Rabies Virus (RABV)
Recombinant rabies virus (RV or RABV) allows researchers to advance the study of neural networks and vaccine development by utilizing the unique mechanism of infection found in the virus. Rabies has the advantage of specific neurotropism, restricted transsynaptic spread, ability to specify target cells, and lack of genomic integration.
Types of RABV services offered
- RABV vector cloning using either CVS-N2c or HEP-Flury backbone
- RABV packaging pseudotyped with G protein (N2cG or B19G) or EnvA
Service Details
VectorBuilder has developed backbones from 2 different strains for cloning recombinant RABV: CVS-N2c, primarily used for synaptic tracing, and HEP-Flury, used for vaccine development. See our FAQ for more information about choice of strain. The CVS-N2c backbone contains all of the active genes in the RABV genome, except the glycoprotein G. EGFP or mCherry is typically cloned in place of the G protein, but for the highly attenuated HEP-Flury strain we can offer a vector with all active rabies genes including the G protein, where the marker is cloned between the G and L genes. If you require a custom vector, please contact us and we would be happy to help you with the design support.

Figure 1. (A) RABV CVS-N2c backbone containing the N, P, M, and L genes from the RABV genome. (B) RABV HEP-Flury backbone containing the N, P, M, G, and L genes from the RABV genome.
CVS strain
HEP-Flury strain
Price and turnaround Price Match
Scale | Application | Titer | Volume | Price (USD) | Turnaround |
---|---|---|---|---|---|
RABV pseudotyped with SAD-B19G (EGFP or mCherry) | |||||
Ultra-purified pilot | Cell culture & in vivo | >108 FFU/ml | 100 ul (10x10 ul) | $899 | Please inquire |
Ultra-purified medium | 250 ul (25x10 ul) | $1,399 | |||
RABV pseudotyped with N2cG (EGFP or mCherry) | |||||
Ultra-purified pilot | Cell culture & in vivo | >108 FFU/ml | 100 ul (10x10 ul) | $1,199 | Please inquire |
Ultra-purified medium | 250 ul (25x10 ul) | $2,399 | |||
RABV pseudotyped with EnvA (EGFP or mCherry) | |||||
Ultra-purified pilot | Cell culture & in vivo | >108 FFU/ml | 100 ul (10x10 ul) | $1,599 | Please inquire |
Ultra-purified medium | 250 ul (25x10 ul) | $3,099 | |||
RABV pseudotyped with SAD-B19G, CVS-N2c, or EnvA expressing custom GOl | |||||
Ultra-purified pilot | Cell culture & in vivo | >108 FFU/ml | 100 ul (10x10 ul) | Please inquire | |
Ultra-purified medium | 250 ul (25x10 ul) |
Helper virus
Synaptic tracing requires transduction of both rabies virus and a helper virus expressing the rabies G protein. For EnvA-pseudotyped rabies, TVA expression is also required. More information can be found below.
Price and turnaround Price Match
Scale | Application | Titer | Volume | Price (USD) | Turnaround |
---|---|---|---|---|---|
RABV expressing EGFP or mCherry | |||||
Ultra-purified pilot | Cell culture & in vivo | >108 FFU/ml | 100 ul (10x10 ul) | $899 | Please inquire |
Ultra-purified medium | 250 ul (25x10 ul) | $1,399 | |||
RABV expressing custom GOl | |||||
Ultra-purified pilot | Cell culture & in vivo | >108 FFU/ml | 100 ul (10x10 ul) | Please inquiry | |
Ultra-purified medium | 250 ul (25x10 ul) |
Shipping and storage
Shipping rabies virus requires specific permit(s); please contact us for assistance. Our RABV is stored in HBSS buffer and is shipped on dry ice. Upon receiving, it should be stored at -80°C long term (stable for at least 6 months), or -20°C for use within one week. The shelf life for RABV is approximately one year. Please avoid repeated freeze-thaw cycles of RABV, as this can result in a large titer drop.
Our ultra-purified AAV is stored in a PBS-based buffer. All our AAVs are shipped on dry ice. Upon receiving, it should be stored at -80°C for long term (stable for at least 1 year), or -20°C for short term, e.g. 2-3 weeks. Thawed AAV virus can be stored at 4°C for 1-2 weeks. Although AAV is more stable than many other virus (e.g. lentivirus) and can be frozen and thawed several times with minimal loss of virus activity, it is best to avoid repeated freeze-thaw cycles in practice.
Technical Information
RABV production and quality control (QC)
For virus packaging of the CVS-N2c strain (Figure 2), the plasmid carrying the GOI and helper plasmids containing RABV genes G, N, P, and L are co-transfected into packaging cells together with a T7 RNA Polymerase helper plasmid for viral transcription. The viral proteins produced from the packaging plasmids are required for assembly of viral particles containing the viral genome on the transfer plasmid. Following generation of G-complemented RABV, the virus is amplified using cells stably expressing G protein. When pseudotyping with EnvA for enhanced specificity, the supernatant collected from these packaging cells is then applied to a new dish of cells with stable EnvA expression. Viral particles are then purified through ultracentrifugation. For ultra-purified RABV (in vivo grade), viral particles are further purified by sucrose density gradient centrifugation and concentrated. RABV titer is determined through plaque assay. The workflow below is a general guide for EnvA-pseudotyped RABV; if you would like further information, including about packaging of the HEP-Flury strain, please contact us.

Figure 2. Typical workflow of EnvA-pseudotyped RABV packaging.
For each recombinant RABV produced by VectorBuilder, quality control includes titer measurement, sterility testing for bacteria and fungi, and mycoplasma detection. If the RABV vector encodes a fluorescent protein or drug-selection marker, we perform a transduction test with fluorescence detection or drug selection, respectively. Additionally, for ultra-purified RABV, we routinely perform endotoxin assays to check the endotoxin level. To include endotoxin results in your COA, an extra cost is required. Additional QC services can be provided upon request.
Experimental validation
- Experimental validation
- Transduction validation
Figure 3. AAV helper virus expressing TVA:mCherry and Cre-driven rabies G protein were injected into the dorsal medium striatum (DMS) in D1-Cre mice. EnvA-pseudotyped rabies expressing EGFP was then injected in the same region. The animal was perfused 7 days after rabies virus injection. Magnification: 10x (inset 60x). Left: basolateral amygdala. Right: cortex.
293T 293T-TVA
Figure 4. 293T cells (with and without stable expression of TVA) were transduced with RABV particles expressing EGFP and pseudotyped with EnvA. Images were taken at 48 hours post-transduction. Magnification: 100x. Left: bright field. Right: EGFP.
Rabies virus background and major applications
RABV is a negative-strand RNA virus belonging to the rhabdovirus family. Its genome length is about 12 kb and it can incorporate inserts of 3-5 kb. The virus uses the G glycoprotein to recognize various receptors typically found on the axon terminal of neurons. Once in the axon terminal, the virus is transported in a retrograde direction to the cell body, where replication occurs. Viral replication and transcription occur in the cytoplasm, minimizing both the risk of genomic integration and reliance on host machinery for the virus’s life cycle.
Following replication, the virus is transported to the neuron dendrites where it exits via budding. This highly neurotropic virus only spreads to other cells across chemical synapses, infecting new axon terminals and continuing transport to presynaptic neurons through the peripheral and central nervous systems.
Neural network elucidation
Recombinant RABV is used largely for synaptic tracing of neural networks (Figure 5). Because of the retrograde transport and restriction to transsynaptic spread, specific visualization and modulation of neural connections is possible with RABV. Typically vectors lack G protein so that following infection of a primary neuron, the virus cannot spread to other cells. However, when the virus is introduced to cells with G protein expression (e.g. through AAV transduction), functional virus can be produced and spread to upstream secondary neurons only, facilitating monosynaptic tracing.
Often studying monosynaptic connections in specific neuron subtypes is desired. In this case the EnvA/TVA system allows for viral targeting: RABV can be pseudotyped with envelope protein EnvA that specifically binds to TVA, and vectors expressing TVA and the G protein can be delivered to target primary neurons. This will ensure that only the target cells are infected with the recombinant RABV and allow monosynaptic tracing of all direct inputs.

Figure 5. Design, transduction, and infection of G-pseudotyped and EnvA-pseudotyped recombinant RABV.
Vaccine development
Rabies is a disease with nearly 100% fatality once symptoms appear, driving strong interest in rabies vaccine development. Currently, inactivated RABV is the most commonly used vaccine, but development of replication-competent recombinant RABV-based vaccines is currently underway. The HEP-Flury strain is particularly relevant for this application due to its high attenuation, low pathogenicity, and high immunogenicity.
How to Order
Customer-supplied vectors
If customer-supplied RABV plasmids are used 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 the materials. All customer-supplied materials undergo mandatory QC by VectorBuilder which may incur $100 surcharge for each item. Please note that production may not be initiated until customer-supplied materials pass QC.
Resources
Documents
Flyers Certificate of Analysis (COA)Material Safety Data Sheet (MSDS)
FAQ
RABV is from the same family as VSV but has significant differences: RABV has more specific tropism (neurons only), longer incubation, and absence of cytopathic effects. Its high infectivity specifically in neurons and transsynaptic spread are the primary distinctions for RABV, and further comparisons are listed below.
Lentivirus | Adenovirus | AAV | VSV | RABV | |
---|---|---|---|---|---|
Tropism | Broad | Ineffective for some cells | Depending on viral serotype | Broad | Highly neurotropic |
Carrying capacity | 6.4 kb | 7.5 kb | 4.2 kb | 4.5 kb | 3-5 kb |
Can infect non-dividing cells? | Yes | Yes | Yes | Yes | Yes |
Stable integration or transient | Stable integration | Transient, episomal | Transient, episomal | Transient, episomal | Transient, episomal |
Maximum titer | High | Very high | High | High | High |
Promoter customization | Yes | Yes | Yes | No | No |
Primary use | Cell culture and in vivo |
In vivo | In vivo | Cell culture and in vivo |
Cell culture and in vivo |
Immune response in vivo | Low | High | Very low | High | Low |
- CVS-N2c is more highly virulent, has higher neurotropism, and increased efficiency of transmission. This is an ideal strain for synaptic tracing and studying mechanisms of infection over a shorter time frame.
- HEP-Flury is more highly attenuated, is less pathogenic, and induces a higher immune response. This is an ideal strain for vaccine development and longer-term studies.
Recombinant RABV vectors generated by VectorBuilder are attenuated and can be used in Biosafety Level 2 facilities. Of note, import of RABV into the US requires a valid USDA permit, with which we can provide assistance. CVS-N2c strain rabies viruses are replication incompetent because they lack the envelope glycoprotein G gene, so replication is only possible in cells where the G protein is provided in trans. HEP-Flury strain rabies viruses contain the glycoprotein gene but are highly attenuated with low virulence and pathogenicity.