Gregor Siebenkotten

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The availability of genetically altered cells is an essential prerequisite for many scientific and therapeutic applications including functional genomics, drug development, and gene therapy. Unfortunately, the efficient gene transfer into primary cells is still problematic. In contrast to transfections of most cell lines, which can be successfully performed(More)
Immunoglobulin class switching is controlled by cytokines. Thus, interleukin-4 (IL-4) directs class switching to both IgG1 and IgE. Consistent with this are the results reported here on restriction endonuclease analysis of active and inactive alleles of the IgH locus in IgE-producing cells. In cells that were stimulated in vitro by lipopolysaccharide and(More)
Both, in humans and in mice, a major fraction of immunoglobulin E (IgE)-expressing B lymphocytes develops by sequential Ig class switching from IgM via IgG to IgE. This sequential class switch might have functional implications for the frequency and repertoire of IgE+ cells. Here we show that in mutant mice, in which sequential switching to IgE via IgG1 is(More)
Antibody class switching is mediated by somatic recombination between switch regions of the immunoglobulin heavy chain gene locus. Targeting of recombination to particular switch regions is strictly regulated by cytokines through the induction of switch transcripts starting 5' of the repetitive switch regions. However, switch transcription as such is not(More)
IgE is the dominant immunoglobulin isotype involved in type I hypersensitivities in mammals. The heavy chain constant region domains of equine IgE are encoded by a single gene, the Cvarepsilon gene. By restriction analysis of cDNA from 15 unrelated horses, we have now identified two Cvarepsilon alleles, characterised by a Sma I restriction fragment length(More)
We provide a restriction map of the equine c epsilon and c alpha genes as a molecular basis for isotype classification. Human and murine DNA probes were used for identification of homologous equine DNA sequences and for isolation of the equine c epsilon and c alpha genes from a genomic DNA library. A detailed map of the equine 5'-s epsilon/c epsilon-s(More)
Non-viral gene transfer into neurons has proved to be a formidable task. Here, we describe an electroporation-based method that allows efficient and reliable DNA transfer into dissociated neural cells before they are plated and cultured. In hippocampal neural cells derived from either neonatal mouse or embryonic chicken brains, a high transfection rate was(More)
Due to characteristic clinical signs, immunoglobulins of isotype E (IgE) are believed to be involved in several allergic diseases of the horse. To date, closer investigations have been hampered by the fact that neither purified equine IgE nor anti-equine IgE monoclonal antibodies were available for IgE isotype determination. As an approach to solve this(More)
Ig class switch recombination occurs in B lymphocytes upon activation, and is targeted to distinct switch (S) regions by cytokine-mediated induction of switch transcripts spanning the entire S region and the adjacent constant region gene segments. Using a novel type of switch recombination substrate, constructed according to the intron-exon structure of the(More)
BACKGROUND Recombination processes play a crucial role in the functioning of the immune system and are also involved in mutation events that result in various malignancies. So far the study of recombination activity has frequently relied on the use of reporter substrates that are limited by low sensitivity as well as tedious and distorting readout(More)
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