Chitosan and alginate salt as biomaterials are potential natural adjuvants for killed cholera vaccine

Abstract

Chitosan and alginate salts are natural biopolymers that have gained recent attention in the biomedical sectors. Their properties allow them to become potential candidates as safe, cheap, and effective vaccine adjuvants. The present study aimed to enhance the immunogenic response of a current injectable killed cholera vaccine (KCV) using chitosan and alginate salt as natural adjuvants against alum. We tested KCV adjuvanted with alum, chitosan, and sodium alginate in mice. Mice were immunized intraperitoneally with KCV adjuvanted with alum, chitosan, or alginate salt and compared with a control unadjuvanted immunized group. Humoral, cellular, and functional immune responses were evaluated in all groups. The addition of adjuvants, particularly natural adjuvants, to KCV significantly improved the immune response as demonstrated by specific antibody increase, strong proliferation effects, and high protection rate against different challenge doses of cholera strains. Our findings demonstrate that chitosan and alginate salt are superior adjuvants for boosting the KCV immune response and highlights the requirement for further vaccine development.

Immunostimulatory Polymers as Adjuvants, Immunotherapies, and Delivery Systems

“…Chitosan is a positively charged, β1→4 glucosamine-based polysaccharide derived from chitin, a biopolymer that affords structural rigidity in a variety of plants, animals, and fungi. Chitosan drives dendritic cell maturation and induce Type 1 interferon (IFN) responses through a variety of innate immune receptors. − Perhaps most notably, a seminal report by Carroll and co-workers demonstrates that chitosan can activate the STING (stimulator of interferon genes) pathway (see Section ) to trigger APC maturation, costimulatory molecule expression, and Th1-biased adaptive responses. Specifically, chitosan exposure results in mitochondrial stress and reactive oxygen species (ROS) production, leading to an increase in mitochondrial DNA in the cytosol.…”

The main groups of adjuvants and the prospects of their use for the specific prevention of particularly dangerous and other infectious diseases

“…Пептидогликан кислый, выделенный из ростков картофеля и зарегистрированный как лечебный препарат «Иммуномакс», при использовании в качестве адъюванта для синтетической пептидной вакцины против гепатита С в значительной степени увеличивал её иммуногенность [66]. Добавление хитозана (природного биополимера) и альгинатной соли к экспериментальной парентеральной убитой вакцине против холеры значительно улучшало иммунный ответ, о чём свидетельствуют увеличение числа специфических антител, усиление пролиферации иммунокомпетентных клеток и высокая степень защиты от различных доз V. cholerae [67].…”