Biomedical subjects

J Lubinski

Publications and source records attributed to J Lubinski.

49 records · Page 3Linked to original sources

PubMed1994

Common regions of deletion in chromosome regions 3p12 and 3p14.2 in primary clear cell renal carcinomas.

Nearly all clear cell renal cell carcinomas (RCCs) exhibit loss of alleles on the short arm of chromosome 3. Loss and mutation at the von Hippel-Lindau (VHL) gene at 3p25 probably occurs in most RCCs and, since the VHL gene was recently cloned, data on VHL involvement in RCCs is accumulating. However, the region 3p14-p12, a region that contains the familial RCC-associated t(3;8)(p14.2;q24) chromosome translocation and the small cell lung carcinoma-associated homozygous deletion at 3p13-12, has also been reported to exhibit allele loss in a large fraction of RCCs. In order to focus future studies on potential suppressor genes in the 3p14-p12 region, we have studied allele loss in 30 RCCs with 9 polymorphic simple sequence repeat markers spanning 3p21.1-p12. Partial losses in the 3p21-p12 region were observed, allowing determination of common regions of loss of heterozygosity overlap in 15 RCCs. Results suggested that most RCCs exhibit loss in a region which brackets the t(3;8) familial chromosome translocation at 3p14.2, and some show additional deletions within the U2020 small cell lung carcinoma deletion at 3p12.

Adenocarcinoma, Clear Cell↗

PubMed1993

Characterization of antibodies induced by paternal lymphocyte immunization in couples with recurrent spontaneous abortion.

This study was designed to identify and characterize the allo- and autoantibodies induced following successful paternal lymphocyte immunization to prevent recurrent spontaneous abortion. Firstly the titers of maternal anti-paternal antibodies in women with successful pregnancies as determined by the flow cytometry crossmatch (FCXM) were highly variable; however, in all cases, the initial pre-immunization titers were negative and the post-immunization titers were positive by the FCXM in successfully treated women. Secondly, the specificities of maternal alloantibodies to paternal HLA antigens (immunogen) were evaluated. No all predicted antibodies to mismatched paternal HLA antigens were found by microlymphocytotoxicity (MCX) assays and the specificities varied. Thirdly, antibodies in post- but not preimmunization sera reacted with two lymphoid cell lines, SupT1 and SB; in addition, the rise and fall of the titers of these sera with paternal cells seemed to be reflected with the cell lines by the FCXM. Fourthly, autoantibodies to activated lymphocytes were detected and seemed to correlate with successful immunization since women who had another abortion following immunotherapy lacked these autoantibodies. These findings suggest that the antibody response following successful immunotherapy is complex and needs to be studied further to understand the mechanism of this treatment.

Abortion, Habitual↗

PubMed1991

Gene rearrangements detected by nonradioactive digoxigenin-labeled DNA probes.

The configurations of immunoglobulin, T-cell receptor beta chain and bcl-2 genes were analyzed in lympho-proliferative disorders using nonradioactive digoxigenin-labeled probes. The studies demonstrated the reliability of digoxigenin-labeled probes for the detection of single-copy genes after Southern blotting of genomic DNA: 1 microgram and sometimes even 0.2 microgram of restriction endonuclease-digested DNA could be detected either by JH, C beta or bcl-2 probes. The intensity of the signal was consistently satisfactory, and there was no background problem. Control experiments showed neither false-positive nor false-negative results caused by the use of the nonradioactive detection system.

Blotting, Southern↗

PubMed1991

Patterns of anti-phospholipid antibody specificities.

To determine the importance of assaying for anti-phospholipid (PL) antibodies other than anti-cardiolipin antibodies in patients with putative anti-phospholipid antibody syndrome (APA), 1,513 serum samples from over 399 patients with the potential for thromboembolic disease were tested for IgM, IgG or IgA class antibodies to the following phospholipids: cardiolipin, phosphatidylserine, phosphatidylinositol, phosphatidylethanolamine, phosphatidylglycerol and phosphatidic acid. Non-specific binding was subtracted from total binding of antibodies to each PL to eliminate false positive ELISA results. Only patients whose sera contained antibody levels which were greater than three standard deviations above the means were considered positive. Patients who were positive for anti-PL antibody had antibodies to at least one of six phospholipids tested. Approximately 60% of the positive samples contained antibodies to a phospholipid other than cardiolipin. For IgG class, antibodies to phosphatidylserine were the most prevalent followed by antibodies to phosphatidylethanolamine and cardiolipin. These findings indicate that anti-phospholipid antibody analysis should be performed for more than anti-cardiolipin antibody to detect patients with APA.

Abortion, Habitual↗

PubMed1988

Increased binding of IL-2 and increased IL-2 receptor mRNA synthesis are expressed by an NK-like cell line in response to IL-1.

An NK-like cell line (YTN10 cells) was stimulated with IL-1, and the IL-2R, as detected by flow cytometry analysis using fluorescein-labeled anti-IL-2R (Tac) antibody, increased displaying a dose-response curve in the shape of an inverted "U." This was associated with increases in 1) the number of high affinity binding sites for IL-2 (Kd approximately 45 pM) which increased from 1270 to 4220 sites per cell, and 2) the number of binding sites for anti-Tac antibody, which increased from 999 to 6763 sites per cell. They were both detected by using radiolabeled ligand-binding methods which are one to three orders of magnitude more sensitive than flow cytometry analysis. No binding sites with low affinity for IL-2 could be detected on untreated or treated cells. However, a change was noted in the number of IL-2 binding sites with intermediate affinity (Kd approximately 1000 pM), which increased from 54,000 to 67,000 sites per cell. This binding affinity is equivalent to that of the p70 IL-2-binding protein detected on YT cells and on large granular lymphocytes by other investigators. This suggests that the increase in the Tac peptide was the limiting factor in the combination of the Tac and p70 components to form the high affinity IL-2R. The corollary is that all new Tac molecules were incorporated into these R. The IL-1 treatment also induced an increase in production of Tac mRNA as detected by Northern blots. Comparison of the relative amounts of Tac mRNA by dot blots verified the quantitative difference between treated and untreated cells. These data demonstrate that the IL-1-induced positive regulation of the Tac protein and high affinity IL-2R on YTN10 cells may operate at the level of gene transcription.

Antigens, Surface↗

PubMed1987

Cellular, biochemical, and molecular basis of T-cell senescence.

The elucidation of age-related changes in immune functions is of great importance in light of the rising susceptibility of elderly individuals to infections, the likelihood that immunosenescence might also contribute to the age-related rise in cancer, and the role autoantibodies and immune complexes might play in general physical deterioration of aging individuals through their participation in subclinical chronic tissue damage. An attempt has been made to summarize our present knowledge on immune functions that are vulnerable to aging. It revealed that at the cellular level, all four antigen-responsive immune cells (T cells, B cells, monocytes, and killer cells) are vulnerable to aging, but T cells are perhaps the most vulnerable. Therefore, this article specifically examines the cellular and biochemical T cell-dependent concomitants of age-altered immune functions. One picture that is emerging suggests that at the molecular level, several control points exist along the path of gene expression that could be vulnerable to aging.

Aging↗

PubMed1985

In vitro synthesis of infectious poliovirus RNA.

Replication of the infectious RNA genome of poliovirus is accomplished in cells by the viral RNA polymerase through negative-strand RNA intermediates. Full-length negative-strand poliovirus RNA was synthesized in vitro by transcription of infectious poliovirus cDNA with bacteriophage SP6 DNA-dependent RNA polymerase. When provided with this negative-strand RNA as template, the poliovirus RNA-dependent RNA polymerase synthesized full-length positive-strand molecules. The positive-strand RNAs synthesized in vitro were infectious when transfected into HeLa cells. In contrast, positive-strand copies of poliovirus RNA synthesized in vitro by SP6 polymerase, using a poliovirus cDNA template, were not infectious. Production of infectious positive-strand RNA by the poliovirus polymerase was not observed when magnesium or negative-strand RNA template was omitted from the reaction mixture. Infectivity of the product RNA was not destroyed by DNase treatment. The specific infectivity in HeLa cells of in vitro-synthesized positive-strand RNA was 4 X 10(4) plaque-forming units/micrograms of RNA.

DNA↗

PubMed1985

Purification of a soluble template-dependent rhinovirus RNA polymerase and its dependence on a host cell protein for viral RNA synthesis.

The soluble phase of the cytoplasm of human rhinovirus type 2-infected cells contains an enzymatic activity able to copy rhinovirion RNA without an added primer. This RNA-dependent RNA polymerase (replicase) makes a specific copy of the added rhinovirion RNA, as shown by hybridization of the product to its template RNA but not to other RNAs. The same replicase preparation also contains a virus-specific polyuridylic acid [poly(U)] polymerase activity which is dependent on added polyadenylic acid-oligouridylic acid template-primer. Both activities purify together until a step at which poly(U) polymerase but no replicase activity is recovered. Addition of a purified HeLa cell protein (host factor) to this poly(U) polymerase completely reconstitutes rhinovirus replicase activity. Host factor activity can be supplied by adding oligouridylic acid, suggesting that the host cell protein acts at the initiation step of rhinovirus RNA replication. A virus-specific 64,000-dalton protein purifies with both poly(U) polymerase and replicase activities.

Cell Transformation, Viral↗

PubMed1984

Independent variation in the number of coated pits and of coated vesicles in cultured fibroblasts.

When tissue culture cells were maintained at 37 degrees C in a serum-free medium for 4 hr no change in the number of coated pits could be detected using ultrastructural techniques. However, the number of coated vesicles was highly significantly increased, being 179% more than in the control cultures. If the cells were put back into a medium supplemented with 5% calf serum, the number of coated pits was unchanged, but the number of coated vesicles decreased and returned to the control level within a few minutes. The same results were obtained when using ligands such as Low Density Lipoprotein or alpha-2-macroglobulin which are known to be internalized via coated structures. It is concluded that coated pits appear and disappear at equal rates and that coated vesicles can accumulate independently. It is suggested that this could be due to the presence of a large reserve of soluble clathrin. This pool would have a low turnover rate because cycloheximide did not block coated vesicle accumulation over the period studied.

Animals↗

PubMedDate not supplied

Intermediate filament typing of tumor cells in fine needle aspirates by means of monoclonal antibodies.

Well-characterized monoclonal antibodies directed against different intermediate filament proteins were used in the typing of tumor cells in 30 fine needle aspiration (FNA) biopsy specimens received for routine cytologic examination to assess the value of intermediate filament typing in FNA cytology. Tumors from sites that included liver, large bowel, pancreas, breast, skin, thyroid, thigh and kidney were examined with monoclonal antibodies specific for either all keratins or keratin subsets, vimentin, desmin or specific neurofilament polypeptides. Intermediate filament typing helped to confirm, revise or refine the diagnoses made by light microscopy and provided information of value in the classification of tumors of uncertain origin.

Antibodies, Monoclonal↗

PubMedDate not supplied

Neuroendocrine (Merkel-cell) carcinoma of the skin. Cytology, intermediate filament typing and ultrastructure of tumor cells in fine needle aspirates.

The light and transmission electron microscopic findings and the intermediate filament typing of tumor cells from fine needle aspirates of primary, recurrent and metastatic neuroendocrine (Merkel-cell) carcinoma of the skin are described. The tumor cells in the smears coexpressed keratins and neurofilaments and were characterized by "intermediate filament buttons," i.e., buttonlike fragments of cytoplasm of tumor cells, which could be observed either by staining with intermediate filament-specific antibodies using immunofluorescence or by their appearance in hematoxylin-and-eosin-stained smears. These features may help in the differential diagnosis of fine needle aspirates of neuroendocrine carcinomas of the skin.

Adenocarcinoma↗

PubMedDate not supplied

Diagnosis of metastatic renal cell and thyroid carcinomas by intermediate filament typing and cytology of tumor cells in fine needle aspirates.

Coexpression of keratin and vimentin was found in carcinoma cells of 13 fine needle aspirates of metastatic lesions that showed some cytologic features considered to be consistent with a renal or thyroid origin, but in which a large number of other possible primary sites would have to be taken into account on the basis of the morphologic evidence alone. Immunochemistry thus narrowed the cytologic differential diagnosis to thyroid, renal, endometrial and ovarian carcinomas, which are known to show true coexpression of keratin and vimentin. In most cases, clinical data available at the time of the fine needle aspiration supported the thyroid or renal origin of the carcinoma cells found in the aspirates. In two cases, which lacked significant clinical information, the diagnosis of metastatic renal cell carcinoma was provided on the basis of the combined morphologic and immunocytochemical evidence. In these two cases, computed tomography or ultrasonography revealed kidney tumors, which were removed and confirmed histologically to be clear cell carcinomas.

Adenocarcinoma↗

PubMedDate not supplied

Decisive role of intermediate filament typing of tumor cells in the differential diagnosis of difficult fine needle aspirates.

Thirty-six diagnostically difficult fine needle aspirates from enlarged lymph nodes and malignant soft tissue tumors, containing tumor cells with scanty or no obvious light microscopic features indicative of their differentiation, were assessed by a panel of six cytopathologists. Their diagnoses were recorded and then compared with the definitive diagnosis established by combining the cytologic findings with the results of intermediate filament typing of tumor cells in the smears using monoclonal antibodies specific for each filament type. The results show that use of these antibodies can markedly improve the accuracy of the cytologic diagnosis of tumor type as well as revise or prevent erroneous cytologic diagnoses in difficult cases. This pertains especially to the differential diagnoses of carcinoma versus malignant lymphoma, carcinoma versus malignant melanoma, carcinoma versus sarcoma and squamous carcinoma versus carcinoma of simple epithelia. Intermediate filament typing of tumor cells in aspirates as an objective histogenetic criterium makes the differential diagnosis of the difficult aspirates much more reliable and reproducible, provided that appropriate questions are asked, monoclonal antibodies with well-defined specificities are used and the antigenicity of the intermediate filaments in smears is preserved.

Adult↗