What is Gc mL?

Physical titer is a measurement of how much virus is present, and is expressed as the number of viral particles per mL (VP/mL), or for AAV as genome copies per mL (GC/mL).

Is VG mL the same as GC mL?

What’s the difference between GC/ml and vg/ml? Both are used interchangeably and it is a qPCR based titer method.

What is infectious titer?

Infectious titer: the concentration of viral particles that can transduce cells. Infectious titers are typically quantified by cell transduction assays. Wild-type AAV2 has been reported to have a near-perfect physical-to-infectious particle ratio of 1:1 (Zeltner et al., 2010).

How is AAV Moi calculated?

For an MOI = 1, the volume (in µl) of AAV particles needed = ((total number of cells per well)/(number of genome copies (GC)/ml)) x 1,000. The MOI used is critical to achieve 100% infection of the target cells without causing major side effects.

What is VG cell?

This analysis leads to a viral genome titer (VG), which is interpreted as the number of viral vector particles carrying the gene of interest. Specific productivity (VG/cell) was calculated by normalizing the viral genome titer to the viable cell density at the time of infection.

What is replication competent AAV?

Replication-incompetent vector particles derived from AAV (adeno-associated virus) have been shown to mediate transfer and expression of heterologous genes (transgenes) into a variety of cells in vivo and in vitro.

What is VG titer?

Perhaps the most critical lot release assay for AAV vector preparations is the AAV vector genome (vg) titer assay, since genome copy numbers are universally used for dosing purposes in both preclinical and clinical studies. The most prevalent method for quantifying AAV vectors is currently quantitative PCR (qPCR).

Which is correct titer or titre?

Titre: Variant spelling of “titer” — the degree of dilution of a substance such as an antibody, reflecting the strength of the solution. Americans spell it “titer” while the English spell it “titre,” French for “title,” derived from the Latin “titulus,” an inscription or label.

What does MOI 10 mean?

Multiplicity of infection (MOI) is a frequently used term in virology which refers to the number of virions that are added per cell during infection. If one million virions are added to one million cells, the MOI is one. If ten million virions are added, the MOI is ten.

What is Tu mL?

Lentiviral titer is measured as Transduction Units per ml (TU/ml). One TU produces one integration event in target cells. To calculate the viral titer, it is first necessary to determine the number of Transduction Units (TU) used to infect the cells.

What is AAV titration?

The AAV Titration protocol can be used to determine the number of genome-containing particles of an AAV prep using SYBR green technology. This protocol was validated using an internal reference AAV of known titer, 100837-AAV1, and by measuring the titer of samples obtained from academic viral vector cores.