-negative, a significant difference from controls p=.002). A retrospective study of patients who produced ant-Rg showed that one third had symptoms often associated with SLE but none had SLE as a primary diagnosis.     

Appearance of systemic lupus erythematosus in patients with myasthenia gravis following thymectomy: two case reports

We report two cases of systemic lupus erythematosus (SLE) in myasthenia gravis (MG) patients who had undergone thymectomy. SLE developed in the patients 3 months or 13 yr after thymectomy, and polyarthritis was the main clinical manifestation of SLE. Both patients fulfilled at least four of the revised criteria for the classification of SLE. In this report, we describe two postthymectomy lupus patients and perform a comparative review of previous cases.     

Association analysis of the PTPN22 gene in childhood-onset systemic lupus erythematosus in Mexican population

Several studies have identified a functional single nucleotide polymorphism 1858C/T in the PTPN22 gene to be associated with several autoimmune diseases. Association studies of this polymorphism with familial and sporadic systemic lupus erythematosus (SLE) have shown some discrepancies. To our knowledge, this is the first study that includes only pediatric-onset SLE patients. We performed a case-control association study in 250 unrelated Mexican patients with childhood-onset SLE consisting of 228 cases with sporadic SLE and 22 cases with familial SLE and 355 healthy controls. We observed a statistically significant difference in the frequency of the PTPN22 1858T allele between SLE patients (3.4%) and healthy controls (1.1%) (P=0.0062, odds ratio (OR) 3.09 (95% confidence interval 1.32-7.21)). The association was also observed when only sporadic cases were analyzed (OR=3.19). Our results support the association of the PTPN22 1858T allele with sporadic childhood-onset SLE in Mexican population.     

Analysis of antigen specific T cell helper function in first degree relatives of patients with systemic lupus erythematosus (SLE).

Fourteen families with first degree relatives of patients with systemic lupus erythematosus (SLE) were studied for the ability of their members to respond to the synthetic polypeptide antigen (T,G)-A-L. The family members were also tested for their HLA determinants. All SLE patients tested responded to (T,G)-A-L as measured by the production of (T,G)-A-L specific T cell helper factors by their antigen activated T cells, confirming our previous findings that 100% of SLE donors responded to (T,G)-A-L in contrast to 50% responders in a control population of healthy donors. The general defect in the regulation of immune responses in SLE patients was further indicated by the demonstration that an SLE patient who is a daughter of non-responder parents to (T,G)-A-L, responded to this genetically regulated antigen. In contrast to our observations with SLE patients, the genetic regulation of the ability to respond to (T,G)-A-L was shown not to be impaired in healthy first degree family members of SLE patients and the segregation of the immune response potential in these families was as expected from an inherited dominant trait.     

Anti-mannose binding lectin antibodies in sera of Japanese patients with systemic lupus erythematosus

Mannose-binding lectin (MBL) is a key element in innate immunity with functions and structure similar to that of complement C1q. It has been reported that MBL deficiency is associated with occurrence of systemic lupus erythematosus (SLE). We hypothesized that anti-MBL antibodies, if present, would affect the occurrence or disease course of SLE, by reduction of serum MBL levels, interference of MBL functions, or binding to MBL deposited on various tissues. To address this hypothesis, we measured the concentration of anti-MBL antibodies in sera of 111 Japanese SLE patients and 113 healthy volunteers by enzyme immunoassay. The titres of anti-MBL antibodies in SLE patients were significantly higher than those in healthy controls. When the mean + 2 standard deviations of controls was set as the cut off point, individuals with titres of anti-MBL antibodies above this level were significantly more frequent in SLE patients (9 patients) than in controls (2 persons). One SLE patient had an extremely high titre of this antibody. No associations of titres of anti-MBL antibodies and (i) genotypes of MBL gene, (ii) concentrations of serum MBL, or (iii) disease characteristics of SLE, were apparent. Thus, we have confirmed that anti-MBL antibodies are indeed present in sera of some patients with SLE, but the significance of these autoantibodies in the pathogenesis of SLE remains unclear.     

Hyperthyroidism association with SLE,lessons from real-life data – A case–control study

Background: Despite the frequently encountered association between thyroid disease and systemic lupus erythematosus (SLE) is well known, it is of surprise that only several reports compromised of small population size support this observation. Objectives: To investigate the association of comorbid SLE and hyperthyroidism. Methods: Using the database of the largest health maintenance organization (HMO) in Israel, the Clalit Health Services, we searched for the co-existence of SLE and hyperthyroidism. Patients with SLE were compared with age- and sex-matched controls regarding the prevalence of hyperthyroidism in a case–control study. Chi-square and t-tests were used for univariate analysis and a logistic regression model was used for multivariate analysis. Results: The study included 5018 patients with SLE and 25?090 age- and sex- matched controls. The prevalence of hyperthyroidism in patients with SLE was increased compared with the prevalence in controls (2.59% and 0.91%, respectively, p?Conclusions: Patients with SLE have a greater prevalence of hyperthyroidism than matched controls. Therefore, physicians treating patients with SLE should be aware of this possibility of this thyroid dysfunction.