MSCV Retrovirus Packaging

Recombinant murine stem cell virus (MSCV) vectors serve as efficient viral vector tools for achieving robust expression of genes of interest in embryonic stem (ES) cells, embryonal carcinoma (EC) cells and hematopoietic stem (HS) cells, along with several other mammalian cell lines. In this retroviral vector system, the presence of a strategically designed 5’LTR derived from the murine stem cell PCMV virus in the MSCV retroviral vector contributes to the transcriptional activation of target genes in pluripotent cell lines. This helps to overcome the restricted expression of target genes in ES and EC cells, typically observed with MMLV retroviral vectors.
VectorBuilder has developed a series of proprietary technologies and reagents that have greatly improved recombinant MSCV production protocols in terms of titer, purity, viability and consistency, especially for the MSCV vector systems used in our vector cloning services. As a result, we have a growing base of highly satisfied customers who come back to us time after time for their MSCV vector cloning and MSCV packaging needs.
Click here to read detailed introduction of our MSCV vector systems
Click here to view citations of our MSCV
Click here to view user testimonials of our MSCV
How do I obtain MSCV packaging services?

Click here to view an example of a finished MSCV vector design
Click here to view an example of a MSCV service proposal
Click here to view instructions on designing a vector on VectorBuilder
Click here to view instructions on placing an order on VectorBuilder
Types of MSCV retrovirus offered

We offer packaging services for VSV-G pseudotyped MSCV retrovirus.

Price and turnaround

Due to our technological advantage, our recombinant MSCV packaging services have the highest quality in the industry and are also faster and more affordable than other suppliers. Price and turnaround time for different scales of MSCV packaging are shown below:

Scale Application Titer & Volume* Price (USD) Turnaround**
Pilot Cell culture >107 TU/ml, 10x25 ul, HBSS buffer $399 8-16 days
Medium Cell culture >107 TU/ml, 10x100 ul, HBSS buffer $599 8-16 days
Large Cell culture >108 TU/ml, 10x100 ul, HBSS buffer $999 8-16 days
Ultra-purified large Cell culture & in vivo >108 TU/ml, 10x100 ul, HBSS buffer $1499 8-16 days

TU = Transduction unit (aka infectious unit)

* Our titer guarantee only applies to vectors for which the region being packaged into virus (from 5’ LTR to 3’ LTR) is below MSCV cargo limit (8 kb). For sizes over this range, it may still be possible to package the vector into virus, but the titer may be reduced. Additionally, we are not able to guarantee titer for the following vectors:

  • vectors containing sequences that could adversely affect the packaging process such as toxic genes (e.g. proapoptotic genes), genes that compromise the integrity of packaging cells or virus (e.g. membrane proteins that cause cell aggregation), and sequences prone to rearrangements or secondary structures;
  • customer-supplied plasmids containing undisclosed sequences or atypical MSCV functional elements (e.g. LTR) that may introduce uncertainties to packaging efficiency.

** Estimated turnaround time is the time from production initiation to completion. It does not include waiting time for any customer-supplied materials (e.g. template DNA or viral vectors), QC of such materials, and transit time for shipping final deliverables to the customer.


If you choose pilot, medium or large scale MSCV packaging, each order includes the following deliverables:

  • Aliquots of custom MSCV at selected scale
  • Free: aliquots of control virus*
  • Free: Polybrene (5 mg/ml, 200 ul)

If you choose ultra-purified large scale MSCV packaging (in vivo grade), each order includes the following deliverables:

  • Aliquots of custom MSCV at selected scale
  • "Add-on" purchase (optional): aliquots of ultra-purified control virus*
  • Free: Polybrene (5 mg/ml, 200 ul)
* The control retrovirus is designed to match the biological application of the custom virus and to be used for testing retroviral transduction. For example, if the custom virus overexpresses a gene, then the control virus provided will be EGFP retrovirus (MSCV retrovirus overexpressing EGFP). Detailed information of the control virus is shown below:
Vector System Control Vector Name Control Vector ID Custom Virus Packaging Scale Control Virus Amount Price (USD)
MSCV gene expression system pMSCV[Exp]-EGFP:T2A:Puro VB190529-1011paj Pilot >107 TU/ml, 100 ul in HBSS Free
Medium >107 TU/ml, 2x100 ul in HBSS Free
Large >107 TU/ml, 2x100 ul in HBSS Free
Ultra-purified large >108 TU/ml, 10x100 ul in HBSS $500
Production, purification and titration

For our MSCV retrovirus manufacturing, the transfer vector carrying the gene of interest (GOI) is co-transfected with our proprietary envelop vector encoding VSV-G and packaging vector encoding Gag and Pol. After a short incubation period, the supernatant is collected and centrifuged to remove cell debris and then filtered. Viral particles are subsequently concentrated with PEG. For ultra-purified MSCV retrovirus (in vivo grade), viral particles are further purified and concentrated by sucrose cushion centrifugation. We use a qPCR-based approach to measure the functional titer of MSCV.

Quality control

For each MSCV produced by VectorBuilder, the quality control includes functional titer measurement, sterility testing for bacteria and fungi, and mycoplasma detection. If the transfer vector encodes a fluorescent protein, we would transduce cells with the virus and detect corresponding fluorescence. Additionally, for ultra-purified MSCV, we routinely sample virus quality using the endotoxin assay.

Customer-supplied vectors

If customer-supplied MSCV retroviral plasmids are needed in packaging, please send them to us following the Materials Submission Guidelines. Please strictly follow our guidelines to set up shipment to avoid any delay or damage of materials. All customer-supplied materials undergo mandatory QC by VectorBuilder which may incur $100 surcharge. Please note that production may not be initiated until customer-supplied materials pass QC.


Please refer to our Vector FAQ for commonly asked technical questions. To get additional information on our offerings, please contact VectorBuilder service team following the contact information here.