Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0024141 (systemic lupus erythematosus)
 44,322 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Complement-derived peptides capable of activating neutrophils appear in plasma during flares of systemic lupus erythematosus (SLE). One possible consequence of such activation is an increased expression of the surface adhesion promoting heterodimer gp165/95 (the complement receptor CR3). The quantity of gp165/95 was measured by indirect immunofluorescence using a monoclonal antibody of the CD11b group. Mol, directed to the alpha chain. Eighty-three percent of 26 patients with SLE expressed gp165/95 on their neutrophil surface to a greater extent than normals. The highest levels of surface gp165/95 were found in patients with the most severe disease, who also had the highest levels of the circulating anaphylatoxin C3a (mean = 560 ng/ml versus 147 ng/ml in controls). There was a negative correlation between expression of gp165/95 and absolute neutrophil count. Five individuals followed serially demonstrated an increase in surface gp165/95 during disease flares which returned to normal with clinical improvement. These data support the hypothesis that the neutrophils of patients with active SLE recruit increased numbers of gp165/95 molecules to their surface in respose to complement activation; these activated neutrophils bearing increased numbers of adhesion promoting gp165/95 may contribute to endothelial injury in SLE.
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PMID:Surface expression of Gp 165/95, the complement receptor CR3, as a marker of disease activity in systemic Lupus erythematosus. 296 92

Previous studies have shown that neutrophils in the circulation of patients with active systemic lupus erythematosus (SLE) are activated as judged by their increased surface expression of the beta 2-integrin CD11b/CD18. Since activation of neutrophils leads to altered expression of another adhesion molecule, L-selectin (LS), we examined neutrophils from patients with SLE for changes in the expression of CD11b/CD18 and LS by cytofluorographic analysis of immunofluorescent-labeled cells. Overall there was no difference between surface expression of CD11b/CD18 on neutrophils from SLE patients or controls [mean fluorescence 225 +/- 26 vs 225 +/- 13 relative fluorescence units (RFU), respectively]. However, as previously reported, neutrophils from patients with more active disease (activity score > or = 3, UCH Middlesex activity score) expressed greater CD11b/CD18 than neutrophils from controls (319 +/- 40 RFU, P < 0.03, n = 9) or from patients with less active disease (193 +/- 10 RFU, P < 0.006). Indeed, CD11b/CD18 expression correlated directly with disease activity (r = 0.54, P < 0.02). Stimulation of neutrophils ex vivo with the chemoattractant N-formyl-methionyl-leucyl-phenylalanine (100 nM) induced up-regulation of CD11b/CD18 in cells from both SLE patients and controls (205 +/- 12% vs 239 +/- 15% of basal, respectively), but neutrophils from the most active patients (score > or = 3) increased CD11b/CD18 expression less than controls (175 +/- 12% of basal, P < 0.003, n = 9). The magnitude of the stimulated increment in expression of CD11b/CD18 on neutrophils correlated inversely with SLE activity (r = -0.64, P < 0.003, n = 20). Surprisingly, we observed no change in LS expression on neutrophils from SLE patients compared to controls (143 +/- 14 vs 141 +/- 16 RFU, respectively) even in patients with the highest activity indices (154 +/- 21 RFU). In contrast to CD11b/CD18, there was no correlation between LS expression and disease activity (r = 0.12, P = NS). Stimulation of neutrophils reduced the expression of LS similarly in both controls and SLE patients (67 +/- 3% vs 58 +/- 4% reduction, respectively) and did not correlate with disease activity (r = 0.07, P = NS, n = 20). These results show, for the first time, that changes in CD11b/CD18 expression do not correlate with LS expression on neutrophils from patients with active SLE.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Intravascular neutrophil activation in systemic lupus erythematosus (SLE): dissociation between increased expression of CD11b/CD18 and diminished expression of L-selectin on neutrophils from patients with active SLE. 751 35

Flaxseed is rich in alpha-linolenic acid (alpha-LA) which has anti-atherogenic properties, and lignans which are platelet activating factor (PAF)-receptor antagonists. These constituents of flaxseed, and its beneficial effects in the MRL/lpr lupus mouse prompted us to perform this dosing study in lupus nephritis patients. Nine patients were enrolled, eight of whom completed the study. After the baseline studies, patients were given 15, 30, and 45 g of flaxseed/day sequentially at four week intervals, followed by a five-week washout period. Compliance, disease activity, blood pressure, plasma lipids, rheology, PAF-induced platelet aggregation, renal function, and serum immunology were assessed. Flaxseed-sachet count and a significant increase of serum alpha-LA indicated good compliance for 15 and 30 g doses. Total and LDL cholesterol, and blood viscosity were significantly reduced with 30 g and to a lesser extent 45 g doses. PAF-induced platelet aggregation was inhibited by all doses. There was a significant decline in serum creatinine with 30 and 45 g, and a concomitant increase in creatinine clearance with increasing flaxseed dose. Proteinuria was reduced with 30 g and to a lesser extent with 45 g of flaxseed. Complement C3 was significantly elevated by all three doses. CD11b expression on neutrophils, a measure of C3bi receptors, was significantly reduced with the 30 g dose. In conclusion, 30 g flaxseed/day was well tolerated and conferred benefit in terms of renal function as well as inflammatory and atherogenic mechanisms important in the pathogenesis of lupus nephritis.
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PMID:Flaxseed: a potential treatment for lupus nephritis. 756 15

The expression of Fc gamma RI, Fc gamma RII, and Fc gamma RIII (the IgG receptors CD64, CD32, CD16) as well as CR3 (the C3bi receptor, CD11b) on monocytes in the blood of patients with systemic lupus erythematosus (SLE) was investigated. The relationship between the receptor expression and the serum immune complex (IC) concentration was analysed. The decrease in mean fluorescence intensity (FI) of the Fc gamma RII of patients' monocytes stained by specific monoclonal antibodies (MoAb IV3) was very close to statistical significance (P = 0.052). The expression (FI) of CR3 (using MoAb OKM1) on monocytes of patients was also decreased, but not significantly. The detected decrease of Fc gamma RII and CR3 was inversely correlated with the high circulating immune complex level in patients' sera. At the same time, Fc gamma RI expression on SLE monocytes (using MoAb 32) was significantly elevated and this change was in parallel with the serum IC concentration.
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PMID:Correlations of monocyte phagocytic receptor expressions with serum immune complex level in systemic lupus erythematosus. 797 54

The MRL/lpr mouse develops, after approximately 8 weeks of age, a severe autoimmune syndrome with many features resembling human systemic lupus erythematosus, including autoantibodies against DNA and basement membranes resulting in immune complexes, vasculitis, and multiorgan disease. While this murine model of lupus has been used for the identification of therapeutics with potential efficacy in human autoimmune disease, the long-term impact of chronic immunosuppressive therapy on macrophage function in this paradigm is not understood. To this end, MRL/lpr mice were treated prophylactically with dexamethasone at 0.01, 0.1, and 1 mg/kg of body weight for 20 weeks or were allowed to develop autoimmune disease and, at 15 weeks of age, treated therapeutically with 1-mg/kg dexamethasone for 8 additional weeks. Analysis of surface antigens on resident peritoneal macrophages demonstrated a progressive loss in class I expression with a concomitant increase in Fc receptor expression. Neither phagocytosis nor CD11b expression was modulated with chronic steroid treatment. Furthermore, dexamethasone treatment was associated with a reduction in anti-DNA antibodies and total immunoglobulin G and yet an elevation in serum cholesterol due to an increase in high-density lipoproteins. Therefore, the MRL/lpr mouse serves not only as a small-animal model of autoimmune disease but also as one in which the negative and positive sequelae associated with chronic immunosuppression can be further understood.
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PMID:Chronic administration of dexamethasone results in Fc receptor up-regulation and inhibition of class I antigen expression on macrophages from MRL/lpr autoimmune mice. 930 7

Sexual dimorphism exists in the immune response. Both humoral and cell-mediated immunity are more active in females than in males, and steroid gonadal hormones may play an important role in regulating this response. We have documented gender differences in several aspects of neutrophil and macrophage functions elicited by lipopolysaccharide (LPS) (endotoxin) treatment and/or acute ethanol intoxication. In LPS-treated female rats, circulating neutrophils and alveolar macrophages are resistant to the deleterious effects of surgery and anesthesia on phagocytosis observed in male rats. The generation of cytokine-induced neutrophil chemoattractant (CINC) by hepatocytes and Kupffer cells of LPS-treated rats, as well as TNF-alpha secretion by Kupffer cells and alveolar macrophages of acutely ethanol intoxicated rats are also gender dependent. The effects of alcohol on the immune response are expressed differently in males and females. In LPS plus ethanol-treated rats gender differences were noted in terms of adhesion molecule (CD11b/c) expression on circulating neutrophils, and cytoskeletal reorganization in blood-recruited neutrophils and Kupffer cells. Nitric oxide (NO) plays an important role in inflammatory processes. We found gender differences in NO production by alveolar macrophages of LPS-treated rats; this difference was abrogated by ethanol treatment. LPS tolerance and ethanol treatment modulate hepatic NO production in rats in a cell- and gender-dependent fashion, which may exert a protective influence against oxidative injury in the female liver.
Lupus 1999
PMID:Gender differences in some host defense mechanisms. 1045 17

Immune imbalance in SLE increases the susceptibility to infectious diseases. The aim of this study was to analyze several mechanisms related to non-specific immunity in this autoimmune disorder. We studied in vivo CD11b expression, phagocytosis, and chemotaxis in polymorphonuclear cells (PMN) from SLE patients. All tests were also performed under hrIL-8 stimulating conditions and analyzed by flow cytometry. Intracellular leucocyte (monocytes and PMN) enzyme activity was evaluated using specific substrates for cathepsin B and D, collagenase, and oxidative burst by flow cytoenzymology. An exaggerated in vivo CD11b expression was observed on PMN from SLE patients without noticeably in vitro effect upon hrIL-8. Similarly both, phagocytosis and chemotaxis were diminished and showed no response to hrIL-8 stimulation. The opposite was found in PMN from controls. Intracellular enzyme activity was comparable between groups as far as cathepsin B and D are concerned. A tendency of decreased oxidative-burst induction was noted in monocytes and PMN from SLE patients, whereas collagenase activity was found clearly increased in both leucocyte subpopulations. Our results may represent a deficient ability of the innate immune mechanisms for the clearance of infectious agents, immune complexes, satisfactory resolution of inflammatory processes and tissue repair in SLE.
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PMID:Innate immune mechanisms in the pathogenesis of systemic lupus erythematosus (SLE). 1141 Feb 51

We recently demonstrated that IgG from patients with systemic lupus erythematosus (SLE) in combination with U937 cells made apoptotic by UV-irradiation, can induce interferon-alpha (IFN-alpha) production in normal peripheral blood mononuclear cells (PBMC). In the present study we show by flow cytometry that the actual IFN-alpha producing cells (IPC) among PBMC had the same phenotype (HLA-DR+, CD4+, CD11b-, CD11c-, CD14-, CD19-, CD32-, CD36+, CD40+, CD45RA+, CD68+, CD83+, CD86-, IL-3R+ and IL-10R-) and low frequency (approximately 2/10(4)PBMC) as the IPC activated by Herpes simplex virus type I. Consequently, these cells correspond to the natural IPC, also described as type 2 precursor dendritic cells. We also demonstrated that cytokines of possible importance in the pathogenesis in SLE had effects on the IFN-alpha production. Specifically, the IFN-alpha production was strongly increased by the type I IFNs, IFN-alpha and -beta, but markedly inhibited by IL-10 and also to some extent by TFN-alpha. In contrast, the cytokines IFN-gamma, IL-6, TGF-beta and GM-CSF had no clear effects. No production of IL-10 was detected in PBMC stimulated by apoptotic U937 cells and SLE IgG. These results may explain the cause of the ongoing IFN-alpha production in SLE patients and its relation to the autoimmune process.
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PMID:Activation of natural interferon-alpha producing cells by apoptotic U937 cells combined with lupus IgG and its regulation by cytokines. 1148 39

Deficiency of complement in humans and mice is associated with the development of lupus and with abnormal repair of inflammatory and immune complex-mediated tissue injury. Here we ask whether similar defects in the resolution of inflammation are found in mice prone to spontaneous lupus. We compared the response to an i.p. injection of thioglycolate between two lupus-prone strains (MRL/Mp and NZB/W) and two non lupus-prone strains of mice (C57BL/6 and BALB/c). In all four strains the influx of polymorphonuclear neutrophils (PMN) was similar. However, by 96 h clearance of PMN in the control strains was complete, whereas in the autoimmune-prone strains PMN were still detectable. The number of mononuclear cells recruited was markedly reduced in the lupus-prone strains compared with the controls, and their phenotype was different. The lupus-prone strains had significantly fewer elicited macrophages that were CD11b-high and Ly6C-negative. In lupus-prone mice at 24 h there was a significantly increased number of apoptotic PMN free in the peritoneum, accompanied by a reduced percentage of macrophages containing apoptotic bodies, suggesting a defect in their uptake. An impaired ability of resident peritoneal macrophages from lupus-prone mice to engulf apoptotic cells was demonstrated by in vivo and in vitro cell clearance assays. These observations indicate that lupus-prone strains have an abnormal inflammatory response to thioglycolate and an intrinsic impairment in apoptotic cell uptake. These findings have implications for the initiation of autoimmunity, as lupus autoantigens are expressed on dying cells, and impaired disposal of these could enhance the development of autoimmunity.
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PMID:Lupus-prone mice have an abnormal response to thioglycolate and an impaired clearance of apoptotic cells. 1262 81

Type I IFNs induce differentiation of dendritic cells (DCs) with potent Ag-presenting capacity, termed IFN-alpha DCs, that have been implicated in the pathogenesis of systemic lupus erythematosus. In this study, we found that IFN-alpha DCs exhibit enhanced migration across the extracellular matrix (ECM) in response to chemokines CCL3 and CCL5 that recruit DCs to inflammatory sites, but not the lymphoid-homing chemokine CCL21. IFN-alpha DCs expressed elevated matrix metalloproteinase-9 (MMP-9), which mediated increased migration across ECM. Unexpectedly, MMP-9 and its cell surface receptors CD11b and CD44 were required for enhanced CCL5-induced chemotaxis even in the absence of a matrix barrier. MMP-9, CD11b, and CD44 selectively modulated CCL5-dependent activation of JNK that was required for enhanced chemotactic responses. These results establish the migratory phenotype of IFN-alpha DCs and identify an important role for costimulation of chemotactic responses by synergistic activation of JNK. Thus, cell motility is regulated by integrating signaling inputs from chemokine receptors and molecules such as MMP-9, CD11b, and CD44 that also mediate cell interactions with inflammatory factors and ECM.
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PMID:Costimulation of chemokine receptor signaling by matrix metalloproteinase-9 mediates enhanced migration of IFN-alpha dendritic cells. 1667 Mar 11


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