What role does the Adjuvant play in Antibody Development?
Directly immunizing most antigens will lead to a poor immune response and rapid removal of the antigen from the body. To prevent this, the antigen is first combined with an adjuvant, which is a material that helps stimulate and enhance the immune response against the antigen through the creation of a depot effect. By forming a stable emulsion between the antigen and adjuvant, a sustained presentation of the antigen to the immune system is permitted and removal of the antigen from the body is delayed.

Some adjuvants also include components that directly stimulate the immune system. These agents can accelerate development of the immune response against the antigen and ultimately lead to a stronger adaptive response than would otherwise be possible. The adjuvant should also provide the additional benefit of allowing for the use of smaller quantities of the antigen.

In terms of developing antibodies against the antigen, this sustained presentation of the antigen over multiple immunizations is critical for maximizing antibody titers and for allowing affinity maturation of the antibody producing clones against the antigen to complete. As discussed in the Antibody Affinity section, high affinity antibodies will bind quickly and robustly to the antigen, which, combined with the high specificity of the antibodies to the antigen, makes antibodies unparalleled tools for applications such as immunochemistry assays, commercial diagnostic tests and protecting individuals from exposure to harmful pathogens.

Many commercial adjuvants are available, each purporting unique abilities to stimulate the immune response. For development of custom antibodies, the choice of adjuvant will make a difference in terms of maximizing antibody titers and affinity. Many adjuvants break down too quickly, leading to short presentation times for the antigen and lower antibody binding affinity. Or, they require multiple site injections, often with more painful intramuscular or intradermal immunizations that lead to visible abscesses. In the most egregious cases, the adjuvant / antigen mixture is immunized into the footpad, causing significant pain for the animal and preventing it from walking.

Despite what other companies or researchers may say, multiple site injections and painful immunization protocols are not necessary to stimulate a strong immune response. In the course of developing tens of thousands of antibodies and testing all commercially available adjuvants, Pacific Immunology® has developed the premium AdjuLite™ adjuvant, which has consistently proven its ability to elicit a strong immune response with high antibody titers and affinity against the antigen. The superior components used in the AdjuLite™ adjuvant allow for a single subcutaneous immunization that permits maximum exposure duration of the antigen to the immune system while minimizing quantities of the antigen required. At the same time, immunization stresses are minimized for the animal and virtually no injection site abscesses or visible irritation are observed as a result of immunizations. AdjuLite™ adjuvants are used for all custom antibody projects run at Pacific Immunology® and full details on the AdjuLite™ line of adjuvants can be found on our Products page.

Next: Custom Antibody Development