Soluble Cytoplasmic Antigen Research Articles

Production of specific brucellin to diagnose Brucellosis

act : A soluble cytoplasmic antigen (Brucellin) was prepared from Brucella melitensis Rev1 and used to diagnose brucellosis in experimentally infected mice with virulent strains of Brucella melitensis and Brucella abortus two weeks after infection. The best result was obtained with the third peak of the four peaks. All four peaks were used as antigen for skin test in a group of mice two weeks after vaccinated with S19 vaccine and the best result was obtained with third peak. All four peaks were also used as antigen for skin test in a group of mice previously vaccinated with Listeria monocytogenes live attenuated vaccine. All four fractions of the extracted brucellin antigens exhibited a negative skin test result in Listeria monocytogenes experimentally vaccinated mice.

Production of specific brucellin to diagnose Brucellosis

act : A soluble cytoplasmic antigen (Brucellin) was prepared from Brucella melitensis Rev1 and used to diagnose brucellosis in experimentally infected mice with virulent strains of Brucella melitensis and Brucella abortus two weeks after infection. The best result was obtained with the third peak of the four peaks. All four peaks were used as antigen for skin test in a group of mice two weeks after vaccinated with S19 vaccine and the best result was obtained with third peak. All four peaks were also used as antigen for skin test in a group of mice previously vaccinated with Listeria monocytogenes live attenuated vaccine. All four fractions of the extracted brucellin antigens exhibited a negative skin test result in Listeria monocytogenes experimentally vaccinated mice.

Role of autoantibodies in the pathogenesis and association of endocrine autoimmune disorders.

This review has focused on the nature and significance of aAB detected in the serum of patients with EAD. Although many antibodies are characteristically detected in the serum of patients with such disorders, only a few are of known pathogenic significance. Antibodies that react with soluble cytoplasmic antigens are not expected to be harmful. On the other hand, membrane or cell surface-directed antibodies are likely to be damaging, either by lysis of the cell membrane, or by reaction with hormone or other surface receptors. Clinically, measurement of aAB has important diagnostic and management value. Moreover, detection of certain antibodies before the onset of disease raises hope that the corresponding disorders may be preventable, e.g. by specific immunosuppression of those subjects, or patients, with positive tests. The possible role of aAB in the association of organ-specific AID by cross-reacting with shared epitopes in various tissues has been highlighted by the recent finding, from the authors' laboratory, of antibodies reactive with a 64-kDa membrane protein found in several tissues, including thyroid, eye muscle, and pancreas, which are frequent sites for autoimmune inflammation. Study of such antibodies and the molecular characterization of the corresponding antigens in the various involved tissues should provide information concerning the role of cross-reactivity in autoimmunity as well as leading to the development of specific immunotherapeutic agents.

Monoclonal antibodies against a soluble cytoplasmic antigen in human prostatic epithelial cells.

Antibodies against a soluble cytoplasmic protein contained in prostate epithelial cells were developed using the hybridoma technique. This was done to provide markers for these cells that can be used to identify acinar cells in culture and to follow their development and/or differentiation over long periods of time. The antibodies do not recognize prostatic acid phosphatase nor the prostate antigen. They do recognize prostate acinar cells in formalin fixed tissue sections. The basal cells underlying the prostate epithelial acinar cells do not appear to contain the antigen. The antigen detected is believed to be a product of differentiated prostatic acinar cells.

Immunochemical characteristics of an IraqiLeishmania donovani

The soluble cytoplasmic antigens of an Iraqi L. donovani stock, characterized by the possession of a unique glucose phosphate isomerase, revealed the presence of over 30 precipitation arcs when diffused against homologus antisera following electrophoresis. Using thin-layer Sephadex immunochromatography, the molecular weights of 18 cytoplasmic immunogens were determined and found to range from 16 460 to 291 230. Analytical isoelectric focusing resolved the constituent proteins into at least 30 bands, most with isoelectric points in the pH range 3·5–6·1. The most anodic band was found to be a glycoprotein. The soluble antigens were resolved, by DEAE-Sephacel chromatography, into nine fractions with variable antigenic activity. Fraction 1 contained nearly all of the antigenic activity that could be detected by the double antibody sandwich method; fraction 2 contained most of the immunogens which stimulate precipitin antibodies.

Generation of hybridoma cell lines producing monoclonal antibodies against Toxoplasma gondii or rabies virus following fusion of in in vitro-immunized spleen cells with myeloma cells

The present experiments proved that specific antibody against Toxoplasma gondii or rabies virus (RV) could be induced in vitro in spleen cells from normal (i.e. not deliberately immunized) mice following seven days exposure to the relevant antigen presented in association with syngeneic macrophages. Using such in vitro-primed spleen cells as fusion partners with non-secretor myeloma cells, we were able to isolate hybridomas secreting anti-toxoplasma or anti-RV antibody with high frequency. A total of 12 cloned continuously propagable hybridoma lines were established, which secreted T. gondii-specific antibodies; 9 of the antibodies were directed against trophozoite membrane-associated antigen(s) and the remaining 3 could recognize soluble cytoplasmic antigen(s). Among the panel of 9 clonal antibodies reacting with trophozoite membrane antigen(s), only 4 showed reactivity in the Sabin-Feldmann dye test (complement-dependent cytotoxicity test). Fifteen stable cloned hybridomas obtained from fusions between myeloma cells and spleen cells primed in vitro against RV secreted antibodies which reacted with intact RV in radioimmunoassay. Since 10 of these 15 different hybridoma-derived antibodies could neutralize RV and also stained the membranes of RV-infected cells in the indirect immunofluorescence test, it can be postulated that they were directed against the coat glycoprotein (G-protein) of RV. The remaining 5 monoclonal antibodies which failed to neutralize RV stained the intracytoplasmic inclusions exclusively. This suggests that they may be recognizing the RV nucleocapsid determinant(s). Immunochemically, 17 monoclonal antibodies obtained in the present study (7 against T. gondii and 10 against RV) were of IgM class, 3 antibodies (2 against T. gondii and 1 against RV) were of IgG1 subclass and 7(3 against T. gondii and 4 against RV) were of IgG2a subclass. The continuously propagable hybridomas established in the present study provide a useful source of large quantities of homogeneous antibodies specific for T. gondii and RV.

Deposition of antibodies to a soluble cytoplasmic antigen in the kidneys of patients with systemic lupus erythematosus.

Two patients with systemic lupus erythematosus were studied whose sera contained precipitating antibodies to a soluble cytoplasmic antigen, termed Ro. A reduction in the amount of these antibodies in each case was accompanied by a deterioration in the clinical status with the development of nephritis leading to death. Acid elution of gamma globulin was performed from homogenates of the renal cortex, and in both instances antibodies to Ro were demonstrated in the eluates by double immunodiffusion. The titer of these antibodies was measured in both sera and eluates, and specific enrichment of anti-Ro in the eluates was demonstrated in both patients. This strongly suggests the direct participation of Ro-anti-Ro immune complexes in the progressive renal disease and may underlie the association seen here between the decreasing serum titers of antibodies to Ro and the clinical deterioration in these two cases.

Antibodies to cytoplasmic antigens in lupus erythematosus

Seven patients with classic cutaneous lupus erythematosus are described. Three of these patients had features satisfying four of the American Rheumatism Association (ARA) preliminary criteria for the diagnosis of systemic lupus erythematosus (SLE). Their sera, however, lacked antinuclear antibodies but demonstrated precipitating antibodies reactive against cytoplasmic RNP (La) and non-nucleic acid (Ro) antigens. Four additional ANA-negative patients lacking significant skin disease but having a lupus-like multisystem disease were found to have antibodies to soluble cytoplasmic antigens. Thirty-three of 130 ANA-positive SLE patients, but none of 16 discoid lupus patients, possessed these anticytoplasmic antibodies. These findings suggest that antibodies to Ro and La may be a marker for systemic disease in ANA-negative patients with 1) cutaneous lupus and 2) a distinct subpopulation of patients with a lupus-like syndrome without skin disease.

Cytotoxic and stimulatory effects of antisera to membrane associated antigens of lymphocytes.

Antisera against subcellular rat lymphocyte fractions, an unfractionated lymphocyte homogenate, a purified microsomal fraction and a soluble cytoplasmic fraction were produced in rabbits. The highly cytotoxic antisera against the microsomal fraction exhibited only a low stimulatory activity. The antisera against the cytoplasmic fraction were less cytotoxic, but stimulated the DNA-synthesis in rat lymphocyte cultures very effectively. Antisera against the ULH showed high cytotoxic titers and strong stimulatory properties. The cytotoxic activity could be removed by absorption with the ULH and the microsomal fraction; the stimulatory activity was reduced only by absorption with the ULH. Absorption with the cytoplasmic fraction was ineffective. In immunofluorescence studies and with the immunoferritin technique it could be demonstrated that the microsomal as well as the soluble cytoplasmic antigen is a constituent of the lymphocyte surface membrane which is distributed in patches on the membrane in different patterns. The immunofluorescence studies indicate that thymus cells lack some antigenic determinants which are present on membranes of lymph node and spleen cells.

Characterization of a Soluble Cytoplasmic Antigen Reactive with Sera from Patients with Systemic Lupus Erythmatosus

Summary A tissue antigen reactive with sera from SLE patients has been partially characterized. The antigen is a soluble cytoplasmic component which is present in a variety of human tissues and is distinct from known nuclear antigens. It is an acidic macromolecule which has the electrophoretic mobility of an α1 globulin and is resistant to most proteolytic enzymes including trypsin, pepsin and chymotrypsin. Antigenicity is destroyed by 0.02 M periodate and by 0.001 M parahydroxy mercuribenzoate. Antibodies to this antigen have been found in 40% of unselected LE sera and were absent from a large number of sera from normal persons and from the sera of patients with other connective tissue disorders.