Evaluation of Porphyra oligosaccharides/docosahexaenoic acid-based emulsion as mucosal vaccine adjuvant against vaginal Candida albicans infection in mice

10.29822/JFST.202209_49(3).0001

Wei-Chung Tsai；Ming-Hsi Huang；Chung-Hsiung Huang

Candida albicans ； docosahexaenoic acid ； emulsion ； mucosal vaccine adjuvant ； Porphyra oligosaccharides

臺灣水產學會刊

49卷3期（2022 / 09 / 01）

145 - 156

英文

Candida albicans is an opportunistic fungal pathogen that readily infects immunodeficient hosts. It has been found that approximately 75% of women experience vaginal candida infection at least once in their lifetime. Moreover, drug-resistant strains of C. albicans have been identified in humans. Therefore, it is imperative to develop novel strategies for preventing C. albicans infection. Vaccination is known to stimulate adaptive immune responses against pathogens by mimicking the infection process within the body. Interestingly, around 80% of immune cells reside in the mucosa-associated lymphoid tissues, indicating that the mucosa represents an ideal route for vaccination. Emulsions have already been employed for vaccine delivery, and the immunomodulatory effects of Porphyra polysaccharides and docosahexaenoic acid have been reported. In this study, we formulated emulsions containing either Porphyra polysaccharides or oligosaccharides combined with docosahexaenoic acid, aiming to develop mucosal vaccine adjuvants. We investigated the preventive effect of these adjuvanted vaccines in a murine model of vaginal C. albicans infection. Intravaginal vaccination with heat-killed C. albicans (HK-CA) adjuvanted with Porphyra oligosaccharide-containing emulsion resulted in enhanced local antibody production and elevated IL-17 production. Importantly, we observed significantly reduced mucosal damage and milder cell infiltration in the vaginal tissues of vaccinated mice following C. albicans challenge. Taken together, our findings suggest that Porphyra oligosaccharides/docosahexaenoic acid-based emulsion holds potential as a mucosal adjuvant for intravaginal C. albicans vaccine development.