RIFINs are adhesins implicated in severe Plasmodium falciparum malaria

Abstract

Rosetting is a virulent Plasmodium falciparum phenomenon associated with severe malaria. Here we demonstrate that P. falciparum-encoded repetitive interspersed families of polypeptides (RIFINs) are expressed on the surface of infected red blood cells (iRBCs), where they bind to RBCs--preferentially of blood group A--to form large rosettes and mediate microvascular binding of iRBCs. We suggest that RIFINs have a fundamental role in the development of severe malaria and thereby contribute to the varying global distribution of ABO blood groups in the human population.

Plasmodium Malaria and ABO Blood Group among Blood Donors in Yenegoa, Bayelsa State, Nigeria

“…It has long been known that people with blood type O are protected from dying of severe malaria and that blood group O provides protection against severe malaria and that may explains why blood type O seems to be the commonest blood type in malaria endemic countries and in the present study [38]. Goel et al reported that because of endemicity of malaria in Nigeria, more than half of the population belongs to blood group O which protects against malaria [39]. That again may buttress the finding in this study where Blood group O has the highest prevalence of infection.…”

Critical Steps in Protein Export of Plasmodium falciparum Blood Stages

“…The next important goal is the functional characterisation of these proteins (see Outstanding Questions Box), which has so far predominantly yielded data on functions in host cell rigidity and PfEMP1 transport and display [77,78,[95][96][97][98][99]. There are likely to be many other functions of exported proteins that have so far remained obscure, such as the recently discovered functions in intercellular communication [90,91] and lipid biology [100], or for which the molecular basis was previously unknown, such as in the rosetting of infected red blood cells [101].…”

Plasmodium falciparum complicated malaria: Modulation and connectivity between exportome and variant surface antigen gene families

“…Over expression of type A rifins in PFC isolates suggests enhancement of mechanisms affecting immune evasion on part of the parasite infected RBCs. Additionally, very recently, it has been reported that A-rifins can bind to RBCs preferentially with blood group A antigen to form large rosettes and may play a central role in pathogenesis of severe P. falciparum malaria (Goel et al, 2015). The var group genes encoding PfEMP1 are known to show mutually exclusive patterns of expression unlike rifins (Petter et al, 2007).…”