The pentapeptide PLNPK inhibits systemic lupus erythematosus-associated renal damage

Objective

This study aimed to observe the therapeutic effect of pentapeptide PLNPK on systemic lupus erythematosus (SLE) in mice, and to study the inhibitory effect of PLNPK on activation of T cells in vivo.

Methods

Murine SLE-like chronic graft-versus-host disease (cGVHD) was induced. After treatment with PLNPK (100, 200, 400 μg/kg per day) for 70 days, serum blood urea nitrogen, creatine, total cholesterol, triglyeride and albumin were tested, and serum levels of anti-dsDNA and anti-histone antibodies were detected by ELISA. The pathological damage and IgG deposition in the kidney were identified. Concanavalin A (ConA)-induced T lymphocyte proliferation in SLE mice was also tested.

Results

PLNPK can reduce serum blood urea nitrogen, creatine, total cholesterol, triglyeride, and elevate serum albumin, and reduce levels of anti-dsDNA and anti-histone antibodies in the murine SLE model. Pathological damage and IgG deposition in the kidney were reduced in the PLNPK-treated group. PLNPK inhibited T lymphocyte infiltration in kidney tissues and ConA-induced T lymphocyte proliferation in SLE mice.

Conclusion

Our results demonstrate that PLNPK can suppress T cell function and reduce the production of autoantibodies, and may be a feasible and effective therapy in the SLE model.     

Distinct cytokine profile in juvenile systemic lupus erythematosus-associated macrophage activation syndrome

Macrophage activation syndrome (MAS) has been observed in patients with systemic lupus erythematosus (SLE). Recognition of MAS in patients with SLE may be particularly challenging because it may mimic the clinical features of the underlying disease or be confused with an infectious complication. Massive hypercytokinemia is strongly associated with the pathogenesis of systemic lupus erythematosus-associated macrophage activation syndrome (SLE–MAS) but the pathogenesis and kinetics of cytokine release in SLE–MAS patients is not well studied. We present a case of SLE–MAS. The patient showed the distinct cytokine profile of SLE–MAS compared to systemic juvenile idiopathic arthritis associated MAS and Epstein–Barr virus-induced hemophagocytic lymphohistiocytosis. The observed TNF-α dominant increase appears to be characteristic of SLE–MAS. IgM type antilymphocyte antibody (ALAB) was detected on the surface of lymphocytes during the acute phase and disappeared when the patient was in remission. The patient had a heterozygous P369S-R408Q mutation in the MEFV gene. Our results suggest that ALAB and a MEFV mutation might play important roles in the pathogenesis of SLE–MAS. Furthermore, the cytokine profile of SLE–MAS differs from that of S-JIA–MAS: the TNF-α dominant increase appears to be characteristic.     

Properdin levels in systemic lupus erythematosus and membranoproleferative glomerulonephritis

The participation of the classical complement pathway, of the properdin system and of the C3b amplification system, is studied in forty-six patients suffering from systemic lupus erythematosus (SLE) and in forty-two patients with membrano-proliferative glomerulonephritis (MPGN). In SLE the decrease of C3 is associated with a decrease of the early acting complement components as well as a decrease of C3PA and properdin. The decrease of C3PA is closely related to the C3 level. This pattern correlates well with a major involvement of the classical complement pathway and of the C3b amplification system. In MPGN the decrease of C3 is associated with normal values of early acting complement components and with a decrease of C3PA and properdin levels. There is no clear relationship between C3PA levels and C3 levels, but C3 levels are closely related to the properdin levels as seen by regression analysis. This pattern is suggestive of a major involvement of the properdin system in MPGN.     

Renal biopsy in patients with systemic lupus erythematosus: Not just lupus glomerulonephritis!

Kidney biopsy is a mainstay in the diagnosis and management of renal disease in patients with systemic lupus erythematosus. Though biopsies from patients with lupus typically show various forms of immune complex glomerulonephritis, other pathologies are occasionally encountered, including unusual lupus-related nephropathies, other forms of autoimmune disease, and occasional renal disorders without any direct connection with lupus or autoimmunity. Electron microscopy is a powerful tool for detecting and classifying these unusual conditions, which frequently have important therapeutic and prognostic implications.     

Presence of hepatitis-associated antigen in systemic lupus erythematosus

Presence of hepatitis-associated antigen (HAA) was investigated in 504 sera from 116 patients with SLE and was found in 41% of them.

HAA was present in at least one serum in 75% of the patients but there were variations in presence and titres in the same patient at different times.

Except for a tendency of HAA to appear or rise in titre with lupusi nactivation following corticosteroid or immunosuppresive therapy, there was no correlation between its presence and disease activity, specific organ involvement, antinuclear antibodies or immunoglobulin levels.

All but one of twelve lupus patients with recurrent bacterial infections had HAA at high titres. HAA appeared in the serum of a patient upon development of IgA deficiency.

HAA antigenaemia in systemic lupus erythematosus seems a consequence rather than a cause of the immunological derangement in this disease.

     

系统性红斑狼疮患者外周血单核细胞PD L2分子的表达及其临床意义

目的：分析系统性红斑狼疮患者外周血单核细胞PD-L2分子的表达及其与疾病活动程度的相关性。方法：收集26例系统性红斑狼疮患者及38例健康对照组外周血,Ficoll分离单个核细胞后,TRIZOL抽提总RNA,定量PCR分析PD-L2基因的表达,流式细胞仪检测CD14、PD-L2分子的表达。统计学分析其相关性及与疾病活动程度之间的关联。结果：定量PCR结果提示系统性红斑狼疮患者外周血单核细胞PD-L2基因表达高于健康对照组(P<0.05),流式发现单核细胞上PD-L2高表达(P<0.05),且活动期患者表达高于稳定期,并且与疾病的评分(SLEDAI)呈正相关(P<0.05)。结论：免疫分子PD-L2可能参与系统性红斑狼疮疾病的进程并可能成为疾病预防及治疗的潜在分子。     

Serial complement component alterations in acute glomerulonephritis and systemic lupus erythematosus

Serial determinations of whole serum complement (C') and absolute weight concentrations of the C'1q (11S) portion of the first and the third (C'3), fourth (C'4) and fifth (C'5) components of human complement were carried out in patients with post-streptococcal acute glomerulonephritis, systemic lupus erythematosus and other types of nephritis including Henoch–Schönlein (anaphylactoid purpura), Goodpasture's syndrome and chronic glomerulonephritis.

Total haemolytic complement was decreased in patients with acute glomerulonephritis and active systemic lupus erythematosus, but distinctly different component patterns occurred which were characteristic for each disease. In acute glomerulonephritis the concentration of C'1q was normal and C'4 was decreased only during the initial phase of illness. More prolonged depressions of C'3 and C'5 occurred which paralleled the whole complement titres. In contrast subjects with active systemic lupus erythematosus had normal C'5 concentrations and decreases in C'1q, C'4 and C'3 with prolonged depression of C'4 being the most consistent finding. Recent evidence has suggested that both post-streptococcal acute glomerulonephritis and systemic lupus erythematosus share a similar immunopathogenic mechanism involving the deposition in renal glomeruli of immune complexes formed by non-glomerular antigen and specific antibody. If so, the physico-chemical characteristics of the immune complexes differ enough to cause distinctive component alterations. Entirely normal whole complement and component levels were observed in patients with other types of nephritis.

In post-streptococcal acute glomerulonephritis the early return to normal of fourth component concentrations may be a favourable prognostic sign while the persistent depression of this component in systemic lupus erythematosus may be an indication of occult disease activity.

     

Immune complex clearance by monocytes and macrophages in systemic lupus erythematosus

During the last 30 years more than 700 patients with systemic lupus erythematosus (SLE) have been treated in our department with their data analyzed. Here we focus on circulating immune complex (CIC) and its clearance. We demonstrated, microscopically, that the uptake of IgG sensitized erythrocytes (EA), via monocytes (Mo) of SLE patients, was elevated and correlated with the high CIC content. The in Vivo clearance of sensitized autolog E, and the in vitro degradation rate of soluble IC by Mo of SLE patients were decreased. This discrepancy could be explained by the molecular heterogeneity of FcgammaR being recognized lately. The high FcgammaRI expression and the low FcgammaRII and FcgammaRIII expression were detected by monoclonal antibodies (mAb) on Mo in SLE. The EA bound mostly to FcgammaRI, FcgammaRII and FcgammaRIII have a role in phagocytosis. The decreased receptor expression and function correlated with the disease activity and renal involvement. The shedding of receptors may cause a decrease on Mo surface, with the soluble FcRII and FcgammaRIII levels being elevated in serum of SLE patients. The mannose binding receptors, which play a role in the phagocytosis of apoptotic cells in SLE, were also decreased on Mo of SLE patients.     

Platelet-aggregating immune complexes and intraplatelet serotonin in idiopathic glomerulonephritis and systemic lupus.

Immune complex-like material was studied using the platelet-aggregation test (PAT) in 114 patients with idiopathic glomerulonephritis and 55 patients with SLE nephritis, and the results obtained compared with Raji cell and Clq-binding assays. The platelet-aggregating material was not thrombin, and eluted from Sepharose CL/6B columns with a molecular weight of greater than 500,000 daltons. Sera from 17 of 55 patients with SLE nephritis were positive in all three assays, 50/55 in at least one assay. No circulating material was detected by the Raji cell assay in idiopathic glomerulonephritis patients, but both the Clq-binding and PAT assays detected material in patients with acute post-infectious nephritis and mesangiocapillary glomerulonephritis. Patients with membranous nephropathy and Henoch-Schönlein purpura were positive in the PAT, although generally negative in the other assays of immune complexes. The amount of platelet-aggregating material (PAM) found in the sera of patients with both idiopathic glomerulonephritis and SLE nephritis correlated closely with the depletion of intraplatelet serotonin, suggesting that this material is a major mechanism of in vivo platelet activation in these patients.     

Relationships between antibodies to native DNA and glomerulonephritis in systemic lupus erythematosus.

Anti-native DNA antibodies have been evaluated in forty-six lupus patients' sera for antigen-binding capacity, affinity and precipitating activity. Diffuse proliferative glomerulonephritis was significantly correlated with the presence of high serum level of free anti-native DNA antibodies. Weak affinities were more often found in patients with than without glomerular changes but several patients had high-affinity anti-DNA antibodies and severe glomerulonephritis. No correlation was found between anti-DNA antibody-precipitating activity and renal lesions.     

Measurement and significance of 3-nitrotyrosine in systemic lupus erythematosus

Nitration of free and protein associated tyrosine represents, in vivo, a mechanism that can severely compromise the cell function. The detection of 3-nitrotyrosine (3-NT) in pathological tissues is suggestive of the occurrence of nitrating pathways and has been identified as a marker of inflammation and a stable end product of increased reactive nitrogen intermediate production. Protein nitration occurs in many disease conditions including systemic lupus erythematosus (SLE). In this study we show that the level of both free and protein bound 3-NT, which is produced by reactive nitrogen species (RNS)-dependent oxidative damage, is elevated in patients with SLE and that there is a possible role of RNS-modified epitopes in the aetiology of the disease. Commercially available poly L-tyrosine was exposed to nitrating species, inducing nitration in tyrosine residues. Immunoglobulin-G (IgG) purified on Protein-A-Sepharose matrix from 24 SLE patients was studied for their recognition of native and nitrated poly L-tyrosine by direct binding and competition enzyme-linked immunosorbent assay (ELISA). The formation of immune complex between SLE IgG and nitrated poly L-tyrosine was visualized by gel retardation assay. Free 3-NT in patients' sera was detected and quantitated by high performance liquid chromatography whereas protein-bound 3-NT was analysed by Western blotting and the concentration was calculated by sandwich ELISA. The concentration of free 3-NT was found to be 1.4 +/- 0.09 microm whereas the concentration of protein bound 3-NT was 96.52 +/- 21.12 microm nitrated bovine serum albumin equivalents/mg protein, which was significantly higher when compared with healthy controls. Elevated level of 3-NT was observed in SLE patients using two different techniques, when compared with healthy subjects confirms the overproduction of RNS in the pathogenesis of human SLE.     

系统性红斑狼疮患者血清泌乳素水平的检测及其临床意义

目的：探讨系统性红斑狼疮(SLE)患者血清泌乳素(PRL)水平检测的临床意义。方法：应用免疫放射量度分析法测定了75例SEE患者与25例健康人血清PRL水平。结果：SLE患者血清PRL水平明显高于正常对照组，且活动期升高更明显；高泌乳素血症(HPRL)发生率为40％，伴HPRL的患者肾损害发生率明显高于血清PRL正常者；血清PRL水平与SLEDM评分、抗ds-DNA抗体滴度倒数呈正相关，与C3呈负相关。结论：SLE患者血清PRL水平升高与病情活动相关，其检测可作为监测狼疮病情活动性的指标之一；血清PRL水平升高与肾脏损害相关，提示PRL可能在SLE肾损害中起作用。     

白介素-1 受体相关激酶-M 在系统性红斑狼疮患者单核细胞中的表达及与临床的相关性

目的:研究白介素-1受体相关激酶-M(Interleukin-1 receptor associated kinases M,IRAK-M)在系统性红斑狼疮(Systemic lupus erythematosus,SLE)患者单核细胞中的表达情况及与临床的相关性。方法:采用实时荧光定量PCR技术,检测SLE组和健康对照组单核细胞中IRAK-M的mRNA表达量;采用酶联免疫吸附试验法检测抗双链DNA抗体(ds DNA)和抗单链DNA抗体(ss DNA);采用动态免疫散射比浊法测定补体3(C3)、补体4(C4)和C-反应蛋白(CRP);采用魏氏法测定红细胞沉降率(ESR)。同时,使用Pearson或Spearman分析IRAK-M与SLEDAI评分、ds DNA、ss DNA、C3、C4、CRP和ESR的相关性。结果:1SLE组IRAK-M的mRNA表达量明显低于健康对照组(P0.05),活动期SLE组IRAK-M的mRNA表达量明显低于稳定期SLE组(P0.05)。2SLE组ds DNA、ss DNA、CRP和ESR水平明显高于健康对照组(P0.05),C3和C4水平明显低于健康对照组(P0.05);而且,活动期SLE组ds DNA、ss DNA、CRP和ESR水平明显高于稳定期SLE组(P0.05),C3和C4水平明显低于稳定期SLE组(P0.05)。3相关分析显示:IRAK-M的mRNA表达量与C3成正相关(P0.05),与SLEDAI评分、ds DNA、CRP、ESR呈负相关(P0.05),与ss DNA和C4无相关性(P0.05)。结论:IRAK-M在SLE发病机制中起着重要的作用;定量检测IRAK-M的mRNA表达量可监测SLE疾病活动度和判断预后。同时,对SLE患者ds DNA、ss DNA、CRP、C3、C4和ESR水平的常规检测和定期监测是非常必要的。     

Absence of interferons-alpha and -gamma in renal lesions of systemic lupus erythematosus and membranous glomerulonephritis

Frozen kidney biopsy sections from nine patients with systemic lupus erythematosus (SLE) as well as many other renal diseases, including IgA nephropathy, membranous nephritis, and minimal change nephrotic syndrome, were negative for interferons -alpha and -gamma by immunofluorescence. Lupus patients studied included several subjects with marked serum elevations of interferon activity as well as others with low or negative serum interferon levels. Isolated glomerular eluates prepared from normal and SLE kidneys showed no functional interferon activity by virus plaque inhibition assay. Components of normal as well as SLE serum showed no direct binding to interferon -alpha or -gamma by ELISA assays.     

Circulating colony-forming units of granulocytes and monocytes/macrophages in systemic lupus erythematosus.

In systemic lupus erythematosus (SLE) patients, in vitro bone marrow (BM) colony-forming units of granulocytes and monocytes/macrophages (CFU-GM) are decreased, suggesting that granulomonopoietic failure may play an important role in the mechanism of peripheral blood (PB) depletion of neutrophils and monocytes. No information concerning CFU-GM in PB of patients with SLE is available. The present study was undertaken in order to determine whether SLE itself and the inactive or active stage of disease would modify the number of GFU-GM in PB samples from 20 treatment-free SLE women, 12 inactive and eight active. CFU-GM growth was significantly decreased in both inactive (P = 0.018) and active (P = 0.008) SLE patients as compared with controls (n = 8). The difference in CFU-GM growth between SLE groups was not significant. These results indicate that the number of circulating CFU-GM is significantly reduced in patients with SLE regardless of disease activity or remission.     

Presence of lupus-type anticoagulant, in systemic lupus erythematosus and other clinical entities

The frequency of "Lupus anticoagulant" (LA), was studied in 51 patients with systemic lupus erythematosus (SLE), 15 patients with chronic immune thrombocytopenic purpura (ITP) and 3 other patients with prolonged partial thromboplastin time (PTT), two of which had suffered episodes of CVA, and the other had a diagnosis of Paroxysmal Nocturnal Hemoglobinuria. Lupus anticoagulant was determined in each patient by the plasma recalcification time and the Russell's viper venom clotting time. Eight patients with SLE, (15.6%) 6 with chronic ITP (40%) and the three patients with prolonged PTT were positive for LA. All patients with LA were female, whose ages ranged from 19 to 59 years, and all except two patients were under steroid therapy. Thrombocytopenia was the most frequent manifestation in the patients with LA, followed by recurrent fetal death and thrombosis. Only the patients with ITP had hemorrhagic complications and one of them also had CVA in one occasion. The immunosupressory therapy may have played a role in diminishing the frequency of LA in the patients studied.     

Characterization of a novel T-cell lymphoma cell line established from a patient with systemic lupus erythematosus-associated lymphoma.

A malignant lymphoma developed in a 46-year-old male patient who had had systemic lupus erythematosus (SLE) for 18 years. The lymphoma was at disease stage IV at initial examination, and the patient died shortly thereafter. The lymphoma cells were cultured in vitro, and a continuous cell line, named SMZ-1, was established. The SMZ-1 cells, as well as the parental lymphoma cells, were of helper/inducer T-cell immunophenotype; they were positive for CD2, CD3, and CD4 antigens, and negative for CD8. Expression of CD5 and CD7 antigens was observed in a small percentage of the cells. The activation markers identified by antibodies against CD25, CD71, and HLA-DR antigens were positive. Cytogenetic analysis revealed that the SMZ-1 cells had a characteristic translocation between chromosomes 6 and 14 [t(6;14)(p21.1;q24)]. Southern blot analysis of DNA extracted from the cells demonstrated clonal rearrangement of the T cell receptor beta-chain gene. Integration of the human T-cell lymphotrophic virus type I (HTLV-I) genome was negative. The SMZ-1 cell lines should thus provide a useful model for characterization of peripheral T-cell lymphomas.     

Hereditary C2 deficiency and systemic lupus erythematosus associated with severe glomerulonephritis.

Although an unusually high incidence of immunological diseases has been described in patients with hereditary C2 deficiency, the severity of these illnesses has been relatively mild, suggesting that blocking complement activation beyond C4 may protect against significant complement-mediated inflammation. This report describes studies in a C2-deficient patient with severe systemic lupus erythematosus (SLE) and diffuse proliferative glomerulonephritis. An immunopathological study of the kidney revealed the deposition of properdin, properdin factor B, C3 and C5 in a pattern similar to immunoglobulin G deposits. Serum properdin and properdin factor B levels were low at various times during the patient's course. In vitro complement fixation studies showed C3 fixation by glomerular deposits could occur via the alternative pathway. Studies of the immune deposits in the patients' skin revealed similar results. These studies suggest that inflammation may be effectively mediated via the alternative complement pathway in the C2 deficiency-lupus syndrome.