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J L Ware

Publications and source records attributed to J L Ware.

At least 55 records · Page 3Linked to original sources

The Malmö polymorphism of coagulation factor IX, an immunologic polymorphism due to dimorphism of residue 148 that is in linkage disequilibrium with two other F.IX polymorphisms.

A mouse monoclonal antibody (MAB 9.9) to coagulation factor IX (F.IX) detects a polymorphism in the plasma of normal people. Its epitope has been narrowed down to less than 6 amino acids in the activation peptide of the X-linked F.IX protein. The activation peptide contains a dimorphism--Thr:Ala--at position 148 of the protein. Using synthetic oligonucleotides, we have demonstrated that (1) the F.IX which reacts with 9.9 has Thr at position 148 and (2) that which does not has Ala. Positive reactors (148thr) are designated Malmö A, and negative reactors (148ala) are designated Malmö B. The plasma levels of AA women are indistinguishable from those of A men, and both B men and BB women are null against MAB 9.9. The plasma level of Malmö A in AB women is approximately half that of AA women, and "lyonization" is clearly operating in the heterozygotes. The dimorphism is in strong linkage disequilibrium with two other intragenic RFLPs, TaqI and XmnI. Furthermore, intragenic crossing-over--including double crossing-over--appears to have occurred between the three sites. Seven of the eight possible haplotypes have been identified, five in men and two others in women. The immunoassay that identifies approximately 50% of the AB women in the pool of Malmö A females with 95% confidence identifies men unambiguously as A or B. The assay would be very useful for population-genetic studies of the Malmö epitope if the studies were limited to men.

Antibodies, Monoclonal↗

The ribosomal DNA transcription unit of the house cricket, Acheta domesticus.

A composite map representing a single ribosomal DNA repeat unit of the house cricket, Acheta domesticus, was constructed from overlapping cloned fragments. Sites in the repeat unit for nine restriction enzymes were mapped. R-loop mapping of sequences coding for 18 S and 28 S RNA demonstrates that the 58-kb ribosomal DNA repeat unit contains a novel-sized internal transcribed spacer of 8.4 kb. The existence of this large spacer was confirmed in genomic DNA, most if not all of the genomic repeat units containing such a spacer. A 15- to 17-kb ribosomal RNA precursor transcript is synthesized as predicted on the basis of the size of the internal transcribed spacer. The 5.8 S RNA gene is localized to a 1-kb sequence immediately 5' to the 28 S gene. The coding regions examined contain no intervening sequences analogous to those described within ribosomal DNA of other eukaryotes. Only 11% of the repeat unit codes for mature ribosomal RNA, while the remainder is nontranscribed (71%) and transcribed (18%) spacer DNA.

Animals↗

Factor IXAlabama: a point mutation in a clotting protein results in hemophilia B.

Factor IXAlabama is a variant factor IX molecule responsible for a clinically moderate form of hemophilia B. Twenty-five kilobases (kb) of the variant gene, including seven exons coding for the structural protein, were cloned and characterized. The restriction map and the arrangement of coding regions are identical to those of the normal gene. DNA sequence analysis of the coding regions revealed a single base-pair difference between the gene for factor IXAlabama and the normal factor IX gene. An adenine to guanine transition in the first nucleotide of exon d causes the substitution of a glycine codon (GGT) for the normal aspartic acid codon (GAT). This point mutation results in a single amino acid substitution at residue 47 of the zymogen and represents the genetic defect in factor IXAlabama.

Amino Acid Sequence↗

Metastatic phenotype of human prostate tumor cells in athymic nude mice: alteration by exposure to ethyl methanesulfonate and "reversion" by 5-azacytidine.

The human prostate tumor subline 1-LN-PC-3-1A (1-LN) is reproducibly metastatic in adult athymic nude mice. Cells surviving a brief in vitro exposure to ethyl methanesulfonate (EMS) exhibited a profound decrease in capacity for experimental lung metastasis in nude mice. Thirty days after EMS treatment, 1 X 10(6) uncloned EMS-treated 1-LN cells (1-LN-EMS-10) were injected IV into groups of 6 to 8-week-old male athymic nude mice (BALB/cAnBOM). A median of 8.5 colonies/lung was observed among 20 1-LN-EMS-10-injected mice, which was significantly different from the median of 51 colonies/lung produced among 14 1-LN-injected mice (P = 0.0002). This altered phenotype remained stable during 150 days of continuous culture. However, the 1-LN-EMS-10 cells were tumorigenic in 10/10 nude mice injected SC. Single lung tumor colonies recovered from 1-LN-EMS-10-injected mice and reinjected IV into nude mice produced medians of 32-63 colonies/lung. The altered metastatic phenotype resulting from treatment of 1-LN with EMS was reversed by exposure to a noncytotoxic dose of 5-azacytidine, but unaffected by a second exposure to EMS. Collectively these data demonstrate that the metastatic phenotype of these human tumor cells in athymic nude mice can be heritably altered by in vitro exposure to EMS and 5-azacytidine. Analysis of the mechanisms underlying these phenotypic changes may provide insight into parts of the complex process of tumor cell evolution.

Animals↗

In vitro synergism between hybrid immunotoxins and chemotherapeutic drugs: relevance to immunotherapy of prostate carcinoma.

Cultured prostate carcinoma cells incubated in the presence of a novel hybrid immunotoxin and ricin A chain exhibited synergy with the chemotherapeutic drugs vinblastine, methotrexate, and bleomycin. No cooperative effect was noted with adriamycin. Under conditions where individual components of immunotoxin or chemotherapeutic drug mixtures were nontoxic or minimally toxic the immunotoxin-drug mixture exhibited marked impact on 14C amino acid incorporation into prostate carcinoma cells. Analysis of drug-treated cells by flow cytometry indicated that cells exposed to vinblastine and bleomycin bound hybrid immunotoxin antibody to a greater extent than cells not exposed to these drugs. Adriamycin did not exhibit synergistic cytotoxicity with hybrid immunotoxin. Also, adriamycin did not enhance antibody binding as evaluated by flow cytometry. The fact that hybrid monoclonal antibody-ricin A chain (HIT-RAC) conjugates inhibited uptake of 14C amino acids 3 to 10-fold within 48 h of incubation with target cells and that this inhibition was further increased 2 to 3-fold in conjunction with three out of four chemotherapeutic drugs tested may be attributed to the unique cytotoxicity imposed by the hybrid immunotoxins. The RAC moiety is not chemically coupled to antibody but instead occupies one of the antigen-combining sites of the molecule. In this manner, RAC is closely juxtaposed to the cell membrane of the target cell and is anchored in this position via binding of the remaining antigen-combining site to p40 prostate restricted antigen.

Antibodies, Monoclonal↗

Factors influencing phenotypic diversity of human prostate carcinoma cells metastasizing in athymic nude mice.

Three related human prostate carcinoma cell lines, PC-3, 1-LN-PC-3-1A (1-LN), and 1-LN-PC-3-1A clone 4 (clone 4) were compared in terms of relative metastatic capacity in adult and young male nude mice. Only 1-LN produced lung metastases after intravenous injection into both 6- to 8-week-old and 4-week-old nude mice, as well as in mice injected intraperitoneally. The extent of the phenotypic diversity exhibited by these human prostate tumor lines was influenced by inherent dissemination ability, age of the host, and route of injection. These lines provide a useful system for the analysis of the biology of human tumor metastasis in nude mice.

Animals↗

Evidence for a novel hybrid immunotoxin recognizing ricin A-chain by one antigen-combining site and a prostate-restricted antigen by the remaining antigen-combining site: potential for immunotherapy.

We have used cell fusion technology to produce second-generation hybridomas which secrete a population of murine monoclonal antibodies (MABs), a portion of which are bifunctional antibodies. The bifunctional hybrid MABs produced are capable of recognizing ricin A-chain (RAC) via one antigen-combining site and a prostate-restricted antigen via the other antigen-combining site of the IgG molecule. The second-generation hybridoma described in this report resulted from the fusion of spleen cells from mice immunized with purified RAC to hybridoma cells which secrete prostate-directed alpha Pro 15 monoclonal antibody. We have demonstrated that the MAB population secreted by the second-generation hybridoma can be physicochemically separated into distinct populations exhibiting differential binding to the cultured prostatic carcinoma cell surface and to RAC immobilized in a solid phase; specifically, a subset of the monoclonal antibody population which exhibits high binding to both prostatic carcinoma cells and to solid-phase RAC can be enriched by physicochemical methods. Binding of hybrid immunotoxin (HIT) MAB population to RAC can be quantitatively reduced by prior adsorption of the antibody population with prostate carcinoma cells; conversely, hybrid MAB binding to prostate carcinoma cells can be quantitatively reduced by prior adsorption with RAC. The biologic impact of the HIT has been evaluated by the ability of the HIT-RAC conjugate to reduce the uptake of 14C-amino acids into cellular protein. This effect is selective, since HIT-RAC conjugates do not exert an effect on labeled amino acid uptake by a cell line that does not express the target antigen recognized by the prostate-directed component of the hybrid MAB. Furthermore, depression of labeled amino acid uptake by prostate carcinoma cells exhibits a stoichiometric relationship with respect to both the concentration of HIT-MAB and to RAC to which the cells are exposed. The biologic impact of HIT-RAC conjugates on prostate carcinoma cells is enhanced markedly in the presence of lysosomotropic amines.

Adsorption↗

1,10-Phenanthroline reversibility inhibits proliferation of two human prostate carcinoma cell lines (PC-3 and DU145).

The metal chelator 1,10-phenanthroline reversibly inhibits proliferation of two human prostate carcinoma cell lines, PC-3 and DU145. Inhibition is dose-dependent, and persists for several days after removal of the chelator. The ability to induce reversible quiescence in human prostate carcinoma cells in vitro may facilitate the study of their growth cycle biochemistry.

Antigens, Surface↗

Characterization of prostate-tissue-directed monoclonal antibody, alpha-Pro 13.

The alpha-Pro 13-secreting hybridoma was produced by immunizing mice with an equal mixture of PC-3, DU145, and LNCaP established prostatic carcinoma cell lines. The specificity of alpha-Pro 13 monoclonal antibody was evaluated by the criteria of differential binding to cultured cells; differential binding to extracts of malignant prostate, nonmalignant prostate, and malignant and nonmalignant tissues of various histiotypes in solid phase radioimmunoassay; and by immunoperoxidase staining of primary surgical tissues of varied histiotypes. The data generated by multiple assay investigation indicate that alpha-Pro 13 exhibits preferential binding to the ductal epithelium of prostate tissue; immunoperoxidase evaluation indicates a considerable heterogeneity of staining of ductal epithelial cells. The most prevalent cross-reactivity of alpha-Pro 13 monoclonal antibody with non-prostate tissue occurs with blood vessel endothelium of restricted tissues. Electrophoretic analysis of immunoprecipitates from radioiodinated prostatic tumor extracts indicates that the molecule recognized by alpha-Pro 13 is of 120,000 dalton apparent nonreduced molecular weight. Under reducing conditions, the antigen (p40) consists of a major component of 40,000 dalton apparent MW and a minor component of 17,000 dalton MW. p40 has an isoelectric point of 3.5-4.5. The antigen is intrinsically stable on the PC-3 cell surface; its release into spent culture medium is negligible. p40 is also stable upon complexation with alpha-Pro 13 antibody in that it is not shed from the cell surface as an immune complex nor is it endocytosed to any extent as an immune complex.

Antibodies, Monoclonal↗

Monoclonal antibodies to different epitopes on a prostate tumor-associated antigen. Implications for immunotherapy.

Mouse monoclonal antibodies alpha Pro3 and alpha Pro5 bind to different epitopes on an antigen (p54) of 54 kD reduced and 175 kD nonreduced MW. p54 antigen has been characterized previously with regard to tissue distribution using alpha Pro3 monoclonal antibody; the p54 antigen is present in substantially greater quantities in malignant prostatic tissue extracts than in benign prostatic and nonmalignant nonurogenital tissue extracts. In this report, we have established that alpha Pro5 and alpha Pro3 monoclonal antibodies exhibit same molecule-different epitope recognition. That both antibodies recognize the same molecular entity has been established by partial physiochemical characterization of the antigen recognized by the two antibodies and by sequential immunoprecipitation experiments. Different determinant recognition was established by lack of competitive surface binding between alpha Pro3 and alpha Pro5 to a prostatic carcinoma cell line. The p54 antigen can be labeled with glucosamine and immunoprecipitated from urea-solubilized membrane proteins; however, p54 cannot be detected by immunoprecipitation in a glycosylated form in spent culture medium removed from glucosamine-labeled cells. Experiments using indirect cellular immunoassays and directly radioiodinated monoclonal antibody have shown that both alpha Pro3 and alpha Pro5 form stable complexes with p54 antigen on the prostatic carcinoma cell surface. To the extent that modulation occurs upon interaction of p54 with alpha Pro3 and alpha Pro5; endocytosis of the immune complex appears to be the primary route of modulation. Furthermore, modulation by endocytosis is more intense when alpha Pro3 and alpha Pro5 are used in combination than when either monoclonal antibody is used alone. Although in vivo biologic behavior does not invariably correlate with in vitro behavior, careful in vitro analysis of monoclonal antibodies with respect to cell surface behavior, nevertheless, should precede in vivo evaluation. The data presented in this report indicate that preliminary in vitro analyses will expedite the effectiveness of in vivo immunotherapeutic trials; preliminary in vitro evaluations are absolutely essential if monoclonal-toxic agent (e.g., ricin A) conjugates, which must be internalized by the tumor cell to achieve cytotoxicity, are employed as immunotherapeutic agents.

Adenocarcinoma↗

Spontaneous metastasis of cells of the human prostate carcinoma cell line PC-3 in athymic nude mice.

Spontaneous metastasis and extensive invasiveness were observed in athymic nude mice injected with human prostatic carcinoma cells of the PC-3 line or heterotransplants of nude mouse supported PC-3 tumor. In 3 experimental series, 60, 63 and 50 per cent of the nude mice receiving subcutaneous inoculations of PC-3 cells or tumor heterotransplants developed 1 or more lymphatic tumor metastases. Examination of metaphase-arrested cells recovered from the metastatic sites confirmed the tumor origin as human in each case. Cells recovered from 1 nude mouse supported subline, MPC-3-10, frequently exhibited double minute chromosomes in addition to the typical PC-3 chromosomal profile. These observations provide the foundation for a study of the relationship between prostate carcinoma cell characteristics and lymphatic metastasis in the nude mouse.

Animals↗

Production of monoclonal antibody alpha Pro3 recognizing a human prostatic carcinoma antigen.

The monoclonal antibody alpha Pro3 recognizes an antigen concentrated in human primary prostatic carcinoma tissue removed surgically. Although the antigen was detectable in extracts of human normal and malignant nonprostatic tissue, as well as in benign prostate tissue, quantitative absorption analysis revealed a substantially greater quantity of the antigen in malignant prostate tissue. The antigen recognized by alpha Pro3 in primary prostatic carcinoma has an apparent nonreduced molecular weight of 175,000 and an apparent subunit molecular weight of 54,000. This antigen, p54, appears to be present on the surface of cultured prostatic tumor cells of the PC-3 cell line, but its location in vivo has not been defined. Successful competition between alpha Pro3 and prostatic carcinoma patient serum immunoglobulin for a Mr 54,000 antigen (reduced molecular weight) present in prostatic carcinoma tissue extract suggests that p54 may play a significant role in the immunobiology of prostatic carcinoma. alpha Pro3 has potential as a sensitive probe for an antigen relevant to human tumor biology.

Animals↗

A serologic approach to the definition of human prostatic carcinoma antigens.

We have used an immunoaffinity system whereby immunoglobulin from patients with prostatic carcinoma was coupled to solid phase protein A; the immobilized IgG was subsequently exposed to radiolabeled antigen from autochthonous or allogeneic primary tumor extracts or to radiolabeled antigen from a nude mouse-supported prostatic carcinoma cell line. Material specifically bound by prostatic carcinoma patient immune IgG was quantitatively eluted from the immunoadsorbent and characterized with regard to molecular weight. Sequential adsorption analyses of patient sera with normal human tissue pools, normal prostatic tissue, prostatic carcinoma tissue, and tissue from other urogenital malignancies has allowed a definition of those antigenic specificities relevant in the immunobiology of prostatic carcinoma. The patient humoral response was observed to be directed primarily toward a complex array of antigens representing normal human tissue components; serorecognition of prostate tumor associated antigens was discernible from that of common tissue antigens only after rigorous adsorption analyses. Preliminary results indicate that the prostatic cancer patient humoral antibody response may be directed toward either altered histocompatibility complex antigens or toward antigens physically associated with histocompatibility complex antigens.

Antigen-Antibody Reactions↗

Keratoacanthoma.

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Adult↗