Inhibition of Plasmodium knowlesi merozoite invasion into human erythrocytes by antibodies raised against the parasite's secreted protein with altered thrombospondin repeat (SPATR)
Document Type
Article
Publication Date
6-1-2024
Abstract
The Plasmodium secreted protein with an altered thrombospondin repeat (SPATR) has been known to play an important role in the malaria parasite's invasion into host erythrocytes. This protein is immunogenic and has been considered as one of the potential vaccine candidates against malaria parasite infection. Thus far, only a handful immunological studies have been carried out on P. knowlesi SPATR (PkSPATR), and none of these studies investigated the immunoprotective properties of the protein. In the present study, the ability of anti-PkSPATR antibodies to inhibit invasion of human erythrocytes was assessed in an in vitro merozoite invasion inhibition assay. The antibodies were harvested from the serum of a rabbit which was immunised with recombinat PkSPATR. Results from the merozoite invasion inhibition assay revealed significant antibody invasion inhibitory activity in a concentration dependent manner (concentration range: 0.375 - 3.00 mg/ml) with inhibition rate ranging from 20% to 32%. Future studies, such as anti-PkSPATR antibodies inhibitory effect on sporozoite invasion of human liver cells, need to be carried out to assess the potential of PkSPATR as a knowlesi malaria vaccine candidate.
Keywords
Plasmodium knowlesi, SPATR, antibody, merozoite invasion inhibition assay
Divisions
Parasit
Funders
Long Term Research Grant Scheme (LRGS) of the Ministry of Higher Education Malaysia (LRGS/1/2018/UM/01/1/1)
Publication Title
Tropical Biomedicine
Volume
41
Issue
2
Publisher
Malaysian Society of Parasitology and Tropical Medicine
Publisher Location
21-5-2, BLOCK, E, DIAMOND SQUARE, JALAN 3-50, OFF JALAN GOMBAK, KUALA LUMPUR, MALAYSIA