Adjuvants--a balance between toxicity and adjuvanticity

Area of Science:

• Immunology
• Vaccinology
• Pharmacology

Background:

• Adjuvants have enhanced immune responses in immunology and vaccination for over 60 years.
• Adjuvants exhibit diverse chemical properties, mechanisms of action, and side effect profiles.
• Side effects can stem from unintended immune stimulation or general adverse drug reactions.

Purpose of the Study:

• To review the characteristics and applications of various adjuvants in vaccination.
• To discuss the variability in adjuvant efficacy and safety profiles.
• To highlight the ongoing development and considerations for novel adjuvants in human use.

Main Methods:

• Literature review of adjuvants used in experimental and practical vaccination.
• Analysis of the chemical nature, mode of action, and side effects of common adjuvants.
• Examination of emerging adjuvant technologies and their potential for human application.

Main Results:

• Common human adjuvants include aluminium salts, with oil emulsions, bacterial derivatives, and liposomes also explored.
• Newer adjuvants like monophosphoryl lipid A, ISCOMs, and SAF are under consideration for human use.
• The selection of adjuvants involves a trade-off between adjuvanticity and acceptable side effect levels.

Conclusions:

• Adjuvant selection for human vaccines requires balancing immune-boosting capacity with a low incidence of adverse events.
• Continued research into novel adjuvants aims to improve vaccine efficacy and safety.
• The field is evolving, with ongoing evaluation of advanced adjuvant formulations.