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J Rauch

Publications and source records attributed to J Rauch.

At least 91 records · Page 5Linked to original sources

Shared idiotypes are expressed on mouse and human anti-DNA autoantibodies.

The expression of common idiotypes on human and mouse anti-DNA monoclonal autoantibodies made by hybridomas was examined by their competitive binding to anti-idiotype antibodies. Some murine autoantibodies inhibited the binding of a human anti-DNA autoantibody 16/6 to monoclonal or polyclonal anti-idiotypic antibodies. Another human antibody (134) was not inhibited in its binding to homologous anti-idiotypic antibodies. The expression of the human 16/6 idiotype on mouse antibodies was restricted to those that had a specificity similar to the 16/6 antibody itself, their major properties being that they reacted more strongly with single stranded DNA (ssDNA) than double stranded DNA (dsDNA). One mouse antibody expressing the 16/6 idiotype also bound weakly to RNA. The results imply structural similarities between the binding sites of the antibodies in the two species, and are consistent with evolutionary conservation of V genes coding for primitive ancestral antibodies that react with DNA and become diversified through somatic mutation.

Animals↗

Hybridoma anti-DNA autoantibodies from patients with rheumatoid arthritis and systemic lupus erythematosus demonstrate similar nucleic acid binding characteristics.

Hybridoma anti-DNA antibodies have been generated from the fusion of the GM 4672 lymphoblastoid line with peripheral blood lymphocytes from four normal subjects, nine patients with rheumatoid arthritis (RA), and 13 patients with systemic lupus erythematosus (SLE). A total of 441 hybridoma clones were obtained, of which 37 secreted anti-DNA autoantibodies. The nucleic acid binding characteristics of the anti-DNA antibodies produced by two hybridomas from normal subjects, nine hybridomas from RA patients, and 18 hybridomas from SLE patients are reported. The hybridoma anti-DNA antibodies from all three groups showed similar antigen-binding characteristics for denatured DNA (dDNA), native DNA (nDNA), poly(I), poly(dT), and cardiolipin, by both direct binding and competitive binding analyses. One difference noted between normal-derived anti-DNA antibodies and autoimmune-derived antibodies was the inability of the former to react with z-DNA. However, this requires further substantiation with larger numbers of normal-derived clones. The broad overlap of reactivity to nucleic acid antigens among individual anti-DNA autoantibodies found in two clinically different autoimmune diseases, namely RA and SLE, suggests that the pathogenicity of anti-DNA autoantibodies may bear no relationship to their nucleic acid antigen-binding characteristics.

Adult↗

Sensitive solid phase radioimmunoassay for the detection of anti-DNA autoantibodies.

Serum from patients with systemic lupus erythematosus (SLE) and hybridoma culture fluids derived from the fusion of SLE lymphocytes contain antibodies to native DNA (nDNA) and denatured DNA (dDNA). A rapid, efficient solid phase radioimmunoassay (RIA) was developed to screen for minute quantities of these autoantibodies. The RIA, which utilized polystyrene tubes, required the addition of 0.1% bovine serum albumin and 0.01% Tween 20 detergent to decrease nonspecific immunoglobulin binding. Pretreatment of the polystyrene tubes with poly-L-lysine (PLL) prior to coating with DNA increased the binding of radiolabeled nDNA from 15 to 46% and of dDNA from 17 to 63%. This PLL precoating step resulted in a 3-fold increase in the specificity of the assay for nDNA but was not advantageous for dDNA. The method described is sensitive, specific, and can be applied to the screening of microgram quantities of anti-DNA autoantibodies in serum and hybridoma culture fluids.

Antibodies, Monoclonal↗

Anti-DNA antibody idiotypes in systemic lupus erythematosus.

Monoclonal anti-DNA antibodies prepared by the hybridoma technique were used for an analysis of idiotypes of anti-DNA antibodies in systemic lupus erythematosus (SLE). Serum levels of one idiotypic marker, 16/6/R, were higher than normal in 40 of 74 patients (54%) with active SLE, compared with only 6 of 24 patients (25%) with inactive SLE, 9 of 38 patients (25%) with rheumatoid arthritis, and 4 of 96 normal subjects (4%). Levels of the 16/6/R idiotypic marker were determined in serially collected serum samples from 12 patients with SLE. Concordance was found between idiotype levels and clinical activity in 8 of the 12 patients. Levels of the 16/6/R idiotype tended to correlate with levels of antibodies to double-stranded DNA, but in some cases the clinical status was reflected better by the idiotype levels than by the levels of anti-double-stranded-DNA antibodies. Measurement of idiotypes of anti-DNA antibodies may provide information valuable in monitoring the clinical course of patients with SLE.

Antibodies, Monoclonal↗

Monoclonal anti-cardiolipin antibodies bind to DNA.

BALB/c mice immunized with the phospholipid, cardiolipin, produced anti-cardiolipin and anti-DNA antibodies. Seven hybridomas derived from spleen cells of the cardiolipin-immunized mice produced cardiolipin-binding monoclonal antibodies that also bound to the polynucleotides DNA, poly(dT), and poly(I). The seven cardiolipin-induced monoclonal antibodies shared idiotypic determinants with a high frequency idiotypic marker of spontaneously expressed anti-DNA autoantibodies of lupus-prone MRL-lpr/lpr mice. The monoclonal antibodies presumably bound to phosphodiester phosphate groups that occur in both polynucleotides and phospholipids. The results imply that production of anti-DNA autoantibodies does not require immunization by DNA.

Animals↗

Influence of fusion cell ratio and cell plating density on production of human-human hybridomas secreting anti-DNA autoantibodies from patients with systemic lupus erythematosus.

The utilization of one human lymphoblastoid cell line in fusion experiments with peripheral blood lymphocytes from patients with systemic lupus erythematosus (SLE) has made it possible to define efficient and reproducible conditions for the production of anti-DNA-secreting human-human hybridomas. This investigation, using the human lymphoblastoid cell line GM 4672 fused in the presence of 44% polyethylene glycol with lymphocytes from SLE patients, demonstrated a maximal yield of 22.8% hybridomas, 17% of which produced anti-DNA antibodies. We were able to define, in two independent laboratories, that the maximal yield of hybridomas occurred when the lymphocyte to GM 4672 cell ratio was 1:1 and cells were seeded in 2.0 ml wells at a concentration of 4 X 10(5) cells/well. This report demonstrates the reproducibility of human-human hybridoma production with the GM 4672 cell line and the establishment of efficient conditions for the production of anti-DNA autoantibodies from SLE patients.

Autoantibodies↗

In vivo effects of antibodies against a high frequency idiotype of anti-DNA antibodies in MRL mice.

The in vivo effects of a rabbit antiserum against the dominant idiotype of MRL-lpr/lpr anti-DNA antibodies (termed H130) were studied in MRL-lpr/lpr, MRL/++, and BALB/c mice. Under the conditions we examined, the anti-idiotype did not suppress anti-DNA antibodies or the H130 idiotype in either MRL-lpr/lpr or MRL/++ mice. By contrast, MRL/++ and BALB/c mice responded to the antiserum by producing antibodies with the H130 idiotype. The increase in levels of the idiotype was accompanied by a rise in anti-DNA antibodies only when F(ab')2 fragments of the rabbit antiserum were administered. Only about 10% of the induced H130+ immunoglobulins were anti-DNA antibodies. An immunoregulatory disturbance in MRL-lpr/lpr mice may account for their resistance to anti-idiotypic antibodies. Treatment of autoimmune diseases with anti-idiotypes may have the undesired effect of augmenting the production of autoantibodies.

Animals↗

Idiotypic cross-reactions of monoclonal human lupus autoantibodies.

Idiotypic cross-reactions were evaluated in 60 polynucleotide-binding monoclonal lupus autoantibodies produced by human-human hybridomas that were derived from seven unrelated patients with SLE. Three antiidiotype reagents were prepared by immunization of rabbits or a mouse with monoclonal autoantibodies from two patients. Binding of the three reagents to their corresponding idiotypes was inhibited by one or more polynucleotides, an indication that the antiidiotypes reacted with the variable regions of the autoantibodies. Each antiidiotype appeared to detect a different idiotypic determinant. Of the 60 monoclonal autoantibodies tested, 40 reacted in one or more competitive immunoassays; 15 reacted with one antiidiotype, 10 reacted with two antiidiotypes and 15 reacted with three antiidiotypes. A monoclonal antiidiotype reagent cross-reacted with autoantibodies from six of the seven patients. The idiotypic cross-reactions of immunoglobulins from unrelated patients suggest that the autoantibodies are derived from related families of germ line genes that are expressed by patients with SLE.

Animals↗

Polyspecificity of monoclonal lupus autoantibodies produced by human-human hybridomas.

We studied the serologic properties of monoclonal autoantibodies that were produced by hybridomas derived from lymphocytes of patients with systemic lupus erythematosus. The hybridomas were made by fusion of a human lymphoblastoid cell line, GM 4672 (derived from a patient with multiple myeloma), with peripheral-blood or splenic lymphocytes from six patients with lupus. Thirty monoclonal autoantibodies, selected for their ability to react with denatured DNA, were analyzed. Eighteen of them reacted with three or more additional polynucleotides, including native DNA, left-handed double-helical DNA (Z-DNA), poly(l), and poly(dT). Ten reacted both with nucleic acids and the phospholipid cardiolipin. The multiple binding reactions of the monoclonal autoantibodies may be explained by the presence of appropriately spaced phosphodiester groups in both the polynucleotides and the phospholipid. The sharing of antigenic groups by polymers of different natures may contribute to the apparent diversity of serologic reactions in systemic lupus erythematosus. These findings suggest that DNA itself need not be the immunogenic stimulus for autoantibody formation in this disease.

Adult↗

A high frequency idiotypic marker of anti-DNA autoantibodies in MRL-Ipr/Ipr mice.

Anti-idiotypic antibodies were used to analyze relatedness of anti-DNA autoantibodies of MRL mice. The antiidiotypic antibodies, produced by immunization of rabbits with MRL-Ipr-derived hybridoma anti-DNA antibodies, were defined by their ability to inhibit specifically the binding of hybridoma anti-DNA antibody to DNA. One monoclonal anti-DNA antibody, H130, cross-reacted with two thirds of other hybridoma anti-DNA antibodies. The H130/anti-H130 system detected high amounts (up to 5 mg/ml) of immunoreactivity in sera of MRL-Ipr mice, whereas levels in MRL-+ sera were relatively low. The H130 family increased 10-fold in MRL-Ipr mice over the course of 5 mo, but its levels did not correlate chronologically with those of anti-DNA antibodies, cardiolipin-binding antibodies, or total serum immunoglobulins. H130 cross-reactivity was found, by quantitative immunoadsorption, in 40 to 60% of serum anti-DNA antibodies; however, a large excess of H130-related serum antibodies did not bind to DNA. The H130 family and anti-DNA antibodies therefore seem to constitute overlapping populations.

Aging↗

Polyspecific monoclonal lupus autoantibodies reactive with both polynucleotides and phospholipids.

Hybridomas the produce anti-DNA autoantibodies were prepared from spleen cells of unimmunized MRL/1 mice, a strain that spontaneously develops severe systemic lupus erythematous (SLE). Reactivities of these monoclonal antibodies with a wide range of polynucleotides prompted tests of their reactions with phospholipids which, like polynucleotides, contain diester-linked phosphate groups in their backbones. In competitive radioimmunoassays, cardiolipin, phosphatidic acid, and phosphatidyl glycerol blocked the binding of these hybridoma antibodies to denatured DNA. These phospholipids also specifically inhibited the reaction between a hybridoma antibody and a site-specific anti-idiotypic antibody. The antinuclear reaction of one of these antibodies was specifically inhibited by cardiolipin. This same antibody prolonged the activated partial thromboplastin time in a manner characteristic of a lupus anticoagulant, presumably by binding to phospholipid in the test system. The polyspecific reactivity of a single molecular species of lupus autoantibody suggests that some of the diverse serological abnormalities of SLE may be a result of the binding of certain autoantibodies to a phosphodiester-containing epitope that is present in diverse biological molecules.

Animals↗

Antigen-binding diversity and idiotypic cross-reactions among hybridoma autoantibodies to DNA.

Hybridoma anti-DNA antibodies produced by clones derived from fusions of spleen cells from unimmunized MRL/l mice with BALB/c plasmacytomas were examined for their binding to nucleic acid antigens and for their reactivities with anti-idiotype antibodies. All the antibodies bound to a variety of nucleic acids and polynucleotides. This finding suggests that epitopes shared by nucleic acid antigens can account for some of the serologic diversity in lupus serum. Each hybridoma autoantibody had a unique pattern of reactivity with nuclei acid antigens, yet cross-reactions among some of them were found by analyses with anti-idiotype antibodies. These cross-reactions were due to similarities in the antigen-binding regions of the autoantibodies because anti-idiotype Ig blocked the binding of the hybridoma antibody DNA; moreover, polynucleotides inhibited the idiotype anti-idiotype reaction. Cross-reactive idiotypes were found not only among hybridoma anti-DNA antibodies produced by clones derived from the same MRL/l mice but also among antibodies produced by clones derived from different MRL/l mice. The latter finding suggests that families of germ line genes may encode some autoantibodies against DNA.

Animals↗