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R Cigén

Publications and source records attributed to R Cigén.

7 recordsLinked to original sources
PubMed1985

Structural difference between the two forms of guinea-pig beta 2-microglobulin and their occurrence in inbred guinea-pig strains.

The structural difference between two forms (basic and acidic) of guinea-pig beta 2-microglobulin (beta 2m) has been established. Both forms are present in urine from inbred guinea-pig strains. The beta 2m forms were each digested with carboxypeptidase Y and carboxypeptidase A contaminated with carboxypeptidase B. Released amino acids were separated from remaining protein, dansylated and analysed by 2-dimensional TLC on polyamide layer sheets. From the results it was concluded that the basic beta 2m form has lysine and the acidic beta 2m form has asparagine as their respective C-terminal amino acids. The acidic form is also 1 amino acid (lysine) shorter than the basic form, which is supported by electrophoretic studies on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The presence of the 2 forms of beta 2m in urine from inbred guinea-pig strains 2 and 13, shown by gel filtration and ion exchange chromatography, makes it unlikely that the 2 forms are a result of genetic polymorphism.

Amino Acid Sequence↗
PubMed1983

Distribution of the two forms of guinea-pig beta 2-microglobulin originally detected in urine.

Two distinct forms of beta 2-microglobulin (beta 2m) have been detected in pooled guinea-pig serum from outbred animals using ultrafiltration, gel filtration and ion exchange chromatography. These two forms probably correspond to the two beta 2m forms, with different electrophoretic mobility, that have been previously identified in guinea-pig urine. In solubilized membranes from perfused guinea-pig livers only the basic form of beta 2m could be found. These results may indicate that the two beta 2m forms should not be ascribed to genetic polymorphism but rather are a result of post-translational modification.

Animals↗
PubMed1981

Binding of beta 2-microglobulin by heterologous sera.

Purified human, rat or guinea-pig beta 2-microglobulin (beta 2m) was mixed with sera from guinea-pig, rat, mouse, rabbit, horse, goat, cow, rhesus monkey or man. The mixtures were incubated at 37 degrees C for various lengths of time. When the sera were separated by gel-chromatography on Sephadex G-200, beta 2m was traced not only in 'free' form but also in fractions with higher molecular weights. Evidence is presented suggesting that heterologous beta 2m binds to beta 2m-containing molecules in sera by exchange with the homologous counterpart.

Animals↗
PubMed1980

beta 2-Microglobulin.

In the sixties, Ingemar Berggård discovered, isolated and characterized the low molecular weight protein beta 2-microglobulin. The relations of beta 2-microglobulin to the immune system have led to intensive research on this protein. The present work reviews the purification and characterization of human beta 2-microglobulin and animal homologues, the association of beta 2-microglobulin to other molecules, the functional studies with beta 2-microglobulin and antibodies against beta 2-microglobulin, and the evolutionary studies on beta 2-microglobulin.

Animals↗
PubMed1979

Effects of anti-guinea-pig beta 2-microgloblin antibodies on lymphocyte transformation induced by specific antigens or mitogens.

The effects of a goat anti-guinea-pig beta 2-microglobulin antiserum (a beta 2m) on lymphocyte transformation, induced by specific antigens or mitogens, were studied. a beta 2m was found to exert inhibitory effects on antigen stimulation, with three different antigens (purified protein devivative, hen egg-white lysozyme, and ovalbumin), and on stimulation induced by the 'T-cell mitogens', concanavalin A and phytohaemagglutinin, and the 'mixed mitogen', pokeweed mitogen. Stimulation induced by the 'B-cell mitogens', dextran sulphate and bacterial lipopolysaccharide, did not seem to be inhibited to the same extent by a beta 2m. The inhibitory effects seemed specific, as they were not seen with a beta 2m that had been absorbed on a column with insolubilized purified guinea-pig beta 2m nor with normal goat serum. Time studies indicated that the inhibitions started already during the first day of culture.

Animals↗
PubMed1977

Relationships between beta2-microglobulin and alloantigens coded for by the major histocompatibility complexes of the rabbit and the guinea pig.

Treatment of rabbit and guinea pig lymphocytes with Fab' fragments of anti-beta2-microglobulin completely inhibited the cytotoxic effects of alloantisera to RLA or GPLA antigens, respectively. Aggregation of beta2-microglobulin on the lymphocyte surface by successive incubations with goat anti-beta2-microglobulin on the lymphocyte surface by successive incubations with goat anti-beta2-microglobulin and F(ab')2 fragments of rabbit anti-goat IgG also made rabbit lymphocytes resistant to lysis by anti-RLA, and guinea pig lymphocytes resistant to lysis by anti-RLA, and guinea pig lymphocytes resistant to lysis by anti-GPLA. The two kinds of pretreatment of guinea pig lymphocytes did not affect the cytotoxicity of antisera directed against guinea pig Ia antigens. These results in conjunction with previous findings in the mouse and in man suggest that beta2-microglobulin on the lymphocyte surface in mammals is generally associated with major serologically defined histocompatibility antigens but not with I-region-associated antigens.

Animals↗