Identification of protein markers in patients infected with Plasmodium knowlesi, Plasmodium falciparum and Plasmodium vivax.
Malaria is caused by parasitic protozoans of the genus Plasmodium and is one of the most prevalent infectious diseases in tropical and subtropical regions. For this reason, effective and practical diagnostic methods are urgently needed to control the spread of malaria. The aim of the current study was to identify a panel of new malarial markers, which could be used to diagnose patients infected with various Plasmodium species, including P. knowlesi, P. vivax and P. falciparum. Sera from malaria-infected patients were pooled and compared to control sera obtained from healthy individuals using the isobaric tags for relative and absolute quantitation (iTRAQ) technique. Mass spectrometry was used to identify serum proteins and quantify their relative abundance. We found that the levels of several proteins were increased in pooled serum from infected patients, including cell adhesion molecule-4 and C-reactive protein. In contrast, the serum concentration of haptoglobin was reduced in malaria-infected individuals, which we verified by western blot assay. Therefore, these proteins might represent infectious markers of malaria, which could be used to develop novel diagnostic tools for detecting P. knowlesi, P. vivax and P. falciparum. However, these potential malarial markers will need to be validated in a larger population of infected individuals.
Department of Oral Biology and Biomedical Sciences, Faculty of Dentistry, University of Malaya, Kuala Lumpur 50603, Malaysia. alanmukangwai@yahoo.com.
Alan Kang-Wai
AK
Mu
Department of Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia. pcbee@um.edu.my.
Ping Chong
PC
Bee
Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia. lauyeeling@um.edu.my.
Yee Ling
YL
Lau
Department of Oral Biology and Biomedical Sciences, Faculty of Dentistry, University of Malaya, Kuala Lumpur 50603, Malaysia. chenyeng@um.edu.my.
Yeng
Y
Chen
D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein / Q000032:analysis* / Q000378:metabolism; D015815:Cell Adhesion Molecules / Q000097:blood* / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D015536:Down-Regulation; D006242:Haptoglobins / Q000032:analysis* / Q000378:metabolism; D006801:Humans; D007136:Immunoglobulins / Q000097:blood* / Q000378:metabolism; D008288:Malaria / Q000175:diagnosis* / Q000469:parasitology; D010361:Patients; D010455:Peptides / Q000378:metabolism; D010963:Plasmodium falciparum / Q000302:isolation & purification; D016790:Plasmodium knowlesi / Q000302:isolation & purification; D010966:Plasmodium vivax / Q000302:isolation & purification; D053719:Tandem Mass Spectrometry
D015415:Biomarkers; C498601:CADM4 protein, human; D015815:Cell Adhesion Molecules; D006242:Haptoglobins; D007136:Immunoglobulins; D010455:Peptides; D002097:C-Reactive Protein