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Biomedical subjects

F E Taub

Publications and source records attributed to F E Taub.

10 recordsLinked to original sources
PubMed1992

Detection of c-sis proto-oncogene transcripts by direct enzyme-labeled cDNA probes and in situ hybridization.

Using in situ hybridization and platelet-derived growth factor (PDGF) cDNA probes labeled with horseradish peroxidase, PDGF-A and -B (c-cis proto-oncogene) mRNA transcripts were identified and localized in proliferating cultures. A human retinal pigment epithelial (RPE) cell line and a glial cell line were treated with either transforming growth factor beta-1 (TGFB1), phorbol-12-myristate-13-acetate (PMA), or thrombin from human plasma and compared for their ability to stimulate the production of PDGF-A and -B. Expression of both PDGF-A and -B transcripts were found to be localized predominantly in the cytoplasm of TGFB1-treated RPE cells, with a portion of these cells displaying a hybridization response in the nuclear region. When compared to PMA- and thrombin-treated cells, TGFB1 stimulated the RPE cell line to yield the greatest amount of detectable PDGF mRNA. In addition, the hybridization response observed in TGFB1-treated cells was shown to be RNA dependent.

Cell Division↗
PubMed1991

Detection and identification of Leishmania parasites by in situ hybridization with total and recombinant DNA probes.

In situ hybridization on cultured promastigotes and sandfly smears were performed with nonradioactively labeled total DNA and recombinant DNA probes containing minicircle kinetoplast DNA (kDNA) or nuclear DNA inserts. Total DNA probes lack specificity whereas recombinant nuclear DNA probes work only if they contain repetitive sequences. Minicircle kDNAs of five Leishmania isolates, representative of five Leishmania taxa found in Kenya, were sequenced. Comparison of the sequences showed a 150-bp region with around 80% homology, whereas the rest of the minicircles had about 50% homology. Nevertheless, application of these probes in in situ hybridization assays as tested on Leishmania promastigotes in the vector gave good specificity and hybridization signal. Two types of labeling were tested: incorporation of biotin-labeled dUTP or directly horseradish peroxidase (HRP)-labeled nucleotides. Both techniques provided good sensitivity and signal-to-noise ratio on cultured promastigotes. Hybridization with HRP-labeled kDNA probes gave a superior signal-to-noise ratio if tested on sandfly preparations. This method provided a reliable and fast identification and facilitated the detection of promastigotes in sandflies. The technique presented here may be helpful in rapid identification of Leishmania promastigotes, and thus make epidemiological studies easier and less time consuming.

Animals↗
PubMed1991

Rapid detection of Epstein-Barr virus DNA in clinical samples of oral hairy leukoplakia with HRP-labeled DNA probes and in situ hybridization.

An in situ hybridization technique, using horseradish peroxidase (HRP)-labeled DNA probes containing a portion of the Epstein-Barr virus (EBV) genome, was used to detect EBV DNA in tongue sections and smears from patients with oral lesions resembling the clinical features of oral hairy leukoplakia (HL). Eleven biopsy specimens (six consistent with HL, four normal tongue controls, and one leukoplakia) and 11 tongue smears were evaluated for the presence of EBV, cytomegalovirus (CMV), herpes simplex virus (HSV), and human papillomavirus (HPV) type 16. Following hybridization, six biopsy specimens and 10 tongue smears were found positive for EBV. All biopsy cases were negative for CMV, HSV, HPV-16 and the negative control probe. The specificity of the in situ hybridization assay was 100%. These results suggest that in situ hybridization using HRP-labeled DNA probes may be useful as a rapid diagnostic method for the detection of EBV in tongue sections or smears from patients diagnosed with HL.

Cell Line, Transformed↗
PubMed1991

Culture confirmation of cytomegalovirus and herpes simplex virus by direct enzyme-labeled DNA probes and in situ hybridization.

Using probes consisting of horseradish peroxidase (HRP) directly attached to DNA, scrapings or trypsinized cells from 217 adequate clinical samples were cultured and analyzed in 3 blind studies by in situ hybridization for the presence of cytomegalovirus (CMV) and herpes simplex virus (HSV). Sixty samples were judged inadequate due to insufficient cell numbers; however, this problem was significantly decreased during the course of the study. One hundred and eighteen samples were found positive and 70 samples were found negative for CMV. Scrapings of cultured cells from 29 clinical samples revealed 9 samples which were positive and 20 samples which were negative for HSV. Forty-two additional samples, containing either uninfected cells or cells infected with various strains of CMV, were analyzed for the ability of the HRP-DNA CMV probe to detect such isolates. Twenty samples were positive and 22 negative for CMV. No false-negatives or false-positives were observed for either CMV or HSV. In addition to the specificity noted above neither the CMV nor the HSV DNA probe hybridized to potential contaminants found in clinical specimens.

Cell Line↗
PubMed1990

Type-specific human papillomavirus detection in formalin-fixed, paraffin-embedded tissue sections using nonradioactive deoxyribonucleic acid probes.

DNA probes directly conjugated to horseradish peroxidase have been used successfully to detect human papillomavirus (HPV) types 6/11, 16, and 18 in formalin-fixed, paraffin-embedded tissue sections. By using silver enhancement of a heavy metal-modified diaminobenzidine precipitate, the sensitivity of human papillomavirus detection was significantly increased without compromising specificity. In studies comparing the specificity of the horseradish peroxidase-labeled probe/silver enhancement system to that of a biotinylated-DNA probe/streptavidin-alkaline phosphatase system, the former was found to be superior.

3,3'-Diaminobenzidine↗
PubMed1989

Comparison of in situ hybridization and monoclonal antibodies for early detection of cytomegalovirus in cell culture.

The abilities of each of four diagnostic tests--direct fluorescent monoclonal antibody (direct FA) staining, indirect fluorescent monoclonal antibody (indirect FA) staining, in situ hybridization with biotinylated DNA probes, and in situ hybridization with DNA probes directly linked to enzymatically active horseradish peroxidase-to detect cytomegalovirus soon after culture were compared. Only the indirect FA test and the in situ hybridization method with directly linked HRP-DNA probes provided consistent and reliable cytomegalovirus detection as early as 15 h postinfection.

Antibodies, Monoclonal↗
PubMed1986

Human monoclonal autoantibodies that react with both pancreatic islets and thyroid.

Transformation of human peripheral blood lymphocytes with Epstein-Barr virus and rapid screening on rat insulinoma cells by an enzyme-linked immunosorbent assay were used to identify monoclonal autoantibodies that reacted with human pancreatic islets. Six such monoclonal autoantibodies were isolated and cloned. All six also were found to react with human thyroid. It is concluded that lymphocytes able to make autoantibodies that react with both the pancreas and thyroid are common in the human B cell repertoire.

Animals↗
PubMed1984

Epstein-Barr virus-transformed lymphocytes produce monoclonal autoantibodies that react with antigens in multiple organs.

Peripheral blood lymphocytes from normal individuals and patients with autoimmune abnormalities such as insulin-dependent diabetes mellitus and thyroiditis were infected with Epstein-Barr virus, and the culture supernatants were tested for autoantibodies that reacted with normal tissues. Between 58 and 86% of Epstein-Barr virus-transformed cultures produced immunoglobulin M antibodies, and between 9 and 24% of the transformed cultures produced immunoglobulin G antibodies that reacted with normal tissues. Ten Epstein-Barr virus-transformed clones secreting human immunoglobulin M monoclonal autoantibodies were isolated. Four of these monoclonal autoantibodies were studied in depth and found to react with antigens in multiple organs, including thyroid, pancreas, stomach, smooth muscle, and nerves. It is concluded that Epstein-Barr virus can trigger the production of autoantibodies without infecting the target cells to which the autoantibodies are directed.

Animals↗
PubMed1983

Sequential comparative hybridizations analyzed by computerized image processing can identify and quantitate regulated RNAs.

A method to analyze shifts in the relative abundance of many specific RNAs following any stimulus is presented. Hybridizations of two complex "total" cDNA probes (from the pre- and poststimulus states) to each member of a cDNA library are quantitatively analyzed and mathematically compared by using computer-assisted image processing and statistical analysis of sequential filter hybridizations. Experiments indicate that shifts in abundance between two states can be identified and reproducibly quantitated without purified probes. Direct isolation of recombinant cDNA colonies containing inserts corresponding to regulated RNAs is thus possible. The use of this system is demonstrated for partial analysis of the response in vivo of rat liver to glucocorticoids. Application to other biological systems in which a shift between two states occurs is discussed.

Animals↗