- Authors: Cabral FJ, Carlos BC, Martha RD, Medeiros MM, Silva LHPD, Silva NM, Stabeli RG, Vianna LG, Wunderlich G
- Publication Year: 2017
- Journal: Memórias do Instituto Oswaldo Cruz
Plasmodium falciparum
The surface of infected red blood cells (iRBCs) has been widely investigated because of the molecular complexity and pathogenesis mechanisms involved. Asymptomatic individuals are important in the field. They can perpetuate transmission as natural reservoirs. However, this presents a challenge for diagnosing malaria because of their low levels of circulating parasites. Recent studies of iRBC antibody recognition have shown that responses are quantitatively similar in symptomatic and asymptomatic infections. Although no studies have characterised the plasmodial proteins targeted by this response.
The researchers objective was to identify Plasmodium falciparum proteins associated with iRBC ghosts recognised by antibodies in the sera of symptomatic and asymptomatic individuals in the Brazilian Amazon.
They collected symptomatic and asymptomatic sera from patients residing in the Brazilian Amazon and P. falciparum iRBC ghosts to identify the proteins involved in natural antibody recognition by 2D-electrophoresis, western blotting, and high- resolution mass spectrometry.
2D gel-based immunoproteome analysis using symptomatic and asymptomatic sera identified 11 proteins with at least one unique peptide, such as chaperones HSP70-1 and HSP70-x. which likely are components of the secretion machinery/PTEX translocon. PfEMP1 is involved in antigenic variation in symptomatic infections and we found putative membrane proteins whose functions are unknown.
Our results suggest a potential role of old and new proteins, such as antigenic variation proteins, iRBC remodelling, and membrane proteins, with no assigned functions related to the immune response against P. falciparum, providing insights into the pathogenesis, erythrocyte remodelling, and secretion machinery important for alternative diagnosis and/or malaria therapy.