• Vaccine Name: Influenza virus DNA vaccine encoding NA from Influenza B virus (B/Ibaraki/2/85)
• Target Pathogen: Influenza virus
• Target Disease: Influenza (flu)
• Vaccine Ontology ID: VO_0011540
• Type: DNA vaccine
• Status: Research
• Antigen: Influenza B virus (B/Ibaraki/2/85) NA neuraminidase
• NA gene engineering:
  • Type: DNA vaccine construction
  • Description: Plasmid pCAGGSP7/NA was constructed by cloning the PCR product NA from B/B/Ibaraki/2/85 influenza virus strain (B/Ibaraki) into the plasmid expression vector pCAGGSP7 (Chen et al., 2001).
  • Detailed Gene Information: Click Here.
• DNA vaccine plasmid:
  • DNA vaccine plasmid name:
  • DNA vaccine plasmid VO ID: VO_0005000
• Immunization Route: Intramuscular injection (i.m.)

Mouse Response

• Host Strain: BALB/c
• Vaccination Protocol: BALB/c mice were immunized twice, 3 weeks apart, by injection of 30 μg of DNA into the quadriceps muscles with a 26-gauge needle under light anesthesia. A pair of electrode needles were inserted 5 mm apart into the muscle to encompass the DNA injection sites, and electrical pulses were delivered using an electric pulse generator (Electro Square Porator T820M; BTX, San Diego, CA). Three pulses of 100 V each, followed by three pulses of the opposite polarity, each pulse lasting for 50 ms, were delivered to each injection site at a rate of one pulse per second (Chen et al., 2001).
• Challenge Protocol: Three weeks after the second immunization, mice were challenged with the mouse-adapted B virus, B/Ibaraki/2/85 (40×50% lethal dose (LD50), 104.3 50% egg-infecting dose (EID50)), by intranasal administration of 20 μl of the viral suspension. This virus rapidly replicates in the lung, causing death in 6–8 days in unimmunized mice (Chen et al., 2001).
• Efficacy: Protection against a lethal influenza B virus infection was examined in BALB/c mice immunized with plasmid DNAs encoding hemagglutinin (HA), neuraminidase (NA and NB) and nucleoprotein (NP) from the B/Ibaraki/2/85 virus. Both HA and NA DNAs conferred complete protection against the lethal challenge in all the tested mouse strains (Chen et al., 2001).