Adjuvants



Vaccines combined with adjuvant systems have been proven to enhance immunogenicity (Perrie et al. 2008). .

**__What is an adjuvant?__** An adjuvant as an agent that can stimulate an immune system while having few if any direct effects when given by itself.

**__What do adjuvants do?__** The role of an adjuvant is to provide protection by preventing the antigen from degrading and also to make it easier for antigen-presenting cells to locate and engulf antigens (Perrie et al. 2008). .

**__How do they do this?__** Adujuvants stimulate the immune system to respond to the vaccine more vigourously, thus providing increased immunity to a particular disease. They mimic specific sets of conserved molecules called PAMPs, which include: - liposomes - lipopolysaccharide (LPS) - molecular cages for antigens - components of bacterial cell walls - endocytosed nucleic acids (such as double-stranded RNA (dsRNA)) - single-stranded DNA (ssDNA) - unmethylated DpG dinucleotide - containing DNA An adjuvant with a vaccine can greatly increase the immune response to the antigen by augmenting the activities of dendritic cells (DCs), lymphocytes, and macrophages by mimicking a natural infection.

**__What adjuvants are used?__** **Aluminum salts -** these are the most common adjuvants used in vaccines for humans. **Organic adjuvants** - these are most commonly used in animal vaccines. **Oil-based adjuvants** - these are most commonly used in veterinary vaccines.  Factors effecting immunogenicity  Autoimmune disorders : Ultraviolet radiation    Immunosuppression : Adjuvants Contributed by Sidharsha Naidoo
 * Virosomes -** these are adjuvants with carrier systems ( Clements 2002).