Table 3.
Characteristics of the vector-based vaccines.
| Vector | Antigens | Host | Challenge | Advantage | Disadvantage | References |
|---|---|---|---|---|---|---|
| S. typhimurium | BLS, Omp19, PrpA, or SOD | Goat | Brucella strain- HJL254 | 1. Safety of vaccine 2. Higher titers of IgG against Omp19 3. Successful delivery of Omp19 4. Higher production of IFN-γ in SOD stimulated goats 5. A significant level of protection with individual antigens in vaccine 6. A strong cell-mediated immune response |
1. Low levels of anti-PrpA and -BLS IgG 2. Limited scope of efficacy of this vaccine (generally < 2 log10 units) 3. Several boosters would be required to achieve a long-term immunity. |
(57) |
| S. typhimurium JOL1800 | Ribosomal protein L7/L12 | Mice | B. abortus 544 | 1. Efficient elicitation of both IgG (IgG1 and IgG2a) and sIgA 2. A significant increase in IFN-γ and IL-4 expression levels 3. A significant increase in both CD4+ and CD8+ expressing cells 4. Enhancing the chance of antigen presentation by Salmonella secreting L7/L12 antigen 5. Clearly inducing both IgG and IgA by a single dose 6. JOL1800 strain induces no mortality in immunized mice due to attenuation by deletion of lon, cpxR, and rfaL genes. 7. Minimum pre-existing lipopolysaccharides (LPS)-specific anti-Salmonella immunity in the host |
NR | (58) |
| S. typhimurium (ST) strain JOL1800 | Cu–Zn superoxide dismutase (SodC) and outer membrane protein 19 (Omp19) | Mice | B. abortus strain 544 | 1. Enhancement of humoral and cellular immune responses and subsequent protection due to the use of sodium bicarbonate antacid formulation 2. PH buffering action around the neutral values could be particularly an advantage for the present vaccine strain to produce an effective immune response. 3. Increasing the number of Salmonella in the intestinal environment 4. Activation of both Th1 and Th2 antibody responses |
NR | (59) |
| HJL228, HJL219, and HJL213 | BSCP31, Omp3b and superoxide dismutase | Mice | B. abortus strain 544 | 1. Significantly inducing higher serum levels of IgG, TNFα, and IFN-γ in group E (immunized with ~1×106 CFU) 2. Significantly inducing higher levels of TNF-α in response to all antigens in groups D (immunized with ~1×105 CFU) and E 3. Significantly inducing higher levels of IFN-γ in response to all antigens in groups D and E than in groups A (immunized with PBS) and B (immunized with Salmonella containing vector only) |
NR | (60) |
| Influenza viral vectors (rIVV) subtypes H5N1 | Omp 16, L7/L12, Omp19, or Cu–Zn SOD | Guinea pigs | B. melitensis 16 M | 1. Inducing a significant protection after intranasal (i.n.) administration of the vaccine 2. Comparability of the protection level induced by conjunctival (c.) administration route to that induced by the commercial B. melitensis Rev1 vaccine 3. Inducing the highest level of protection (vaccination efficiency) against the infection in guinea pigs immunized at doses of 106 EID50 and 107 EID50 (80%) compared with the control group (PBS) after the challenge |
NR | (47) |
| Influenza viral vector (rIVV) subtype H5N1 | Omp 16 and 19, ribosomal L7/L12, and Cu-Zn superoxide dismutase (SOD) | Mice and guinea pigs | B. melitensis 16M | 1. Tetravalent formulation is a safe vector, and its protective efficacy against B. melitensis 16M infection in the prime-boost regimen is comparable to that induced by the commercial B. melitensis Rev1 vaccine in mouse and guinea pig models. | NR | (52) |
| Influenza viral vectors (IVV) subtypes A/H5N1 | Omp16, L7/L12, Omp19, or Cu-Zn superoxide dismutase (SOD) | Sheep and goats | B. melitensis 16M | NR | (50) | |
| Pseudorabies virus | BP26 | Mice | NR | 1. The virus is infective and fatal for most livestock. 2. Its multiple species tropism makes PRV vaccine virus as one of the best vectors to develop bivalent or trivalent vaccines. |
NR | (62) |
| Adenovirus | L7/L12 and BCSP31 | Mice | B. abortus strain CVCC12 | 1. Eliciting higher IgG, IgG1, and IgG2a antibody levels 2. Inducing high levels of IL-12 (Th1-type cytokine) and IL-10 (Th2 type cytokine) |
Weaker efficacy of this vaccine than that of the live A19 vaccine | (55) |
| L. casei | OMP19 | Mice | B. abortus 544 | 1. Increasing serum levels of IFNγ, IL-2, and IL-4 2. Immunization with recombinant L. casei- OMP19 prompts a mixed Th1/Th2 immune response. 3. Significantly inducing a high level of protection 4. Comparability of the protection level obtained with recombinant L. casei to that acquired by the IRIBA Strain Vac Calf vaccine |
NR | (53) |
| L lactis | Cu,Zn superoxide dismutase | Mice | B. abortus 2308 | 1. Inducing protective immune responses at the mucosal level 2. Eliciting agent-specific immunity at the systemic level 3. Induction of systemic and mucosal SOD specific-immune responses in mice orally immunized with L. lactis genetically modified to secrete SOD |
NR | (63) |
NR, not reported; IFN, Interferon; TNF, Tumor necrosis factor; IL, interleukin; Th, T helper; IgG, Immunoglobulin G; Omp, outer membrane protein; SOD, Superoxide dismutase; sIgA, Secretory Immunoglobulin A; CFU, colony-forming unit; PRV, Pseudorabies virus.