Alkyl-polyacrylate esters are strong mucosal adjuvants

Area of Science:

• Immunology
• Polymer Science
• Vaccinology

Background:

• Mucosal vaccines are crucial for preventing infections but often require potent adjuvants.
• Synthetic polymers offer potential as novel adjuvant platforms.
• Polyacrylic acid derivatives were investigated for their adjuvant properties.

Purpose of the Study:

• To evaluate the potency of polyacrylic acid (p[AA]) and its butyl-ester derivative (Butyl16-p[AA]) as mucosal adjuvants.
• To compare their efficacy with existing adjuvants like cholera toxin B subunit (CTB) and liposomes.
• To assess the impact on IgA and IgG antibody responses against various inactivated antigens.

Main Methods:

• Intranasal administration of p[AA] or Butyl16-p[AA] with inactivated antigens (iNDV, iMRC-11, HA/NA, BSA) in mice.
• Two immunizations with a 2-week interval.
• Quantification of IgA-antibody secreting cells (ASCs) in lung, spleen, and serum IgG responses.

Main Results:

• Both p[AA] and Butyl16-p[AA] significantly enhanced IgA responses to all tested antigens.
• Butyl16-p[AA] was more effective than p[AA], CTB, and liposomes.
• Butyl16-p[AA] induced high IgA and IgG responses in lungs and spleen, with up to 10,000 IgA-ASCs/million lung cells observed.

Conclusions:

• Alkyl-esters of polyacrylate represent a novel and effective class of mucosal adjuvants.
• Butyl16-p[AA] demonstrates significant potential for enhancing vaccine-induced mucosal and systemic immunity.
• Further research into polyacrylate-based adjuvants is warranted for vaccine development.