• Vaccine Name: Non-typeable H. influenzae rLP4/rLP6 and Moraxella catarrhalis UspA2 protein vaccine
• Target Pathogen: Haemophilus influenzae
• Target Disease: Meningitis
• Vaccine Ontology ID: VO_0000473
• Type: Subunit vaccine
• Antigen: NTHi rLP4/rLP6 and M. catarrhalis UspA2 proteins(Mason et al., 2004)
• Pal gene engineering:
  • Type: recombinant
  • Description: The P6 protein is an integral outer membrane protein and, as a peptidoglycan-associated lipoprotein , is thought to be necessary for the integrity of the bacterium’s outer membrane.(Mason et al., 2004)
  • Detailed Gene Information: Click Here.
• yscF gene engineering:
  • Type: recombinant
  • Description: The P4 protein is an integral outer membrane protein that has a role in acquiring hemin and nucleosides.(Green et al., 1991)
  • Detailed Gene Information: Click Here.
• Adjuvant:
  • Adjuvant name:
  • VO adjuvant ID: VO_0001239
• Preparation: Recombinant nontypeable H. influenzae LP4 (rLP4) and LP6 (rLP6) were expressed in E. coli strain BLR and purified (Mason et al., 2004). M. catarrhalis UspA was purified from outer membrane vesicles prepared from isolate O35E (Mason et al., 2004).
• Description: Nontypeable Haemophilus influenzae (NTHi) and Moraxella catarrhalis are two of the leading causes of bacterial otitis media. The immunodominant exposed surface molecules of NTHi, including lipooligosaccharide (LOS) and outer membrane proteins, are extremely variable antigenically and infection with one strain provides immunity only to that strain. Thus, NTHi vaccine efforts have focused on antigenically conserved outer membrane protein such as the P4 and P6 proteins and LOS-conjugates. While the surface of M. catarrhalis appears to be much less antigenically variable, vaccine efforts have also focused on conserved outer membrane proteins and LOS. The ubiquitous cell surface protein A (UspA) of M. catarrhalis is a particularly interesting vaccine candidate (Mason et al., 2004).

Human Response

• Vaccination Protocol: At weeks of 0, 1, 3 and 5, groups of 10, 6 to 8-week-old, female BALB/c mice were immunized intranasally with 30 μg purified rLP4/rLP6/UspA2 (10 μg each protein) mixed with or without 10 μg RC529-AF in 15 μl of volume. Control mice received Delbecco's phosphate buffered saline (D-PBS) alone or D-PBS with 10 μg RC529-AF, again in 15 μl volumes. The vaccine was delivered by pipette in a volume of 7.5 μl per nostril. The pipette was positioned so that the tip touched the opening of the nostril and liquid was drawn into the nasopharynx during breathing. Immediately following immunization, mice were placed in a supine position for 3~5 min (Mason et al., 2004).
• Immune Response: These proteins combined with RC529-AF administered intranasally to mice elicited (1) significantly increased rLP4/rLP6/UspA2 protein-specific circulating IgG and IgA antibody responses; (2) local rLP4/rLP6/UspA2-specific IgA responses in the respiratory tract. The serum IgG subclass distribution was predominantly IgG2a, representing a Th1 response.
• Challenge Protocol: Two weeks after the final immunization, animals were challenged intranasally with approximately 1 million colony forming units (CFU) of NTHi strain SR7332.P1. Mice were anesthetized, and 5 μl of bacteria were administered into each nostril. Twenty minutes after the challenge, an aliquot of the bacterial suspension was diluted in D-PBS and plated onto brain-heart infusion XV (BHI-XV) agar to determine the actual inoculum. Three days after challenge, nasal turbinates were harvested, weighed, homogenized, serially diluted and plated on BHI-XV plates containing 100 μg/ml streptomycin. Following incubation of plates overnight, colonies were counted, and CFU per gram of nasal tissue were determined (Mason et al., 2004).
• Efficacy: These proteins combined with RC529-AF administered intranasally to mice elicited more than a two log reduction of nasal colonization of NTHi strain SR7332 from the nasal tissues of mice. The antiserum also exhibited bactericidal activities to several strains of M. catarrhalis.