RESUMEN
Background and Aim: Aeromonas hydrophila infections in fish result in significant financial losses within aquaculture. Previous research indicates black soldier fly (BSF) prepupae provide immunomodulatory benefits through their fatty acids, chitin, and proteins. The study evaluated the impact of hexane extract from black soldier fly prepupae (HEBP) on interleukin (IL)-4 and IL-10 cytokine expression in zebrafish, both infected and uninfected with A. hydrophila. Materials and Methods: Adult zebrafish (aged 4-5 months) was assigned to a negative control group (fed commercial feed), a positive control group (commercial feed + A. hydrophila infection at 107 colony-forming unit/mL), and three treatment groups (T1, T2, T3) that received HEBP at doses of 1000; 2000 and 4000 mg/kg feed for 30 days, respectively. A. hydrophila infection was introduced on day 31 through immersion. Analysis of IL-4 and IL-10 expression in the head kidney trunk region (body without head and tail) through quantitative polymerase chain reaction was conducted on day 33. Results: The HEBP modulated the immune response to A. hydrophila infection at a concentration of 1000 mg/kg feed, as evidenced by an increase in IL-4 and IL-10 expression in the groups not infected with the bacteria. However, these cytokines were decreased in the infected groups. Conclusion: A feed concentration of 1000 mg/kg HEBP was identified as optimal for cytokine modulation. This discovery marks a significant advancement in the development and benefit of a natural extract-based immunomodulator in a zebrafish model, which is potentially immunotherapeutic against bacterial infections in fish for the aquaculture industry.
RESUMEN
A key element in ensuring successful immunization is the efficient delivery of vaccines. However, poor immunogenicity and adverse inflammatory immunogenic reactions make the establishment of an efficient vaccine delivery method a challenging task. The delivery of vaccines has been performed via a variety of delivery methods, including natural-polymer-based carriers that are relatively biocompatible and have low toxicity. The incorporation of adjuvants or antigens into biomaterial-based immunizations has demonstrated better immune response than formulations that just contain the antigen. This system may enable antigen-mediated immunogenicity and shelter and transport the cargo vaccine or antigen to the appropriate target organ. In this regard, this work reviews the recent applications of natural polymer composites from different sources, such as animals, plants, and microbes, in vaccine delivery systems.