alpha-chymotrypsin and Lupus-Erythematosus--Systemic

Of all anti-dsDNA antibody detection methods, the Crithidia luciliae immunofluorescence test (CLIF) is considered to have the highest specificity for systemic lupus erythematosus (SLE).. The objective of this report is to evaluate whether the presence of anti-dsDNA antibodies detected by the CLIF method is associated with a specific clinical phenotype in recently diagnosed SLE.. This retrospective cross-sectional study included all patients with newly diagnosed SLE between 1990 and 2011 and followed up in our institution. Demographic, clinical and laboratory findings were assessed. Correlations between positivity of anti-dsDNA by the CLIF method, clinical and laboratory data were analyzed.. A total of 104 patients were included in the analysis. Patients who were positive for anti-dsDNA by the CLIF method at the time of diagnosis had (statistically) significantly higher titers of anti-dsDNA by the ELISA method, antinuclear (ANA) and anticardiolipin antibodies, lymphopenia and complement consumption compared with the other two groups. Also they presented significantly more musculoskeletal symptoms at baseline.. The presence of anti-dsDNA by the CLIF method in newly diagnosed SLE was associated with certain markers of increased disease activity. Its use could be a useful biomarker for a specific clinical phenotype suggestive of a more severe involvement at the time of the diagnosis.

Topics: Adult; Antibodies, Anticardiolipin; Antibodies, Antinuclear; Chymotrypsin; Complement System Proteins; Crithidia; Cross-Sectional Studies; Female; Fluorescent Antibody Technique; Fluorescent Antibody Technique, Indirect; Humans; Insect Proteins; Lupus Erythematosus, Systemic; Lymphopenia; Male; Middle Aged; Phenotype; Retrospective Studies

Calf thymus histone 1 (H1) was cleaved by chemical and enzymatic methods and the resulting polypeptides were fractionated by high-performance cation-exchange. Up to 1 mg of H1 polypeptides were loaded onto a 50 x 5 mm I.D. cation-exchange column and fractionated to greater than 95% purity in less than 30 min. This is the first report on the separation of H1 polypeptides by a strong cation-exchange matrix. In addition, the high-performance cation-exchange chromatography protocol represents a significant decrease in fractionation time when compared to conventional ion-exchange and gel filtration chromatography. The utility of this procedure is shown when the H1 peptides purified by the protocol were used to define antigenic domains of H1 band by procainamide-induced lupus and idiopathic systemic lupus erythematosus. The majority of the sera tested by enzyme-linked immunoassay (ELISA) reacted to the C-terminal peptides of H1 indicating this to be the major antigenic domain of H1.

Topics: Animals; Bromosuccinimide; Cattle; Chromatography, Liquid; Chymotrypsin; Enzyme-Linked Immunosorbent Assay; Histones; Lupus Erythematosus, Systemic; Procainamide; Sodium Chloride; Thrombin; Thymus Gland

The platelet binding properties of human monoclonal lupus autoantibodies have been studied. These IgM autoantibodies, produced by human X human hybridomas derived from lymphocytes of patients with systemic lupus erythematosus, are known to bind to single-stranded DNA. Four anti-DNA antibodies that express the dominant 16/6 idiotype--HF2-1/17, HF2-18/2, HF2-1/13b, and HF3-16/6--bound to glutaraldehyde-fixed platelets. In contrast, HF6-21/28, HF9-11/3, and polyclonal IgM bound poorly to platelets. [35S]Methionine was incorporated into HF2-1/17, and the interaction of the intrinsically radiolabeled HF2-1/17 with fixed platelets was evaluated in a solution phase radioimmunoassay. [35S]Methionine HF2-1/17 bound to fixed platelets and could be displaced by equivalent amounts of HF2-1/17, HF2-18/2, HF2-1/13b, and HF3-16/6. HF2-1/17 bound with greater affinity to fresh platelets and to thrombin-activated platelets than to glutaraldehyde-fixed platelets. Single-stranded DNA competed with platelets for the HF2-1/17 combining site. Treatment of fresh platelets with nuclease I, trypsin, chymotrypsin, and neuraminidase did not alter the binding of antibody to the platelet surface. No binding of antibody to phospholipid micelles was observed. Purified IgM autoantibodies did not inhibit platelet aggregation induced with ADP, thrombin, or ristocetin in platelet-rich plasma. These results indicate that the human IgM monoclonal anti-DNA autoantibodies that express the dominant 16/6 idiotype are polyspecific, bind to platelets, and interact with a platelet epitope that does not appear to involve DNA, protein, or sialic acid. These antibodies interact with platelets through the same sites responsible for antibody-DNA binding.

Topics: Antibodies, Monoclonal; Antibody Formation; Antigen-Antibody Reactions; Autoantibodies; Binding Sites, Antibody; Blood Platelets; Chymotrypsin; Humans; Hybridomas; Lupus Erythematosus, Systemic; Neuraminidase; Phospholipids; Radioimmunoassay; Trypsin

The investigation concerned 33 systemic lupus erythematosus (SLE) patients assigned to three groups representing mild SLE, more severe extra renal SLE, and SLE with significant renal involvement. In patients with extrarenal disease, the inflammatory plasma protein response was often pronounced during exacerbation, as evidenced by markedly increased concentrations of C-reactive protein (CRP), alpha 1-antichymotrypsin, alpha 1-antitrypsin, and orosomucoid. CRP responses were rare in patients with renal involvement, despite the increased concentrations of other acute-phase reactants in some of these patients. Superimposed bacterial infections were not clearly distinguished by raised CRP concentrations. The classical pathway of complement was activated in all patients during exacerbation, as indicated by increased concentrations of C1r-C1s-C1 inactivator complexes and C2a fragments. C1, C2, and probably also C3 activation varied according to the amounts of circulating C1q-binding immune complexes, as measured by solid-phase assay. Manifest hypocomplementemia was usually associated with glomerulonephritis. Participation of complement components in the inflammatory plasma protein response apparently counteracted the development of hypocomplementemia in many patients with extrarenal SLE. Circulating C3d was detected in all patients during exacerbation of renal disease and in most patients with severe extrarenal manifestations. Inverse relationships were found between immunochemical C2 concentrations and the percentage of cleaved C2 and between C3 and C3d. There was no appreciable consumption of factors B and D and properdin of the alternative pathway in the patients. High concentrations of factor D, a low molecular weight protein, were exclusively found in patients with renal involvement and could be ascribed to retention due to reduced glomerular filtration.

Topics: alpha 1-Antichymotrypsin; alpha 1-Antitrypsin; Antigen-Antibody Complex; Bacterial Infections; C-Reactive Protein; Chymotrypsin; Complement Activating Enzymes; Complement Activation; Complement C1; Complement C1q; Complement C1r; Complement C3; Complement C4; Complement System Proteins; Humans; Lupus Erythematosus, Systemic; Orosomucoid

Topics: Adult; Amyloidosis; Antimetabolites; Chymotrypsin; Female; Glomerulonephritis; Humans; Kidney Diseases; Lupus Erythematosus, Systemic; Male; Middle Aged; Nephrotic Syndrome; Prednisolone; Pyelonephritis; Trypsin; Trypsin Inhibitors

Topics: Alpha-Globulins; Antigens; Benzoates; Chymotrypsin; Complement Fixation Tests; Cytoplasm; Hydrogen-Ion Concentration; Immunodiffusion; Immunoelectrophoresis; Lupus Erythematosus, Systemic; Mercury; Pepsin A; Periodic Acid; Solubility; Spleen; Tissue Extracts; Trypsin

Topics: Arthritis; Arthritis, Rheumatoid; Chymotrypsin; Cyclophosphamide; Femoral Artery; Heparin; Humans; Injections, Intra-Articular; Lupus Erythematosus, Systemic; Scleroderma, Systemic; Spondylitis, Ankylosing