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C Platzer

Publications and source records attributed to C Platzer.

24 records · Page 2Linked to original sources
PubMed1991

Generation of competitor DNA fragments for quantitative PCR.

A convenient and generally applicable method for the generation of competitor DNA fragments for quantitative PCR is described. Using mouse-specific primers, fragments are amplified from DNA of an evolutionarily distantly related species under low-stringency annealing conditions. Because these artificially created fragments contain the mouse primer specific ends, they can be used for the quantification of the mouse DNA amplified by these primers. Competitor DNA fragments that differ in size from the corresponding mouse DNA are selected to distinguish both fragments visually by gel electrophoresis. Competitor DNA fragments were generated for mouse beta-actin, interleukin-1, and tumor necrosis factor (TNF). Co-amplification of beta-actin cDNA for adjustment of equal amounts of input cDNA and subsequently TNF cDNA from lipopolysaccharide (LPS)-activated and nonactivated spleen cells with serial dilutions of the respective competitor DNA fragments allowed a semiquantitative comparison of the ratio of TNF mRNA present in both cDNA samples. Under certain conditions, the competitor DNA fragments can be used to determine the approximate molar concentration of a mRNA.

Animals↗
PubMed1990

Synthesis of bovine leukemia virus antigens in Escherichia coli.

Plasmids were constructed by the use of pEX vectors that encode and express different parts of the bovine leukemia virus (BLV): main core protein p24, nucleic acid-binding protein p12, transmembrane protein gp30, and different segments of envelope protein gp51. Expression of fusion proteins with molecular weights higher than 117 kD for all recombinant plasmids was shown in Coomassie-blue stained gels and by Western blot analysis with rabbit anti-BLV sera. Coupling of a gp51-encoding with a p24-encoding DNA fragment in pEX vectors led to synthesis of a fusion protein that was recognized by monoclonal antibodies directed against gp51 and p24 epitopes. Using another vector, a gp51-encoding DNA fragment of BLV was expressed as a fusion protein with 100 amino acids of the MS2 polymerase. The fusion protein was recognized by monoclonal antibodies directed against gp51.

Animals↗
PubMed1990

Use of monoclonal antibody against major internal protein p24 of bovine leukemia virus in capture ELISA.

A monoclonal antibody (4H4) against the major internal protein, p24, of bovine leukemia virus (BLV) is described. It recognizes a sequence determinant on the p24-molecule and displays high affinity to its antigen. The monoclonal antibody 4H4 was applied in capture ELISA for diagnosis of enzootic bovine leukosis, using crude BLV-preparation as antigen. This test is more sensitive than the immunodiffusion test and at least as sensitive as direct ELISA.

Animals↗
PubMed1990

Identification of an immunodominant region on the isolated bovine leukaemia virus (BLV) major envelope protein gp51 by monoclonal antibodies presumably not exposed during natural BLV infection.

A panel of newly isolated monoclonal antibodies (MoAbs) is described which are specific for bovine leukaemia virus (BLV) envelope protein gp51. Epitope mapping using competition antibody binding assays and binding studies with gp51-related fusion proteins and synthetic peptides show that they are directed against seven independent antigenic determinants. Four of them are unrelated to the epitopes described earlier (Bruck et al., 1982a). We define three binding regions for the MoAbs on the gp51 molecule. The region between amino acids 170 and 217 is highly immunogenic when the isolated protein is used for immunization, and seems to be inaccessible for immune recognition when gp51 is associated with the virus envelope as it occurs during natural BLV infection.

Animals↗
PubMed1990

[Use of a monoclonal antibody against envelope protein gp51 of bovine leukemia virus in a test for the diagnosis of enzootic bovine leukosis].

A highly specific monoclonal antibody (mAb) directed against envelope protein gp51 and effectively bonding the antigen (Ag) on account of its high affinity from an unpurified Ag preparation was chosen for use in a double-sandwich enzyme immuno-assay (EIA) for diagnosis of bovine leukaemia virus (BLV). The epitopes recognised in bovine sera by the gp51-specific antibodies were at the same time properly exposed. Some parameters of major importance to testing were optimised (Ab and Ag quantities, dilution of bovine sera for testing). Preliminary testing of the double-sandwich EIA on selected bovine sera and comparison with both the immunodiffusion test and anti-BLV EIA confirmed its good diagnostic specificity and sensitivity. Hence, this double-sandwich EIA, developed by means of an mAB against gp51, on account of the possibility to use as Ag culture supernatant of the FLC cell line, is a sensitive, low-cost alternative to the anti-BLV EIA Dessau MTP which had so far been used. The double-sandwich EIA is recommended for use in final sanitation for its high analytical and diagnostic sensitivity.

Animals↗