The first data on a new Italian vaccine candidate against Covid-19 are promising. It is called ‘LeCoVax2’ and was developed in the laboratories of the State University of Milan, in collaboration with the startup VisMederi Research srl based in Siena. The first preclinical experimental study, conducted on a mouse model – announced by UniMi – demonstrates the “efficacy” of the product “in inducing antibodies capable of neutralizing the Sars-CoV-2 virus”. The “encouraging” result, they explain from the Milanese university, comes from a work coordinated by Claudio Bandi, Sara Epis and Gian Vincenzo Zuccotti of the ‘Romeo and Enrica Invernizzi’ pediatric research center of the Statale, in synergy with Emanuele Montomoli, scientific director of VisMederi Research and professor at the University of Siena, which has already translated into two patents filed in February. “LeCoVax2 has innovative features that differentiate it from other vaccines currently in use for the control of Covid 19, both for the mechanism of action – underline the experts – and for the aspects related to conservation and distribution, fundamental for the management of future phases. of the pandemic “. The new vaccine exploits a different platform both from mRna-based shield products and from those with an adenoviral vector. or modified viruses, unable to replicate and cause infection, containing Sars-CoV-2 gene fragments). Both platforms predict that the production of viral proteins (the antigens that trigger the immune response) takes place inside the cells of the vaccinated. The platform used for LeCoVax2 is instead “completely different, because it is based on a modified single-cell microorganism, capable of both producing and transporting the viral proteins that act as antigens and that can therefore stimulate the production of antibodies in the vaccine”. The microorganism used is Leishmania tarentolae, “a non-pathogenic Leishmania for humans, and which has nothing to do with the one that causes leishmaniasis in dogs – the scientists specify – which can be administered in an inactivated form”. It represents “a sort of micro-factory that can be used for the production of proteins very similar to those produced in the cells of a mammal, for example by a virus during infection or by an RNA vaccine – says Epis from the Department of Biosciences of the Milanese State University. – Once inoculated in a mammal, the viral proteins produced in Leishmania have the ability to act like the proteins produced by the virus itself during natural infection, therefore as viral antigens capable of stimulating the production of antibodies “.” Leishmania – highlights Bandi, also from the Department of Biosciences UniMi – has another peculiar characteristic: a marked tendency to penetrate inside the cells that intervene in the early stages of the immune response, the dendritic cells. Therefore, the use of Leishmania as a system for the production and transport of antigens allows these molecules to be conveyed directly to the cells that play a central role in the induction of the immune response. These are the characteristics that prompted us to create LeCoVax2 “.” On paper – says Montomoli of VisMederi – LeCoVax2 was promising from the early stages of development, but only in the last few weeks have we obtained the experimental results that have proved its effectiveness as an inductor of a specific antibody response. The study was carried out on a mouse model and allowed to detect the production of antibodies capable of neutralizing the Sars-CoV-2 virus “.” The peculiarities of LeCoVax2 make it very promising for application in developing countries – comments Zuccotti, dean of the Faculty of Medicine and a member of the Department of Biomedical and Clinical Sciences’ L. Sacco ‘by UniMi – The technology necessary for its production is relatively simple. Furthermore, being administered in an inactivated form, it can be developed into rehydratable lyophilized preparations, therefore easy to store and distribute. Finally, we believe that LeCoVax2 can be developed for mucosal administration (e.g. oral), which would facilitate its use, an important aspect if the anti-Covid vaccination were to be repeated over the years. In the coming weeks we will proceed with the preclinical investigations on LeCoVax2, especially for the definition of the most suitable formulation for use in clinical studies “. The development of LeCoVax2 – reads the note – was made possible thanks to the funding of the Romeo and Enrica Foundation. Invernizzi, which made it possible to set up the homonymous Romeo University pediatric research center in 2016. The research activities were supported by the commitment and contribution of numerous scientists, both of UniMi (including Ilaria Varotto Boccazzi, Louise Gourlay, Paolo Gabrieli, Camilla Recordati, Paolo Fiorina) and from the VisMederi research institute (Alessandro Manenti, Francesca Dapporto), and from the Innovation and Knowledge Enhancement Department.