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Biomedical subjects

J Hilgers

Publications and source records attributed to J Hilgers.

At least 109 records · Page 6Linked to original sources
PubMed1986

Iodination of monoclonal antibodies for diagnosis and radiotherapy using a convenient one vial method.

We have developed a convenient system that can be used to iodinate monoclonal antibodies for diagnosis or therapy. A vial, previously coated with 1,3,4,6-tetrachloro-3a, 6a-diphenyl glycouril (iodogen), is used as a reaction vessel. Iodination and separation of bound and free iodide, using AG1-X8 ion exchange resin, are both accomplished in this vial. We found 90 +/- 4% of the iodide which was added was incorporated, respectively, into each of four different monoclonal antibodies evaluated. Approximately 90% of labeled antibody was recovered in each case. The monoclonal antibody OC125 was labeled to specific activities up to 25 mCi/mg. Immunoreactivities of 82 +/- 2% using 125I and 66 +/- 5% using 131I were achieved. As the radioiodination is done in one sealed vial and takes less than 15 min, this procedure is safe and can be performed in any nuclear medicine laboratory. The final product, which is sterile and apyrogenic, is suitable for diagnostic and radiotherapeutic applications.

Antibodies, Monoclonal↗
PubMed1985

Novel antigenic specificity involving the blood group antigen, Lea, in combination with onco-developmental antigen, SSEA-1, recognized by two monoclonal antibodies to human milk-fat globule membranes.

Two monoclonal antibodies to human milk-fat globule membranes, which recognize an epithelial antigen designated MAM-3c, were found to bind strongly to epithelial glycoproteins derived from non-secretors. Further investigations, using purified glycoproteins and structurally defined oligosaccharides, established that the optimal antigenic structure for both antibodies involves the Type 1 based blood group antigen, Lea, in combination with the Type 2 based onco-developmental antigen, SSEA-1, (Formula: see text) as in lacto-N-difucohexaose II. The antibodies may also react with the corresponding monofucosyl structures lacking the 3- or 4- linked fucose residues and to a lesser extent with the afucosyl tetrasaccharide sequence as in lacto-N-tetraose. The Lea and SSEA-1 antigens are known to occur on human epithelial glycoproteins. However, this is the first report of an antigenic specificity involving a combination of the Type 1 and Type 2 based fuco-oligosaccharides and occurring on epithelial glycoproteins.

Antibodies, Monoclonal↗
PubMed1985

A polymorphic repetitive-sequence PR1 family. Evidence for meiotic instability.

When EcoRI digests of mouse genomic DNA were subjected to Southern blot analysis with the polymorphic repetitive sequence PR1 as a probe, one satellite-like band of 3.5 X 10(3) base-pairs, designated as PR1 family B, was detected in BALB/c-strain mice, but not in the DDD/1- or MOA-strain mice. Analysis of recombinant phage clones revealed that the repeating unit of the PR1 family B was 13.5 X 10(3) base-pairs long. This family consisted of a tandem array of repeating units and occupied as much as 2% of one BALB/c chromosome. Since the BALB/c-specific PR1 family B is not present in DDD/1 or MOA mice, the unpaired portion of the BALB/c chromosome may be looped out in a synaptonemal complex during meiosis in F1 hybrids of the BALB/c strain with DDD/1 or MOA. To determine the fate of this extra DNA, we examined the genotypes of the F1 hybrid mice and of the segregating populations. Although the PR1 patterns of F1 and most N2 mice are consistent with typical Mendelian inheritance, some N2 progeny showed an abnormal 3.5 X 10(3) base-pair band of unexpectedly reduced intensity. This indicated that the extra DNA of PR1 family B occasionally underwent recombination during meiosis in F1 mice, resulting in its apparent excision. Examination of PstI digests supported this interpretation.

Animals↗
PubMed1985

Characterization and chromosomal distribution of endogenous mouse mammary tumor viruses of European mouse strains STS/A and GR/A.

The endogenous mouse mammary tumor virus (MMTV) proviral copies in two genetically dissimilar mouse strains, STS/A, a European mouse strain, and BALB/c, were characterized. STS/A carries the same four MMTV proviral copies as GR.Mtv-2-; these strains share also most of the isoenzyme markers and are therefore highly related. Cellular DNA of GR.Mtv-2- contains a partial MMTV provirus that is not present in STS/A. GR.Mtv-2- is derived from GR; they differ in the locus Mtv-2 that contains one MMTV provirus. Expression of this Mtv-2 endogenous MMTV provirus is directly linked to mammary tumorigenesis in GR. MMTV proviral loci were studied using restriction enzyme analysis and the Southern transfer procedure using liver DNAs from recombinant inbred strains between BALB/c and STS/A. All segregating MMTV-specific EcoRI fragments were identified to MMTV proviral loci and most of these were localized by studying the cosegregation of the Mtv units and known chromosomal markers. Since STS/A, GR.Mtv-2-, and GR are highly related, the five complete endogenous MMTV proviruses of GR were located on the following chromosomes: Mtv-2 on chromosome 18, Mtv-3 on 11, Mtv-19 on 1, Mtv-20 on 4, whereas Mtv-8 has tentatively been located on chromosome 18 by Callahan et al. (R. Callahan, D. Gallahan, and Ch. Kozak (1984), J. Virol. 49, 1005-1008). GR and GR.Mtv-2 furthermore contain two incomplete MMTV proviral elements, one of which is also present in STS/A.

Animals↗
PubMed1985

Localization of the gene for the vitamin B12 binding protein, transcobalamin II, near the centromere on mouse chromosome 11, linked with the hemoglobin alpha-chain locus.

Somatic cell hybrids, recombinant inbred (RI) mouse strains, and backcross breeding experiments were used to locate the gene of transcobalamin II (Tcn-2), the vitamin B12 binding protein in mouse serum. TCN-2 was found to be useful genetic marker in the somatic cell hybrids. Selected hybrid clones were derived from fusions between GR mouse cells and the Chinese hamster cell line E36. Analysis of mouse specific chromosomal enzyme markers in relationship to TCN-2 secretion, in the hybrid clones, provided provisional evidence for assignment of the Tcn-2 locus to chromosome 11. The strain distribution pattern of the TCN-2 variants S and F in the RI series CXS, constructed from the cross of BALB/cHeA (TCN-2S) with STS/A (TCN-2F), implied a close linkage with the hemoglobin alpha-chain locus (Hba) on chromosome 11. Backcross breeding using inbred strains confirmed these findings and located the Tcn-2 gene closest to the centromere, linked with waved 2 (wa-2) and Hba with recombination frequencies of 6.9 and 19.2% each. The linkage group Tcn-2/wa-2/Hba was established.

Animals↗
PubMed1985

Expression of MAM-3 and MAM-6 antigens in endometrial and endocervical adenocarcinomas.

Expression of milkfat globule membrane antigens (MAM-3, MAM-6) was investigated by an indirect immunoperoxidase method on normal and malignant glands of the endocervical and endometrial tissues. MAM-3 antigens, as detectable with monoclonals 67D11 and 115G3, were not detected in normal endometrial glands, but they were found in the majority of endometrial adenocarcinomas. In the endocervix, MAM-3 antigens were present in almost all of the normal glands and in the cancerous glands. MAM-6 antigens, as detectable with monoclonals 115D8 and 115F5, were observed in majority of normal and neoplastic glands within the endometrium and endocervix. The staining appearance of the antigens was generally heterogenous in the neoplastic tissues but more homogenous in normal glandular tissues. These results are discussed and compared with the grade of histological differentiation, mucin production and positivity for CEA.

Adenocarcinoma↗
PubMed1985

Epithelial markers for paraffin-embedded human tissues. Immunohistochemistry with monoclonal antibodies against milk fat globule antigens.

About 200 human tumours and corresponding normal tissue samples were investigated by immunoperoxidase tests for the expression of MAM-3, MAM-5 and MAM-6 antigens, which had previously been defined by monoclonal antibodies to human milk fat globule membranes. All tissue specimens had been treated for routine histopathology, i.e. fixed in formalin and embedded in paraffin. One of the antigens, MAM-6, appeared to be an important epithelial marker, present in all normal and neoplastic breast tissue samples, in about 80% of non-mammary normal tissues and in more than 90% of non-mammary epithelial tumours. It could never be detected in normal and neoplastic mesenchymal and neuroectodermal structures. Direct comparison with the distribution of Carcinoembryonic Antigen (CEA), Tissue Polypeptide Antigen (TPA) and keratin provided clear evidence that MAM-6 is different from these well known epithelial markers. MAM-3 proved to be an additional important marker exhibiting a characteristic distribution pattern in those epithelial tissues investigated. In contrast to MAM-6, it could never be detected in renal cell cancers and carcinomas of the prostate gland, thus allowing differential diagnosis on the basis of immunohistochemistry. MAM-5, known to be associated with lactoferrin, was mainly detectable in secretory organs and their tumours. In the group of breast tumours, its expression was mainly seen in lobular cancers. These findings suggest a use for these new markers for routine histopathology.

Adenocarcinoma↗
PubMed1985

Characterization of epithelial cell islets in primary monolayer cultures of human breast carcinomas by the tetrazolium reaction for glucose 6-phosphate dehydrogenase.

Epithelial cell islets in primary monolayer cultures of human breast biopsies were characterized by combined immuno-, enzyme- and DNA cytochemistry as well as by analysis of attachment-, spread- and growth patterns. For cultivation we used explants from reduction mammoplasties, benign lesions, primary carcinomas and metastases. Milk fat globule membrane antigen (MFGM-A) was detected with a monoclonal antibody, and the tetrazolium reaction for glucose 6-phosphate dehydrogenase (G6PDH) as well as DNA content of the cultured cells were quantified. Spreading and growth of individual islets were studied by image analysis. Fibroblast-like cells did not express MFGM-A, and whereas epithelial (MFGM-A positive) cell islets of normal and benign origin showed cells with no or low G6PDH reaction, respectively, the majority of epithelial cell islets from 11 out of 21 carcinomas showed strong reaction. Cell islets with strong G6PDH reaction were sometimes hyperdiploid. Moreover, whereas cell islets with no or low reaction from both benign lesions and carcinomas readily attached and spread in a serum-free medium and showed population doubling times of 30 to 110 h, cell islets with strong reaction from carcinomas and metastatic lesions required serum for attachment and their growth rate was too low to be determined.

Antigens, Surface↗
PubMed1985

Translocations involving chromosome 1 in hormone-independent GR mouse mammary tumors.

Large marker chromosomes were found in 2 hormone-independent (HI) GR mouse mammary tumors, i.e. a tumor (TSl 75) that was already HI at the first transplantation, and a tumor (TSl 66) that became HI at the 19th passage. These marker chromosomes appear to be translocations to distal and proximal ends of chromosome 1, respectively. The translocation in tumor TSl 66 may be t(15:1).

Animals↗
PubMed1985

Horizontal transmission of the mouse mammary tumor virus in cage mates of the same and opposite sex of low and high mammary cancer strain mice.

Horizontal transmission of mouse mammary tumor virus (MTV) was investigated in cage mates of the same and opposite sex of low (BALB/c) and high mammary cancer strains (DD/Tbr, SHN and GR). By MTVp27 and MTVgp52 radioimmunoassay, MTV antigen expression was found in the salivary glands, mammary glands and secondary male genital organs of the MTV-free BALB/c strain. Infectivity and oncogenicity were also found in DDf or BALB/c mice by inoculating extracts of salivary gland and/or seminal vesicle in high mammary cancer strains. It is suggested that the primary source of the infectious agent in cases of caged animals of the same sex is saliva, while the primary source in cases of caged animals of the opposite sex is the seminal fluid, although additional infection through saliva cannot be ruled out in the latter case.

Animals↗