|
The function of a gene in biological processes in vivo and its relevance for the pathogenesis of disease can be readily studied by manipulating the genome of animal models (mouse, zebrafish, tadpoles and others). Over the last two decades, the biomedical scientific community has witnessed a (r)evolution in the technical possibilities that have become available to manipulate the genome of these species with great precision, thereby offering unprecedented opportunities to generate disease animal models, elucidate new insight in biological processes in health and disease and propose novel therapeutic concepts and strategies. The latter can be tested by using additional gene manipulation strategies, amongst which gene transfer technologies. The VRC has played a pioneering role in using these technologies to study neurovascular biology: for instance, they published the first knockout mouse models that were deficient of any type of proteinase or key angiogenic factor, and provided the first genetic evidence, using a knockin strategy, that VEGF has neuroprotective activities in vivo.
Transgenesis Commonly used methods to generate transgenic mice (for transgenesis of zebrafish and tadpoles, we refer to the Aquatic Facility) are available at the VRC: micronuclear injection of transgenes in zygotes (plasmids as well as BAC transgenes, engineered via BAC recombineering); as well as a series of technologies based on the use of embryonic stem (ES) cells: homologous recombination of targeting vectors to inactivate genes (knockout using plasmid or BAC targeting vectors), modifiy coding or non-coding sequences of genes (knockin), conditionally inactivate genes in tissue-specific manner (Cre/LoxP or Flp/Flt technology; use of tamoxifen-inducible Cre constructs), conditionally activate genes (targeting of transgenes, preceeded by a floxed stop cassette, into the Rosa26 locus; or tetracycline-inducible rTAT system), zoo of Cre-mouse lines, etc. Blastocyst injection or aggregation of targeted ES cell clones are routinely used to generate chimeric mice, that are then testbred for germline transmission. Tetraploid aggregation is available to generate completely ES cell-derived embryos. Over 100 different transgenic mouse strains have been generated over the last 15 years.
Gene Transfer
The mouse genome can be also manipulated via transferring transgenes to somatic cells, using the following techniques, available at the VRC:
- Non-viral gene transfer: plasmid electroporation (very efficient in skeletal muscle) and hygroporation (liver, kidney) are routinely used to transiently overexpress transgenes or silence (knockdown) endogenous genes using short hairpin RNA vectors in vivo.
- Viral gene transfer: adenoviral gene transfer in skeletal muscle or the heart to induce local transgene expression or systemic injection of recombinant adenoviruses to overexpress transgene products in the circulation (after intravenous injection, the adenovirus will transduce predominantly the hepatocytes, which will then function as a production site of the transgene protein); adeno-associated gene transfer using AAV2 and AAV8 is routinely used to overexpress transgenes or silence endogenous genes in skeletal muscle; retro- and lentiviral gene transfers methods are also available (as used for transduction of neuronal cells).
Pharmacological manipulation
The VRC also produces in house antibodies (often in gene-targeted mice to achieve better antibodies, such as for instance the anti-PlGF antibodies used for the cancer treatment studies) or recombinant proteins (such as for instance VEGF for the ALS treatment studies).
Several knock-out mouse strains are available for collaborations. Feel free to contact
This e-mail address is being protected from spam bots, you need JavaScript enabled to view it
for more information. |
|
Core Facilities 
