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D Solter

Publications and source records attributed to D Solter.

At least 73 records · Page 4Linked to original sources

Monoclonal antibody to murine embryos defines a stage-specific embryonic antigen expressed on mouse embryos and human teratocarcinoma cells.

A murine stage-specific embryonic antigen (SSEA3) is defined by reactivity with a monoclonal antibody prepared by immunization of a rat with 4- to 8-cell-stage mouse embryos. This antigenic determinant, present on oocytes, becomes restricted first to the inner cell mass at the blastocyst stage, and later to the primitive endoderm. Murine teratocarcinoma stem cells do not react with this antibody, whereas human teratocarcinoma stem cells are SSEA3-positive. This antigenic determinant is not expressed on a variety of other human and murine cell lines, but is found on the surface of human erythrocytes. It is a carbohydrate and is present on both cell-surface glycolipids and glycopeptides. These results demonstrate the feasibility of identifying stage-specific antigenic determinants with monoclonal antibody prepared against embryos. The need for thorough screening on a variety of cell types to establish developmentally important cross-reactivities is also emphasized.

Animals

Immunohistochemical localization of murine stage-specific embryonic antigens in human testicular germ cell tumors.

Monoclonal antibodies raised against and/or recognizing stage-specific antigens on preimplantation mouse embryos and stem cells of murine teratocarcinoma were used to localize these antigens immunohistochemically on human testicular germ cell tumors. SSEA-1, the antigen found on mouse embryonal carcinoma (EC) cells and embryonic cells from the 8-cell stage embryo onward, including the fetal primordial germ cells, was detected on yolk sac carcinoma components of human tumors, but not on EC cells. SSEA-3, the antigen found on follicular ova, fertilized eggs, early cleavage stage embryonic cells, and visceral endodermal cells of the mouse embryo, but not on mouse EC cells, was detected on human EC cells. Both antigens were found on the cell surface of fetal testicular germ cells but not in the seminiferous tubules of adult human testes. These data point out differences between human and murine EC cells suggesting that human EC cells correspond developmentally to a less mature embryonic cell than the murine EC cells. The possible histogenesis of human germ cell tumors from primordial and/or fetal germ cells is briefly discussed.

Animals

Embryo-derived teratocarcinoma. III. Development of tumors from teratocarcinoma-permissive and non-permissive strain embryos transplanted to F1 hybrids.

Seven-day-old mouse embryos of two teratocarcinoma-permissive (C3H and BALB/c) and two teratocarcinoma-non-permissive (C57BL/6 and AKR) strains were transplanted to their F1 hybrids to determine the role of the genetic background of the recipient animals in controlling embryo-derived teratocarcinogenesis. The yield of teratocarcinomas in F1 hybrid recipients of embryonic grafts was either identical with the yield in syngeneic recipients or increased or decreased, depending on the strain of the embryo and the F1 hybrid combination. In certain hybrids, the yield of malignant tumors remained the same as in the syngeneic recipients but the F1 hybrids exerted a stimulatory effect on tumor growth and the tumors weighed more than those in syngeneic recipients. A matroclinous effect was also seen in certain hybrids. These data indicate that embryo-derived teratocarcinogenesis in histocompatible F1 mice depends on the genetic background of adult recipients. The teratocarcinogenic potential of non-permissive and permissive strain mouse embryos can be modified by choosing appropriate F1 hybrids for embryonic transplantations.

Animals

A murine stage-specific embryonic antigen (SSEA-2) is expressed on some murine SV40-transformed cells.

A stage-specific embryonic antigen-2 (SSEA-2) found on murine preimplantation embryos is maximally expressed on 4- to 8-cell stage embryos and is present in decreasing amounts of morulae and blastocysts. This antigenic determinant is also expressed on murine teratocarcinoma cells, sperm, and some, but not all, SV40-transformed mouse cell lines. Analysis of solubilized immunoprecipitates by SDS-gel electrophoresis indicates that this cell surface molecule is not the 54,000 m.w. protein shared by teratocarcinoma and SV40-transformed cell lines.

Absorption

Expression of H-2, laminin and SV40 T and TASA on differentiation of transformed murine teratocarcinoma cells.

Murine embryonal carcinoma cells (ECCs) do not express antigens of the major histocompatibility complex (H-2), but do express cell-surface molecules shared with early embryos. ECCs are also characterized by their insusceptibility to infection by various oncogenic viruses, and their ability to differentiate into a variety of adult cell types. Differentiation of ECCs in vitro can occur spontaneously or can be induced. On exposure to retinoic acid the ECC line F9 (ref. 13) differentiates into cells which have the characteristics of parietal endoderm. When ECCs are exposed to simian virus 40 (SV40), the SV40 tumour (T) antigen is not expressed, although the virus genome reaches the nucleus, and a primary transcript of the SV40 A gene is made. However, following exposure to retinoic acid, the differentiated cells, like most mouse somatic cells, are susceptible to SV40 abortive infection and synthesize large T and small t antigens. To monitor the molecular events associated with the expression of the SV40 A gene on differentiation, we have constructed an ECC line (F9 12-1) containing a single integrated copy of the SV40 genome. This was accomplished by introducing a recombinant plasmid consisting of pBR322 linked to the herpes simplex type 1 thymidine kinase gene and SV40 genome into a thymidine kinase-deficient F9 cell line. We report here that in F9 12-1 cells exposed to retinoic acid, synthesis of the SV40 A gene product(s), T and tumour-associated specific antigens (TASA), parallels the appearance of the normal hallmarks of differentiation in this cell line, H-2 antigens and the basement membrane protein laminin.

Animals

Independent regulation of H-2K and H-2D gene expression in murine teratocarcinoma somatic cell hybrids.

Cells of two teratocarcinoma stem cell lines (PCC4 azaguanine [aza] 1 and F9 5-bromodeoxyuridine [BrdU]) were fused with normal mouse spleen cells and mouse thymoma-derived cells (BW 5147), respectively. Hybrid clones were tested for the expression of molecules coded by the H-2K and -2D genes both by absorption analysis of conventional H-2 sera and by indirect antibody-binding radioimmunoassay with monoclonal antibodies. Somatic cell hybrids between PCC4 aza 1 and spleen cells morphologically resemble teratocarcinoma stem cells and do not express H-2 antigens. However, after differentiation in vitro, one of these hybrid clones expresses the H-2K and -2D gene products of both parental cell lines, one close expresses H-2-D- but not H-2K-coded antigenic determinants, and one clone remains H-2 negative. Somatic cell hybrids between F9 BrdU and BW 5147 resemble fibroblasts. Analysis of a series of hybrid clones revealed some clones that express both the H-2K- and H-2D-coded antigenic specificities of both parental alleles, some that express H-2D gene products strongly and the H-2K gene products very weakly, and some that express H-2D- but not H-2K-coded molecules. These results imply independent regulation of expression of the H-2K and -2D genes. The H-2D gene products appear to be preferentially expressed if the hybrid cells are capable of expressing H-2. The results suggest complex regulatory mechanisms that are H-2K and H-2D specific.

Animals

Embryo-derived teratocarcinoma. II. Teratocarcinogenesis depends on the type of embryonic graft.

Early post-implantation mouse embryos or their embryonic and extraembryonic portions were transplanted under the kidney capsule of adult isogenic recipients in order to test the tumor-producing potential of various grafts and to establish the optimal conditions for teratocarcinoma production. The highest yield of malignant tumors was obtained from 7-day embryos transplanted in toto. Severing the extraembryonic portion of 7-day egg cylinders prior to transplantation of the embryonic part reduced the number of teratocarcinomas to values comparable with those obtained from transplanted 6-day embryos. The extraembryonic portion of 7-day embryos produced no tumors. These data suggest that extraembryonic portions of the 7-day egg cylinder do not have tumorigenic potential alone, but may increase the yield of teratocarcinomas from the embryonic portion of the egg cylinder.

Animals

Localization of I-131-labeled tumor-specific monoclonal antibody in the tumor-bearing BALB/c mouse.

One of the most frequent indications for patient imaging is the need to establish the presence or absence of malignant disease. Considerable effort has been invested in attempting to develop tumor-specific radiopharmaceuticals. We report the localization of an iodine-131-labeled, hybridoma-derived monoclonal antibody in the MH-15 teratocarcinoma-bearing BALB/c mouse. Tumor-to-muscle and tumor-to-blood ratios of 150:1 and 15:1, respectively, were observed at 5 days after administration of 15 microCi of labeled antibody. The relationship between the optimal imaging time and localization kinetics is discussed.

Animals