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D N Misra

Publications and source records attributed to D N Misra.

At least 55 records · Page 3Linked to original sources
PubMed1984

Elicitation of the maternal antibody response to the fetus by a broadly shared MHC class I antigenic determinant.

The antibody response to the semiallogeneic fetus in the rat was examined in eight mating combinations that were chosen specifically to cross different major histocompatibility complex (MHC) and nonMHC loci. The BN X DA and BN X BN.1A(DA) matings (n anti-a) were the only ones to show an antibody response to the fetus, and the response occurred in 25-64% of the matings. All the other six mating combinations studied were negative by hemagglutination, cytotoxicity, and cellular radioimmunoassay. The response appeared in the postpartum period after the first litter and reached its maximal frequency during the postpartum periods of the second and third matings. There was no correlation between the litter size and the presence or absence of an antibody response to the fetal antigens. The antibodies elicited by the fetus were hemagglutinating but not cytotoxic, and consisted of only one isotype, IgG2a, whereas in the alloantiserum raised by skin grafting and the injection of lymphocytes, they were distributed among the IgG2a greater than IgG1 greater than IgM isotypes and were both hemagglutinating and cytotoxic. Using reciprocal congenic strains, the pregnancy-induced antibody response was shown to be against MHC antigens only. This finding was confirmed by testing the sera against rats from a population that was segregating for the haplotypes a/a, a/n, and n/n. Comparison of the pregnancy-induced antibody with the BN anti-DA alloantibodies by absorption studies showed that the former was less crossreactive, did not react with the RT1.Aa haplotype-specific antigenic determinant, and did react with an antigenic determinant shared among the a, d, o, i, e, f, r10, b, and m haplotypes--but not with the n, c, g, k, l, h, or u haplotypes. Using the DA.1I and r10 strains in cellular radioimmunoassay, absorption, and immunoprecipitation experiments, it was shown that the pregnancy-induced antibody was elicited by a class I antigenic determinant, provisionally designated Pa, which is encoded by a locus in the vicinity of RT1.A.

Animals↗
PubMed1983

Immunochemical evidence for multiple class I antigens coded by the MHC of the rat (RT1) and their differential expression on red blood cells and lymphocytes.

Five monoclonal antibodies reacting with class I MHC antigens were produced by fusing lymphocytes from WF (RT1u) rats immunized against DA (RT1a) rats with P3-X63-Ag8.653 myeloma cells. Sequential immunoprecipitation studies with the mAb and the WF anti-DA alloantiserum demonstrated the presence of four different class I molecules: all four molecules were reactive with the alloantiserum; three of them contained the determinant for mAb 155; two of the latter three molecules shared the determinants for mAb 3, 56 and 60, and one of these two molecules also contained the determinant for mAb 118. The four molecules could be isolated from the antigen preparation by sequential immunodepletion first with 118, next with 3, then with 115 and finally with the alloantiserum or by sequential absorption with affinity columns of Sepharose 4B coupled to the antibodies. The three antigens which were sequentially isolated with the mAb 118, 3, and 155, respectively, were analysed by SDS-PAGE after digestion with Staphylococcus aureus V8 protease, and they showed differences in peptide patterns. The relative amounts of the antigens expressed on red blood cells and on lymphocytes were different based on the results of sequential isolation and indirect cellular radioimmunoassay: the antigen which reacted with both mAb 3 (and 56 or 60) and 155 was the major class I antigen on red blood cells, and the antigen which reacted with mAb 118, 3 (and 56 or 60) and 155 was the major class I antigen on lymphocytes.

Animals↗
PubMed1982

Growth of rat-mouse hybridomas in nude mice and nude rats.

Athymic (nude) mice and rats were inoculated intraperitoneally with rat-mouse hybridoma cells secreting monoclonal antibodies to rat MHC class I antigens in order to improve the yield of antibodies. Pristane priming and subsequent intraperitoneal injection of the hybridoma cells in to nude mice yielded ascites which contained antibody in high concentration (10-15 mg/ml). Complete Freund's adjuvant, mineral oil, pristane or antibody-antigen complexes were used to induce ascites in nude rats, but only pristane priming did so consistently. The hybridoma cells in the ascitic fluid failed to secrete antibody, although they contained intracellular antibody. However, when the pristane-primed nude rats received 250-500 rads of total body radiation prior to injection with the hybridoma cells, they produced large amounts of antibody. When the nude rats were splenectomized and injected with the hybridoma cells, they also produced antibody in high titers. There was no in vitro inhibition of antibody formation by the hybridoma cells cultured in medium containing 15% serum from nude rats, but co-culture of the hybridoma cells with splenic lymphocytes from normal or nude rats markedly inhibited antibody production. These results indicate that the defect in antibody secretion by the hybridoma cells in the ascites of nude rats is due to the presence of radiation-sensitive suppressor cells in the spleen.

Animals↗
PubMed1982

The identification and mapping of a second class I locus in the major histocompatibility complex of the rat.

A combined genetic, serologic, and biochemical study has demonstrated the existence of a second locus, RT1.E, that codes for class I antigens in the major histocompatibility complex (MHC) of the rat, and has mapped it relative to the other loci in the MHC. The evidence was obtained with the use of two laboratory-derived recombinants, r10 and r11, and the congenic strains DA.1I and BN.1I. Antibodies raised against the i haplotype (RT1.AnBa) in strain combinations that were matched for their RT1.A and RT1.B loci and in the BY1 and anti-r11 strain combination, in which the RT1.A and RT1.B loci and many of the non-MHC genes were matched, reacted with red blood cells and lymphocytes carrying the u haplotype. Immunoprecipitation showed that these antisera reacted specifically with a component of red blood cell membranes having a m.w. of 45,000. Mapping studies place the genes in the rat MHC in the order RT1.ABE; hence, the organization of the MHC in the rat appears to be similar to that of the mouse.

Animals↗
PubMed1981

Adsorption of N-(2-hydroxy-3-methacryloxypropyl)-N-phenylglycine (NPG-GMA) on cupric ion-enriched hydroxyapatite surface to improve chemical bonding between dental resins and teeth.

In continued studies of chemical bonding between a polymer and teeth through the mediation of coupling agents, the absorption of N-(2-hydroxy-3-methacryloxypropyl)-N-phenylglycine (NPG-GMA) from ethanol solution was studied on cupric ion-treated synthetic hydroxyapatite in order to discriminate the adsorptive behaviour of the 'mordanted' as against the unmordanted (or pure) apatite. All features of the adsorption isotherm, however, agree with those of the isotherm obtained on pure hydroxyapatite. Also, polymer filled with cupric ion-treated hydroxyapatite coated with the irreversibly adsorbed NPG-GMA has a tensile strength comparable to that of the polymer filled with NPG-GMA coated pure hydroxyapatite.

Acrylates↗
PubMed1981

Adsorptive bonding to hydroxyapatite I: adsorption of anthranilic acid - the effect of solvents. Search for surface bonding groups for coupling agents to teeth.

A study was initiated to explore the nature of surface-active groups of model compounds that might cause chemisorption of comonomers used in the polymerization of dental resins on hydroxyapatite (the main constituent of bone) and thus effect a strong and durable bond between the resins and hard tooth tissues. In an effort to accomplish this objective, adsorption of anthranilic acid on hydroxyapatite was studied from three solvents: 95% aq. ethanol, dimethyl sulphoxide and methylene chloride. The adsorption is reversible from the first two solvents and the isotherms follow Langmuir plots. Adsorption is irreversible from methylene chloride; a constant amount of adsorbate is removed from different solutions above a certain threshold concentration but all adsorbate is removed from solutions below this threshold concentration. The saturation amounts obtained from the two Langmuir plots and the maximum irreversibly adsorbed amount in the above three solvents are 11.4, 6.0 and 17.2 mmol/100 g, respectively. These, together with the surface area (41.0 m2/g; BET, N2) of the hydroxyapatite, yield the effective molecular areas of 60, 114, and 40 A2, respectively. These areas can be matched, on geometrical considerations, with areas of 60, 110, and 40 A2 of the model adsorbate molecule rotating about; (i) its centre, lying flat on the surface, (ii) its carboxyl group at 45 degrees to the surface, and (iii) the carboxyl group in an upright position, respectively.

Adsorption↗
PubMed1981

Characterization of the RT2 antigens of the rat erythrocyte membrane.

Haemagglutination inhibition studies using isolated membrane components from rat red blood cells showed that the activity of the major antigenic system RT2 was contained exclusively in the glycoprotein fraction and confirmed immunochemically the existence of two alleles, RT2 a and RT2 b. The SDS-PAGE analysis of the membrane showed two interconvertible glycoproteins of apparent molecular weight 72,000 and 36,000, and the higher molecular weight component appeared to be a dimer of the lower molecular weight one. Analysis of the various membrane preparations after 125I-labelling showed that the glycoproteins existed in at least two molecular species on the surface of the red cells and that one species was more readily radio-iodinated and dimerized than the other. The RT2 antigenic specificities were preferentially associated with this component.

Animals↗
PubMed1980

Alterations in glycoproteins and lipids in azaserine-induced acinar cell carcinoma of rat pancreas.

Glycoproteins and lipids of rat pancreatic acinar cell carcinomas maintained in nude mice and in cell culture, were analyzed. The tumor contained significantly elevated levels of glycoproteins when compared with their normal counterparts. SDS-PAGE of tumor glycoproteins revealed that there were increased amounts of small molecular weight glycoproteins and the tumor also contained a 51,000 dalton glycoprotein which was not detected in the pancreas, liver or the sera of the control animals. The tumor in nude mice and cancer cells in culture had decreased lecithins and triglycerides, and increased amounts of free fatty acids, and both free and esterified cholesterols. The results indicate that altered glycoprotein and lipid compositions represent some of the characteristic features of the acinar cell carcinoma.

Animals↗
PubMed1980

Characterization of the T antigen and T agglutinin in inbred rats.

Treatment of rat erythrocytes with vibrio cholerae neuraminidase (VCN) exposed antigenic determinants on the cell surface membrane, and autologous rat serum contained antibodies which reacted with these determinants and with VCN-treated human erythrocytes. The antibodies were not present in sera of animals less than 8 weeks of age. Human serum also contained antibodies which reacted with the VCN-treated rat erythrocytes. Lectin isolated and purified from Arachis hypogoea agglutinated VCN-treated rat erythrocytes. This system has the characteristics of the T antigen which had been described initially in humans. Absorption studies showed that the VCN-treated rat erythrocyte membrane antigen cross-reacted with the VCN-treated human erythrocyte membrane antigen. Absorption of rat sera and the lectin solution with VCN-treated rat or human erythrocytes removed all of the molecules capable of reacting with both rat and human erythrocytes. Absorption of human sera with VCN-treated human cells removed their reactivity with both cell types, but absorption with VCN-treated rat cells did not remove completely their reactivity with VCN-treated human erythrocytes. These results indicate that the VCN-treated rat cells contain antigenic determinants which are identical to some on the VCN-treated human cells and that the human sera contain antibodies to additional antigenic specificities not shared with rat red blood cells. Haemagglutination inhibition studies with different sugars, T antigen from human erythrocyte membranes and desialylated glycoprotein from rat erythrocyte membranes showed that the T antigen, the desialylated glycoprotein and the sugars containing a terminal non-reducing beta-D-galactosyl residue inhibited the reactivity of the lectin, the rat sera and the human sera with both human and rat red blood cells. These findings show that the antigenic reactivity of the VCN-treated rat red blood cells residues in the membrane glycoproteins and that the immunodominant group is a carbohydrate. Thus, the rat has a T antigenic system very similar to that of the human.

Absorption↗
PubMed1978

Surface area of dental enamel, bone, and hydroxyapatite: chemisorption from solution.

The surface areas of three different samples of hydroxyapatite, samples of deproteinized bone, and samples of whole and deproteinized enamel were determined by adsorption of an adduct (the diglycidyl ether of bisphenol A with N-phe-nylglycine) from methylene chloride solution. In all cases, the surface areas of these samples agree well with those obtained by the BET (N2) method.

Adsorption↗
PubMed1978

Lymphocyte plasma membranes. VI. Plasma membrane glycoproteins of thymic and splenic lymphocytes from inbred rats.

Plasma membranes of splenic and thymic lymphocytes from ACI rats were analyzed for their protein and glycoprotein components by surface radioiodination with 125I and SDS-polyacrylamide gel electrophoresis. The glycoproteins were extracted with lithium diiodosalicylate, characterized and assayed with antisera to thymic antigen. Plasma membranes of both cell types showed more than 25 proteins of which 10--15 were glycoproteins. Both cells showed five major glycoproteins but their apparent molecular weights or intensities differed. Surface radioiodination showed a 120 000 daltons component, common to both cell types, and a 27 000 daltons thymus-specific component as the most exposed surface glycoproteins. Lithium diiodosalicylate extracts of the plasma membranes contained almost all of the glycoprotein components and comprised 5-6 percent of the total membrane protein and 40-50 percent of the total membrane carbohydrate, with sialic acid content in thymus twice that of the spleen cells. About 1 percent of the total plasma membrane protein and 7 percent of the total isolated glycoproteins from thymocytes were reactive with rabbit anti-rat thymocyte antiserum and the immune precipitates showed two components with apparent molecular weights of 72 000 and 27 000.

Animals↗
PubMed1978

Adhesive bonding of various materials to hard tooth tissues. X. Initial rates of adsorption of nickel or copper ions on hydroxyapatite surface.

Initial rates of ion-exchange adsorption of nickelous or cupric ions with calcium ions on the surface of synthetic hydroxyapatite were studied in aqueous nitrate solutions. A kinetic interpretation has been proposed. The determination of the initial rates is important for a systematic investigation of adhesion of certain properly designed substances that may mediate a chemical bonding between dental resins and "mordanted" calcified tissues.

Adhesives↗