What is pHelper plasmid?
What is pHelper plasmid?
pHelper is a vector of 11.6 KB, carries the adenovirus genes (E2A E4 and VA RNAs required inducing the lytic) for phase of AAV. This vector is cotransfected into the packaging cell line to produce recombinant replication-deficient AAV virions., it is related to packaging adenovirus vector with ampicillin resistance.
What is CIS plasmid?
A cis-plasmid is used to generate the rAAV stocks. In this plasmid, the entire expression cassette is incorporated between two AAV inverted terminal repeats. The construction of cis-plasmid has been problematic be- cause of the high-frequency recombination of the viral inverted terminal repeats.
Does recombinant AAV cause disease in humans?
AAV are not currently known to cause disease. The viruses cause a very mild immune response. Several additional features make AAV an attractive candidate for creating viral vectors for gene therapy, and for the creation of isogenic human disease models.
What is AAV tropism?
Over the past decades, numerous AAV serotypes have been identified with variable tropism. Besides virus capsid, tissue tropisms of AAV vectors are also influenced by cell surface receptors, cellular uptake, intracellular processing, nuclear delivery of the vector genome, uncoating, and second-strand DNA conversion [3].
What is CBA promoter?
Purpose: : The chimeric CMV–chicken ß–actin promoter (CBA) has been utilized extensively as a promoter that supports expression in a wide variety of cells when in recombinant adeno–associated virus (AAV) vectors delivered to retina. Experiments used AAV type 2 and 5 and green fluorescent protein as the reporter gene.
What is triple transfection?
In double transfection, the helper virus genes required for viral replication are either provided by a helper virus infection or cloned onto the same plasmid that contains the rep/cap genes, whereas in triple transfection, the helper genes are cloned into a third plasmid.
What is a viral vector plasmid?
Viral vector and plasmid DNA are tools to transfer genetic material into cells. Viral vectors are generally utilized as vectors for gene therapy. There are various types of vectors, such as lentivirus, adenovirus, adeno-associated virus (AAV), and others, which include herpes simplex virus and chimeric viral vectors.
Does AAV cause disease?
Though AAV is not known to cause disease in humans, precautions must be taken due to the possibility of insertional mutagenesis. In addition, helper viruses used to trigger AAV replication may cause disease. Numerous serotypes of adeno-associated virus with different cell tropisms have been isolated.
What cells target AAV?
In the CNS, while most AAV vectors have a preference for targeting neurons, both naturally-occurring and engineered serotypes have been shown to transduce glia (Figure 1). The tropism of an AAV for a particular cell type is dependent on the interaction of the capsid with cell surface receptors (Lisowski et al., 2015).
What determines AAV tropism?
Adeno-associated virus (AAV) is a small replication-deficient DNA virus belonging to the Parvovirinae family. The AAV capsid (serotype) determines the tissue tropism of the rAAV vector.
What is the difference between phelper and prepcap plasmid?
The AAV transfer vector contains the gene of interest, pHelper plasmid provides Ad helper function genes, and pRepCap encodes AAV Rep and Cap. Need Custom Plasmid Production? For AAV viral vector packaging, you might also need Rep-Cap plasmid and your transfer vector with your gene of interest flanked by AAV ITRs.
What AAV serotypes does the phelper-Kan plasmid support?
The robust virus packaging productivity of the pHelper-Kan plasmid has been tested in almost all AAV serotypes. pHelper-Kan is being used in Vigene’s daily AAV production, for both CGMP grade and research grade batches. Please see the production data below for AAV2, AAV5, AAV6, AAV8, and AAV9 serotypes.
What is the difference between GMP-ready and cGMP-ready plasmids?
Although CGMP-Ready plasmids are not manufactured in a CGMP suite, GMP-Ready plasmids are manufactured in dedicated clean-rooms with mandated changeovers before new production cycles. The GMP-Ready pHelper-Kan plasmid can be used for AAV CGMP manufacturing.
What is the indinduction mode of phelper?
Induction mode: no induction, instantaneous expression pHelper is a vector of 11.6 KB, carries the adenovirus genes (E2A E4 and VA RNAs required inducing the lytic) for phase of AAV.
