Unravelling how adjuvants work, and what their roles are in vaccination and allergy

Abstract

The development of safe and effective vaccines is essential to tackling a variety of infectious diseases. Vaccines fall into a variety of different types, depending on how they are produced. The inclusions of live attenuated, inactivated, toxoid, subunit or conjugate vaccines contain key antigens which are used in the vaccines to encourage the immune system to mount an immune response. This response will eventually trigger the creation of targeted memory B cells that persist and can quickly multiple and tackle future interactions with the disease agent. This is the cornerstone of our adaptive immune system, protecting us against getting many diseases more than once. Vaccines often contain more than just the antigen. They also commonly contain a facilitating agent known as an adjuvant. Adjuvants enhance the effect of the vaccine, making it more likely to work and to work well, however, it has long been thought that they themselves confer no immunity if presented to the immune system without the antigen. One of the biggest mysteries in immunology is how exactly adjuvants function. They certainly do function, often making the difference between an ineffectual vaccine and one that can help tackle a disease. However, answering the question of 'how?' may well prove key to the development of better vaccines and even treatments in other fields of human disease. Investigating the mode of action of adjuvants is Dr Etsushi Kuroda, Senior Researcher at NIBIOHN, Japan. He works in the Center for Vaccine and Adjuvant Research under Dr Ken J. Ishii in a large lab with multiple researchers focussing on a different aspect of adjuvants. Kuroda's field of interest is the role of pollution particulates as adjuvants to allergy and asthma. Kuroda explains his area of research in greater detail: 'Particle pollutants that we focused on are also thought to be adjuvants and induce inflammation when they are inhaled. There are pros and cons in adjuvants, and excessive activation of immune cells by adjuvant might induce immune-related diseases such as allergic inflammation.'