Identificación de señales de selección natural en genes de Plasmodium vivax que codifican proteínas involucradas en el proceso de invasión para determinar su potencial uso en una vacuna antimalárica

Abstract

Plasmodium vivax, an endoparasite that arose in Asia and spread around the world, has biomedical importance given that it is the second most important human-malaria parasite. Although efforts have been made to reduce the impact of this disease, the social and economic conditions of the most affected places, together with social and political conflicts in several endemic areas, make the parasite control and elimination a laborious task. The emergence of insecticide resistance by the transmitting vector as well as antimalarialresistant parasites worsen the problem. Therefore, new alternatives to allow reducing the incidence of the disease have become a priority. An antimalarial vaccine development against the causal pathogens has been proposed as a cost-effective intervention which would help in controlling malaria. However, the high P. vivax genetic diversity remains as one of the challenges to overcome for the design of a fully effective vaccine. Currently, several potential P. vivax vaccine candidates have been described. Nevertheless, the genetic diversity of a small number of them has been assessed, due to the high amount of time and economic resources required. Additionally, there is a modest knowledge about the real role of these antigens during the invasion process of target cells since maintaining an in vitro culture of this parasite species is particularly difficult. Therefore, new approaches that allow identifying conserved regions by natural selection which are frequently associated with functional importance, might be used as a starting point for the identification or prioritization of new potential vaccine candidates. This work presents a new approach to assess the genetic diversity of potential candidate antigens, determining negatively selected regions that can then be considered for designing a fully effective vaccine. This approach is not limited to P. vivax and could be useful in other microorganisms.