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S Kvist

Publications and source records attributed to S Kvist.

45 records · Page 3Linked to original sources
PubMed1979

Radioimmunoassay determinations of murine beta 2-microglobulin and an H-2 antigen-like serum component.

Normal mouse serum contains H-2 antigen-like components. One such protein consists of a 40 000 dalton chain and beta 2-microglobulin (beta 2m) and the other component contains the two H-2 antigen-like subunits and, in addition, two larger polypeptide chains with apparent molecular weights (mol. wt.) of 65 000 and 80 000. Radioimmunoassay procedures specific for the H-2 antigen-like chain and beta 2m, respectively, have been developed. Whereas free beta 2m and beta 2m associated with other polypeptide chains reacted identically in the beta 2m radioimmunoassay, the two serum forms of the H-2 antigen-like chain displayed different reactivities in the heavy-chain assay. The low mol. wt. protein complex, comprising the 40 000 dalton chain and beta 2m, inhibited in the heavy-chain assay identically with the standard. However, the high mol. wt. complex containing the H-2 antigen-like chain gave rise to a biphasic inhibition profile. This was apparently due to some antigenic determinants of the 40 000 dalton chain being buried by the 65 000 and 80 000 dalton chains. Inhibition curves parallel with the standard were, however, obtained on dissociation of the high mol. wt. protein complex with sodium dodecyl sulfate. Thus, by subjecting serum to the ionic detergent-sensitive radioimmunoassay, procedures for the two H-2 antigen-like chains could be developed. The serum levels of the H-2 antigen-like chain and of beta 2m vary with the age of the animal, and adult levels are recorded only at 6 to 7 weeks of age. The serum concentrations of the two proteins are strongly correlated. The H-2 haplotype appears to partly regulate the serum levels of the two proteins. Mice of the H-2f haplotype contain about 40-fold lower levels of the H-2 antigen-like chain than do mice of other strains.

Age Factors↗
PubMed1979

Non-H-2 antigens on fibroblasts and an embryocarcinoma cell line react with xenoantisera against H-2 antigens.

The murine embryocarcinoma cell line F9 lacks the classical transplantation antigens. However, rabbit anti-H-2 antigen sera, recognizing "backbone structures" of H-2 K and D antigens, react with three types of molecules manufactured by F9 cells. A 49,000- and a 25,000-dalton chain are glycoproteins located on the cell surface. The third component with an apparent molecular weight of 15,000, and the 25,000-dalton chain seem to be unrelated to the 49,000-dalton glycoprotein. The 25,000- and 15,000-dalton components are not manufactured by splenocytes, thymocytes, hepatocytes, or various lymphoma, mastocytoma, and plasmacytoma cell lines. However, fibroblasts derived from both embryos and adult animals synthesize 25,000- and 15,000-dalton molecules reactive with the rabbit anti-H-2 antigen sera. The 49,000-, 25,000-, and 15,000-dalton molecules are not recognized by a syngeneic anti-F9 cell serum.

Animals↗
PubMed1978

Molecular association between transplantation antigens and cell surface antigen in adenovirus-transformed cell line.

A rat cell line (A2T2C4) transformed with adenovirus type 2 elicited cytotoxic T lymphocytes in syngeneic rats. Cytotoxicity was abolished by a rabbit antiserum directed against the major histocompatibility (AgB) antigens and by a syngeneic rat antiserum raised against the virus-transformed cell line. The syngeneic antiserum immunoprecipitated surface proteins with apparent molecular weights of 45,000, 19,000, 17,000, and 12,000 from the A2T2C4 cells but it displayed no reactivity against primary rat fibroblasts and spleen cells. The rabbit antiserum against AgB antigens precipitated a 19,000-dalton component from the A2T2C4 cells which was not observed in primary rat fibroblasts. Sequential immunoprecipitation revealed identity between the major polypeptides recognized by the two antisera. Because the rabbit anti-AgB antigen serum was specific for the transplantation antigen subunits and because the syngeneic rat antiserum against the A2T2C4 cells failed to react with the AgB antigens in normal cells, it is concluded that the 19,000-dalton component is coprecipitated with the AgB antigens. Antisera directed specifically against beta2-microglobulin and the alloantigenic AgB antigen subunit also coprecipitated the 19,000-dalton component. These results indicate that the AgB antigen subunits form a ternary complex with a virus-coded protein on the surface of the virus-transformed A2T2C4 cells. This molecular complex may be recognized by the cytoloytic T lymphocytes

Adenoviruses, Human↗
PubMed1978

Reactions and crossreactions of a rabbit anti-H2 antigen serum.

A rabbit antiserum raised against highly purified, papain-solubilized H-2d antigens contained two sets of non-crossreacting antibodies directed against each one of the two H-2 antigen subunits. The antiserum recognized only 12,000 and 47,000 dalton polypeptide chains when splenocyte membrane glycoproteins were analysed. Among the molecules precipitated with the rabbit antiserum all H-2K and D antigens were present. In addition to regular H-2K and D antigens minor amounts of material with the typical H-2 antigen subnit structure, but lacking alloantigenic determinants, were precipitated by the antiserum. These 'non-H-2 antigens' were produced in relatively greater amounts by T-cells than by B-cells. Both sets of antibodies in the rabbit antiserum reacted with the TL antigens demonstrating that there is an immunological crossreactivity between the classical alloantigenic H-2 antigen chain and the alloantigenic TL antigen chain. The F9 cell line, believed to represent cells at the morula stage, display H-2 antigen-like structures as revealed by the rabbit antiserum.

Animals↗
PubMed1978

Identification of H-2 and Ia-antigen analogues in several species by immunological crossreactions of xenoantisera.

Rabbit antisera against H-2K and D antigens react with molecules composed of 12,000 and 45,000 dalton subunits derived from human, monkey, rat, guinea-pig, cow and pig lymphocytes. The antisera failed, however, to react with similar type molecules from chicken. A rabbit antihuman beta 2-microglobulin serum reacted with chicken molecules comprising 12,000 and 45,000 dalton polypeptide chains. An antiserum against HLA-DR antigens reacted with Ia-antigen-like molecules from monkey, rat, mouse, guinea-pig, cow, pig and chicken lymphocytes. All Ia-antigen-like molecules displayed two dissimilar subunits. The present data suggest that xenoantisera directed against highly purified MHC antigens from one species may be useful tools in elucidating the structure of similar antigens in other species where alloantisera are not available.

Animals↗
PubMed1978

Cell surface antigens containing beta2-microglobulin as the common subunit.

beta2-Microglobulin, which was first discovered in various biological fluids, has been shown to be the common subunit of the human HLA-A,B,C antigens. In the mouse beta2-microglobulin is associated with H-2K, D and L antigens and with TL and Qa-2 antigens, beta2-microglobulin and the heavy HLA antigen chains are similar in structure to the immunoglobulins and it is suggested that the two types of molecules have had an interrelated evolution. Data are also presented which suggest that the structural similarity between transplantation antigens and immunoglobulins may be paralleled by a functional similarity as well.

Animals↗