The adjuvants present in vaccines have a bad reputation. For most people, they are only unnecessary compounds within a medicinal product. This is a misunderstanding since adjuvants have a critical impact on the success of a vaccination. In the best case scenario, one single vaccination shot would be now sufficient for conferring life-long protection.
Vaccines are one of the most powerful tools against infectious diseases. They protect against an infection by preventing the infection to arise. In a typical vaccine, attenuated or killed pathogens or just some of their sub-cellular components are injected into the body. The immune system responds to those foreign components, producing antibodies and/or killer cells, which are able to fight the pathogen, as well as memory cells. The latter recognize the true pathogen after host infection, thereby promoting a specific and rapid response able to prevent the establishment of a disease.
However, the immune system often reacts only weakly to the attenuated pathogens or their fragments present in a vaccine. Thus, partial or short-life protection is usually stimulated. The adjuvants by themselves do not trigger an immune reaction, but given as components of a vaccine, they modulate and enhance the immune responses elicited, thereby providing a stronger, early and long-lasting protection. While searching for new adjuvants, the vaccine researchers at the HZI have now found the molecule "c-di-IMP".
"This molecule leads to a strong immune response and it is significantly more effective than known adjuvants," says Rimma Libanova, who is examining the molecule in her PhD thesis. To investigate how it works, she vaccinated mice with a harmless protein, which acts as a foreign structure for the immune system of a mouse. Like during a vaccination against a virus or bacterium, an immune response starts against the protein – without the danger of a real infection. One group of mice received the vaccine with the enhancer molecule, the other without the additive. After 42 days, she analyzed the immune reaction of the mice to the foreign protein. "We found a strong immune reaction in mice that received the optimized vaccine. Furthermore, we measured the stimulation of important effector mechanisms, which are key for the success of a vaccination," says Thomas Ebensen, who is working with Rimma Libanova on the new enhancer. Until now, the researchers were only able to show the effect in mice – but they think one step further: "With this new adjuvant, we want to improve already existing vaccines, such as those against influenza or hepatitis. Maybe it also helps to create new vaccines using component that in the past did not promote efficient immune responses using known adjuvants."
"The molecule might also help us to develop new vaccination strategies," says Professor Carlos A. Guzmán, head of the "Vaccinology and Applied Microbiology" Department at the HZI. His department is working on an alternative to the "shot": the snuff vaccination. Here, the vaccine is taken as a nasal spray to work where most pathogens enter the body: at the mucosae. Guzmán highlights, "c-di-IMP enhances also local mucosal immune responses, representing a strong candidate for the implementation of such type of vaccines. This is very important because mucosal vaccines can prevent not only diseases, but also to block infections before they even take place, thereby protecting also non vaccinated contacts against disease."
Original article: Libanova R, Ebensen T, Schulze K, Bruhn D, Norder M, Yevsa T, Morr M, Guzman CA. The member of the cyclic di-nucleotide family bis-(3', 5')-cyclic dimeric inosine monophosphate exerts potent activity as mucosal adjuvant. Vaccine, Volume 28, Issue 10, 2 March 2010, Pages 2249-2258, ISSN 0264-410X, DOI: 10.1016/j.vaccine.2009.12.045.
Dr. Bastian Dornbach | EurekAlert!
Fingerprint' technique spots frog populations at risk from pollution
27.03.2017 | Lancaster University
Parallel computation provides deeper insight into brain function
27.03.2017 | Okinawa Institute of Science and Technology (OIST) Graduate University
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
27.03.2017 | Earth Sciences
27.03.2017 | Life Sciences
27.03.2017 | Life Sciences