A malária asociada à gavidez pode gerar complicações para a mãe e para o feto. Receptores do tipo Toll (TLR) TLR2, TLR4 e TLR9, podem reconhecer componentes do Plasmódio. Estes receptores sinalizam via proteína MyD88. Contudo existem poucos dados sobre os TLR na malária placentária. Assim, o objetivo desse trabalho foi estudar o papel dos TLR2, 4, 9 e da MyD88 na malária placentária. Dentre fêmeas C57BL/6, TLR2-/-, TLR9-/- e MyD88-/-, a linhagem MyD88-/- apresentou maiores níveis de parasitemia, sobrevivência e cuidado parental, e ainda placentas de fêmeas MyD88-/- infectadas, ao contrario das TLR2-/- e TLR9-/-, não tiveram diminuição do espaço vascular em relação aos controles. Animais C57BL/6 infectados apresentaram aumento do mRNA de IL1-<font face=\"Symbol\">b e IL-6 na placenta, o que não ocorreu nos MyD88-/-. Gestantes C57BL/6 e MyD88-/- infectadas tiveram mais esplenócitos, com expansão preferencial de linfócitos B (CD19+). Também foi evidenciado nos animais C57BL/6 infectados um aumento da expressão do marcador de ativação CD69 nos linfócitos TCD8+. Em conjunto, estes resultados sugerem que a sinalização via MyD88 é importante para o desenvolvimento da malária placentaria e esta pode estar relacionada com a resposta inflamatória exacerbada induzida pelo parasita. / Pregnancy associated malaria can lead to complications both for the mother and the fetus. Toll like receptors (TLR) TLR2, TLR4 and TLR9 can recognize components of the Plasmodium sp. These receptors signal through the MyD88 protein. However there are few data on TLR in placental malaria. Thus, The objective of this work was to study the role of TLR2, 4, 9 and MyD88 in placental malaria. Among female mice C57BL/6, TLR2-/-, TLR9-/- and MyD88-/-, the lineage MyD88-/- showed higher levels of parasitemia, survival and parental care, and still placentas of MyD88-/- infected female, differently of TLR2-/- and TLR9-/-, had no decrease in the vascular space compared to controls. Animals C57BL/6 infected showed increased mRNA for IL1-<font face=\"Symbol\">b and IL-6 in the placenta, which did not occur in MyD88-/-. Pregnant infected C57BL/6 and MyD88-/- had more splenocytes, with preferential expansion of B lymphocytes (CD19+). in infected C57BL/6 was also demonstrated an increased expression of the activation marker CD69 on CD8+ T lymphocytes. Together, these results suggest that signaling through MyD88 is important for the development of placental malaria and this may be related with an increased inflammatory response induced by the parasite.

Made available in DSpace on 2016-08-10T10:54:14Z (GMT). No. of bitstreams: 1 ANNY CHRISTIANN GARCIA GRANZOTO.pdf: 1984565 bytes, checksum: be4a4f1b4178ba3a073c0076dc2efbcd (MD5) Previous issue date: 2014-03-21 / This study aimed to evaluate the factors that might influence the occurrence of malaria in the municipality of Sinop, in the State of Mato Grosso, between 2003 and 2012. A descriptive, explanatory epidemiological study was performed and the research procedure was indirect documental for the cases of malaria reported in the System of Information of Epidemiological Vigilance Malaria (SIVEP-Malaria). From the 2,435 positive cases, 1,950 cases were autochthonous (80.08%). Despite the fact that there were no differences between sexes, males represented 64.80% in the age group between 19 and 39 years old (59.72%). In this study 94% of the cases were related to Plasmodium vivax. The urbanization process was not proportional to the number of cases and the incidence of malaria did not correlate to seasonality. The municipality presented the Annual Parasitary Index (IPA) lower than 9.9% which classifies it as an area of low risk for malaria transmission. At the beginning of this study the cases were concentrated in settlements and now it presents as an urban character impelled y recent deforestation favored by the urban area growth. The districts with higher incidence were Jardim Primaveras, Palmeiras, Violetas and the downtown area. In conclusion there is a tendency in the incidence of the autochthonous cases of malaria in Sinop and the necessity to stimulate the municipal management to concentrate the actions towards the vigilance of autochthonous cases for this municipality as well as to prioritize policies that involve preventive actions as basic health sanitation and social action. / O presente estudo teve como objetivo avaliar os fatores que podem influenciar a casuística da malária no município de Sinop, no Estado de Mato Grosso, entre 2003 e 2012. Foi realizado um estudo epidemiológico, descritivo, explicativo e a técnica da pesquisa foi documental indireta para os casos de malária registrados no Sistema de Informação de Vigilância Epidemiológica Malária (SIVEP-Malária). Dos 2.435 casos positivos, 1.950 casos foram autóctones (80,08%). Embora não tenha havido uma diferença significativa entre os sexos, o masculino apresentou 64,80%, na faixa etária entre 19 a 39 anos (59,72%). No estudo, 94% dos casos foram relacionados com Plasmodium vivax. O processo de urbanização não foi proporcional ao número de casos e a incidência de malária não apresentou relação quanto à sazonalidade. O município apresentou Índice Parasitário Anual (IPA) menor que 9,9%, que o classifica como área de baixo risco para a transmissão da malária. No período de início da pesquisa, os casos concentravam-se em assentamentos e atualmente apresenta um caráter urbano impulsionado pelo desmatamento recente, favorecido pelo crescimento da área urbana. Os bairros com maior incidência foram o Jardim Primaveras, Palmeiras, Violetas e o centro da cidade. Concluiu-se a existência de uma tendência na incidência dos casos autóctones de malária em Sinop e a necessidade de estimular os gestores municipais a concentrarem as ações para a vigilância dos casos autóctones para este município bem como, priorizar políticas que envolvam ações preventivas, como saneamento básico de saúde e de ação social.

O Antígeno 1 de Membrana Apical (AMA-1) tem sido sugerido como candidato a compor uma vacina contra estágios assexuados sanguíneos de Plasmodium. Recentemente nosso grupo identificou o domínio II (DII) de AMA-1 de Plasmodium vivax (PvAMA-1) como uma região altamente reconhecida por anticorpos IgG de indivíduos brasileiros infectados por P. vivax. No presente estudo avaliamos as propriedades imunogênicas da proteína recombinante DII, produzida a partir de Escherichia coli. Grupos de 6 camundongos fêmeas BALB/c foram imunizados quatro vezes com 10 &#181;g dessa proteína na presença de diferentes formulações de adjuvantes [Adjuvante Completo/Incompleto de Freund (ACF/AIF), MPL-TDM, TiterMax, Hidróxido de Alumínio (Alum), Quil A, QS-21 e CpG-ODN 1826], individualmente, ou em combinação (Alum + QS-21 ou Alum + CpG-ODN 1826)). Nosso objetivo foi avaliar comparativamente a resposta de anticorpos (IgM, IgG e isotipos de IgG), induzida pelos diferentes esquemas de imunizações, visando futuros estudos pré-clínicos em primatas não humanos. Os títulos de anticorpos IgG contra (o ectodomínio) PvAMA-1 foram determinados por ELISA, duas semanas após cada imunização. A presença de IgM e dos isotipos de IgG também foi avaliada após o final do esquema de imunizações. Nossos resultados demonstraram que a proteína recombinante DII foi altamente imunogênica em camundongos BALB/c quando administrada na presença dos adjuvantes testados. Altos títulos de IgG1, IgG2a e IgG2b foram observados na maioria dos grupos (com exceção do adjuvante Alum), sugerindo uma resposta mista Th1/Th2. Finalmente, demonstramos que anticorpos monoclonais e policlonais anti-DII reconheceram a proteína nativa expressa na superfície de merozoítas de P. vivax, por imunofluorescência. Em conclusão, nossos resultados mostraram que a proteína recombinante o domínio II de PvAMA-1 (DII) foi imunogênico em camundongos BALB/c quando administrado na presença das diferentes formulações de adjuvantes testadas, sugerindo que esse antígeno possa ser utilizado como uma vacina de subunidade contra a malária vivax. / The Apical Membrane Antigen 1 (AMA-1) has been considered a malaria vaccine candidate against asexual blood stages of Plasmodium. Recently, we identified the domain II (DII) of Plasmodium vivax AMA-1 (PvAMA-1) as a region highly recognized by IgG antibodies from Brazilian individuals infected by P. vivax. In the present study, we evaluated the immunogenic properties of a bacterial recombinant PvAMA-1 DII. Groups of 6 female BALB/c were immunized four times with 10 &#181;g of recombinant protein in the presence of different adjuvant formulations [Complete/Incomplete Freunds Adjuvant (CFA/IFA), MPL-TDM, TiterMax, Aluminum hydroxide (Alum), Quil A, QS-21, CpG-ODN 1826] separately or in combination (Alum + QS-21 or Alum + CpG-ODN 1826). Our goal was to compare the antibody response (IgM, IgG and IgG subclass) induced by different protocols of immunization aiming at future pre-clinical studies in non-human primates. The IgG antibody titers against PvAMA-1 were determined by ELISA two weeks after each immunizing dose. The presence of IgM and IgG subclass were evaluated after the end of immunizations schedule. We found that the recombinant DII was highly immunogenic in BALB/c mice when administered in the presence of all adjuvant tested. High titers of IgG1, IgG2a and IgG2b were observed in all groups (except for Alum adjuvant), suggesting a mixed Th1/Th2 response. Finally, we demonstrated that monoclonal and polyclonal antibodies against DII recognized the native protein expressed on the P. vivax merozoite surface parasites by immunofluorescence. Together, our data demonstrated that the recombinant PvAMA-1(DII) was immunogenic in mice when administered in different adjuvant formulations, suggesting that this protein can be used as part of a sub-unit vaccine against malaria vivax.

The body of work presented here seeks to illuminate the complex relationship between human society, development, and environment for the case of malaria. While malaria profoundly affects human society and prospects for prosperity, public health measures and anthropogenic environmental change alter the intensity of transmission differentially around the globe. Using global maps of malaria risk, the first chapter finds that the elimination of the disease during the course of the 20th century occurred in places where the strength of transmission was weaker due to suboptimal ecology, and that this result holds even after controlling for income levels. The next chapter employs GIS datasets on population, urbanization, malaria risk, and malaria endemicity to spatially estimate the cost of fully deploying ecology-appropriate anti-malaria interventions in Africa; the cost of curbing malaria is found to be small (around $4 per person at risk per year), especially given its high disease burden and subsequent social and economic costs. I next construct a spatial month-to-month ecological index of malaria transmission strength, and use a climate change model to predict changes in ecological transmission strength of malaria and estimate the implied changes in incidence and mortality given current technology and public health efforts. The final chapter uses the malaria ecology index as an instrumental variable to estimate the effect of child mortality on fertility behavior. The large effect of child mortality indicates that malaria has an indirect effect on society beyond morbidity and mortality: high malaria burdens increase fertility rates, thus slowing the demographic transition. These chapters span the fields of epidemiology, public health systems, climate science, economics and demography in order to holistically model the relationship between malaria and human systems; such understanding of coupled human-natural systems will be vital to policy making for sustainable development.

Chan Wan Lui Wendy. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 158-162). / Abstracts in English and Chinese. / Acknowledgements --- p.iii / Abstract --- p.v / List of Abbreviations --- p.ix / List of Figures --- p.xii / List of Tables --- p.xvi / Table of Contents --- p.xvii / Chapter Chapter 1 --- General Introduction --- p.1 / Chapter Chapter 2 --- Literature review --- p.3 / Chapter 2.1 --- Malaria --- p.3 / Chapter 2.2 --- History of malaria --- p.4 / Chapter 2.3 --- Malaria parasites --- p.4 / Chapter 2.4 --- Life cycle --- p.5 / Chapter 2.5 --- Potential use of malaria vaccine --- p.6 / Chapter 2.6 --- Merozoite surface protein 1 (MSP1) --- p.7 / Chapter 2.7 --- Potential use of MSPl --- p.8 / Chapter 2.8 --- Significance of MSPl C-terminal fragments --- p.9 / Chapter 2.8.1 --- Significance of MSP142 --- p.9 / Chapter 2.8.2 --- Significance of MSP119 --- p.11 / Chapter 2.9 --- Production of MSPl C-terminal fragments --- p.12 / Chapter 2.10 --- Plants as bioreactors --- p.12 / Chapter 2.11 --- Expression of MSPl C-terminal fragments in transgenic plants --- p.14 / Chapter 2.12 --- Phaseolin and its sorting signal --- p.19 / Chapter 2.13 --- Protein targeting signals --- p.20 / Chapter Chapter 3 --- Material and methods --- p.23 / Chapter 3.1 --- Introduction --- p.23 / Chapter 3.2 --- Chemical and enzymes --- p.23 / Chapter 3.3 --- Cloning --- p.24 / Chapter 3.3.1 --- MSP142 and MSP119 constructs --- p.24 / Chapter 3.3.2 --- Protein targeting fusion constructs --- p.24 / Chapter 3.3.3 --- GUS fusion Constructs --- p.30 / Chapter (a) --- Particle bombardment --- p.30 / Chapter (b) --- GUS fusion constructs for plant transformation --- p.32 / Chapter (c) --- Modified GUS fusion constructs --- p.38 / Chapter 3.4 --- Cloning of chimeric gene into Agrobacterium binary vector --- p.39 / Chapter 3.4.1 --- Cloning of pSUNl --- p.40 / Chapter 3.4.2 --- Primer sequence --- p.45 / Chapter 3.5 --- Bacterial strains --- p.46 / Chapter 3.6 --- Particle bombardment --- p.46 / Chapter 3.6.1 --- Plant materials --- p.46 / Chapter 3.6.2 --- Microcarrier preparation and coating DNA onto microcarrier --- p.46 / Chapter 3.6.3 --- GUS assay --- p.48 / Chapter 3.7 --- Transgenic expression in Arabidopsis thaliana --- p.49 / Chapter 3.7.1 --- Plant materials --- p.49 / Chapter 3.7.2 --- Agrobacterium transformation --- p.49 / Chapter 3.7.3 --- Vacuum infiltration Arabidopsis transformation --- p.49 / Chapter 3.7.4 --- Selection of successful transformants --- p.50 / Chapter 3.7.5 --- Selection for homozygous plants --- p.51 / Chapter 3.8 --- Transgenic expression in tobacco --- p.51 / Chapter 3.8.1 --- Plant materials --- p.51 / Chapter 3.8.2 --- Agrobacterium transformation --- p.52 / Chapter 3.8.2.1 --- Preparation of Agrobacterium tumefaciens LBA4401 competent cells --- p.52 / Chapter 3.8.3 --- Leaf discs method for tobacco transformation --- p.53 / Chapter 3.8.4 --- GUS staining --- p.54 / Chapter 3.9 --- DNA analysis --- p.55 / Chapter 3.9.1 --- Genomic DNA extraction --- p.55 / Chapter 3.9.2 --- Genomic PCR --- p.55 / Chapter 3.9.3 --- Southern blot --- p.55 / Chapter 3.10 --- RNA analysis --- p.56 / Chapter 3.10.1 --- RNA extraction --- p.56 / Chapter 3.10.2 --- Northern blot --- p.56 / Chapter 3.11 --- Protein analysis --- p.57 / Chapter 3.11.1 --- Protein extraction --- p.57 / Chapter 3.11.2 --- Western blot --- p.58 / Chapter 3.11.3 --- Western blot analysis --- p.58 / Chapter Chapter 4 --- Results --- p.60 / Chapter 4.1 --- Transient assay of gene expression of MSP142 and MSPl19 --- p.60 / Chapter 4.1.1 --- Construction of the GUS fusion constructs --- p.60 / Chapter 4.1.2 --- Particle Bombardment --- p.63 / Chapter 4.2 --- Transgenic analysis of MSP142 and MSPl19 expression --- p.70 / Chapter 4.2.1 --- MSPl42 and MSPl19 constructs and transformation --- p.70 / Chapter 4.2.2 --- Selection of transgenic plants --- p.71 / Chapter 4.2.3 --- Southern analysis --- p.75 / Chapter 4.2.4 --- Northern analysis --- p.77 / Chapter 4.2.5 --- Western analysis --- p.79 / Chapter 4.3 --- Expression of the protein-targeting and GUS fused modified MSP1 constructs --- p.81 / Chapter 4.3.1 --- Construction of the fusion constructs --- p.81 / Chapter (A) --- Protein-targeting constructs --- p.81 / Chapter (B) --- GUS fusion constructs --- p.90 / Chapter B1. --- Constructs for transient assay --- p.90 / Chapter B2. --- Modification of GUS sequence --- p.96 / Chapter B3. --- Constructs for tobacco transformation --- p.100 / Chapter 4.4 --- Transient assay of GUS fused MP42 and MP19 constructs by particle Bombardment --- p.107 / Chapter 4.4.1 --- The GUS fusion constructs --- p.107 / Chapter 4.4.2 --- Modification of GUS --- p.112 / Chapter 4.5 --- Generation of transgenic tobacco --- p.116 / Chapter 4.6 --- Southern analysis --- p.120 / Chapter 4.7 --- Northern analysis --- p.126 / Chapter (A) --- Protein-targeting constructs --- p.126 / Chapter (B) --- GUS fusion constructs --- p.130 / Chapter 4.8 --- Western analysis --- p.133 / Chapter (A) --- Protein-targeting constructs --- p.133 / Chapter (B) --- GUS fusion constructs --- p.139 / Chapter Chapter 5 --- Discussion --- p.146 / Chapter Chapter 6 --- Conclusion --- p.157 / References --- p.158

by Lau On Sun. / Thesis submitted in: November 2003. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 117-127). / Abstracts in English and Chinese. / Acknowledgements --- p.iii / Abstract --- p.v / List of Abbreviations --- p.viii / Table of Contents --- p.x / List of Figures --- p.xiii / List of Tables --- p.xv / Chapter Chapter 1 --- General Introduction --- p.1 / Chapter Chapter 2 --- Literature Review --- p.3 / Chapter 2.1 --- Malaria --- p.3 / Chapter 2.1.1 --- Global situation --- p.3 / Chapter 2.1.2 --- Malaria parasite and its life cycle --- p.4 / Chapter 2.1.3 --- Need for a malarial vaccine --- p.5 / Chapter 2.2 --- Merozoite surface protein 1 and its fragments - the advanced malaria vaccine candidate --- p.7 / Chapter 2.2.1 --- Basic research on MSP1 --- p.7 / Chapter 2.2.2 --- Vaccine research on MSP1 --- p.8 / Chapter 2.3 --- Transgenic plants as recombinant protein production systems --- p.11 / Chapter 2.3.1 --- Characteristics --- p.11 / Chapter 2.3.2 --- Plant-based vaccine --- p.13 / Chapter 2.4 --- Expression of MSP 1 C-terminal fragments in transgenic plants --- p.15 / Chapter 2.4.1 --- Previous studies --- p.15 / Chapter 2.4.2 --- Plant-optimized MSP142 cDNA --- p.18 / Chapter 2.5 --- Phaseolin: its promoter and vacuolar-sorting signal --- p.20 / Chapter 2.6 --- Sorting of soluble protein to vacuoles in plants --- p.22 / Chapter 2.7 --- Winged bean lysine-rich protein and translational fusion strategy --- p.24 / Chapter 2.8 --- Hypotheses and aims of study --- p.26 / Chapter Chapter 3: --- Materials and Methods --- p.28 / Chapter 3.1 --- Introduction --- p.28 / Chapter 3.2 --- Chemicals --- p.28 / Chapter 3.3 --- Bacterial strains --- p.28 / Chapter 3.4 --- Chimeric gene construction --- p.29 / Chapter 3.4.1 --- Construction of the lysine-rich protein fusion constructs --- p.33 / Chapter 3.4.2 --- Construction of the phaseolin-targeting constructs --- p.37 / Chapter 3.4.3 --- Confirmation of sequence fidelity of chimeric genes --- p.42 / Chapter 3.4.4 --- Cloning of chimeric genes into Agrobacterium binary vector --- p.42 / Chapter 3.5 --- Transgenic expression in Arabidopsis and tobacco --- p.44 / Chapter 3.5.1 --- Plant materials --- p.44 / Chapter 3.5.2 --- Agrobacterium transformation --- p.44 / Chapter 3.5.3 --- Arabidopsis transformation and selection --- p.45 / Chapter 3.5.4 --- Tobacco Transformation and Selection --- p.47 / Chapter 3.5.5 --- Genomic DNA isolation --- p.49 / Chapter 3.5.6 --- Southern blot analysis --- p.49 / Chapter 3.5.7 --- Total silique RNA isolation --- p.50 / Chapter 3.5.8 --- Northern blot analysis --- p.50 / Chapter 3.5.9 --- Protein extraction and SDS-PAGE --- p.51 / Chapter 3.5.10 --- Western blot analysis --- p.52 / Chapter 3.5.11 --- Enterokinase digestion of recombinant LRP fusion protein --- p.53 / Chapter 3.5.12 --- Deglycosylation studies of recombinant MSP142-AFVY --- p.54 / Chapter 3.6 --- Confocal immunoflorescence studies of MSPl42-AFVY in tobacco --- p.55 / Chapter 3.6.1 --- Preparation of sections --- p.55 / Chapter 3.6.2 --- Labeling of fluorescence probes --- p.55 / Chapter 3.6.3 --- Image collection --- p.56 / Chapter 3.7 --- Bacterial expression of MSP 142 and anti-serum production --- p.57 / Chapter 3.7.1 --- pET expression in E. coli --- p.57 / Chapter 3.7.2 --- Purification of recombinant His-MSPl42 --- p.58 / Chapter 3.7.3 --- Immunization of rabbits --- p.59 / Chapter Chapter 4: --- Results --- p.60 / Chapter 4.1 --- Transgenic analysis of lysine-rich protein fusion constructs --- p.60 / Chapter 4.1.1 --- Construction of the lysine-rich protein fusion constructs --- p.60 / Chapter 4.1.2 --- Selection of transgenic plants --- p.62 / Chapter 4.1.3 --- Southern analysis --- p.65 / Chapter 4.1.4 --- Northern analysis --- p.69 / Chapter 4.1.5 --- Western analysis --- p.71 / Chapter 4.1.6 --- Western analysis with anti-LRP --- p.75 / Chapter 4.1.7 --- Enterokinase digestion of recombinant LRP fusion protein --- p.76 / Chapter 4.2 --- Transgenic analysis of phaseolin vacuolar-sorting signal constructs --- p.80 / Chapter 4.2.1 --- Construction of the phaseolin vacuolar-sorting signal constructs --- p.80 / Chapter 4.2.2 --- Selection of transgenic plants --- p.82 / Chapter 4.2.3 --- Southern analysis --- p.85 / Chapter 4.2.4 --- Northern analysis --- p.89 / Chapter 4.2.5 --- Western analysis --- p.91 / Chapter 4.2.6 --- Deglycosylation studies of recombinant MSPl42-AFVY --- p.96 / Chapter 4.2.7 --- Human serum detection of MSP142-AFVY --- p.100 / Chapter 4.3 --- Confocal immunofluorescence studies of MSP142-AFVY in tobacco --- p.102 / Chapter 4.4 --- Bacterial expression of MSPl42 and anti-serum production --- p.105 / Chapter 4.4.1 --- Expression and purification of recombinant His-MSPl42 in E. coli --- p.105 / Chapter 4.4.2 --- Titer and specificity of the anti-serum --- p.107 / Chapter Chapter 5 --- Discussion --- p.109 / Chapter Chapter 6 --- Conclusion --- p.116 / References --- p.117

Malaria affects over half of the world's population and causes half a million deaths annually, especially in Sub-Saharan Africa. Four species of the apicomplexan Plasmodium parasite (P. falciparum, P. ovale, P. malariae and P. vivax) are responsible for malaria in Africa. Both parasite and host factors contribute to heterogeneity in the risk of developing malaria, clinical manifestation of the disease as well as the number of treatments required to clear parasites. The epidemiology of the different species, and the role of exposure to mixed-species Plasmodium co-infections in generating heterogeneity remains poorly studied. Being an obligate intracellular parasite the blood-stage life cycle of the Plasmodium parasite takes place in the erythrocytes of the human host. The surfaces of these erythrocytes are the medically important ABO blood group antigens that have been reported to influence the susceptibility or otherwise of an individual developing severe malaria. In this thesis I have considered the contributions of the species of Plasmodium parasites and the ABO blood group of the host in driving heterogeneity in human malaria. The aims of this thesis were to determine: (i) the seroepidemiology of the different Plasmodium species in two mesoendemic African populations (Zimbabwe and Sudan); (ii) to determine if heterogeneity in clinical presentations of malaria (history of fever, body temperature and parasitaemia) and response to drug treatment is related to exposure to single vs. mixed-Plasmodium species infection; (iii) the spatial and temporal dynamics of malaria prevalence and Plasmodium species distribution in a mesoendemic village in eastern Sudan; (iv) gene expression changes in 3D7 P. falciparum parasites as they infect erythrocytes of different ABO blood group donors. For aims (i to iii) I developed an enzyme-linked immunosorbent assay using antigens derived from Plasmodium merozoite surface protein 1, also known as MSP-119, to detect IgG antibodies to all four malaria parasite species in Zimbabwean and Sudanese populations. In the Zimbabwean study, plasma samples from 100 individuals each (aged 5-18 years) from three villages (Burma Valley, Mutoko and Chiredzi) were screened for exposure to Plasmodium parasites. In Daraweesh, Sudan, plasma samples from 333 individuals (aged 1-74 years) who had experienced a first malaria episode between 1990 and 2000 were recruited into the study. For study aim (iv) I cultured a single clone of 3D7 P. falciparum parasite using erythrocytes of individuals of different ABO blood group types, harvested parasite RNA and sequenced it to determine gene expression changes in the different hosts. I showed that human IgG antibodies to MSP-119 antigens of the four Plasmodium species are species-specific and do not cross-react. In both study populations almost all antibody responses involved P. falciparum, and single-species responses were almost exclusively directed against P. falciparum antigens. Mixed-species responses accounted for more than a third of responses, and were associated with chloroquine treatment failure, with significantly high proportion of individuals with mixed-species infections requiring repeated treatment with chloroquine/sulfadoxine-pyrimethamine for parasite clearance. This finding highlights the need for a sensitive method for detecting mixed-species malaria infections to enable the assessment of the true prevalence and magnitude of the disease burden caused by the non-falciparum species in endemic populations. Drug treatment failures associated with mixed species infections have significant impact on malaria morbidity and mortality. Treatment failure or partial parasite clearance has the potential to allow dormant liver stages of P. vivax and P. ovale to become a source of parasite reservoir for onward transmission. Furthermore, untreated low-grade chronic infections caused by P. malariae have been reported to cause systemic diseases many years after the primary infection. Spatial analysis of malaria epidemiology showed that malaria parasite transmission in Daraweesh was focal, and that infections are not randomly distributed in the village. Two space-time clusters of significantly increased malaria risk were identified (1993- 1999, and 1998-1999) with marked variations between households, but little or no variation in the species of Plasmodium over time. Similarly, multiple significant clusters were identified for the parasite species; three for P. falciparum, two for P. vivax and P. malariae, and one for P. ovale. These clusters had overlapping time frames, with some of the species significantly infecting the same households. This suggests that even in a small geographic area malaria transmission shows heterogeneity, and that such data can provide useful information to guide malaria control efforts. Finally, I demonstrated that 3D7 P. falciparum parasite growth was similar in the erythrocytes of different blood group donors, and provide preliminary data to show that the non-coding RNA gene, PF3D7_1370800, is differentially expressed in blood group A donors relative to blood groups B and O donors. Further research is needed to better understand the role of this gene in malaria pathology. All together, these findings will aid malaria researchers and other stakeholders in making informed choices about tools for diagnosing Plasmodium species, and control programmes targeting eradication of malaria caused by all Plasmodium species, as is the case of incorporating these findings into current malaria research in Sudan.

Tam, Hou Si. / 33 in title is subscript. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 174-187). / Abstracts in English and Chinese. / THESIS COMMITTEE --- p.i / ACKNOWLEDGEMENTS --- p.ii / ABSTRACT --- p.iii / 摘要 --- p.v / TABLE OF CONTENTS --- p.vii / LIST OF FIGURES --- p.xii / LIST OF TABLES --- p.xvii / LIST OF ABBREVIATIONS --- p.xviii / CHAPTER / Chapter 1. --- INTRODUCTION / Chapter 1.1 --- Malaria --- p.1 / Chapter 1.2 --- Malaria is a public health problem --- p.1 / Chapter 1.3 --- Malarial parasite --- p.3 / Chapter 1.4 --- Life cycle of P. falciparum --- p.3 / Chapter 1.4.1 --- The pre-erythrocytic stage --- p.3 / Chapter 1.4.2 --- The asexual erythrocytic stage --- p.3 / Chapter 1.4.3 --- The sexual transmission stage --- p.6 / Chapter 1.5 --- Chemoprophylaxis and chemotherapy of malaria --- p.7 / Chapter 1.6 --- Drug resistance of malaria parasite --- p.7 / Chapter 1.7 --- The progress for malaria vaccine --- p.10 / Chapter 1.8 --- Vaccine candidates for asexual erythrocytic stage --- p.11 / Chapter 1.9 --- Merozoite Surface Protein-1 (MSP-1) --- p.13 / Chapter 1.9.1 --- Structure of MSP-1 --- p.13 / Chapter 1.9.2 --- The processing of MSP-1 --- p.17 / Chapter 1.9.3 --- MSP-1 as a blood-stage vaccine --- p.19 / Chapter 1.9.4 --- The vaccine potency of MSP-133 --- p.23 / Chapter 1.10 --- Merits of E. coli expression system --- p.25 / Chapter 1.11 --- Aim of study --- p.26 / Chapter 2. --- MATERIALS AND METHODS / Chapter 2.1 --- Materials --- p.30 / Chapter 2.2 --- Methods --- p.39 / Chapter 3. --- EXPRESSION AND PURIFICATION OF RECOMBINANT MSP-l33kv+19 PROTEIN / Chapter 3.1 --- Introduction --- p.63 / Chapter 3.2 --- Results / Chapter 3.2.1 --- Construction of pET32a/MSP-l33kv+19 expression vector --- p.64 / Chapter 3.2.2 --- SDS-PAGE analysis of the expressed protein --- p.74 / Chapter 3.2.3 --- Western blot analysis of the expressed protein --- p.78 / Chapter 3.2.4 --- Modification of the expression conditions --- p.78 / Chapter 3.2.5 --- Protein purification by IMAC --- p.82 / Chapter 3.2.6 --- Cleavage of fusion partner from the rMSP-133kv+19 protein --- p.82 / Chapter 3.2.7 --- Verification of non-fused recombinant MSPl33kv+19 protein by N-terminal amino acid sequencing --- p.86 / Chapter 3.2.8 --- Separation of target protein from the fusion mixture by IMAC --- p.86 / Chapter 3.2.9 --- Separation of digestion product by Size Exclusion Chromatography --- p.89 / Chapter 3.2.10 --- Conformational test of the purified protein --- p.89 / Chapter 3.2.11 --- Separation of target protein from contaminants by Anion-Exchange Chromatography --- p.92 / Chapter 3.2.12 --- Separation of target protein from contaminants by Immuno-Affinity Chromatography --- p.95 / Chapter 3.3 --- Conclusion --- p.95 / Chapter 4. --- IMMUNOLOGICAL CHARACTERIZATION OF BACTERIAL EXPRESSED rMSP-l33kv+19 / Chapter 4.1 --- Introduction --- p.97 / Chapter 4.2 --- Results / Chapter 4.2.1 --- Immunogenicity of recombinant NfMSP-133kV+19 protein --- p.98 / Chapter 4.2.2 --- Specificity of anti-NfMSP-133kv+19 sera to MSP-l33kv. MSP-l33 and MSP-l19 --- p.98 / Chapter 4.2.3 --- Cross reactivity of anti-MSP-133kv+19 and anti-BVp42 serum --- p.103 / Chapter 4.2.4 --- Competitive ELISA --- p.103 / Chapter 4.2.5 --- Test for the presence of inhibitory B-cell epitopes on rMSP-l33kv+19 --- p.111 / Chapter 4.2.6 --- In vitro parasitic growth inhibition assay --- p.113 / Chapter 4.3 --- Conclusion --- p.115 / Chapter 5. --- EXPRESSION AND PURIFICATION OF RECOMBINANT MSP-l33kc+19 PROTEIN / Chapter 5.1 --- Introduction --- p.116 / Chapter 5.2 --- Results / Chapter 5.2.1 --- Construction of pET32a/MSP-133kv+19 expression vector --- p.117 / Chapter 5.2.2 --- Expression of recombinant MSP-133kc+19 protien (rMSP-133kc+19) --- p.124 / Chapter 5.2.3 --- Purification of rMSP-l33kc+19 by IMAC --- p.127 / Chapter 5.2.4 --- Cleavage of fusion partner from target protein --- p.127 / Chapter 5.2.5 --- Construction of pRSETA/MSP-l3X33kc+19 expression vector --- p.135 / Chapter 5.2.6 --- SDS-PAGE analysis of the protein expression --- p.146 / Chapter 5.3 --- Conclusion --- p.153 / Chapter 6. --- DISCUSSION / Chapter 6.1 --- Expression of rMSP-l33kv+19 --- p.154 / Chapter 6.2 --- Purification of rMSP-l3.3kv+19 --- p.156 / Chapter 6.3 --- Conformational test of rMSP-133kv+19 --- p.157 / Chapter 6.4 --- Biological and immunological activity of NfMSP-133kv+19 --- p.158 / Chapter 6.5 --- Expression of rMSP-133kc+19 --- p.166 / Chapter 6.6 --- Future prospects --- p.167 / REFERENCES --- p.174 / APPENDICES / Chapter 1. --- HiTrap NHS-activated HP for ligand coupling procedure --- p.188 / Chapter 2. --- Reuse of Ni+-NTA Resin procedure --- p.190 / Chapter 3. --- Sequence alignment of MSP-133 (MAD20 & Welcome/Kl alleles) --- p.191 / Chapter 4. --- Nucleotide sequence and amino acid sequence of P. falciparum MSP-l33kv+19 --- p.192 / Chapter 5. --- Nucleotide sequence and amino acid sequence of P. falciparum MSP-l33kc+19 --- p.193 / Chapter 6. --- "Nucleotide sequence and amino acid sequence of P. falciparum MSP-142 (3D7 isolate, MAD20 allele)" --- p.194 / Chapter 7. --- Amino acid sequence of Plasmodium falciparum MSP-l42 --- p.195

In den Jahren 1998 bis 2004 wurden auf der Insel Flores (Indonesien) vereinzelt klinische und laborchemische Untersuchungen auf Malaria bei Kindern und Jugendlichen durchgeführt, dabei wurde eine Malariaprävalenz zwischen 59 % und 81 % festgestellt. Vor diesem Hintergrund entstand aus der Kooperation der lokalen Stiftung YASPEM, dem Missionsärztlichen Institut Würzburg und Misereor e.V. ein groß angelegtes Malariakontrollprogramm, das im Herbst 2007 seine Arbeit aufnahm. Ziel des Programms war es, die Malariaprävalenz erneut zu überprüfen und diese durch ein umfassendes Konzept mit Aufklärungskampagnen, flächendeckenden Blutuntersuchungen, medizinischer Behandlung und Vektorkontrollmaßnahmen nachhaltig zu senken. Ziel dieser Dissertation ist dabei, eine Evaluation der gewonnenen Daten durchzuführen und anhand dieser Handlungsempfehlungen für Folgeprojekte herauszuarbeiten. In der Evaluation zeigte sich, dass die tatsächliche Prävalenz weit unter den zuvor angegebenen Raten lag: Im Dorf Waiara war die Prävalenz mit 13,2 % am höchsten, in den übrigen untersuchten Dörfern (Namang Kewa, Geliting, Kopong, Iantena, Umagera) lag sie zwischen 1,2 % und 3,5 %. Zurückzuführen ist diese Diskrepanz auf verschieden Ursachen. Zum einen wird die Diagnose „Malaria“ häufig klinisch gestellt, es subsummieren sich viele andere fieberhafte Erkrankungen unter dieser Diagnose. Des Weiteren zeigte sich eine hohe Rate an falsch positiven Befunden des Labors des lokalen Krankenhauses im Vergleich zu den Laborergebnissen des Malariakontrollprogramms. In der weiteren Evaluation konnten geographische, demographische und jahreszeitliche Schwerpunkte für die Malariaarbeit auf Flores herausgearbeitet werden: •Es gab eine signifikante Häufung der Malariafälle in geographisch besonders prädestinierten Gebieten. •Zudem waren signifikant mehr Kinder und Jugendliche von Malaria betroffen als Erwachsene. •Die Malariainfektionen traten vornehmlich in der Regenzeit auf, in der Trockenzeit sank die Prävalenz in allen untersuchten Gebieten ab. Durch das umfassende Malariakontrollprogramm konnte in stark betroffenen Regionen ein Erfolg im Sinne eines signifikanten Rückgangs der Prävalenz verzeichnet werden. / In the years 1998 to 2004, on the island of Flores (Indonesia), isolated clinical and laboratory studies on malaria in children and adolescents were performed. Thereby, a malaria prevalence between 59% and 81 % was found. Against this background, a cooperation of the local YASPEM Foundation, the Medical Mission Institute Würzburg and Misereor e. V. was established and a large-scale malaria control program was brought into being. The program started in autumn 2007 at the beginning of the rainy season. The program's objective was to reassess the prevalence of malaria and to reduce malaria infections using a comprehensive approach, including education campaigns, mass blood tests, medical treatment and vector control measures. The aim of this thesis is to conduct an evaluation of the data and to work out recommendations for future malaria projects. The evaluation showed that the actual malaria prevalence was much lower than detected before. In the village Waiara the prevalence was the highest with 13.2%; in the other villages surveyed (Namang Kewa, Geliting, Kopong, Iantena, Umagera) it ranged between 1.2% and 3.5%. This discrepancy has a variety of reasons. First, malaria is often diagnosed clinically without further testing. There are many other feverish diseases subsumed under this diagnosis. In addition, the laboratory of the local hospital showed a high rate of false positive results compared to the laboratory of the malaria control program. Furthermore, it could be shown that the malaria work on Flores was focused differently, according to geographical, demographic and seasonal conditions. •There was a significant accumulation of cases of malaria in geographically very predestined areas. •Significantly more children and adolescents were affected by malaria compared to adults. •Malaria infections occurred mainly in the rainy season, in the dry season the prevalence decreased. In summary, the comprehensive malaria control program could decline malaria prevalence significantly in certain areas and is therefore a success.

Determina la eficacia de las pruebas DELI y MSF para calcular la IC50 de drogas antimaláricas mefloquina, quinina y cloroquina obtenidas de aislamientos de P. falciparum provenientes de pobladores de la comunidad de Padre Cocha en Iquitos-Perú. Se realizó un estudio cuantitativo descriptivo, prospectivo de corte transversal. La muestra fueron 16 muestras de sangre con diagnóstico de malaria confirmado por gota gruesa. Se realizaron los dos ensayos de sensibilidad in vitro (DELI y MSF) a cada muestra. Se determinaron tres factores de eficacia para el presente estudio; porcentaje de éxito, coeficiente de determinación de curva (R2) y coeficiente de variación (CV). Se hizo un análisis descriptivo y estadístico de los factores de eficacia mediante las pruebas de Wilcoxon y McNemar- Bowker para muestras pareadas con p < 0.05. Las medias aritméticas de los valores de IC50 con el ensayo DELI fueron para cloroquina 231.26 nM, quinina 101.17 nM y mefloquina 16.03 nM. Las medias de los valores de IC50 con el ensayo MSF fueron para cloroquina 227.52 nM, quinina 142.46 nM y mefloquina 35.07 nM. El porcentaje de éxito del cálculo de la IC50 para las tres drogas fueron el 50% (8/16) y 87.5% (14/16) en los ensayos MSF y DELI respectivamente, estas diferencias fueron estadísticamente significativas (p < 0.05). Sin embargo, en el análisis entre los porcentajes de éxito entre drogas, no presentaron diferencias para CQ y QN y si presentaron diferencias para MQ (p < 0.05). No hay diferencias significativas entre los valores de R2 entre las pruebas MSF y DELI. El porcentaje de éxito de CV positivos aumentó de 37.5% con el ensayo MSF a 81.25% con el ensayo DELI, estas diferencias fueron significativas (p < 0.05). Se concluye que el ensayo DELI es más eficaz que el ensayo MSF para calcular la IC50 de las drogas CQ, QN Y MQ. / Tesis