Freund's adjuvant

The Freund's adjuvant, also referred to as Freund's adjuvant, formerly Freund's adjuvant, is a water-in -oil emulsion containing killed microorganisms ( Mycobacterium tuberculosis ). It is a used in the research adjuvant ( adjuvant), which amplifies the desired immune responses in laboratory animals and for immunizations today often is used (as complete Freund 's adjuvant, CFA ), although this is rejected due to the side effects of animal rights activists.

It was developed by Jules T. Friend and Katherine McDermot

Complete Freund 's adjuvant

The complete Freund's adjuvant ( CFA ) contains three essential components:

To achieve the desired effect, careful formulation of the emulsion is essential. The KFA you want to work with must be very well mixed to provide a uniform distribution of the mycobacteria. Then portions of water is added to ensure that the oily phase is the determining. The resulting emulsion is doing every time well mixed; This occurs until a ratio of 1:1 ( oil: water) is achieved. The aim is to provoke water droplets sufficiently small and no air pockets. If this is achieved, maintained an applied onto a cold surface water of the emulsion drops its consistency ( its cohesion).

Incomplete Freund 's adjuvant

The incomplete Freund's adjuvant (IFA ) dispense with the addition of mycobacteria and is / was ( a booster ) used for subsequent injections to enhance the immune response after first injection with KFA.

Advantages and Disadvantages

Freund's adjuvant is still one of the most effective adjuvants for inducing an immune response. An example: For a Experimental autoimmune encephalomyelitis (EAE ) by the injection of peptides of myelin (MBP, PLP, MOG, MAG ) (or pertussis ) can be triggered in complete Freund's adjuvant and enhance the immune response to cell wall components of tubercle bacilli, - and thus ultimately, the mechanisms are explored, leading to the development of multiple sclerosis - a disease (or a group of diseases? ), which has eluded to this day a satisfactory elucidation of disease-causing agents. However, effective medications (such as glatiramer acetate ) can be developed against this disease, a process that took more than 30 years in this case.

Through its pro-inflammatory properties with the formation of abscesses - especially when introduced into the muscle ( intramuscular injection) - and granulomas expected. When administered into the abdominal cavity ( intraperitoneal administration of a ) - mostly in mice and rats - a peritonitis caused. These side effects are dependent on the amount of the introduced and the adjuvant concentration of the antigen and adjuvant, the quality of the produced.

Researchers and animal rights activists were able to at least agree on some places the outlawing some types of administration, so in 1997 with the " list is no longer permissible experiments on the Zurich universities ". This was abolished intraperitoneal injection strongly irritant substances for the production of peritoneal macrophages generally on immunizing with plantar KFA ( in the footpad ) and its intraperitoneal administration further.

Intravenous administration can lead to death of the experimental animal, so that the recommended application limited to a subcutaneous or intradermal application.

Oil formulations are administered instead of initializing vaccination and their replacement by aluminum hydroxide gel, recommended for repeated injections, as equivalent results can be achieved with less stress on the animals.


  • Immunology
  • Pharmaceutical excipient