Phylogenetic analysis of circumsporozoite protein (csp) variants from Plasmodium vivax in blood samples from the brazilian Amazon region

Vivax malaria, caused by Plasmodium vivax (Pv), is responsible for generating debilitating effects that socially and economically affect tropical and sub-tropical regions. It is estimated that approximately 2.85 billion people may become infected in these regions. In its infective form, Plasmodium expresses the circumsporozoite protein (CSP) in its membrane, which is immunogenic and helps the protozoan to invade human hepatocytes. Several studies use this protein for the development of recombinant vaccines, however, with the appearance of polymorphisms in CSP genes, this approach has been reevaluated. Together with sequences recovered from the Gene bank of isolates from several endemic areas around the world, the distribution of incompatibility of the central repeat region of the gene, the estimation of genotype frequencies and phylogenetic analysis of the 3′ terminal region will be analyzed, to to obtain an overview of the genetic relationships between regional and world isolates. Still, we will determine the levels of antibodies against the peptides of the VK210, VK247 and P.vivax-like variants using the ELISA method. A total of N=200 samples representing the Eastern and Central Amazon, state of Pará, from the municipalities of Novo Repartimento (n=75), Belém (n=25) and Goiansésia do Pará (n=100) will be used in this study. It is hoped that the results obtained will show the variability of genotypes in Brazilian isolates and offer information on the genetic diversity of the parasite populations in the national territory, offering new subsidies for possible treatments, diagnosis and development of vaccines.

Project details

Enabling Technologies & Assays
P. vivax
Parasite Genetic Diversity

May 2023

Brazil