Serum interleukin-17 levels are associated with nephritis in childhood-onset systemic lupus erythematosus

OBJECTIVES:

To determine the serum interleukin-17 (IL-17) levels in childhood-onset systemic lupus erythematosus patients and to evaluate the association between IL-17 and clinical manifestations, disease activity, laboratory findings and treatment.

METHODS:

We included 67 consecutive childhood-onset systemic lupus erythematosus patients [61 women; median age 18 years (range 11-31)], 55 first-degree relatives [50 women; median age 40 years (range 29-52)] and 47 age- and sex-matched healthy controls [42 women; median age 19 years (range 6-30)]. The childhood-onset systemic lupus erythematosus patients were assessed for clinical and laboratory systemic lupus erythematosus manifestations, disease activity [Systemic Lupus Erythematosus Disease Activity Index (SLEDAI)], cumulative damage [Systemic Lupus International Collaborating Clinics/American College of Rheumatology (ACR) Damage Index] and current drug use. Serum IL-17 levels were measured by an enzyme-linked immunosorbent assay using commercial kits.

RESULTS:

The median serum IL-17 level was 36.3 (range 17.36-105.92) pg/mL in childhood-onset systemic lupus erythematosus patients and 29.47 (15.16-62.17) pg/mL in healthy controls (p=0.009). We observed an association between serum IL-17 levels and active nephritis (p=0.01) and migraines (p=0.03). Serum IL-17 levels were not associated with disease activity (p=0.32), cumulative damage (p=0.34), or medication use (p=0.63).

CONCLUSION:

IL-17 is increased in childhood-onset systemic lupus erythematosus and may play a role in the pathogenesis of neuropsychiatric and renal manifestations. Longitudinal studies are necessary to determine the role of IL-17 in childhood-onset systemic lupus erythematosus.     

白介素17A受体在系统性红斑狼疮患者外周血B淋巴细胞的表达及意义

目的:研究白介素17A受体(IL-17AR)在系统性红斑狼疮(SLE)患者外周血B淋巴细胞内的表达情况及其临床意义。方法:流式细胞术检测60例SLE患者及33例健康人外周血B细胞上IL-17AR的表达水平。并将其与有关临床及实验室指标进行相关性分析。结果:SLE患者组的IL-17AR+细胞表达比例为(47.58±17.20)%,高于正常对照组(40.71±11.82)%(P<0.05)。在SLE患者中:口腔溃疡组、有浆膜炎组、有肾脏病变组、有免疫异常组分别高于相应的无症状组(P<0.05)。在抗Sm-D1抗体阳性组及抗核小体抗体阳性组分别高于相应的抗体阴性组(P<0.05)。IL-17AR+细胞比例与SLE疾病活动指数(SLEDAI)、C反应蛋白(CRP)、甘油三酯呈正相关;与间接胆红素、血清白蛋白的表达负相关(P<0.05)。B淋巴细胞比例与血清IgG、ALT、直接胆红素的表达呈正相关;与胆固醇、甘油三酯、低密度脂蛋白的表达呈负相关(P<0.05)。结论:IL-17AR在SLE患者B细胞上表达上调,且与病情有一定的相关性。提示IL-17/IL-17AR可能在SLE发病中起着重要作用。     

The effect of interleukin-10 and of interleukin-12 on the in vitro production of anti-double-stranded DNA antibodies from patients with systemic lupus erythematosus

IL-10 and IL-12 are cytokines which are important in regulating immune responses. Plasma levels of IL-10 and autoantibodies against double-stranded DNA (dsDNA) often mirror disease activity in patients with SLE. IL-12 secretion from SLE patients' blood mononuclear cells also correlates with disease activity, but has an inverse relationship. The aim of this study was to measure the effect of IL-10 and of IL-12 on the production of IgG autoantibodies from patients with SLE, both cross-sectionally and longitudinally. Peripheral blood mononuclear cells (PBMC) were cultured with IL-10 (at 20 ng/ml or 2 ng/ml) or IL-12 (at 2 ng/ml or 0.2 ng/ml) or without cytokine and the supernatanants tested for the production of double-stranded DNA antibodies (dsDNA abs), single-stranded DNA antibodies (ssDNA abs) and total IgG antibodies (IgG abs) by ELISA. The BILAG disease activity index was recorded at each patient visit (a global score of six or more is regarded as active disease). In general, treatment with IL-10 caused PBMCs from patients with inactive disease to increase their antissDNA and dsDNA ab production (by upto 354% and 186%, respectively) while patients with active disease decreased their antibody production (by upto 91% and 97%, respectively). Overall there was a correlation between disease activity and change in antissDNA and dsDNA ab production (r = - 0.51; P = 0.03 and r = - 0.48; P = 0.042, respectively). Treatment with IL-12 at 0.2 ng/ml inhibited antissDNA and dsDNA antibody production, having the greatest effect on patients with active disease (decreasing antissDNA and dsDNA antibody production by upto 75% and 73%, respectively). This resulted in a significant correlation between disease activity and change in antissDNA antibody production (r = - 0.76; P = 0.03), but significance was not reached with antidsDNA antibody production (P = 0.06). Together these data suggest that the effect of these cytokines on antibody production by SLE PBMCs involves several factors; one of which is disease activity.     

系统性红斑狼疮患者血清IL-10和IL-18的检测及意义

目的探讨系统性红斑狼疮（SLE）患者血清IL-10和IL-18的表达及其与疾病活动的关系。方法应用ELISA法检测104例SLE患者和100例健康体检者血清IL-10和IL-18的水平,其中SLE患者根据疾病活动性指数（SLEDAI）评分标准分为活动组（56例）和缓解组（48例）,比较各组结果的差异,并分析SLEDAI与IL-10和IL-18的相关性。结果 SLE组IL-10和IL-18水平分别为（18.25±3.66）、（582.61±65.28）pg/ml,明显高于对照组的（7.12±2.36）、（186.24±60.39）pg/ml,差异有统计学意义（P〈0.01）;SLE活动组IL-10和IL-18水平分别为（25.98±4.75）、（683.72±62.48）pg/ml,高于缓解组的（14.67±3.21）、（493.51±69.17）pg/ml,差异亦有统计学意义（P〈0.01）;SLE患者血清IL-10和IL-18水平与SLEDAI呈正相关（P〈0.05）。结论 IL-10和IL-18在SLE发病机制中发挥重要作用,而且与疾病活动性相关。     

Increased serum levels of soluble interleukin-2 receptor in patients with systemic lupus erythematosus and rheumatoid arthritis

In this study we investigated the serum levels of a released soluble form of the interleukin-2 receptor (sIL-2R) in 42 patients with rheumatoid arthritis and in 12 cases of systemic lupus erythematosus. Data were evaluated in relationship to the clinical phase and compared with those observed in normal controls (N=56) and in osteoarthritis (N = 7). Increased levels were observed in both rheumatoid arthritis (mean ± SE, 604±49 U/ml) and systemic lupus erythematosus (1438±481 U/ml). These values were significantly higher than in control (256±15 U/ml;P<0.001) and in osteoarthritis (298±33 U/ml;P<0.001) groups. In addition, the highest values were associated with the active phases of both rheumatoid arthritis (active vs inactive, 771±78 vs 451±39 U/ml;P<0.001) and systemic lupus erythematosus (active vs inactive, 2108±489 vs 499±75 U/ml;P<0.001). Our findings suggest that the detection of sIL-2R in rheumatoid arthritis and in systemic lupus erythematosus may represent a good marker of disease activity, which indirectly indicates the ongoing activation and/or proliferation of immunoreactive cells which are involved in the pathogenetic events of these autoimmune conditions.     

Haem oxygenase 1 expression is altered in monocytes from patients with systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by multiple functional alterations affecting immune cells, such as B cells, T cells, dendritic cells (DCs) and monocytes. During SLE, the immunogenicity of monocytes and DCs is significantly up-regulated, promoting the activation of self-reactive T cells. Accordingly, it is important to understand the contribution of these cells to the pathogenesis of SLE and the mechanisms responsible for their altered functionality during disease. One of the key enzymes that control monocyte and DC function is haem oxygenase-1 (HO-1), which catalyses the degradation of the haem group into biliverdin, carbon monoxide and free iron. These products possess immunosuppressive and anti-inflammatory capacities. The main goal of this work was to determine HO-1 expression in monocytes and DCs from patients with SLE and healthy controls. Hence, peripheral blood mononuclear cells were obtained from 43 patients with SLE and 30 healthy controls. CD14(+) monocytes and CD4(+) T cells were sorted by FACS and HO-1 expression was measured by RT-PCR. In addition, HO-1 protein expression was determined by FACS. HO-1 levels in monocytes were significantly reduced in patients with SLE compared with healthy controls. These results were confirmed by flow cytometry. No differences were observed in other cell types, such as DCs or CD4(+) T cells, although decreased MHC-II levels were observed in DCs from patients with SLE. In conclusion, we found a significant decrease in HO-1 expression, specifically in monocytes from patients with SLE, suggesting that an imbalance of monocyte function could be partly the result of a decrease in HO-1 expression.     

Complement receptor 1 (CR1) on erythrocytes of patients with systemic lupus erythematosus

Ninety-five (85%) of the 112 Japanese patients with systemic lupus erythematosus (SLE) were negative for the complement receptor 1 (CR1) activities on erythrocytes, while 770 (91%) of the 847 normal subjects were positive for CR1, as determined by immune-adherence hemagglutination. Pedigree analyses of the normal population suggested that the phenotype of negative CR1 was determined by a autosomal recessive gene. Among 112 SLE patients, 73 (65%) showed persistently negative CR1 during remission for over 26 months of follow-up, although the CR1 levels did vary with the disease activity in 22 SLE patients. These results show that the relative risk for developing SLE in persons with negative CR1 is 19. CR1 activity appears to be an important genetic factor related the development of SLE.     

狼疮性肾炎患者外周血IL-18水平及其基因表达

为了探讨白细胞介素 18(IL 18)在狼疮性肾炎 (LN )发生、发展中的作用。我们采用逆转录多聚酶链反应 (RT PCR )及酶联免疫吸附 (ELISA )法测定 16例正常人及 18例LN患者外周血单个核细胞 (PBMC )IL 18mRNA表达量及其血浆水平。结果提示LN患者PBMCIL 18mRNA表达量及血浆IL 18水平均较正常对照组显著增高 [IL 18mRNA表达量为 :1 2 6 2± 0 189vs0 84 4± 0 15 5 ,P <0 0 0 1;IL 18血浆水平为 :(82 2 0 9± 5 32 77)pg/mlvs (2 39 5 7± 75 0 6 )pg/ml,P <0 0 0 1]。且WHOIV型LN增高较非IV型LN更为显著 [IL 18mRNA表达量为 :1 32 9± 0 2 1vs 1 138± 0 15 2 3,P <0 0 5 ;IL 18血浆水平为 :(1135 5 4± 5 15 34)pg/mlvs (5 0 8 6 5± 341 36 )pg/ml,P <0 0 1]。另外 ,血浆IL 18水平与肾组织活动指数 ,肾小管间质损害程度呈等级相关 (r分别为 :0 6 10和 0 4 99,P均 <0 0 5 ) ,也与血清肌酐 (Scr) ,血清内生肌酐清除率 (Ccr)及 2 4h尿蛋白排泄量 (2 4hUPQ )呈直线相关 (r分别为 :0 898、 0 6 2 8和 0 5 37,P均 <0 0 5 )。本研究认为循环IL 18表达和分泌增高可能参与LN的免疫发病过程 ,并与狼疮活动有一定的关系     

Cytokine-independent progression of immunoglobulin production in vitro by B lymphocytes from patients with systemic lupus erythematosus.

B lymphocytes from patients with systemic lupus erythematosus (SLE) secreted high levels of immunoglobulin spontaneously when cultured in vitro. Addition of the cytokines interleukin-2, interleukin-4 and interleukin-6 either alone or in combination failed to augment spontaneous immunoglobulin synthesis. Percoll-separated low-density SLE B lymphocytes matured into immunoglobulin-secreting cells also independent of exogenous interleukins. During maturation these cells became enlarged and less dense, and began to express CD23. This was in contrast to normal B cells, which did not secrete immunoglobulin spontaneously but synthesized IgM after interleukin stimulation. These results indicate that in vitro immunoglobulin synthesis by SLE B cells is already initiated in these cells and progresses independently of further stimulatory manoeuvres.     

The synergistic effect of FC gamma receptor IIa and interleukin-10 genes on the risk to develop systemic lupus erythematosus in Thai population

Several linkage analyses have consistently shown that systemic lupus erythematosus (SLE) susceptible genes are located on chromosome 1q21-44. In this study, two major candidate genes, interleukin-10 (IL-10) and Fc gamma receptor IIa (FcgammaRIIa), within these regions were investigated in Thai SLE patients. The genotyping of three single-nucleotide polymorphisms (promoter area: -1082, -819 and -592) within IL-10 gene and one polymorphism (change amino acid at position 131) within FcgammaRIIa gene was determined in 195 SLE patients and 159 ethnically matched controls. The RR/RH genotypes of FcgammaRIIa were found to be significantly increased in SLE patients compared with healthy controls [OR = 2.01, 95% confidence interval (CI) = 1.28-3.14, P= 0.001]. Interestingly, the synergistic effect between RR/RH genotypes of FcgammaRIIa and ACC/ACC haplotype of IL-10 in susceptibility to SLE was observed (OR = 7.84, 95% CI = 1.60-52.04, P= 0.002). In addition, the FcgammaRIIa, RR homozygotes was also strongly associated with anticardiolipin antibody production (OR = 6.09, 95% CI = 1.38-30.54, P= 0.006). The result demonstrated that ACC haplotype of IL-10 gene and FcgammaRIIa R131 polymorphism can be used as marker for genetic susceptibility and severity to SLE in Thai population, particularly individuals carrying both specific genotypes.     

CD134 expression on CD4+ T cells is associated with nephritis and disease activity in patients with systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is characterized by a deviation of the immune system that involves T cell-dependent autoantibody production. The aim of this study was to investigate the role of co-stimulatory markers on T cells in this disease. Twenty-eight patients with SLE as defined by the American College of Rheumatology (ACR) criteria and 11 healthy controls were included into the study. Eleven patients had biopsy-proven lupus nephritis while 17 patients had no clinical evidence of lupus nephritis. Clinical disease activity was assessed according to the systemic lupus erythematosus disease index (SLEDAI). CD4+ T cell populations in the peripheral blood were analysed for the expression of co-stimulatory markers CD45RO, CD70, CD80, CD86, CD137, CD137L, CD134, CD152, CD154 and ICOS. SLE patients showed an increased frequency of peripheral CD4+ T cells expressing high levels of CD80, CD86 and CD134 compared to healthy controls (7.1 +/- 1.5% versus 1.7 +/- 0.9%; P < 0.005; 2.3 +/- 0.4% versus 1.0 +/- 0.2%; P = 0.008, 20.2 +/- 2.0% versus 10.6 +/- 1.9%; P < 0.005, respectively). Significantly higher levels of CD80 on CD4+ T cells were detected in SLE patients with lupus nephritis compared to patients without nephritis (11.9 +/- 3.3% versus 4.0 +/- 0.7%; P < 0.005). There was an increased presence of CD134+ CD4+ cells in SLE patients with lupus nephritis (27.5 +/- 4.0% versus 15.5 +/- 1.3%; P < 0.005). CD80 and CD134 expression was significantly correlated with SLEDAI (r = 0.42, P = 0.03; r = 0.56, P < 0.005). Co-stimulatory molecules on CD4+ T cells are associated with renal disease and disease activity in patients with systemic lupus erythematosus.     

Oestrogen up‐regulates interleukin‐21 production by CD4+ T lymphocytes in patients with systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune disease in which abnormal immune responses are mediated by tissue‐binding autoantibodies and immune complex deposition. Because most SLE patients are women of child‐bearing age, oestrogen has been suggested to play an important role in SLE pathogenesis. One proposed role is to induce B‐cell activation, culminating in increased autoantibody production. Interleukin‐21 (IL‐21) has been shown to be crucial in the differentiation of activated B cells into plasma cells. We therefore hypothesized that oestrogen up‐regulates IL‐21 production and induces subsequent B‐cell activation in SLE patients. Peripheral blood was obtained from 22 SLE patients and 16 healthy controls. Expression levels of IL‐21 and its receptor in serum, peripheral blood mononuclear cells, and CD4⁺ T cells were higher in SLE patients than in healthy controls. Exposure of CD4⁺ T cells from SLE patients to 17β‐oestradiol led to a dose‐ and time‐dependent increase in IL‐21 expression, which was abolished in the presence of mitogen‐activated protein kinase (MAPK) (MAPK kinase, p38, Jun N‐terminal kinase) inhibitors. B cells from healthy controls showed increased antibody production when they were co‐cultured with oestrogen‐treated CD4⁺ T cells from SLE patients. Treatment with IL‐21 antibody abrogated the increased antibody production of the co‐culture systems. This study revealed the association between oestrogen and IL‐21 in SLE patients. Oestrogen up‐regulates IL‐21 expression of CD4⁺ T cells via MAPK‐dependent pathways in SLE patients, which in turn induces increased antibody production by B cells.     

Anti-interleukin-6 monoclonal antibody inhibits autoimmune responses in a murine model of systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune disease resulting from dysregulation of the immune system. Interleukin-6 (IL-6) is a multifunctional cytokine produced by macrophages, monocytes and T and B cells. It stimulates B-cell differentiation/maturation, immunoglobulin secretion, and T-cell functions. Elevated levels of IL-6 in serum, urine and renal glomeruli were detected in patients with active SLE and in murine models of SLE. Our study investigated the role of IL-6 in an SLE-like disease in New Zealand Black/White (NZB/W) F1 mice by administration of an anti-murine IL-6 monoclonal antibody (mAb). Intraperitoneal administration of the anti-IL-6 mAb suppressed the production of anti-dsDNA autoantibody. B-cell proliferation induced by anti-IgM and anti-CD40 was lower in the anti-IL-6 mAb-treated mice, ex vivo studies demonstrated that anti-IL-6 mAb treatment inhibited anti-dsDNA production. Anti-CD3-induced T-cell proliferation and mixed lymphocyte reactions were inhibited by anti-IL-6 mAb treatment, indicating a partial down-regulation of T cells. Histological analysis showed that treatment with anti-IL-6 mAb prevented the development of severe kidney disease. These results suggest that treatment with anti-IL-6 mAb has a beneficial effect on autoimmunity in murine SLE and that autoreactive B cells may be the primary target for anti-IL-6 mAb treatment; its effect on autoreactive T cells is also indicated.     

IL-18对系统性红斑狼疮患者淋巴细胞凋亡和P53蛋白表达的影响

目的　研究系统性红斑狼疮 (SLE)患者外周血淋巴细胞在体外IL 1 8刺激培养下细胞凋亡及P53蛋白表达情况。方法　AnnexinV联合PI染色定量法及免疫荧光染色法 ,分析了 44例SLE患者和 30例正常人外周淋巴细胞在体外IL 1 8刺激培养后凋亡发生率 ,凋亡相关基因P53蛋白的表达以及淋巴细胞凋亡发生与疾病活动性的相关性。结果　在IL 1 8刺激培养作用下 ,活动期SLE淋巴细胞凋亡发生率较正常人显著增高 (P <0 .0 1 ) ,而静止期则无明显变化 (P >0 .0 5)。P53蛋白表达在活动期SLE较正常人显著性下降 (P <0 .0 1 ) ,静止期无明显变化 (P >0 .0 5)。P53的表达与疾病活动指数SLEDAI之间有明显的相关性 (P <0 .0 1 )。结论　IL 1 8可引起SLE患者PBL凋亡率的增高 ,表明IL 1 8在体内凋亡或凋亡相关性免疫机制中起着一定的作用     

Atherosclerosis in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune rheumatic disease that has a late mortality phase owing mainly to cardiovascular manifestations. Atherosclerosis itself is characterized by inflammatory components, fulfilling the criteria of Witebsky and Rose for an autoimmune disease. SLE patients have increased risk for cardiovascular events, and these are the result of both atherosclerosis and thromboembolic events. Risk factors for atherosclerosis in SLE include “traditional” risk factors (mainly the Framingham risk factors), as well as disease-related factors including disease duration, steroid therapy, and renal disease, and inflammatory mechanisms that specifically contribute to enhanced atherosclerosis in SLE. These include specific antibodies to β2GPI; anticardiolipin antibodies; anti-oxidized low-density lipoprotein; and antibodies to heat shock proteins, complement activation, impaired ability to activate TGF-β1, and elevated levels of CRP. These findings stress the importance of surveillance and preventive strategies to control atherosclerosis in SLE.     

Expression of BAFF and BR3 in patients with systemic lupus erythematosus

The objective of this study was to examine the relationship between the expression ofB cell activating factor (BAFF) and BAFF receptor in patients with disease activityof systemic lupus erythematosus (SLE). Real-time RT-PCR was used to examine BAFF mRNAexpression in peripheral blood monocytes of active and stable SLE patients andhealthy controls. The percentage of BAFF receptor 3 (BR3) on B lymphocytes wasmeasured by flow cytometry. Soluble BAFF levels in serum were assayed by ELISA.Microalbumin levels were assayed by an automatic immune analysis machine. BAFF mRNAand soluble BAFF levels were highest in the active SLE group, followed by the stableSLE group, and controls (P<0.01). The percentage of BR3 on B lymphocytes wasdownregulated in the active SLE group compared with the stable SLE group and controls(P<0.01). BAFF mRNA levels and soluble BAFF levels were higher in patients whowere positive for proteinuria than in those who were negative (P<0.01). Thepercentage of BR3 on B lymphocytes was lower in patients who were positive forproteinuria than in those who were negative (P<0.01). The BAFF/BR3 axis may beover-activated in SLE patients. BAFF and BR3 levels may be useful parameters forevaluating treatment.     

原发性肾小球肾炎患者外周血IL—18 mRNA表达的研究

目的 探讨白细胞介素18（IL-18）在原发性肾小球肾炎（PGN）中的作用。方法 采用反转录多聚酶链反应（RT-PCR）及酶联免疫吸附法（ELISA）测定11例正常人及46例不同病程PGN患者外周血单核细胞（PBMC）IL-18 mRNA表达量及血浆中IL-18分泌水平。结果 肾功能代偿期原发性肾小球肾炎患者PBMC IL-18 mRNA表达量及血浆中IL-18的水平与正常对照组无统计学差异,而伴有肾功能损害的PGN患者则显著增高,且与肾功能损害相平行;直线相关分析显示;血浆内IL-18水平与Scr呈正相关、与Ccr呈负相关、与24h尿蛋白排泄量不相关。结论 外周血IL-18不参与PGN早期的发病过程,但当疾病进一步发展至伴有肾功能不全时,IL-18分泌水平相对升高可能在本病的进一步发展中发挥一定的作用。     

Immunosuppressive therapy modulates T lymphocyte gene expression in patients with systemic lupus erythematosus

To evaluate the T-cell large-scale differential gene expression in systemic lupus erythematosus (SLE) patients presenting with glomerulonephritis we studied SLE patients before and after immunosuppressive treatment. Large-scale gene expression of peripheral blood mononuclear T cells was evaluated using cDNA microarray nylon membranes containing 5184 cDNAs. Data were analysed using the SAM and Cluster and Treeview software. When untreated patients were compared to healthy individuals, 38 genes, most of them located on chromosomes 1, 3, 6, 17 and 19, were repressed, and when untreated patients were compared to treated ones, 154 genes, located on chromosomes 1, 6, 7, 12 and 17, were induced. In terms of biological function of coded proteins, the differentially expressed genes were associated with apoptosis, cell cycle, chromosomal scaffold, cytokine/chemokine, DNA repair/replication, Golgi/mitochondrial proteins, mRNA processing, signalling molecules and tumour suppressors. Two autoantigen genes related to RNA splicing (small nuclear riboprotein 70,000 MW-U1 SNR, and splicing factor 3a, 60,000 MW), and the tetranectin-plasminogen-binding protein were repressed. The Fc fragment of immunoglobulin G low affinity IIb, apoptotic protease activating factor-1, two subunits of cytochrome c, caspase 8, complement C5a, HLA-DRA, HLA-DQB1, transforming growth factor-beta receptor II, small nuclear ribonucleoprotein polypeptide N (Sm protein N) genes, heterogeneous nuclear riboprotein-C, and argininosuccinate lyase genes, among others, were induced. A total of 10 genes were repressed in untreated patients and induced in treated ones, among them tumour necrosis factor (ligand) superfamily member 9, tumour protein p53, mannosidase alpha class IA, and CD22. Although some of these differentially expressed genes are typically expressed in B cells, CD22 and CD32 have also been reported in T cells and may provide regulatory signals to B cells. Assessment of differential gene expression may provide hybridization signatures that may identify susceptibility, diagnostic and prognostic markers of SLE.