VSV

Question 1

Family of VSV

Answer 1

Rhabdoviridae

Question 2

Type and Size of DNA of VSV

Answer 2

Single-stranded RNA genome
11,161 nucleotides in length

Question 3

Which animals can be infected?

Answer 3

Cattle, horses, and swine, resulting in vesicular lesions of the gums, tongue, naso-oral mucosa, teats, and coronary bands

Question 4

Virus transmission routes

Answer 4

Direct contact, aerosol, fomites, and insect vectors, such as mosquitoes, sand flies.

Question 5

Describe the type of capside

Answer 5

Virion envelope, derived from the host cell, is arranged by an external phospholipid bilayer membrane that surrounds a very stable internal ribonucleoprotein core.

Question 6

Main VSV proteins?

Answer 6

Five major proteins:
-N (nucleocapsid or ribonucleoprotein)
-P (phosphoprotein)
-M (matrix protein)
-G (glycoprotein)
-L (large protein or polymerase)

Question 7

Function of G protein

Answer 7

Transmembrane glycoprotein forms spikes on the envelope and mediates cellular recognition and fusion, allowing the viral entry and exit from the cell.

Question 8

Function of M protein

Answer 8

Participates in viral assembly and particle budding

Question 9

Function of N protein

Answer 9

The nucleocapsid core is composed of the viral genome tightly wound around the viral N protein, forming an RNase-resistant core environment

Question 10

Function of P and L proteins

Answer 10

Combine to catalyze RNA-dependent RNA polymerization (RdRp) of genomic RNA and transcription of the mRNAs

Question 11

Transcription and replication mechanisms of VSV

Answer 11

complex and not fully understood, with laboratory and natural populations yielding variable information on genetic adaptability and maintenance.

Question 12

Incubation period ok VSV?

Answer 12

Clinical disease usually develops after a period of 2 to 7 days.

Question 13

Which receptor is using VSV?

Answer 13

Low-density lipoprotein receptor (LDL-R) probably

Question 14

For the rVSV-SARS-CoV-2-msp-SF-Gtc vaccine, function of “IG”

Answer 14

It ensures proper termination and re-initiation of transcription for each gene

Question 15

For the rVSV-SARS-CoV-2-msp-SF-Gtc vaccine, function of “Honeybee Melittin Signal Peptide”?

Answer 15

Msp= to Increase the efficiency of spike protein synthesis, glycosylation, and intracellular trafficking

Question 16

For the rVSV-SARS-CoV-2-msp-SF-Gtc vaccine, function of “TMD”

Answer 16

Transmembrane domain. If used with recombinant protein, The addition of the transmembrane domain of the VSV G protein (Gtc) to the spike protein of SARS-CoV-2, made pseudotype VSV that carry the spike protein more efficiently, and triggered strong immune responses

Question 17

For the rVSV-SARS-CoV-2-msp-SF-Gtc vaccine, function of “HDV”

Answer 17

HDV Hepatitis delta virus ribozyme encoding sequences. The HDV ribozyme self-cleaves RNA immediately downstream of its sequence, creating a well-defined 3’ end. This ensures that the viral RNA transcript produced by the plasmid is of the correct length and sequence for efficient viral packaging or functionality. Improving Viral Particle Formation, Enhanced Stability and Expression

Question 18

For the rVSV-SARS-CoV-2-msp-SF-Gtc vaccine, function of “T7δ”

Answer 18

Bacteriophage T7 transcriptional terminator sequences ( This is a strong promoter commonly used in genetic engineering for efficient expression of genes inserted behind It)

Question 19

Function of Low-Density Lipoprotein Receptors (LDL-R)?

Answer 19

Regulate cholesterol levels in the body

Question 20

Mutations in the VSV for reducing their vector cytopathogenicity? (Vaccine safety)

Answer 20

Three mutations into the M gene

Question 21

Why we need a low amount of VSV for the vaccine?

Answer 21

The attenuated and replication-competent nature of the rVSV vaccine vector allows for lower levels of vaccine needed per vaccination

Question 22

Antigen proteins were expressed in_____at the N-terminus to increase the efficiency of spike protein synthesis

Answer 22

cis

Question 23

How to increase the expression of recombinant proteins it a VSV vector

Answer 23

Using Gtc modification and msp

Question 24

Which is the efficacy of the rVSV Ebola Vaccine?

Answer 24

​The rVSV-ZEBOV vaccine, also known as Ervebo, has demonstrated high efficacy in preventing Ebola virus disease caused by the Zaire ebolavirus. In a 2016 study conducted in Guinea, the vaccine showed 100% efficacy

Question 25

Which is the dosage that they use in the rVSV Ebola Vaccine? And how many vaccines boosters?

Answer 25

​The rVSV-ZEBOV vaccine, marketed as Ervebo, is administered as a single intramuscular injection of 1 mL. This dose contains 20 million plaque-forming units (PFU) of the vaccine. Currently, there is no recommendation for routine booster doses following this initial vaccination

Question 26

Do these rVSV replicative but attenuated vectors produce viremia?

Answer 26

​Yes, the recombinant vesicular stomatitis virus (rVSV) vectors used in the rVSV-ZEBOV Ebola vaccine are replication-competent but attenuated, meaning they can replicate in the host without causing disease. After vaccination, transient viremia—presence of the vaccine virus in the bloodstream—has been observed. In clinical studies, all vaccinated participants exhibited detectable viremia shortly after immunization; however, this viremia was transient and resolved without causing disease. his transient replication is considered a normal aspect of the vaccine's mechanism, contributing to the development of a protective immune response.​

Question 27

Why does the VSV production is made with BHK-21 cells but the titration of them is with VERO cells?

Answer 27

VSV is often produced in BHK‑21 cells because these cells are very efficient at supporting VSV replication and yield high viral titers. However, for titration purposes, VERO cells are preferred because they are highly susceptible to VSV infection (partly due to their limited interferon response) and produce clear, countable plaques or cytopathic effects, which makes quantification more reliable.