Loss of endothelial protein C receptor (EPCR) occurs at the sites of Plasmodium falciparum-infected erythrocyte sequestration in patients with or who died from cerebral malaria. In children presenting with different clinical syndromes of malaria, we assessed the relationships between endogenous plasma soluble EPCR (sEPCR) levels and clinical presentation or mortality. After adjustment for age, for treatment before admission, and for a known genetic factor, sEPCR level at admission was positively associated with cerebral malaria (P = .011) and with malaria-related mortality (P = .0003). Measuring sEPCR levels at admission could provide an early biological marker of the outcome of cerebral malaria.

Plasmodium falciparum is responsible of severe malaria, including cerebral malaria (CM). During its intra-erythrocytic maturation, parasite-derived proteins are expressed, exported and presented at the infected erythrocyte membrane. To identify new CM-specific parasite membrane proteins, we conducted a mass spectrometry-based proteomic study and compared the protein expression profiles between 9 CM and 10 uncomplicated malaria (UM) samples. Among the 1097 Plasmodium proteins identified, we focused on the 499 membrane-associated and hypothetical proteins for comparative analysis. Filter-based feature selection methods combined with supervised data analysis identified a subset of 29 proteins distinguishing CM and UM samples with high classification accuracy. A hierarchical clustering analysis of these 29 proteins based on the similarity of their expression profiles revealed two clusters of 15 and 14 proteins, respectively under- and over-expressed in CM. Among the over-expressed proteins, the MESA protein is expressed at the erythrocyte membrane, involved in proteins trafficking and in the export of variant surface antigens (VSAs), but without antigenic function. Antigen 332 protein is exported at the erythrocyte, also involved in protein trafficking and in VSAs export, and exposed to the immune system. Our proteomics data demonstrate an association of selected proteins in the pathophysiology of CM.

BackgroundCytoadherence of Plasmodium falciparum-infected erythrocytes (IEs) in deep microvasculature endothelia plays a major role in the pathogenesis of cerebral malaria (CM). This biological process is thought to be mediated by P. falciparum erythrocyte membrane protein-1 (PfEMP-1) and human receptors such as CD36 and ICAM-1. The relationship between the expression of PfEMP-1 variants and cytoadherence phenotype in the pathology of malaria is not well established.MethodsCytoadherence phenotypes of IEs to CD36, ICAM-1, CSPG and the transcription patterns of A, B, var2csa, var3, var gene groups and domain cassettes DC8 and DC13 were assessed in parasites from children with CM and uncomplicated malaria (UM) to determine if cytoadherence is related to a specific transcription profile of pfemp-1 variants.ResultsParasites from CM patients bind significantly more to CD36 than those from UM patients, but no difference was observed in their binding ability to ICAM-1 and CSPG. CM isolates highly transcribed groups A, B, var2csa, var3, DC8 and DC13 compared to UM parasites. The high transcription levels of var genes belonging to group B positively correlated with increased binding level to CD36.ConclusionCM isolates bind significantly more to CD36 than to ICAM-1, which was correlated with high transcription level of group B var genes, supporting their implication in malaria pathogenesis.

BackgroundPlasmodium falciparum exports proteins that remodel the erythrocyte membrane. One such protein, called Pf155/RESA (RESA1) contributes to parasite fitness, optimizing parasite survival during febrile episodes. Resa1 gene is a member of a small family comprising three highly related genes. Preliminary evidence led to a search for clues indicating the involvement of RESA2 protein in the pathophysiology of malaria. In the present study, cDNA sequence of resa2 gene was obtained from two different strains. The proportion of P. falciparum isolates having a non-stop T1526C mutation in resa2 gene was evaluated and the association of this genotype with severity of malaria was investigated.MethodsResa2 cDNAs of two different strains (a patient isolate and K1 culture adapted strain) was obtained by RT-PCR and DNA sequencing was performed to confirm its gene structure. The proportion of isolates having a T1526C mutation was evaluated using a PCR-RFLP methodology on groups of severe malaria and uncomplicated patients recruited in 1991–1994 in Senegal and in 2009 in Benin.ResultsA unique ORF with an internal translation stop was found in the patient isolate (Genbank access number : JN183870), while the K1 strain harboured the T1526C mutation (Genbank access number : JN183869) which affects the internal stop codon and restores a full length coding sequence. About 14% of isolates obtained from Senegal and Benin harboured mutant T1526C parasites. Some isolates had both wild and mutant resa alleles. The analysis excluding those mixed isolates showed that the resa2 T1526C mutation was found more frequently in severe malaria cases than in uncomplicated cases (p = 0.008). The association of the presence of the mutant allele and parasitaemia >4% was shown in multivariate analysis (p = 0.03) in the group of Beninese children.ConclusionsAll T1526C mutant parasites theoretically have the ability to give rise to a full-length RESA2 protein. This study raises the hypothesis that the RESA2 protein could favour high-density infections. Other studies in various geographic settings and probably including more patients are now required to replicate these results and to answer the questions raised by these results.

Setting Drug resistance threatens tuberculosis (TB) control, particularly among HIV-infected persons. Objective We surveyed antiretroviral therapy (ART) programs from lower-income countries on prevention and management of drug-resistant TB. Design We used online questionnaires to collect program-level data in 47 ART programs in Southern Africa (14), East Africa (8), West Africa (7), Central Africa (5), Latin America (7) and Asia-Pacific (6 programs) in 2012. Patient-level data were collected on 1,002 adult TB patients seen at 40 of the participating ART programs. Results Phenotypic drug susceptibility testing was available at 36 (77%) ART programs, but only used for 22% of all TB patients. Molecular drug resistance testing was available at 33 (70%) programs and used for 23% of all TB patients. Twenty ART programs (43%) provided directly observed therapy (DOT) during the whole treatment, 16 (34%) during intensive phase only and 11 (23%) did not follow DOT. Fourteen (30%) ART programs reported no access to second-line TB regimens; 18 (38%) reported TB drug shortages. Conclusions Capacity to diagnose and treat drug-resistant TB was limited across ART programs in lower income countries. DOT was not always implemented and drug supply was regularly interrupted, which may contribute to the global emergence of drug resistance.