Table 3.
Bacterial toxin adjuvant strategies for lactic acid bacteria.
| Adjuvant | LAB | Expression | Antigen | Immune Response | Delivery | Species | Study |
|---|---|---|---|---|---|---|---|
| Cholera Toxin (CT) | |||||||
| CT subunit B | L. casei | Co-administered | Bordetella pertussis (Filamentous Haemagglutinin Adhesin) | Increased IgG | Subcutaneous | Murine BALB/c | Colombi et al. 2006 [90] |
| CT subunit B | L. lactis | Co-administered | Avian Influenza (Hemagglutinin Antigen) | Increased IgG and Intestinal sIgA | Oral | Murine BALB/c | Lei et al. 2011 [84] |
| Increased IFN-γ | |||||||
| Increased Survival to Challenge | |||||||
| CT subunit B | L. casei | Secreted | None | Increased IgG | Intranasal | Murine BALB/c | Okuno et al. 2013 [91] |
| CT subunit A1 | L. casei | Surface-Display | Influenza (Matrix Protein 2) | Increased IgG and BAL sIgA | Oral Intranasal | Murine BALB/c | Chowdhury et al. 2014 [85] |
| Increased IFN-γ (Intranasal) | |||||||
| Increased Protection and Decreased Lung Viral Titer Following Challenge | |||||||
| CT subunit A1 | L. casei | Surface-Display | Influenza (Matrix Protein 2 and Hemagglutinin) |
Increased IgG and BAL and Intestinal sIgA | Oral Intranasal | Murine BALB/c | Li et al. 2015 [86] |
| Increased IFN-γ (Intranasal and Oral) and IL-4 (Intranasal) | |||||||
| Increased protection and decreased lung viral titer Following challenge | |||||||
| Longer Lasting Immune Response | |||||||
| E. coli Heat-Liable Toxin (LT) | |||||||
| LT subunit B | L. casei | Surface-Display | Porcine rotavirus (VP4 capsid protein) | Increased Ocular, Vaginal, and Intestinal sIgA | Oral | Murine BALB/c | Qiao et al. 2009 [92] |
| LT subunit B | L. casei | Surface-Display Secreted | Porcine Epidemic Diarrhea Virus (Core Neutralizing Epitope) | Increased Intestinal, Vaginal, Nasal, Ocular, and Serum sIgA/IgA (Secreted Induced Highest Levels) | Oral | Murine BALB/c | Ge et al. 2012 [87] |
| Increased Neutralizing Antibodies | |||||||
| Increased IFN-γ and IL-4 | |||||||
| LT subunit B and A (LTAK63) | L. casei | Surface-display | Enterotoxigenic E. coli (F4 (K88) fimbrial adhesion FaeG) | Increased IgG and Intestinal, Vaginal, and Nasal sIgA | Oral | Murine BALB/c | Yu et al. 2016 [93] |
| Increased Splenic Lymphocyte Proliferation | |||||||
| Increased Protection to Challenge | |||||||
| LT subunit B | L. plantarum | Surface-display | Avian influenza (hemagglutinin antigen) | Increased Intestinal sIgA | Oral | Murine BALB/c | Jiang et al. 2017 [88] |
| Increased CD4+ T Cell IFN-γ (MLN), IL-4 (MLN, Splenic), IL-17 (MLN, Splenic) and CD8+ T Cell IFN-γ (MLN, Splenic) | |||||||
| Increased PP IgA+ B Cells | |||||||
| Increased Protection to Challenge | |||||||
BAL: Bronchoalveolar lavage; MLN: Mesenteric lymph node; PP: Peyer’s patch.