Characterising PvRBSA: an exclusive protein from Plasmodium species infecting reticulocytes
Darwin A Moreno-Pérez1,2, Luis A Baquero1, Diana M Chitiva-Ardila1
1Molecular Biology and Immunology Department, Fundación Instituto de Inmunología de Colombia (FIDIC), Carrera 50 No. 26-20, Bogotá, D.C., Colombia.
Background:
Plasmodium vivax uses multiple ligand-receptor interactions for preferential invasion of human reticulocytes. Several of these ligands have been identified by in silico approaches based on the role displayed by their orthologs in other Plasmodium species during initial adhesion or invasion. However, the cell adhesion role of proteins that are exclusive to species that specifically invade reticulocytes (as P. vivax and P. cynomolgi) has not been evaluated to date. This study aimed to characterise an antigen shared between Plasmodium species that preferentially infect reticulocytes with a focus on assessing its binding activity to target cells.
Results:
An in silico analysis was performed using P. vivax proteome data to identify and characterise one antigen shared between P. vivax and P. cynomolgi. This led to identification of the pvrbsa gene present in the P. vivax VCG-I strain genome. This gene is transcribed in mature schizonts and encodes a protein located on the parasite surface. rPvRBSA was antigenic and capable of binding to a population of reticulocytes with a different Duffy phenotype. Interestingly, the molecule showed a higher percentage of binding to immature human reticulocytes (CD71hi).
Conclusions:
This study describes for the first time, a molecule involved in host cell binding that is exclusive in reticulocyte-infecting Plasmodium species. This suggest that PvRBSA is an antigenic adhesin that plays a role in parasite binding to target cells.
Insights
Plasmodium vivax uses a novel surface protein, PvRBSA, to bind reticulocytes. This antigenic adhesin, exclusive to reticulocyte-invading Plasmodium species, shows preferential binding to immature human red blood cells.
Area of Science:
- Malariology
- Parasitology
- Molecular Biology
Background:
- Plasmodium vivax preferentially invades human reticulocytes via multiple ligand-receptor interactions.
- Previous ligand identification relied on orthologs from other Plasmodium species.
- The cell adhesion role of proteins exclusive to reticulocyte-invading Plasmodium species remains largely uncharacterized.
Purpose of the Study:
- To characterize a Plasmodium antigen shared between reticulocyte-infecting species.
- To assess the binding activity of this antigen to target host cells.
Main Methods:
- In silico analysis of the Plasmodium vivax proteome.
- Identification and characterization of the pvrbsa gene.
- Assessment of the encoded protein's antigenicity and binding capabilities.
Main Results:
- The pvrbsa gene was identified in the P. vivax VCG-I strain, transcribed in schizonts, and encodes a surface protein (rPvRBSA).
- rPvRBSA demonstrated antigenicity and bound to reticulocytes with varying Duffy phenotypes.
- A higher binding percentage was observed for immature human reticulocytes (CD71hi).
Conclusions:
- PvRBSA is described as a novel molecule involved in host cell binding, exclusive to reticulocyte-infecting Plasmodium species.
- PvRBSA is proposed to be an antigenic adhesin playing a role in parasite binding to target cells.
More Related Videos
10:22Methods to Investigate the Regulatory Role of Small RNAs and Ribosomal Occupancy of Plasmodium falciparum
Published on: December 4, 2015
07:27A Simple Protocol for Platelet-mediated Clumping of Plasmodium falciparum-infected Erythrocytes in a Resource Poor Setting
Published on: May 16, 2013