cathepsin-g and Lupus-Erythematosus--Systemic

Neutrophil extracellular traps (NETs) are networks of decondensed chromatin loaded with antimicrobial peptides and enzymes produced against microorganisms or biochemical stimuli. Since their discovery, numerous studies made separately have revealed multiple triggers that induce similar NET morphologies allowing to classify them as lytic or non-lytic. However, the variability in NET composition depending on the inducer agent and the local milieu under similar conditions has been scarcely studied. In this work, a comparative study was conducted to evaluate structural and enzymatic divergences in NET composition induced by biochemical (phorbol myristate acetate [PMA] and hypochlorous acid [HOCl]) and microbiologic (Candida albicans, Staphylococcus aureus, and Pseudomonas aeruginosa) stimuli, along with the presence of plasma from healthy donors or patients with systemic lupus erythematosus (SLE). The results showed a differential composition of DNA and the antimicrobial peptide cathelicidin (LL37) and a variable enzymatic activity (neutrophil elastase, cathepsin G, myeloperoxidase) induced by the different stimuli despite showing morphologically similar NETs. Additionally, SLE plasma´s presence increased DNA and LL37 release during NET induction independently of the trigger stimulus but with no enzymatic activity differences. This work provides new evidence about NET composition variability depending on the inducer stimulus and the local milieu.

Topics: Biomarkers; Candida albicans; Case-Control Studies; Cathelicidins; Cathepsin G; Cells, Cultured; Extracellular Traps; Healthy Volunteers; Humans; Hypochlorous Acid; Leukocyte Elastase; Lupus Erythematosus, Systemic; Neutrophils; Peroxidase; Primary Cell Culture; Pseudomonas aeruginosa; Staphylococcus aureus; Tetradecanoylphorbol Acetate

In this study, we examined the content of antineutrophil cytoplasmic antibodies (ANCA) against defensins and cathepsin G in sera from systemic lupus erythematosus (SLE) patients and their significance in estimating the activity of SLE. Defensins- and cathepsin G-ANCA in sera from 28 patients with SLE, eight patients with rheumatoid arthritis (RA) and eight patients with microscopic polyangitis (mPA) were measured by ELISA. Significantly increased defensins- and cathepsin G-ANCA were found in sera of patients with SLE and mPA when compared with the value of normal controls. Though significantly higher defensins- and cathepsin G-ANCA were detected in both active and inactive SLE patients, the value in active SLE patients was significantly higher than inactive SLE patients. After the therapy with high dose of prednisolone, the serum level of defensins- and cathepsin G-ANCA was decreased, and this decrease was sustained for at least 16 weeks. This study suggests that defensins- and cathepsin G-ANCA may serve as useful markers of the disease activity of SLE.

Topics: Adult; Aged; Antibodies, Antineutrophil Cytoplasmic; Arthritis, Rheumatoid; Biomarkers; Case-Control Studies; Cathepsin G; Cathepsins; Defensins; Female; Humans; Lupus Erythematosus, Systemic; Male; Middle Aged; Serine Endopeptidases

Antibodies to human myeloperoxidase and cathepsin G have been detected in the serum of some patients with systemic lupus erythematosus. Therefore, the presence of antibodies to human myeloperoxidase and cathepsin G was examined in glomerular immune deposits. Glomerular basement membrane fragments were prepared from renal tissues obtained at autopsy from 19 patients with systemic lupus erythematosus. IgG was extracted from the glomerular basement membrane fragments and tested with sensitive immunoassays for antibodies to myeloperoxidase and cathepsin G. Antibodies to cathepsin G were not detected in the extracts but antibodies to human myeloperoxidase were found in extracts of one specimen. In the extract with 6M guanidine hydrochloride these antibodies were enriched 103-fold, compared to the initial supernatant of glomeruli, which served as a serum surrogate. The recovered antibodies to myeloperoxidase accounted for 12% of the recovered IgG. These findings add autoantibodies to human myeloperoxidase to the list of antibodies that have been shown to be present in glomerular immune deposits of patients with lupus glomerulonephritis.

Topics: Autoantibodies; Autopsy; Basement Membrane; Cathepsin G; Cathepsins; Humans; Immunoglobulin G; Kidney; Kidney Glomerulus; Lupus Erythematosus, Systemic; Peroxidase; Serine Endopeptidases

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 prevalence and antigen specificity of anti-neutrophil cytoplasmic antibodies (ANCA) in sera from 23 children with active systemic lupus erythematosus (SLE) were studied utilizing indirect immunofluorescence and IgG and IgM ELISA using crude neutrophil extract and purified proteinase 3, myeloperoxidase, lactoferrin, cathepsin G and elastase. ANCA were present in 69% of SLE children and consisted of IgM and IgG antibodies of variable specificities, but did not correlate with organ involvement or disease activity. It remains unclear whether they have pathogenic significance or are epiphenomena in the category of polyclonal B-cell activation. However, their presence is entirely compatible with SLE even though they have hitherto been commonly associated with other systemic vasculitides.

Topics: Antibodies, Antineutrophil Cytoplasmic; Autoantibodies; Case-Control Studies; Cathepsin G; Cathepsins; Child; Epitopes; Female; Humans; Immunoglobulin G; Immunoglobulin M; Lupus Erythematosus, Systemic; Male; Pancreatic Elastase; Serine Endopeptidases