Novel Autoantibodies Related to Cell Death and DNA Repair Pathways in Systemic Lupus Erythematosus

Systemic lupus erythematosus(SLE) is a complex autoimmune syndrome characterized by various co-existing autoantibodies(auto Abs) in patients' blood.However,the full spectrum of auto Abs in SLE has not been comprehensively elucidated.In this study,a commercial platform bearing 9400 antigens(Proto Array) was used to identify auto Abs that were significantly elevated in the sera of SLE patients.By comparing the auto Ab profiles of SLE patients with those of healthy controls,we identified 437 Ig G and 1213 Ig M auto Abs that the expression levels were significantly increased in SLE(P 0.05).Use of the Proto Array platform uncovered over 300 novel auto Abs targeting a broad range of nuclear,cytoplasmic,and membrane antigens.Molecular interaction network analysis revealed that the antigens targeted by the auto Abs were most significantly enriched in cell death,cell cycle,and DNA repair pathways.A group of auto Abs associated with cell apoptosis and DNA repair function,including those targeting APEX1,AURKA,POLB,AGO1,HMGB1,IFIT5,MAPKAPK3,PADI4,RGS3,SRP19,UBE2 S,and VRK1,were further validated by ELISA and Western blot in a larger cohort.In addition,the levels of auto Abs against APEX1,HMGB1,VRK1,AURKA,PADI4,and SRP19 were positively correlated with the level of anti-ds DNA in SLE patients.Comprehensive auto Ab screening has identified novel auto Abs,which may shed light on potential pathogenic pathways leading to lupus.     

Spleen Tyrosine Kinase (Syk) Regulates Systemic Lupus Erythematosus (SLE) T Cell Signaling

Engagement of the CD3/T cell receptor complex in systemic lupus erythematosus (SLE) T cells involves Syk rather than the zeta-associated protein. Because Syk is being considered as a therapeutic target we asked whether Syk is central to the multiple aberrantly modulated molecules in SLE T cells. Using a gene expression array, we demonstrate that forced expression of Syk in normal T cells reproduces most of the aberrantly expressed molecules whereas silencing of Syk in SLE T cells normalizes the expression of most abnormally expressed molecules. Protein along with gene expression modulation for select molecules was confirmed. Specifically, levels of cytokine IL-21, cell surface receptor CD44, and intracellular molecules PP2A and OAS2 increased following Syk overexpression in normal T cells and decreased after Syk silencing in SLE T cells. Our results demonstrate that levels of Syk affect the expression of a number of enzymes, cytokines and receptors that play a key role in the development of disease pathogenesis in SLE and provide support for therapeutic targeting in SLE patients.     

Molecular Characterization of Circulating Plasma Cells in Patients with Active Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a generalized autoimmune disease characterized by abnormal B cell activation and the occurrence of increased frequencies of circulating plasma cells (PC). The molecular characteristics and nature of circulating PC and B cells in SLE have not been completely characterized. Microarray analysis of gene expression was used to characterize circulating PC in subjects with active SLE. Flow cytometry was used to sort PC and comparator B cell populations from active SLE blood, normal blood and normal tonsil. The gene expression profiles of the sorted B cell populations were then compared.SLE PC exhibited a similar gene expression signature as tonsil PC. The differences in gene expression between SLE PC and normal tonsil PC and tonsil plasmablasts (PB) suggest a mature Ig secreting cell phenotype in the former population. Despite this, SLE PC differed in expression of about half the genes from previously published gene expression profiles of normal bone marrow PC, indicating that these cells had not achieved a fully mature status. Abnormal expression of several genes, including CXCR4 and S1P₁, suggests a mechanism for the persistence of SLE PC in the circulation. All SLE B cell populations revealed an interferon (IFN) gene signature previously only reported in unseparated SLE peripheral blood mononuclear cells. These data indicate that SLE PC are a unique population of Ig secreting cells with a gene expression profile indicative of a mature, but not fully differentiated phenotype.     

Acute Renal Failure in Systemic Lupus Erythematosus

Acute anuric renal failure complicating systemic lupus erythematosus does not usually respond to treatment with corticosteroids and immunosuppressive agents. We describe four cases treated by dialysis, corticosteroids, and heparin in anticoagulant doses in which there was remarkable improvement in renal function after prolonged anuria. One patient died later from a gastric haemorrhage. The other three were alive and well 55, 54, and 30 months from the onset of anuria. In two cases a second renal biopsy showed a striking improvement in the lesions. Large doses of corticosteroid and heparin may be the best treatment in acute anuric lupus nephritis.     

ANCA与SLE临床表现的相关性及其意义

目的:探讨系统性红斑狼疮(Systemic Lupus Erythematosus,SLE)患者抗中性粒细胞胞浆抗体(Anti-neutrophil Cytoplasmic Antibodies,ANCA)与肾炎及其他临床表现和实验室检查的相关性及其意义.方法:采用前瞻性研究收集77例系统性红斑狼疮患者,用间接免疫荧光法(IIF)检测患者血清ANCA、ELISA法检测ANCA抗原,检测其他免疫学指标如抗核抗体、抗dsDNA抗体等.结果:77例SLE患者中ANCA阳性28(36.4%)例,ANCA阳性组浆膜炎、肾损害、神经精神症状、皮肤血管炎、抗dsDNA抗体阳性、抗Sm抗体阳性、补体下降以及血清IgG升高的发生率明显高于阴性组(P＜0.05).52例LN患者中,25例(48.1%)ANCA阳性,其中P-ANCA阳性者22例(88%).3例(12%)为a-ANCA均出现在RPGN,无一例出现c-ANCA.非LN组25例患者中,仅3例(12%)p-ANCA阳性,且均为抗-MPO.正常对照组无一例ANCA阳性.77例SLE患者中,14例(18.2%)为抗-MPO;13例(16.9%)为抗LF,且只见于DPGN、FPGN和RPGN伴有新月体形成者;10例(13%)为抗-CG,但在非狼疮肾炎患者未检测到抗-LF及抗-CG.在各种临床表现中,抗-MPO与肾脏和皮肤表现有关;而抗-LF与肾脏、关节炎及浆膜炎有关;抗-CG可见于各种临床表现.结论:ANCA可作为评价SLE疾病及鉴别血管炎和狼疮肾炎的一个重要指标.     

BLyS与系统性红斑狼疮

淋巴细胞刺激因子BLys是肿瘤坏死因子家族的新成员,对于B细胞的发育增殖具有重要的作用。狼疮小鼠及系统性狼疮患体内BLys水平增高,阻断BLys的作用可以使使狼疮小鼠的病情缓解,存活时间延长。因此,BLys拮抗剂可能对系统性红斑狼疮患具有治疗作用。     

Systemic Lupus Erythematosus associated with Haemobartonella-like Organisms

SYSTEMIC lupus erythematosus (SLE) is a severe disease affecting thousands of human beings each year in the United States¹. Its aetiology is not known, although infections and autoimmune processes have been suggested. Immunological mechanisms have been associated with the pathogenesis of anaemia in certain haemotropic infections of domestic animals² caused by the haemobartonella group. This communication describes the possible association between a haemo-bartonella-like agent and SLE.     

Animal Models of Human Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a human autoimmune disease of unknown etiology. Clinical, serologic, immunologic, and pathologic findings are highly variable in different patients and at different times in the same patient. Murine and canine animal models of SLE have been found with clinicopathologic abnormalities resembling those observed in humans. Each animal model has unique characteristics; taken together they reflect the spectrum of disease in human SLE.Investigations in the animals have suggested that genetic, hormonal, immunologic, viral, and other environmental factors contribute to and modify the expression of disease. Where analogous studies are available for humans, the same factors have been found to modify disease expression in a similar fashion. Together, these studies have helped to clarify the multifactorial basis for SLE.The best characterized abnormalities are immunologic. These include excessive B cell function with the formation of large amounts of autoantibodies, and T cell abnormalities which include defects in T cell regulatory function as well as certain T cell effector functions.The animal models of SLE also serve as convenient test subjects for newer therapeutic modalities. It is hoped that further study of the animal models will provide a more rational approach to therapeutic modulation of disease in humans with SLE.