Freund’s Adjuvant was first developed in the 1940s by Jules Freund. It is largely used in immune research, particularly in animal immune research. It is an aqueous solution of antigens, which is used by mixing an equal proportion of water and oil, usually paraffin oil or vegetable oil. It becomes an antigen emulsion when an emulsifier, such as lanolin or leaf tween 80, is added to the mixture. While Complete Freund’s Adjuvant contains slaughtered Mycobacterium tuberculosis, the incomplete version of Freund’s adjuvant does not include the bacteria.
Incomplete Freund’s adjuvant is usually prepared with a mixture of 2 parts of liquid paraffin and one part of lanolin, but the ratio may be 1-5:1, according to the need. An incomplete adjuvant can be transformed into a complete Freund’s adjuvant with the final concentration of 2-20 mg/ml of BCG or killed Mycobacterium tuberculosis. Usually, during the first injection, emulsification is used with 1/2 volume of FCA and antigen, and no adjuvant is used for the subsequent second and third inoculation. The antigen volume can be increased by 10 to 20 times without adding an adjuvant.
The purpose of using Freund’s Adjuvant is to get antigens continuously, which are essential for inspiring a strong, persistent immune response. It is because the mycobacteria in Complete Freund’s adjuvant are capable of attracting macrophages and other cells to the inoculation spot, thus improving the immune response. It makes Complete Freund’s Adjuvant appropriate to use for the first immune response, as it works as a booster and reduces side effects.
Although there are several types of adjuvants available on the market, Freund’s Adjuvant stands separate from them. This is for the reason that it offers unique benefits to users. Freund’s Adjuvant is considered one of the most effectual adjuvants, making it indispensable for antibody manufacture protocols and study. Additionally, the adjuvant is capable of stimulating antibody production through two effective different mechanisms, such as the unfocused immune potentiation of macrophages and the depot effect. Both types of Freund’s Adjuvant have been used for over 70 years in the research fields. These adjuvants are mostly used for enhancing the immune response of the animal such as mouse and rabbit to an antigen.
Freund’s Adjuvant A Powerful Tool in Vaccine Development
As scientists continue to work towards developing effective vaccines for a range of infectious diseases, the role of adjuvants in vaccine development is becoming increasingly important. Freund’s adjuvant, named after its discoverer Jules T. Freund, is one of the most commonly used adjuvants in the field. In this article, we will explore the history and science behind Freund’s adjuvant, its mechanism of action, its advantages and disadvantages, and its role in modern vaccine development.
1. What is Freund’s Adjuvant?
Freund’s adjuvant is a mixture of two substances: an oil, typically mineral oil, and killed mycobacteria. It is used to enhance the immune response to a vaccine antigen, meaning that it helps to boost the body’s ability to recognize and respond to a specific pathogen. Freund’s adjuvant is administered along with a vaccine antigen to elicit a stronger and more long-lasting immune response.
2. History of Freund’s Adjuvant
Freund’s adjuvant was first developed by Jules T. Freund in the 1930s. Freund was a Hungarian-born immunologist who worked at the Rockefeller Institute for Medical Research in New York. He developed the adjuvant as a means of enhancing the immune response to injected antigens in experimental animals. Freund’s adjuvant was first used in humans during World War II as part of an effort to develop vaccines against infectious diseases that were prevalent among troops.
3. Types of Freund’s Adjuvant
There are two main types of Freund’s adjuvant: complete and incomplete. Complete Freund’s adjuvant (CFA) contains both the oil and the killed mycobacteria, while incomplete Freund’s adjuvant (IFA) contains only the oil. CFA is more potent than IFA, but it is also more likely to cause adverse reactions in vaccinated individuals.
4. Mechanism of Action
The mechanism of action of Freund’s adjuvant is not fully understood, but it is thought to work by several different mechanisms. First, the oil component of the adjuvant forms a depot at the site of injection, which slows down the release of the antigen into the bloodstream. This allows the antigen to be taken up by antigen-presenting cells (APCs) and presented to T cells over a longer period of time. Second, the mycobacteria component of the adjuvant activates APCs, leading to increased cytokine production and activation of the adaptive immune response.
5. Advantages of Freund’s Adjuvant
Freund’s adjuvant has several advantages that make it a useful tool in vaccine development. First, it is a potent adjuvant that can enhance the immune response to a wide range of antigens. Second, it is relatively easy to prepare and administer. Finally, it has been extensively studied and has a long history of safe use in animals and humans.