ABSTRACT
A quantitative immunoassay using a highly purified antigen from HeLa cells has allowed us to detect antibodies to SSB/La in 11/20 patients with primary Sjögren's syndrome (SS), 15/33 with SLE, and 11/35 with progressive systemic sclerosis (PSS). However, positive results were found in only 2/12 patients with idiopathic Raynaud's disease and 2/20 with rheumatoid arthritis, including 4 with secondary SS. Anti-SSB/La were associated with extraglandular manifestations in primary SS, and with a diffuse sclerodermic pattern in PSS. In SS, SLE and PSS, a positive anti-SSB/La test was strongly associated with nodal or spleen enlargement and with an increased level of gamma-globulins. A direct association was also found with positive tests for rheumatoid factors, anti-SSA/Ro and anti-Scl 70. An inverse relationship was however found with anti-nRNP +/- Sm and anticentromere antibodies. Our data suggest that anti-SSB/La antibodies can be regarded as a marker of B-lymphocyte activation in patients with either primary SS, SLE or PSS.
Subject(s)
Antibodies, Antinuclear/analysis , Autoimmune Diseases/immunology , Sjogren's Syndrome/immunology , Antibodies, Antinuclear/immunology , Blotting, Western , Connective Tissue Diseases/immunology , Electrophoresis, Polyacrylamide Gel , Enzyme-Linked Immunosorbent Assay , HeLa Cells , Humans , Immunodiffusion , Lupus Erythematosus, Systemic/immunology , Scleroderma, Systemic/immunologyABSTRACT
In this study the specificity of circulating autoantibodies in ANA+ aged donors, ANA- donors and SLE patients was investigated by immunoblotting on total nuclear proteins and by ELISA on purified nuclear proteins, possibly related to DNA metabolism, such as DNA polymerase alpha, DNA-dependent ATPase, DNA Topoisomerase I, ssDBP, hnRNP, HMG and histones. Immunoblotting showed that sera from ANA+ aged donors present fewer antibodies to nuclear proteins, especially to those between 21,000 and 45,000, molecular weight (MW), than sera from SLE patients. When the specificity of antisera was further studied on purified nuclear proteins, it was found that the majority of sera from SLE patients react with most of the proteins tested, whereas sera from ANA+ aged donors mainly react with DNA polymerase alpha, DNA-dependent ATPase, DNA Topoisomerase I and histones. In addition, sera from a few ANA- donors also reacted with certain purified nuclear proteins in a statistically significant age-related manner.
Subject(s)
Aging/immunology , Antibodies, Antinuclear/immunology , DNA/metabolism , Lupus Erythematosus, Systemic/immunology , Adolescent , Adult , Aged , Aged, 80 and over , Antibodies, Antinuclear/analysis , Antibody Specificity , Autoantigens/immunology , Child , Child, Preschool , Electrophoresis, Polyacrylamide Gel , Humans , Infant , Infant, Newborn , Middle AgedABSTRACT
The cytotoxicity of hydrogen peroxide in Escherichia coli was investigated after various conditions of drug exposure. Two modes of killing were detected following a 15-min challenge with H2O2 under either aerated or anoxic conditions. Mode one killing occurred at levels below 2.5 mM and mode two killing at concentrations higher than 10 mM. Whereas mode one killing was similar at the two conditions of drug exposure, mode two lethality differed in that aerated cells were more sensitive than anoxic cells. Independently of O2 tension the hydroxyl radical scavenger, thiourea, prevented mode two but not mode one killing by H2O2. Cells treated with the drug at ice temperature did not display mode one killing and mode two lethality occurred only at very high concentrations. We suggest that hydroxyl radicals mediate mode two but not mode one killing by H2O2.
Subject(s)
Escherichia coli/drug effects , Hydrogen Peroxide/pharmacology , Oxygen/pharmacology , Temperature , Free Radicals , Oxidation-ReductionABSTRACT
1. We have studied the pleiotropic effect of a single-gene mutation of the pts mutant strain 1511 grown at 23 degrees C and 36 degrees C. 2. Growth of the mutant at the non-permissive temperature results in a decrease of respiration rate to about 50% after one generation and to less than 5% after five generations. The cytochrome spectra analysis revealed that only cytochrome c was present after growth at 36 degrees C. 3. Mitochondrial protein synthesis experiments in vivo demonstrated that the protein synthesizing system was not as rapidly inactivated by high temperature as the respiratory system. 4. The recovery of the respiratory capacity of the cells at 23 degrees C is complete but dependent on the de novo synthesis of a temperature sensitive protein.
