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W Uckert

Publications and source records attributed to W Uckert.

45 records · Page 3Linked to original sources
PubMed1982

The application of a sepharose bead immunofluorescence assay and a solid-phase radioimmunoassay to the bovine leukemia virus system.

Several fluorescence assays with bovine leukemia virus (BLV) conjugated to activated Sepharose 4B were used for the detection of BLV and anti-BLV antibodies. These tests were compared with a solid-phase radioimmunoassay and found to be in the same sensitivity range. Sepharose bead immunofluorescence assay and solid-phase radioimmunoassay can be applied to the diagnosis of BLV infection in cattle.

Animals↗
PubMed1981

Type D retroviruses from human cells do not contain a minor glycoprotein shared by old world monkey type D viruses.

The protein patterns of type D retroviruses isolated either from permanent human cells (HeLa virus, HeLa V, and HEp-2 virus, HEp-2V) or from spectacled langur (langur virus, LV), an Old World monkey, were investigated using sodium dodecyl sulfate polyacrylamide gel electrophoresis. Labeling with 14C-amino acids and 3H-glucosamine revealed for each of these isolates five polypeptides with molecular weights of 10,000, 12,000, 15,000, 25,000 and about 68,000 and identified the 68,000 D-protein as a glycoprotein. An additional glycoprotein with a molecular weight of 20,000 (gp20) was resolved in LV similarly as in previous studies with Mason-Pfizer monkey virus. However, in accordance with our recent analysis of a third type D isolate from human cells (PMFV), gp20 was not detectable in both HeLaV and HEp-2V regardless of the cell line in which they were grown. Thus, it appears that the type D virus isolates from human cells are slightly distinct from the presently known type D retroviruses of Old World monkeys. The relevance of this finding to the origin of the human isolates, however, remains to be shown.

Animals↗
PubMed1981

[Some parameters of the production of a type D retrovirus (PMFV) in human cells (author's transl)].

The production of a type D retrovirus (PMFV) was analysed using different conditions of cultivation. Both in cell culture flasks and in roller culture bottles with discontinuous change of medium an increase of virus amount was determined within 12 h after seeding of virus-infected cells. Then the virus production considerably fluctuated around an apparent mean value until the end of the experiment at 56 h. In case of a continuous change of cell culture medium in roller bottles a maximum of virus production was measured at a retention time of 24 h of cell culture medium. The production of PMFV could be essentially increased when virus-producing cells were co-cultivated with non-infected cells of the same type.

Cell Line↗
PubMed1980

The protein pattern of PMF virus, a type-D retrovirus from malignant permanent human cell lines.

The protein pattern of a type-D retrovirus (PMFV) isolated from and propagated in human cell lines has been investigated using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Staining with Coomassie blue and labeling with 14C-leucine/14C-lysine revealed five viral polypeptides with molecular weights of 10,000, 12,000, 15,000, 25,000, and 68,000. The 68,000 D-protein was shown to be a glycoprotein by incorporation of 3H-glucosamine and the 15,000 D-protein was identified as a phosphoprotein. By comparing PMFV with the closely related Mason-Pfizer monkey virus (MPMV) in co-electrophoresis experiments no clear difference was detected in viral 14C-leucine/14C-lysine profiles. The viruses differ, however, with respect to their glycoprotein patterns. A glycoprotein corresponding to the gp20 of MPMV has not been detected in PMFV irrespective of the cell line used for propagation of viruses.

Cell Line↗
PubMed1979

Proteins of bovine leudemia virus: p. 15 is the major phosphorprotein.

Sodium dodecylsulfate-polyacrylamide gel electrophoresis of bovine leukemia virus (BLV) grown in fetal lamb kidney cells in the presence of 32P-phosphoric acid showed that the slightly basic 15000 D protein (pp 15) is the major phosphorylated component of the virus. This result further distinguishes BLV from mammalian type C viruses which possess acidic major phosphorproteins.

Animals↗
PubMed1976

[Elimination of a paramyxo-type virus from oncornavirus-producing human cell lines (author's transl)].

A virus of the paramyxo-type was eliminated from cell-free material of human oncornavirus-producing cell lines (PMF). After transmission of this paramyxovirus-free inoculum to a human permanent cell strain (Tu 197/Tr 1) oncornaviruses were permanently formed and no paramyxoviruses could be detected. The paramyxovirus-free, oncornavirus-producing PMF-39 cell line could be established after inoculation of the TU 197/Tr 1 line with cell-free material containing both oncorna- and paramyxovirus diluted 1 to 1000. A second way of elimination of the paramyxovirus was the treatment of cell-free material containing both viruses with antisera against paramyxovirus. In the Tu 197/Tr 1 line inoculated with such material only oncornaviruses were formed. The second paramyxovirus-free oncornavirus-producing cell line was designated PMF 50.

Animals↗
PubMedDate not supplied

MLV-10A1 retrovirus pseudotype efficiently transduces primary human CD4+ T lymphocytes.

BACKGROUND: Previously, we showed that retroviral vectors pseudotyped with the envelope of the amphotropic murine leukemia virus 10A1 (MLV-10A1) more efficiently transduce primary human CD8+ T lymphocytes when compared with other A-MLV, gibbon ape leukemia virus (GaLV) and feline endogenous retrovirus (RD114) vector pseudotypes. For the success of several gene therapeutic approaches (ADA, HIV) it is important to effectively transduce primary human CD4+ T lymphocytes. METHODS: We have used retroviral vectors encoding the enhanced green fluorescent protein (EGFP) as a marker gene and carrying envelopes of MLV-10A1, A-MLV and GaLV and have analyzed the transduction efficiency of both human CD4+ T cell lines (CEM, H9, HUT78, J16) and primary human CD4+ T lymphocytes using a RetroNectin-assisted transduction protocol and virus-containing supernatant. RESULTS: In CD4+ T cell lines the MLV-10A1 vector pseudotype was most effective and infected up to 85% of cells which then stably expressed GFP over time. MLV-10A1 was also superior and infected approximately 32% of primary human CD4+ T lymphocytes in comparison to GaLV (18%) and A-MLV (12%). The superior efficiency of MLV-10A1 for the transduction of CD4+ T cells correlates with the longer half-life of this pseudotype in comparison to A-MLV and, as previously shown by interference analysis, with the usage of both the A-MLV (Pit2) and the GaLV receptor (Pitl) for cell entry. CONCLUSIONS: MLV-10A1 is a suitable vector for transferring genes with high efficacy into primary human CD4+ T lymphocytes. The use of MLV-10A1 pseudotyped vectors should make it easier to obtain a sufficient number of gene-modified T lymphocytes for an adoptive transfer.

Animals↗
PubMedDate not supplied

Retrovirus-mediated gene transfer of tumor necrosis factor alpha into colon carcinoma cells generates a growth inhibition.

Retrovirus-mediated gene transfer was employed to introduce two different cDNAs of the human tumor necrosis factor alpha gene (TNF) into colon carcinoma cell lines either sensitive (LoVo) or resistant (LS174T) to the external addition of TNF. The TNF variants differed in their 5'-sequences (HTNF: authentic TNF cDNA, SPTNF: TNF cDNA with a signal sequence of the IgG heavy chain). The integration of TNF-specific DNA into the genomic DNA, the expression of TNF-specific mRNA and the translation into TNF protein was shown by Southern-, Northern- and Western analysis with TNF-specific DNA- and RNA probes and anti-TNF-antibodies, respectively. Neomycin selected tumor cell clones expressed biologically active TNF up to 40 pg/ml. As shown in a growth assay, both variants of TNF caused an up to 80% growth inhibition in colon carcinoma cells. Furthermore, the cells constitutively producing TNF had a distinguishable morphological appearance and a reduced colony growth in soft agar compared to the parental cells. The subcutaneous injection of 1 x 10(6) TNF-expressing tumor cells into nude mice resulted in a reduced tumor progression in comparison to the controls.

Animals↗