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D Pressman

Publications and source records attributed to D Pressman.

At least 37 records · Page 2Linked to original sources

Comparison of the homogeneous, primary anti-dextran B1355 antibody raised in BALB/c mice with protein 104E.

The primary antibody response to dextran B1355 in BALB/c mice is largely a homogenous IgM antibody. This antibody appears to be similar if not identical to the myeloma protein, protein 104E, for the following reasons: a) isoelectric focusing of the 7S monomers, separately and together in co-isoelectric focusing, give the same pattern, both in the presence and absence of 4M urea; b) the inhibition of lysis of the dextran-coated SRBC by specifically purified anti-dextran antibody and by protein 104E required essentially the same concentration of dextran B1355. This similarity was further demonstrated by plaque assays with dextran-coated SRBC, in which the formation of plaques was inhibited by free dextran. Inhibition of plaques produced by both types of cells required essentially the same concentration of dextran B1355. On these bases, there appears to be no difference in properties (or in structure) between the myeloma protein and the induced antibody.

Animals

Rabbit antiserum against a non-T, non-B leukemia cell line that carries the Ph1 chromosome (NALM-1): antibody specific to a non-T, non-B acute lymphoblastic leukemia antigen.

Rabbit immune sera against human cells of a non-T, non-B leukemia cell line bearing the Ph1 chromosome (NALM-1) were characterized. After proper and exhaustive absorption, the sera were tested by indirect membrane immunofluorescence on a panel of 19 human hematopoietic cell lines with T-, B-, or non-T, non-B cell surface characteristics. The absorbed sera reacted specifically with NALM-1 cells but not with cells of another Ph1-positive cell line, K-562. Four of the 6 leukemia T-cell lines, 2 of the 4 leukemia-lymphoma B-cell lines, all of 4 acute lymphoblastic leukemia (ALL) lines with non-T, non-B cell characteristics, and uncultured cells of all patients with non-T, non-B cell ALL were reactive with the antisera. A cross-absorption study of the antisera suggested that a single antigenic complex is involved in this antigen specificity. The antigen involved appears to be a common non-T, non-B ALL one that has been described previously.

Animals

Radioimmunoassay for myeloma idiotype.

Rabbit anti-idiotype antisera were prepared against four human myeloma proteins. These antisera demonstrated a capacity to bind the 125I-labeled autologous purified monoclonal IgG, but failed to demonstrate any binding to 125I-labeled normal IgG or to labeled myeloma IgG obtained from other myeloma patients. The anti-idiotypic antisera were used with 125I-labeled autologous myeloma IgG preparations and goat antirabbit IgG for specific radioimmunoassay with a sensitivity limit of 20 ng/ml. Little or no cross-reaction occurred between these anti-idiotypic antisera and normal IgG preparations or other myeloma IgG proteins.

Antibodies, Anti-Idiotypic

Syngeneic tumor rejection induced by immunization with normal allogeneic tissues.

Immunization with normal allogeneic kidney and liver tissues extends survival of DBA/2Cr mice challenged with a lethal dose of syngeneic L517BY lymphoma cells. Immunization with a combination of tissues from five strains provides far more protection than immunization with tissue from any single strain. It is suggested that the basis of this protective effect is a cross-reactivity or identity between tumor-associated transplantation antigens (TATA) on the L5178Y tumor and non-H-2 alloantigens normally expressed by some allogeneic tissues.

Animals

Protection against syngeneic tumor grafts induced by inoculation with normal allogeneic tissues.

Subcutaneous injection of normal allogeneic kidney and liver tissues extended survival of DBA/2Cr mice challenged with a lethal dose of syngeneic L5178Y lymphoma cells. Immunization with a combination of tissues from five strains provided far more protection than immunization with tissue from any single strain. It is suggested that the basis of this protective effect is a cross-reactivity or identity between tumor-associated transplantation antigens (TATA) on the L5178Y tumor and non-H-2 alloantigens normally expressed by some allogeneic tissues.

Animals

Mechanisms of B cell tolerance. I. Tolerance to dextran B1355 induced with the oxidized dextran.

The bacterial dextran B1355, which is normally a potent thymus-independent immunogen, was made tolerogenic by oxidation. The injection of the oxidized dextran into BALB/c mice before, at the same time, or up to 4 days after the injection of the immunogenic form of the dextran resulted in a marked immunologically specific suppression of the number of anti-dextran antibody-forming cells found in the spleen. This suppression resulted from a direct inactivation of antibody-forming cell precursors rather than from either inhibition of antibody secretion or the exhaustive utilization of precursor B cells that have been observed in other tolerance systems. A substantial degree of tolerance was achieved after only a 1-hr in vivo exposure of the spleen cells to the tolerogen. At a dose of 1 mg of oxidized dextran per mouse, tolerance persised for at least 3 weeks. A complete recovery was apparent by 10 weeks. The stability of the tolerance was demonstrated by transferring tolerant spleen cells to irradiated recipients. The response in the recipient animals to an immunogenic dextran challenge remained suppressed. It appears that the tolerogenicity of the oxidized dextran is due to its ability to couple covalently with free amino groups in or near the receptor site of the cell membrane via the reactive dialdehyde groups of the dextran.

Animals

Differential tumor immunogenicity of L1210 and its sublines. I. Effect of an increased antigen density on tumor cell surfaces on primary B cell responses in vitro.

The differential immunogenicity of DBA/2 lymphoma L1210 and three L1210 sublines, each resistant to a different anti-leukemic agent (guanazole, methylglyoxal-bis-guanylhydrazone, and 4,4-diacetyldiphenylurea-bis-guanylhydrazone), was evaluated in vitro. Syngeneic spleen cells from nonimmunized DBA/2 mice were cultured in the presence of graded numbers of irradiated cells of L1210 or its sublines. The stimulation elicited a T-independent primary antibody response in vitro which was measured by determining the number of plaque-forming cells by using the immunizing lymphoma cells as target. Cells of all three sublines exhibited an increased immunogenicity, as compared to that of the parental L1210 cells, in eliciting the response directed to tumor-associated antigens which were common to all sublines. Dose-response experiments showed that high doses of the parental cells did stimulate responses which were detectable with subline cells as target. The results indicated that the differential immunogenicity of L1210 and its sublines, as demonstrated in the present assay system, is primarily quantitative, and was apparently due to increased amount or density of common tumor-associated antigens on the subline cells. The implications of these observations are discussed in relation to the possible mechanisms underlying the emergence of highly immunogenic drug-resistant sublines.

Animals

Common antigenic structures of HLA antigens. VII. Selective combination binding of beta2-microglobulin with HLA large component in cultured human cell lines.

The intracellular distribution of human beta2-microglobulin was examined in human cell lines (a Burkitt lymphoma cell line, a B-lymphoid cell line and an epighelial-like cell line). Freshly harvested cells were mechanically disrupted and separated into the nuclear, cell-membrane and cell-sap fractions. Nearly 90 per cent of the total beta2-microglobulin was recovered in the cell-membrane and cell-sap fractions. The cell-membrane fraction contained 75-88 per cent of the beta2-microglobulin recovered. The rest was in the cell-sap fraction. Most, 84-91 per cent, of the beta2-microglobulin in the cell-membrane fraction was present combined with membrane fraction was present combined with membrane components of about 38,000 daltons that carried the xenoantigenic activity characteristic of the HLA large component. These membrane components did carry HLA alloantigenic activity. No other membrane components were involved in binding beta2-microglobulin. The beta2-microglobulin in the cell-sap fraction was present in the unbound state. Thus, in the cell lines examined, the membrane component which was combined with beta2-microglobulin appeared to be exclusively the HLA large component and no larg excess of beta2-microglobulin over the HLA large component was found.

Beta-Globulins