lactoferrin and Lupus-Erythematosus--Systemic

To evaluate specificity, level, and avidity of antineutrophil cytoplasmic antibodies (ANCA) in systemic lupus erythematosus (SLE). There are no studies of ANCA avidity in SLE.. Level (ELISA) and avidity (ELISA) of myeloperoxidase (MPO-), proteinase 3 (PR3-), lactoferrin (LF-), cathepsin G, elastase (EL-), and bactericidal/permeability increasing protein (BPI)-ANCA in 142 SLE patients were studied. SLE activity was measured by SLEDAI-2 K. 25/40 ANCA-positive patients were immunoserologically followed (12 ± 2 months).. 40/142 (28.2%) SLE patients were ANCA-positive: LF- (21/40), MPO- (19/40), EL- (6/40), PR3- (3/40), and BPI-ANCA (1/40). Only LF-ANCA were associated with renal manifestations (p < 0.05), and positive predictive value for renal involvement in ANCA-positive SLE was 76.2%. LF-ANCA-positive patients had higher SLEDAI-2 K (p < 0.05) and more frequently had anti-dsDNA (p < 0.05), low C3 (p < 0.001), and low C4 (p < 0.05) than LF-ANCA-negative patients. LF-ANCA level was in a positive correlation with SLEDAI-2 K, anti-dsDNA, and anti-C1q (p < 0.01) and in a negative correlation with C3 and C4 (p < 0.05). LF-ANCA avidity was higher than MPO-, EL-, PR3-, and BPI-ANCA avidity (p < 0.01). In LF-ANCA-positive patients, renal manifestations were associated with higher LF-ANCA level (p < 0.01) and avidity (p < 0.05). Based on LF-ANCA level and avidity, the receiver operating characteristic curves for discriminating patients with and without renal involvement had areas under the curves of 0.988 (95% CI: 0.949-1.00) and 0.813 (95% CI: 0.607-1.00), respectively. After the follow-up period, number of LF-ANCA-positive patients decreased (p < 0.01).. In contrast to other ANCAs, only LF-ANCA level correlated with activity and standard serological SLE markers. LF-ANCA level and avidity might be biomarkers of renal involvement in SLE. LF-ANCA are promising serological marker in SLE. Key Points • LF- and MPO-ANCA were most frequently found, while EL-, PR3-, and BPI-ANCA were rarely detected in SLE. • In contrast to other ANCAs, only LF-ANCA were associated with renal involvement, and their level correlated with the activity and standard serological markers of SLE. • LF-ANCA avidity was higher than other ANCAs' avidity; LF-ANCA level and avidity might be useful biomarkers of renal manifestations in SLE. • Detection of ANCA specificity, level, and avidity may help in the diagnosis of particular clinical SLE phenotypes.

Topics: Antibodies, Antineutrophil Cytoplasmic; Biomarkers; Enzyme-Linked Immunosorbent Assay; Humans; Lactoferrin; Lupus Erythematosus, Systemic; Myeloblastin; Peroxidase

Lactoferrin (LF) has beneficial effects against various diseases. However, the effects of LF on liver fibrosis in systematic lupus erythematosus (SLE) are unknown. In this study, NZB/W F1 mice were utilized to investigate the effects of LF on SLE. Experiments reveal that LF significantly increases glutathione and 1,1-diphenyl-2-picryl-hydrazyl levels and significantly decreased malondialdehyde levels in both serum and liver in NZB/W F1 mice. LF also lowered matrix metalloproteinase-9 activity and liver inflammatory indices, such as aminotransferase and alanine aminotransferase. Notably, significantly decreased expression of fibrotic related molecules, including transforming growth factor (TGF)-β1, tumor necrosis factor-α, interleukin-1β, and TGF-β1 receptor, were observed in the livers of NZB/W F1 mice that had been treated with LF. Significantly, suppressed Smad2/3 signaling, α-smooth muscle actin, and collagen deposition were also detected. These findings reveal that LF has beneficial effects on SLE by increasing antioxidant activities and ameliorating liver inflammation and fibrosis, suggesting the therapeutic effectiveness of LF against SLE.

Topics: Alanine Transaminase; Animals; Antioxidants; Aspartate Aminotransferases; Cholesterol, Dietary; Cytokines; Glutathione; Lactoferrin; Liver; Liver Cirrhosis; Lupus Erythematosus, Systemic; Matrix Metalloproteinase 9; Mice; Mice, Inbred NZB; Signal Transduction; Smad2 Protein; Smad3 Protein

The aim of the present study was to investigate mechanism of the gender differences of B cells. The results showed that 358 differential gene expressions (DEGs) were displayed between healthy females and males. Compared with male, 226 and 132 genes were found to be up- and downregulated in the female. 116 genes displayed possible correlation with estrogen. Moreover, the upregulated DEGs (Cav1, CD200R1, TNFRSF17, and CXCR3) and downregulated DEGs (EIF1AY and DDX3Y) in healthy female may be involved in gender predominance of some immune diseases. Furthermore, signaling pathway analysis for estrogen-relevant DEGs showed that only 26 genes were downregulated in SLE female versus SLE male, of which expressions of 8 genes had significant difference between SLE females and SLE males but are having nonsignificant difference between healthy females and healthy males. Except for the 5 Y-chromosome-related genes or varients, only 3 DEGs (LTF, CAMP, and DEFA4) were selected and qRT-PCR confirmed that the expressions of LTF and CAMP decreased significantly in B cells from female SLE patients. These data indicated that the gender differences were existent in global gene expression of B cells and the difference may be related to estrogen.

Topics: Adult; Animals; Antimicrobial Cationic Peptides; B-Lymphocytes; Cathelicidins; Estrogens; Female; Gene Expression Profiling; Gene Expression Regulation; Humans; Lactoferrin; Lupus Erythematosus, Systemic; Male; Mice; Sex Characteristics; Sex Factors; Signal Transduction

It is conceivable that a membrane component(s) is transferred from antigen-presenting cells to T cells after antigenic stimulation. However, it is not clear whether a certain membrane component(s) is transferred from polymorphonuclear neturophils (PMN) to T cells for immunomodulation. In the presence study, we cocultured two of the three autologous cells-PMN, CD4+ T, and red blood cells (RBC)-homotypically or heterotypically for 1 h. Spontaneous membrane exchange between autologous PMN-PMN and PMN-CD4+ T but not between CD4+ T-CD4+ T or RBC-CD4+ T was observed with a confocal microscope. Loss of membrane exchange between two paraformaldehyde-fixed cells suggests that mutual membrane exchange is via cell-cell contact. Different combinations of cellular enzyme-linked immunosorbent assay for measuring the binding between fixed cells and biotinylated cell lysates showed the same tendency. To identify the molecule(s) mediating PMN-CD4+ T binding, we compared the banding of biotinylated PMN lysates and the banding of plain PMN lysate probed by biotinylated CD4+ T lysate in 10% sodium dodecyl sulfate-polyacrylamide gel electrophoresis. We found that a 75- to 80-kDa surface-expressed molecule on PMN exists constantly to mediate PMN-CD4+ T binding. Peptide analysis disclosed that the molecule had 99.8% identity with lactoferrin (LF). The expression of LF on system lupus erythematosis (SLE)-PMN is less than normal PMN. PMN-CD4+ T coculture increased LF expression on CD4+ T. Normal PMN and human milk-derived LF suppressed interferon-gamma (IFN-gamma) but enhanced interleukin (IL)-10 production of anti-CD3+anti-CD28-activated, normal CD4+ T. In contrast, coculture of SLE-PMN and autologous CD4+ T suppressed IFN-gamma and IL-10 production. These results suggest that the surface-expressed LF released from PMN after contact with autologous CD4+ T modulated its T helper cell type 1 (Th1)/Th2 cytokine production. Decreased LF expression on SLE-PMN abnormally modulates Th1/Th2 production by CD4+ T cells.

Topics: Antigens, Surface; Blotting, Western; Case-Control Studies; CD4-Positive T-Lymphocytes; Cell Membrane; Enzyme-Linked Immunosorbent Assay; Erythrocytes; Humans; Lactoferrin; Lupus Erythematosus, Systemic; Neutrophils; Paracrine Communication; Th1 Cells; Th2 Cells

Lactoferrin (LF) is a multifunctional iron-binding protein present in several mucosal secretions as well as in secondary granules of polymorphonuclear leukocytes (PMN). Anti-LF antibodies, which belong to antineutrophil cytoplasmic antibodies (ANCA), have been described in several immunomediated diseases, including systemic lupus erythematosus (SLE), with conflicting results regarding either their prevalence or clinical associations. We studied the prevalence and isotype distribution of anti-LF and their association with clinical manifestations, disease activity, and other autoantibodies in 97 patients (83 women) affected by SLE. Anti-LF were detected by enzyme-linked immunosorbent assay. Disease activity was assessed using the Systemic Lupus Activity Measure (SLAM). Cutoff for antibody positivity was set at three standard deviations (SD) above the mean optical density obtained in sera from 34 healthy subjects. Positive sera were arbitrarily subdivided into low (from >3 to 5 SD), medium (from >5 to 10 SD), and high (>10 SD) positive. IgG, IgM, and IgA anti-LF were detected in 53, 18, and 14 patients, respectively. IgG1, IgG2, IgG3, and IgG4 anti-LF were demonstrated in 34, 10, 31, and 35 patients, respectively. IgG anti-LF at the medium/high level were found in 33 patients, correlated with disease activity (p = 0.017), anti-dsDNA (0.04), and anticardiolipin antibodies (p = 0.02) and were associated with Raynaud's phenomenon (p = 0.028), renal involvement (p = 0.007), serositis (p = 0.026), and history of thrombosis (p = 0.006). Anti-LF of IgM, IgA, or IgG subclass isotypes showed no correlation with clinical and serological findings. Our results demonstrate that anti-LF are frequently present in patients affected by SLE. IgG anti-LF at the medium/high level are associated with some clinical manifestations and other autoantibodies. However, it remains to be established whether anti-LF play a specific pathogenic role.

Topics: Adolescent; Adult; Antibodies, Antineutrophil Cytoplasmic; Biomarkers; Cohort Studies; Disease Progression; Enzyme-Linked Immunosorbent Assay; Female; Humans; Immunoglobulin Isotypes; Lactoferrin; Lupus Erythematosus, Systemic; Male; Middle Aged; Prevalence; Probability; Prognosis; Risk Assessment; Sensitivity and Specificity; Severity of Illness Index; Statistics, Nonparametric

The IgG subclasses displayed by antibodies to four neutrophil cytoplasmic antigens were studied in 20 patients with systemic lupus erythematosus (SLE) by solid-phase enzyme immunoassays and monoclonal antibodies to human IgG subclasses. The IgG subclass reactivity of antineutrophil cytoplasmic antibodies (ANCA) was measured in six sera containing antiproteinase3 (PR3) antibodies, in five sera containing antimyeloperoxidase (MPO) antibodies, in sera containing antibactericidal/permeability-increasing protein (BPI) antibodies, and in ten sera containing antilactoferrin (LF) antibodies. The IgG subclass distribution of anti-dsDNA antibodies in eight sera was examined as well. IgGI was the predominant subclass for MPO-ANCA and LF-ANCA, whereas IgG1/IgG3 contributed mainly to anti-PR3, anti-BPI antibodies, and anti-dsDNA antibodies. In addition, we found elevated levels of the total IgG1 and IgG3 isotypes in the sera of our patients. Our results demonstrated a predominance of IgG1/IgG3 ANCA in SLE, suggesting that the isotype distribution of ANCA is a feature of antibody production in this disease.

Topics: Adolescent; Adult; Aged; Anti-Infective Agents; Antibodies, Antineutrophil Cytoplasmic; Antibodies, Monoclonal; Antimicrobial Cationic Peptides; Blood Proteins; Cohort Studies; Enzyme-Linked Immunosorbent Assay; Female; Humans; Immunoglobulin G; Lactoferrin; Lupus Erythematosus, Systemic; Membrane Proteins; Middle Aged; Myeloblastin; Peroxidase; Serine Endopeptidases

Fifty-five patients with systemic lupus erythematosus (SLE) were examined for antineutrophil cytoplasmic antibodies (ANCA) by indirect immunofluorescence (IIF). Enzyme-linked immunosorbent assay (ELISA) for ANCA against myeloperoxidase (MPO), lactoferrin (LF), proteinase 3 (PR3), elastase (HLE), and bactericidal/permeability-increasing protein (BPI) was performed. The prevalence of ANCA by IIF was 29.1% (16/55 patients). MPO-ANCA were found in 10.9% (6/55), LF-ANCA in 18.2% (10/55), PR3-ANCA in 12.7% (7/55), BPI-ANCA in 23.6% (13/55), and HLE-ANCA in 1.8% (1/55). The levels of BPI-, LF-, and PR3-ANCA correlated with disease activity. A significant association between serositis and the presence of BPI-, LF-, and PR3-ANCA was observed, and PR3-ANCA were found to be associated with arthritis as well. Our results demonstrate that ANCA of various specificities occur in SLE, and BPI appears to be an important target antigen.

Topics: Adolescent; Adult; Aged; Antibodies, Antineutrophil Cytoplasmic; Antimicrobial Cationic Peptides; Blood Proteins; Bulgaria; Child; Enzyme-Linked Immunosorbent Assay; Female; Fluorescent Antibody Technique, Indirect; Humans; Lactoferrin; Lupus Erythematosus, Systemic; Male; Membrane Proteins; Middle Aged; Myeloblastin; Pancreatic Elastase; Peroxidase; Serine Endopeptidases; Severity of Illness Index

To investigate the prevalence and clinical relevance of immunoglobulin (Ig) isotypes of antimyeloperoxidase (MPO) and antilactoferrin (LF) antibodies in collagen diseases, enzyme-linked immunosorbent assay was employed to detect the Ig isotypes of both antibodies. The purified proteins of MPO and LF were used as two major representative antigens for anti-neutrophil cytoplasmic antibodies (ANCA) with a perinuclear staining pattern by an indirect immunofluorescent technique. We examined 131 serum samples from 79 patients with rheumatoid arthritis (RA), 32 with systemic lupus erythematosus (SLE), 14 with progressive systemic sclerosis (PSS), 6 with polymyositis/dermatomyositis (PM/DM), and 5 with idiopathic crescentic glomerulonephritis who served as positive controls and 36 healthy subjects who served as controls. A limited number of patients with RA (4-10%), SLE (6-9%), and PSS (7-14%) but not PM/DM showed positive IgG or IgA anti-MPO antibody (MPO-ANCA) but not IgM MPO-ANCA. However, 10-20% of RA, 40-60% of SLE, 20-36% of PSS but none of the PM/DM patients showed positive IgG, IgA, or IgM anti-LF antibody (LF-ANCA). MPO- and LF-ANCA positivity in RA patients was correlated with markers of disease activity such as the erythrocyte sedimentation rate, C-reactive protein, and serum Ig levels. IgG LF-ANCA but not MPO-ANCA positivity in SLE patients also was correlated with the disease activity index but not with clinical features. Neither MPO- nor LF-ANCA positivity in PSS patients was correlated with any clinical features. Overall, both MPO- and LF-ANCA were found mainly in RA, SLE, and PSS patients but not in PM/DM patients. The Ig isotypes of MPO- and LF-ANCA frequently belonged to both IgG and IgA and rarely to the IgM class. Both MPO- and LF-ANCA positivity reflected disease activity in RA and SLE rather than specific organ involvement.

Topics: Adult; Aged; Aged, 80 and over; Antibodies, Antineutrophil Cytoplasmic; Antibody Specificity; Arthritis, Rheumatoid; Autoantigens; Autoimmune Diseases; Collagen Diseases; Dermatomyositis; Enzyme-Linked Immunosorbent Assay; Female; Glomerulonephritis; Humans; Immunoglobulin A; Immunoglobulin G; Immunoglobulin Isotypes; Immunoglobulin M; Lactoferrin; Lupus Erythematosus, Systemic; Male; Middle Aged; Organ Specificity; Peroxidase; Polymyositis; Scleroderma, Systemic

This investigation was designed to determine and compare the distribution pattern of anti-neutrophil cytoplasmic antibodies (ANCA) in patients with systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) in the presence or absence of periodontal disease.. Sera of 30 patients with SLE and 30 with RA were tested for ANCA utilizing an indirect enzyme immunosorbent assay (ELISA) directed to a neutrophil granular extract and 6 neutrophil granule proteins. A control group of 20 healthy individuals showing neither evidence of periodontal disease nor systemic compromise was also included in this study.. For RA, the number of ANCA-positive sera was very low but was evenly distributed among patients with and without periodontitis. Conversely, a high number of ANCA-positive sera in SLE was found mostly in individuals presenting periodontal compromise. A statistically significant association between ANCA and periodontitis in SLE patients was found (P <0.005, chi square test).. A marked difference in the number and distribution of ANCA with respect to periodontitis between RA and SLE was found. Hyperresponsiveness of B cells and polyclonal B activation to periodontopathic bacteria in SLE might be accountable for the high numbers of ANCA and the close association observed between those autoantibodies and periodontitis in SLE.

Topics: Adult; Antibodies, Antineutrophil Cytoplasmic; Arthritis, Rheumatoid; Autoantigens; B-Lymphocytes; Bacteria; Cathepsin G; Cathepsins; Chi-Square Distribution; Enzyme-Linked Immunosorbent Assay; Female; Humans; Lactoferrin; Leukocyte Elastase; Lupus Erythematosus, Systemic; Lymphocyte Activation; Male; Middle Aged; Muramidase; Myeloblastin; Neutrophils; Periodontitis; Peroxidase; Serine Endopeptidases

The objectives of this study is to determine if periodontitis-related ANCA hinder the accurate estimation of this kind of autoantibodies in systemic lupus erythematosus (SLE), due to the frequent coexistence of SLE and periodontitis, and the high incidence of antineutrophil cytoplasmic antibodies (ANCA) in this periodontal condition. Thirty SLE, thirty periodontitis lacking systemic involvement patients, and twenty healthy controls were utilized in this study. The periodontal condition and the presence of ANCA in sera of all individuals was carefully evaluated. For ANCA determination an EIA assay was utilized, directed to a neutrophil granular extract and six neutrophil granule proteins. Sixty percent of SLE patients had periodontitis, and sixty-five percent were ANCA positive. Eighty three percent of all ANCA cases were coexisting with periodontitis. A significant association (p > 0.005) between periodontitis and ANCA was found (Chi Square Test). Fifty percent of the patients with periodontitis lacking systemic involvement were ANCA positive. The results obtained in this study suggest that the figures of ANCA previously reported for SLE, might be overestimated due to the inadvertent presence of periodontitis.

Topics: Adolescent; Adult; Antibodies, Antineutrophil Cytoplasmic; Autoantigens; Chi-Square Distribution; Female; Humans; Immunoenzyme Techniques; Lactoferrin; Lupus Erythematosus, Systemic; Male; Middle Aged; Myeloblastin; Periodontitis; Pilot Projects; Serine Endopeptidases

We determined the occurrence of antineutrophil cytoplasmic antibodies (ANCAs) and their specificities in 77 rheumatoid arthritis (RA) patients and compared them with 25 patients with psoriatic arthritis (Pso), 19 with drug-induced lupus erythematosus (DI-LE) and 11 with systemic lupus erythematosus (SLE). Thirty-two percent of RA patients had positive indirect immunofluorescence (IIF) stains (P or atypical ANCA). Twenty-nine per cent of patients with rheumatoid vasculitis (RAV), 48% with long-standing RA (LSRA) and 20% with early RA (Ely RA) had positive ANCAs compared with 4% of Pso patients, 47% of DI-LE patients and 45% of SLE patients. Western blotting (with polymorphonuclear cell extracts or alpha-granules) and alpha-granule enzyme-linked immunosorbent assay (ELISA) yielded variable results and proved unhelpful for characterizing the specificities of ANCAs. ELISAs based on commercial purified lactoferrin (LF), myeloperoxidase (MPO), human elastase (HLE) and cathepsin G (CG) showed that anti-HLE antibody was the most prevalent (14%) antibody in RA, followed by anti-MPO antibody and anti-LF antibody (10% each). Statistical analysis of antibody prevalence by clinical presentation showed that LSRA patients were more likely to have anti-HLE antibody and that DI-LE patients were more likely to have anti-CG antibody compared with the other patient groups. In lupus patients serial ELISA titration of ANCAs (LF and MPO) was found to be reliable for predicting the outcome. The overall incidence of ANCAs in RA patients was 33% by IIF.

Topics: Antibodies, Anti-Idiotypic; Antibodies, Antineutrophil Cytoplasmic; Antibody Specificity; Arthritis, Psoriatic; Arthritis, Rheumatoid; Autoantibodies; Biomarkers; Humans; Immunoglobulin G; Lactoferrin; Lupus Erythematosus, Systemic; Pancreatic Elastase; Peroxidase; Time Factors

Antibodies directed against neutrophil granulocyte components have gained an increasing importance in diagnosing systemic vasculitis diseases. The present study was aimed to investigate distribution of anti-lactoferrin antibodies in systemic lupus erythematosus, the hydralazine-induced SLE-like syndrome, and in rheumatoid arthritis compared to RA complicated with vasculitis. Antibodies were detected by ELISA and verified by Western blotting and inhibition assay. Sera positive for IgM were absorbed to remove the rheumatoid factor. IgG and IgM anti-lactoferrin antibodies were found in SLE in 5% and 10% respectively. All patients with hydralazine-induced SLE had antibodies of both isotypes and the antibody level declined rapidly after withdrawal of the drug. In rheumatoid arthritis no IgG anti-lactoferrin antibodies were found, but 20% of the patients with vasculitis had IgM antibodies. Anti-lactoferrin antibodies seem partly to discriminate between genuine and hydralazine-induced SLE, which might indicate a pathogenic relevance in drug-induced autoimmunity. In uncomplicated rheumatoid arthritis it can be concluded that anti-lactoferrin antibodies lack clinical, as well as pathogenic relevance.

Topics: Adult; Aged; Aged, 80 and over; Antibodies, Anti-Idiotypic; Arthritis, Rheumatoid; Female; Humans; Hydralazine; Immunoglobulin G; Immunoglobulin M; Lactoferrin; Lupus Erythematosus, Systemic; Male; Middle Aged; Vasculitis

Thirty-five sera with binding greater than 20% in a myeloperoxidase (MPO, Calbiochem) ELISA were tested in Western blot analyses. 5/35 blotted MPO, but 5/35 blotted lactoferrin (LF) contaminating the commercial MPO preparation. All the anti-LF positive sera, but none of the anti-MPO positive sera, also exhibited anti-nuclear binding on Hep2 cells. Three of the patients with anti-LF antibodies had vasculitis affecting areas additional to the pulmonary-renal involvement which characterised the patients with anti-MPO antibodies.

Topics: Antibodies, Antineutrophil Cytoplasmic; Antibodies, Antinuclear; Antibody Specificity; Autoantibodies; Blotting, Western; Cyanogen Bromide; Enzyme-Linked Immunosorbent Assay; Fluorescent Antibody Technique; Humans; Lactoferrin; Lupus Erythematosus, Systemic; Peroxidase; Sequence Analysis; Sequence Homology; Vasculitis

Antibodies to lactoferrin were detected in about 20% of patients with SLE, irrespective of the presence of renal involvement and in 10% of patients with rheumatoid arthritis and in 19% of patients with scleroderma. We conclude that anti-lactoferrin antibodies may be found in different types of connective tissue disease. Their clinical significance in these diseases however remains to be elucidated.

Topics: Antibodies, Antineutrophil Cytoplasmic; Antibody Specificity; Arthritis, Rheumatoid; Autoantibodies; Autoantigens; Connective Tissue Diseases; Humans; Immunoglobulin G; Lactoferrin; Lupus Erythematosus, Systemic

The prevalence and clinical significance of antineutrophil cytoplasmic antibodies with specificity for lactoferrin was determined in patients with renal diseases. Antilactoferrin antibodies were found in only 12 of 920 patients (1.3%). These patients had either "pauci-immune" necrotizing crescentic glomerulonephritis (three cases) or lupus nephritis (nine cases). To verify whether antilactoferrin antibodies were specific for patients with systemic lupus erythematosus (SLE) and renal involvement, we studied 61 additional lupus patients, 40 with active lupus nephritis and 21 with active SLE and no renal involvement. Antilactoferrin antibodies were found in approximately 15% to 20% of patients with SLE, irrespective of the presence of renal involvement. We conclude that antineutrophil cytoplasmic antibodies with specificity for lactoferrin are only sporadically found in patients with renal diseases; these patients have either necrotizing crescentic glomerulonephritis or lupus nephritis. However, antilactoferrin antibodies are not a marker for renal involvement in SLE.

Topics: Adolescent; Adult; Aged; Antibodies, Antineutrophil Cytoplasmic; Antibody Specificity; Arthritis, Rheumatoid; Autoantibodies; Blotting, Western; Enzyme-Linked Immunosorbent Assay; Female; Fluorescent Antibody Technique; Humans; Lactoferrin; Lupus Erythematosus, Systemic; Lupus Nephritis; Male; Middle Aged; Neutrophils; Scleroderma, Systemic

Lactoferrin is a secondary granule protein of neutrophils. Seventy-nine systemic lupus erythematosus patients who fulfilled the ARA criteria for classification were tested for antibody against human lactoferrin (LF-ab) by ELISA. Thirty-one of these (39.2%) demonstrated elevated levels. There was significant correlation between LF-ab positivity and disease duration. Clinical flare was common with positive LF-ab (P less than 0.05). Disease manifestations were independent of antibody status except for an increased incidence of lymphadenopathy and crescentic gomerulonephritis among those who had LF-ab. No consistent immunofluorescence pattern could be demonstrated on alcohol-fixed neutrophils for the LF-ab positive sera. It is suggested that LF-ab is related to lupus activity, and can be useful as a marker for disease monitoring.

Topics: Adolescent; Adult; Antibodies, Antineutrophil Cytoplasmic; Autoantibodies; Biomarkers; Enzyme-Linked Immunosorbent Assay; Female; Fluorescent Antibody Technique; Humans; Lactoferrin; Lupus Erythematosus, Systemic; Lupus Nephritis; Lymphatic Diseases; Male; Middle Aged

Systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) are prototypes of autoimmune diseases. In order to assess the inflammatory status in these conditions, lactoferrin, stored in specific granules of neutrophils, was measured in serum samples of patients with SLE and RA. In RA, the mean serum lactoferrin level (1221.397 +/- 289.476 ng/ml) was significantly higher than that in normal individuals (753.364 +/- 124.063 ng/ml). Surprisingly, there were no significant differences between active SLE (672.682 +/- 356.154 mg/ml) and inactive SLE (642.267 +/- 270.456 ng/ml). Still, no differences were found between normal volunteers, active SLE and inactive SLE. Serum lactoferrin in SLE correlated significantly with CRP (Rs = 0.4089, p less than 0.01), but not with complement level and ANA titers. Thus in RA serum lactoferrin was highly elevated and this indicated that PMN in systemic circulation was activated. In SLE the correlation of CRP with lactoferrin reflected the role of later protein in inflammation.

Topics: Adolescent; Adult; Arthritis, Rheumatoid; Female; Humans; Lactoferrin; Lupus Erythematosus, Systemic; Male; Neutrophils

In order to assess lactoferrin (LF), stored in specific granules of neutrophils, as a marker of inflammation, LF was measured in plasma and serum samples of patients with active rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). In active RA, the median plasma LF level (800 ng/ml) was significantly higher than in normal individuals (220 ng/ml) (P less than 0.00001) and patients with active SLE (235 ng/ml) (P less than 0.00001). Median plasma elastase-proteinase inhibitor complex (EPIC) and C-reactive protein (CRP) levels were also significantly higher in patients with RA than in normal individuals (P less than 0.00001) and active SLE (P less than 0.00001 for both EPIC and CRP). Elevations of LF, EPIC and CRP in RA were independent of rheumatoid factor titres. Plasma lactoferrin in RA correlated significantly with EPIC (Rs = 0.7, P less than 0.0001), CRP (Rx = 0.72, P less than 0.0001) and absolute neutrophil counts (Rs = 0.483, P less than 0.02), but surprisingly not with the Ritchie index, with which CRP showed a weak but significant correlation (Rs = 0.27, P less than 0.05 greater than 0.025). Thus plasma LF and EPIC are markers of inflammation in RA and their levels may reflect release of mediators of inflammation into the joint space and periarticular tissue.

Topics: Adolescent; Adult; Arthritis, Rheumatoid; Blood Sedimentation; C-Reactive Protein; Female; Humans; Lactoferrin; Lactoglobulins; Leukocyte Count; Lupus Erythematosus, Systemic; Male; Middle Aged; Neutrophils; Pancreatic Elastase

Topics: Antibodies, Monoclonal; Gastric Mucosa; Histocytochemistry; Humans; Immunohistochemistry; Lactoferrin; Leukocytes, Mononuclear; Lichen Planus; Lupus Erythematosus, Systemic; Mouth Diseases; Salivary Glands; Salivary Glands, Minor; Sjogren's Syndrome; T-Lymphocytes

Circulating phagocytes play a major role in the defence of the host against microbial infection. In an attempt to identify the reason for the unusual susceptibility to infection of patients with systemic lupus erythematosus (SLE) various parameters of phagocytic cell function were assessed kinetically in whole blood, and the accumulation of cells in areas of inflammation was studied in vivo with the skin window technique. The effect on these parameters of conventional therapy with glucocorticoids and pulse therapy with large doses of methylprednisolone were examined. Patients on conventional doses of steroids had no abnormality of phagocyte function that might have predisposed to infection, apart from a reduced accumulation of monocytes in areas of inflammation and decreased lactoferrin secretion. Pulse therapy with methylprednisolone considerably delayed the secretion of lactoferrin and the adherence of neutrophils in most of the patients, as well as impairing bacterial killing and digestion.

Topics: Adult; Cell Count; Cell Movement; Female; Humans; Lactoferrin; Lupus Erythematosus, Systemic; Methylprednisolone; Methylprednisolone Hemisuccinate; Middle Aged; Neutrophils; Phagocytes; Phagocytosis; Staphylococcus aureus; Streptococcus pneumoniae; Time Factors

LF was found to bind to deoxyribonucleic acid as assessed by immunofluorescence studies on cell nuclei, affinity chromatography of DNA on immobilized LF, and gel chromatography of an LF-DNA reaction mixture. LF immobilized on Sepharose 4-B was reacted with 125I-labeled DNA in both its double-stranded and single-stranded configurations; dsDNA eluted with a 0.69M NaCl buffer, whereas ssDNA eluted with a 0.25M NaCl buffer. Additional evidence for a preferential reactivity with dsDNA was provided by the enzymatic treatment of preformed dsDNA-LF and ssDNA-LF complexes with S1 endonuclease, and DNAse 1--DNase digestion alone liberated free LF. The interaction of LF with DNA partially inhibited the binding of anti-DNA antibodies from patients with SLE, as assayed in a standard Farr assay. Furthermore, DNA-anti-DNA (labeled with 125I-IgG) complexes could be dispersed in vitro by the addition of LF. It is hypothesized that the release of LF by neutrophils chemotactically attracted to DNA-anti-DNA complexes may act as a feedback loop to modulate the inflammatory response in SLE.

Topics: Antigen-Antibody Complex; Binding Sites; Chromatography, Affinity; Chromatography, Gel; Deoxyribonucleases; DNA; Endonucleases; Fluorescent Antibody Technique; Humans; Immunodiffusion; Immunologic Techniques; Lactoferrin; Lactoglobulins; Lupus Erythematosus, Systemic; Single-Strand Specific DNA and RNA Endonucleases

The synovial lactoferrin (LF) concentrations of 59 patients with active rheumatoid arthritis were determined. The median value of LF was 4.64+/-3.59 mg/100 ml, but in degenerative arthropathy the levels of the metal-protein were much lower and often not titratable. These variations in the LF concentration explain the low blood-iron levels in inflammatory states, even when the concentration of the metal-protein is not statistically correlated in inflammatory tests, IgG, complement fractions (of the normal or alternate pathway), or variations of other protein fractions of leucocyte origin.

Topics: Arthritis, Rheumatoid; Humans; Knee Injuries; Lactoferrin; Lactoglobulins; Lupus Erythematosus, Systemic; Sprains and Strains; Synovial Fluid