Publications

plasmodium falciparum malaria in the low transmission peruvian amazon is associated with immunologic memory.	the development of clinical immunity to plasmodium falciparum malaria is thought to require years of parasite exposure, a delay often attributed to difficulties in developing protective antibody levels. in this study we evaluated several p. falciparum vaccine-candidate antigens, including apical membrane antigen-1 (ama-1), circumsporozoite protein (csp), erythrocyte binding antigen (eba-175), and the 19kd region of merozoite surface protein-1 (msp1(19)). after observing a more robust antibody re ...	2012	22252876
biosynthesis, localisation and macromolecular arrangement of the plasmodium falciparum translocon of exported proteins; ptex.	a major virulence determinant in the protozoan parasite plasmodium falciparum is a protein complex known as ptex (plasmodium translocon of exported proteins). ptex is a putative protein trafficking machinary responsible for the export of hundreds of proteins across the parasitophorous vacuole membrane and into the human host cell. five proteins are known to comprise the ptex complex and in this study, three of the major stoichiometric components are investigated including; hsp101 (a aaa+ atpase) ...	2012	22253438
changes related to age in natural and acquired systemic self-igg responses in malaria.	background. absence of acquired protective immunity in endemic areas children leads to higher susceptibility to severe malaria. to investigate the involvement of regulatory process related to self-reactivity, we evaluated potent changes in auto-antibody reactivity profiles in children and older subjects living in malaria-endemic zones comparatively to none-exposed healthy controls. methods. analysis of igg self-reactive footprints was performed using western blotting against healthy brain antige ...	2011	22253622
targeting sialic acid dependent and independent pathways of invasion in plasmodium falciparum.	the pathology of malaria is a consequence of the parasitaemia which develops through the cyclical asexual replication of parasites in a patient's red blood cells. multiple parasite ligand-erythrocyte receptor interactions must occur for successful plasmodium invasion of the human red cell. two major malaria ligand families have been implicated in these variable ligand-receptor interactions used by plasmodium falciparum to invade human red cells: the micronemal proteins from the erythrocyte bindi ...	2012	22253925
plate-based transfection and culturing technique for genetic manipulation of plasmodium falciparum.	abstract: genetic manipulation of malaria parasites remains an inefficient, time-consuming and resource-intensive process. presented here is a set of methods for 96-well plate-based transfection and culture that improve the efficiency of genetic manipulation of plasmodium falciparum. compared to standard protocols plate-based transfection requires 20-fold less dna, transient transfection efficiency achieved is approximately seven-fold higher, whilst stable transfection success rate is above 90%. ...	2012	22257490
identification of optimal epitopes for plasmodium falciparum rapid diagnostic tests that target histidine-rich proteins 2 and 3.	rapid diagnostic tests (rdts) represent important tools to diagnose malaria infection. to improve understanding of the variable performance of rdts that detect the major target in plasmodium falciparum, namely histidine rich protein 2 (hrp2), and to inform the design of better tests we undertook detailed mapping of the epitopes recognized by eight hrp-specific monoclonal antibodies (mabs). to investigate for geographic skewing of this polymorphic protein we analysed the distribution of these epi ...	2012	22259210
effect of quinine therapy on plasma glucose and plasma insulin levels in pregnant women infected with plasmodium falciparum malaria in gezira state.	to determine if quinine has a metabolic effect during treatment of severe or complicated malaria, we studied its effects on plasma glucose and plasma insulin levels in 150 pregnant women with malaria referred to madani maternity teaching hospital, gezira state and 50 healthy pregnant controls. levels were determined at baseline (day 0) before the start of quinine treatment, after 2 days of treatment (2 hours after the 4th dose) and after 7 days of treatment (day 8). there was a statistically sig ...	2011	22259921
plasmodium falciparum histones induce endothelial proinflammatory response and barrier dysfunction.	plasmodium falciparum is a protozoan parasite of human erythrocytes that causes the most severe form of malaria. severe p. falciparum infection is associated with endothelial activation and permeability, which are important determinants of the outcome of the infection. how endothelial cells become activated is not fully understood, particularly with regard to the effects of parasite subcomponents. we demonstrated that p. falciparum histones extracted from merozoites (heh) directly stimulated the ...	2012	22260922
plasmodium-helminth coinfection and its sources of heterogeneity across east africa.	background. plasmodium-helminth coinfection can have a number of consequences for infected hosts, yet our knowledge of the epidemiology of coinfection across multiple settings is limited. this study investigates the distribution and heterogeneity of coinfection with plasmodium falciparum and 3 major helminth species across east africa.methods. cross-sectional parasite surveys were conducted among 28 050 children in 299 schools across a range of environmental settings in kenya, uganda, and ethiop ...	2012	22262792
pfset10, a plasmodium falciparum methyltransferase, maintains the active var gene in a poised state during parasite division.	a major virulence factor of the malaria parasite plasmodium falciparum is erythrocyte membrane protein 1 (pfemp1), a variant protein expressed on the infected erythrocyte surface. pfemp1 is responsible for adherence of infected erythrocytes to the endothelium and plays an important role in pathogenesis. mutually exclusive transcription and switched expression of one of 60 var genes encoding pfemp1 in each parasite genome provides a mechanism for antigenic variation. we report the identification ...	2012	22264509
electroporation-mediated genetic vaccination for antigen mapping: application to plasmodium falciparum var2csa protein.	genetic vaccination, consisting in delivering a genetically engineered plasmid dna by a non-viral vector or technique into a tissue, is currently of great interest. new delivery technique including dna transfer by electroporation recently greatly improved the potency of this concept. because it avoids the step of producing a recombinant protein, it is particularly of use in studying the immunogenic properties of large proteins. here we describe the use of electroporation mediated dna immunizatio ...	2011	22265101
fcγriia polymorphism and anti-malaria specific igg and igg subclass responsese in populations differing in susceptibility to malaria in burkina faso.	fcγriia is known to be polymorphic; and certain variants err associated with differt susceptibilities to malaria. studies involving the fulani ethnic group reported an ethnic difference in fcγriia-r131h genotype frequencies between the fulani and other sympatric groups. no previous studies have addressed these questions in burkina faso. the present study aimed to assess the influence of fcγriia-r131h polymorphism on anti- falciparum malaria igg and igg subclass responses in the fulani and the mo ...	2012	22268665
futile attempts to differentiate provide molecular evidence for individual differences within a population of cells during cellular reprogramming.	the heterogeneity of cell populations and the influence of stochastic noise might be important issues for the molecular analysis of cellular reprogramming at the systems level. here, we show that in physarum polycephalum, the expression patterns of marker genes correlate with the fate decision of individual multinucleate plasmodial cells that had been exposed to a differentiation-inducing photo-stimulus. for several hours after stimulation, the expression kinetics of pi-3-kinase, piwi, and pumil ...	2012	22269001
ensemble modeling of the likely public health impact of a pre-erythrocytic malaria vaccine.	the rts,s malaria vaccine may soon be licensed. models of impact of such vaccines have mainly considered deployment via the world health organization's expanded programme on immunization (epi) in areas of stable endemic transmission of plasmodium falciparum, and have been calibrated for such settings. their applicability to low transmission settings is unclear. evaluations of the efficiency of different deployment strategies in diverse settings should consider uncertainties in model structure.	2012	22272189
anti-il-2 treatment impairs the expansion of t(reg) cell population during acute malaria and enhances the th1 cell response at the chronic disease.	plasmodium chabaudi infection induces a rapid and intense splenic cd4(+) t cell response that contributes to both disease pathogenesis and the control of acute parasitemia. the subsequent development of clinical immunity to disease occurs concomitantly with the persistence of low levels of chronic parasitemia. the suppressive activity of regulatory t (t(reg)) cells has been implicated in both development of clinical immunity and parasite persistence. to evaluate whether il-2 is required to induc ...	2012	22272258
t-cell responses to the dblα-tag, a short semi-conserved region of the plasmodium falciparum membrane erythrocyte protein 1.	the plasmodium falciparum erythrocyte membrane protein 1 (pfemp1) is a variant surface antigen expressed on mature forms of infected erythrocytes. it is considered an important target of naturally acquired immunity. despite its extreme sequence heterogeneity, variants of pfemp1 can be stratified into distinct groups. group a pfemp1 have been independently associated with low host immunity and severe disease in several studies and are now of potential interest as vaccine candidates. although anti ...	2012	22272280
clinical assessment of a recombinant simian adenovirus chad63: a potent new vaccine vector.	background. vaccine development in human plasmodium falciparum malaria has been hampered by the exceptionally high levels of cd8(+) t cells required for efficacy. use of potently immunogenic human adenoviruses as vaccine vectors could overcome this problem, but these are limited by preexisting immunity to human adenoviruses.methods. from 2007 to 2010, we undertook a phase i dose and route finding study of a new malaria vaccine, a replication-incompetent chimpanzee adenovirus 63 (chad63) encoding ...	2012	22275401
sexual development in plasmodium: lessons from functional analyses.		2012	22275863