The Patent Office of the Republic of Poland issued a decision to grant a patent for the invention called Recombinant Virus-Like Particle of Tick-Borne Encephalitis and Its Medical Application. The inventors are: dr hab. Ewelina Król, prof. UG, Marta Zimna, mgr, Gabriela Brzuska, prof. dr hab. Bogusław Szewczyk and Sara Boch-Kminikowska, mgr. The invention was created as part of the NSC Sonata project entitled Tick-Borne Encephalitis Virus - Identification of Mechanisms Useful in Treatment and Prevention, headed by dr hab. Ewelina Król, prof. UG.
Invertebrate-transmitted viral infectious diseases are a major public health problem in all parts of the world. One disease of increasing importance to the EU is tick-borne encephalitis (TBE). TBE is a disorder of the central nervous system that can lead to serious medical complications, including meningitis, encephalitis or myelitis. Tick-borne encephalitis is a severe neurological disease that carries a number of complications that often persist for many years. The causative agent of the disease is the tick-borne encephalitis virus (TBEV). The incidence of TBE has increased by more than 400% in Europe over the past 20 years, making TBE the second most serious tick-borne disease, after Lyme disease. There are five TBEV vaccines available on the market for humans, but they require several doses. In addition, due to the very high cost, vaccination against TBEV is not mandatory, but only recommended for people in risk groups. Therefore, intensive research is being carried out all the time, which would lead to a more effective and cheaper version of the vaccine against this important pathogen. Furthermore, it is necessary to develop a veterinary vaccine, as the consumption of dairy products from infected animals is one of the routes of transmission of the virus to humans.
The invention relates to a potential recombinant vaccine against tick-borne encephalitis virus. An object of the invention is the amino acid sequence of recombinant virus-like particles (VLPs) containing, inter alia, two selected fragments of tick-borne encephalitis virus proteins and additional inserted sequences. VLPs are structures that mimic the virus and are capable of eliciting an immune response against it, but which cannot replicate in the human or animal body and are incapable of causing infection.
‘Through the research work carried out to date, we have obtained a potential vaccine antigen based on recombinant virus-like particles in the Leishmania tarentolae expression system. These particles contain the structural proteins E and prM of TBEV, as well as additional sequences. Our introduction of additional sequences allowed for more efficient overproduction of VLPs and increased immunogenicity. The production of recombinant vaccines does not require working with live viruses, thus reducing the high cost of antigen production. In addition, the use of a protozoan-based system significantly reduces the cost of antigen production,’ explains the Dean of the Intercollegiate Faculty of Biotechnology UG and MUG prof. Ewelina Król, project Principal Investigator.
‘In our in vivo studies, we demonstrated the full efficacy of the obtained antigen in a mouse animal model in collaboration with the Czech Veterinary Research Institute. The results obtained from the challenge experiment confirmed the immunogenicity of the preparation and its strong virus-neutralising properties. All of this gives the preparation a high commercial potential. We are currently working on developing a method for the most effective formulation of the preparation, by testing more adjuvants or the amount of protein in the dose. In addition, we are refining methods to purify the developed antigens from eukaryotic cells on a laboratory scale, which will also be able to be used to purify antigens on a semi-industrial scale,’ adds the scientist.
The implementation of the developed recombinant vaccine at a much lower cost could contribute highly to the availability of vaccination against TBEV. The low cost of the vaccine could also allow it to be used as a veterinary vaccine, which is currently not available.
The invention was developed as part of the NSC Sonata project entitled Tick-borne Encephalitis Virus - Understanding Mechanisms Useful for Treatment and Prevention, headed by prof. Ewelina Król. The invention is also the subject of an application to the European Patent Office (EPO).