Helicobacter pylori (H.pylori) is a gram-negative microaerophilic bacterium that is

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BACKGROUND: The development of an oral typhoid fever vaccine need more effective and having high-efficacy in preventing typhoid fever. The use of liposomes as a vaccine vehicle can be formulated to target a specific location or trigger the release of antigens on its target. β-Glucan derived from Candida albicans cell wall as immunoadjuvant can strengthen the immune response and increases the protection against Salmonella Typhi bacterial invasion. AIM: This study aimed to determine the immune response in typhoid fever mice by administering a combination of AdhO36 S. Typhi liposome vaccine with β-Glucan and determine the protectivity to inhibit bacterial colonization in typhoid fever. METHODS: Mice were divided into five groups include negative and positive control also treatment group. IL-12 was evaluated after 4-h immunization while the other (was IL-12, IL-10, Th1 (IL-2), Th2 (IL-4), and the protective test against bacterial invasion) evaluated after 96-h. RESULTS: IL-12 level in the combination of β-Glucan and AdhO36 groups showed significantly lower than infected groups (p = 0.034), whereas IL-10 level significantly increase (p = 0.0009). The percentage of Th-1 (IL-2) cells significantly lower than infected groups (p = 0.000), this also happened on the percentage of Th-2 (IL-4) cells that significantly lower than infected groups (p = 0.018). The protective test toward bacterial invasion showed no bacterial colonization in all tissues intestine, liver, spleen, and mesenteric lymph node. CONCLUSION: The administration of a combination of liposome containing β-Glucan from C. albicans and AdhO36 S. Typhi has a potential effect on cellular and humoral immune response.

Introduction: Streptococcus pneumoniae (S. pneumoniae) causes pneumococcal disease, which has high mortality and morbidity in children under two years of age, the elderly and immunocompromised individuals. This disease can be prevented by immunization, but the current vaccine, pili protein vaccine (PPV), is less likely to protect children under the age of two and only protects against the serotypes contained in the vaccine. Hence, a new vaccine is needed to enable full protection. The use of bacterial pili proteins may offer an alternative new vaccine. Therefore, the determination of the ability of such proteins to stimulate mucosal immunity with indicator expression of pIgR and s-IgA is required. Materials and Methods: Pili were isolated using the pili bacterial cutter method, and used for nasal vaccination to the rats. TGF-β1, IL-17A, and s-IgA were measured by ELISA while pIgR was examined by immunohistochemistry. Results: This study demonstrated that intranasal immunization with antigen (54 kDa pili protein) and antigen plus adjuvant significantly increased (p<0.05) the expression of TGF-β1. However, the expression of IL-17A increased significantly (p<0.05) only in rats immunized with antigen plus adjuvant. Further analysis demonstrated that intranasal immunization with antigen and antigen plus adjuvant significantly increased (p<0.05) expression of pIgR. Expression of sIgA in nasal lavage significantly increased (p<0.05) in those rats which had been immunized with pili protein plus adjuvant. Conclusion: This study showed that the immünization with S. pneumoniae pili protein increased expression of pIgR and sIgA which are important mucosal immunity components. Therefore, this protein has potency to be developed as nasal vaccination to prevent S. pneumoniae infection.

Background and Aim: The morbidity and mortality of Shigella infections remain a global challenge. Epitope-based vaccine development is an emerging strategy to prevent bacterial invasion. This study aimed to identify the ability of the 49.8 kDa pili subunit adhesin protein epitope of Shigella flexneri to induce an intestinal immune response in mice. Materials and Methods: Thirty adult male Balb/c mice were divided into a control group, cholera toxin B subunit (CTB) group, CTB+QSSTGTNSQSDLDS (pep_1) group, CTB+DTTITKAETKTVTKNQVVDTPVTTDAAK (pep_2) group, and CTB+ ATLGATLNRLDFNVNNK (pep_3). We performed immunization by orally administering 50 μg of antigen and 50 μl of adjuvant once a week over 4 weeks. We assessed the cellular immune response by quantifying T helper 2 (Th2) and Th17 using flow cytometry. In addition, we assessed the humoral immune response by quantifying interleukin (IL-4), IL-17, secretory immunoglobulin A (sIgA), and β-defensin using enzyme-linked immunoassay. Statistical analysis was performed using one-way analysis of variance and Kruskal–Wallis test. Results: Peptide oral immunization increases the cellular immune response as reflected by the increase of Th2 (p=0.019) and Th17 (p=0.004) cell counts, particularly in the CTB_pep_1 group. Humoral immune response activation was demonstrated by increased IL-4 levels, especially in the CTB+pep_3 group (p=0.000). The IL-17 level was increased significantly in the CTB+pep_1 group (p=0.042). The mucosal immune response was demonstrated by the sIgA levels increase in the CTB+pep_3 group (p=0.042) and the β-defensin protein levels (p=0.000). Conclusion: All selected peptides activated the cellular and humoral immune responses in the intestine of mice. Further studies are necessary to optimize antigen delivery and evaluate whether the neutralizing properties of these peptides allow them to prevent bacterial infection.