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  1. Article ; Online: Meta-Analysis of Human Antibodies Against

    Takashima, Eizo / Kanoi, Bernard N / Nagaoka, Hikaru / Morita, Masayuki / Hassan, Ifra / Palacpac, Nirianne M Q / Egwang, Thomas G / Horii, Toshihiro / Gitaka, Jesse / Tsuboi, Takafumi

    Frontiers in immunology

    2022  Volume 13, Page(s) 887219

    Abstract: Concerted efforts to fight malaria have caused significant reductions in global malaria cases and mortality. Sustaining this will be critical to avoid rebound and outbreaks of seasonal malaria. Identifying predictive attributes that define clinical ... ...

    Abstract Concerted efforts to fight malaria have caused significant reductions in global malaria cases and mortality. Sustaining this will be critical to avoid rebound and outbreaks of seasonal malaria. Identifying predictive attributes that define clinical malaria will be key to guide development of second-generation tools to fight malaria. Broadly reactive antibodies against variable surface antigens that are expressed on the surface of infected erythrocytes and merozoites stage antigens are targets of naturally acquired immunity and prime candidates for anti-malaria therapeutics and vaccines. However, predicting the relationship between the antigen-specific antibodies and protection from clinical malaria remains unresolved. Here, we used new datasets and multiple approaches combined with re-analysis of our previous data to assess the multi-dimensional and complex relationship between antibody responses and clinical malaria outcomes. We observed 22 antigens (17 PfEMP1 domains, 3 RIFIN family members, merozoite surface protein 3 (PF3D7_1035400), and merozoites-associated armadillo repeats protein (PF3D7_1035900) that were selected across three different clinical malaria definitions (1,000/2,500/5,000 parasites/µl plus fever). In addition, Principal Components Analysis (PCA) indicated that the first three components (Dim1, Dim2 and Dim3 with eigenvalues of 306, 48, and 29, respectively) accounted for 66.1% of the total variations seen. Specifically, the Dim1, Dim2 and Dim3 explained 52.8%, 8.2% and 5% of variability, respectively. We further observed a significant relationship between the first component scores and age with antibodies to PfEMP1 domains being the key contributing variables. This is consistent with a recent proposal suggesting that there is an ordered acquisition of antibodies targeting PfEMP1 proteins. Thus, although limited, and further work on the significance of the selected antigens will be required, these approaches may provide insights for identification of drivers of naturally acquired protective immunity as well as guide development of additional tools for malaria elimination and eradication.
    MeSH term(s) Animals ; Antibodies/metabolism ; Humans ; Malaria ; Malaria, Falciparum ; Merozoites ; Plasmodium falciparum ; Protozoan Proteins
    Chemical Substances Antibodies ; Protozoan Proteins
    Language English
    Publishing date 2022-06-09
    Publishing country Switzerland
    Document type Journal Article ; Meta-Analysis ; Research Support, Non-U.S. Gov't
    ZDB-ID 2606827-8
    ISSN 1664-3224 ; 1664-3224
    ISSN (online) 1664-3224
    ISSN 1664-3224
    DOI 10.3389/fimmu.2022.887219
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Characterization of a Plasmodium falciparum PHISTc protein, PF3D7_0801000, in blood- stage malaria parasites.

    Nagaoka, Hikaru / Kanoi, Bernard N / Morita, Masayuki / Nakata, Takahiro / Palacpac, Nirianne M Q / Egwang, Thomas G / Horii, Toshihiro / Tsuboi, Takafumi / Takashima, Eizo

    Parasitology international

    2020  Volume 80, Page(s) 102240

    Abstract: ... region of PF3D7_0801000 (G ...

    Abstract During intraerythrocytic development Plasmodium falciparum deploys numerous proteins to support erythrocyte invasion, intracellular growth and development, as well as host immune evasion. Since these proteins are key for parasite intraerythrocytic survival and propagation, they represent attractive targets for antimalarial vaccines. In this study we sought to characterize a member of the PHISTc family of proteins, PF3D7_0801000, as a potential vaccine target. Using the wheat germ cell-free system we expressed the N-terminal region of PF3D7_0801000 (G
    MeSH term(s) Antibodies, Protozoan/analysis ; Malaria Vaccines/chemical synthesis ; Malaria, Falciparum/prevention & control ; Merozoites/chemistry ; Plasmodium falciparum/chemistry ; Protozoan Proteins/analysis
    Chemical Substances Antibodies, Protozoan ; Malaria Vaccines ; Protozoan Proteins
    Language English
    Publishing date 2020-11-02
    Publishing country Netherlands
    Document type Journal Article
    ZDB-ID 1363151-2
    ISSN 1873-0329 ; 1383-5769
    ISSN (online) 1873-0329
    ISSN 1383-5769
    DOI 10.1016/j.parint.2020.102240
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Using the Ultrasensitive Alere Plasmodium falciparum Malaria Ag HRP-2

    Owalla, Tonny Jimmy / Okurut, Emmanuel / Apungia, Gonzaga / Ojakol, Basil / Lema, Jimmy / C Murphy, Sean / G Egwang, Thomas

    The American journal of tropical medicine and hygiene

    2020  Volume 103, Issue 2, Page(s) 778–784

    Abstract: The ultrasensitive ... ...

    Abstract The ultrasensitive Alere
    MeSH term(s) Adolescent ; Adult ; Antigens, Protozoan/immunology ; Asymptomatic Infections ; Child ; Child, Preschool ; False Positive Reactions ; Female ; Humans ; Infant ; Malaria, Falciparum/diagnosis ; Male ; Microscopy ; Parasitemia/diagnosis ; Plasmodium falciparum/genetics ; Plasmodium falciparum/immunology ; Plasmodium falciparum/isolation & purification ; Protozoan Proteins/immunology ; RNA, Ribosomal, 18S/genetics ; Reproducibility of Results ; Reverse Transcriptase Polymerase Chain Reaction ; Sensitivity and Specificity ; Time Factors ; Uganda
    Chemical Substances Antigens, Protozoan ; HRP-2 antigen, Plasmodium falciparum ; Protozoan Proteins ; RNA, Ribosomal, 18S
    Language English
    Publishing date 2020-06-25
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2942-7
    ISSN 1476-1645 ; 0002-9637
    ISSN (online) 1476-1645
    ISSN 0002-9637
    DOI 10.4269/ajtmh.19-0653
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Global Repertoire of Human Antibodies Against

    Kanoi, Bernard N / Nagaoka, Hikaru / White, Michael T / Morita, Masayuki / Palacpac, Nirianne M Q / Ntege, Edward H / Balikagala, Betty / Yeka, Adoke / Egwang, Thomas G / Horii, Toshihiro / Tsuboi, Takafumi / Takashima, Eizo

    Frontiers in immunology

    2020  Volume 11, Page(s) 893

    Abstract: Clinical immunity to malaria develops after repeated exposure ... ...

    Abstract Clinical immunity to malaria develops after repeated exposure to
    MeSH term(s) Adolescent ; Antibodies, Protozoan/blood ; Antibodies, Protozoan/immunology ; Antibody Formation ; Antigens, Protozoan/immunology ; Child ; Female ; Humans ; Immunity, Innate ; Malaria, Falciparum/immunology ; Male ; Membrane Proteins/immunology ; Plasmodium falciparum/immunology ; Prospective Studies ; Protozoan Proteins/immunology ; Uganda ; Young Adult
    Chemical Substances Antibodies, Protozoan ; Antigens, Protozoan ; Membrane Proteins ; Protozoan Proteins ; RIFIN protein, Plasmodium falciparum ; STEVOR antigen, Plasmodium falciparum
    Language English
    Publishing date 2020-05-12
    Publishing country Switzerland
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2606827-8
    ISSN 1664-3224 ; 1664-3224
    ISSN (online) 1664-3224
    ISSN 1664-3224
    DOI 10.3389/fimmu.2020.00893
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article: Safety, immunogenicity, and cross-species protection of a plasmid DNA encoding Plasmodium falciparum SERA5 polypeptide, microbial epitopes and chemokine genes in mice and olive baboons.

    Onkoba, Nyamongo / M Mumo, Ruth / Ochanda, Horace / Omwandho, Charles / S Ozwara, Hastings / G Egwang, Thomas

    Journal of biomedical research

    2017  Volume 31, Issue 4, Page(s) 321–332

    Abstract: ... were used to determine cross-species efficacy, and T cell phenotypes, Th1-, Th2-type, T-regulatory ... vaccines were safe and induced Th1-, Th2-type, and T-regulatory responses vaccinated animals showed ...

    Abstract Incorporation of biomolecular epitopes to malarial antigens should be explored in the development of strain-transcending malarial vaccines. The present study sought to determine safety, immunogenicity and cross-species efficacy ofPlasmodium falciparum serine repeat antigen 5 polypeptide co-expressed with epitopes of Bacille-Calmette Guerin (BCG), tetanus toxoid (TT) and a chemokine gene. Olive baboons and BALB/c mice were randomly assigned into vaccine and control groups. The vaccine group animals were primed and boosted twice with pIRES plasmids encoding the SERA5+ BCG+ TT alone, or with either CCL5 or CCL20 and the control group with pIRES plasmid vector backbone. Mice and baboons were challenged withP. berghei ANKA and P. knowlesi H strain parasites, respectively. Safety was determined by observing for injection sites reactogenicities, hematology and clinical chemistry. Parasitaemia and survivorship profiles were used to determine cross-species efficacy, and T cell phenotypes, Th1-, Th2-type, T-regulatory immune responses and antibody responses were assessed to determine vaccine immunogenicity. The pSeBCGTT plasmid DNA vaccines were safe and induced Th1-, Th2-type, and T-regulatory responses vaccinated animals showed enhanced CD4
    Language English
    Publishing date 2017-06-24
    Publishing country China
    Document type Journal Article
    ZDB-ID 2555537-6
    ISSN 1876-4819 ; 1674-8301
    ISSN (online) 1876-4819
    ISSN 1674-8301
    DOI 10.7555/JBR.31.20160025
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Immunogenicity and protection from malaria infection in BK-SE36 vaccinated volunteers in Uganda is not influenced by HLA-DRB1 alleles.

    Tougan, Takahiro / Ito, Kazuya / Palacpac, Nirianne Marie Q / Egwang, Thomas G / Horii, Toshihiro

    Parasitology international

    2016  Volume 65, Issue 5 Pt A, Page(s) 455–458

    Abstract: SE36 antigen, derived from serine repeat antigen 5 (SERA5) of Plasmodium falciparum, is a promising blood stage malaria vaccine candidate. Designated as BK-SE36, the SE36 antigen was formulated with aluminum hydroxyl gel (AHG) and produced under Good ... ...

    Abstract SE36 antigen, derived from serine repeat antigen 5 (SERA5) of Plasmodium falciparum, is a promising blood stage malaria vaccine candidate. Designated as BK-SE36, the SE36 antigen was formulated with aluminum hydroxyl gel (AHG) and produced under Good Manufacturing Practice (GMP) constraints. In a Phase Ib clinical trial and follow-up study in Uganda, the risk for malaria symptoms was reduced by 72% compared with the control group. Although promising, the number of responders to the vaccine in 6-20years-olds was approximately 30% with the majority in the younger cohort. This is in contrast to the phase Ia clinical trial where response to the vaccine was 100% in Japanese malaria naive adults. A consideration that can be of importance is the involvement of host genetic factors that may influence the ability to mount an effective immune response to vaccination as well as susceptibility to malaria infection. We, therefore, analyzed allelic polymorphism of human leukocyte antigen (HLA)-DRB1 alleles using sequence-based typing (SBT). In this study, DRB1 alleles did not influence antibody response to BK-SE36 and the vaccinees susceptibility to clinical malaria.
    MeSH term(s) Adolescent ; Adult ; Alleles ; Antibodies, Protozoan/blood ; Antigens, Protozoan/immunology ; Child ; Female ; HLA-DRB1 Chains/genetics ; HLA-DRB1 Chains/immunology ; Humans ; Immunoglobulin G/blood ; Malaria Vaccines/immunology ; Malaria, Falciparum/immunology ; Male ; Plasmodium falciparum/immunology ; Uganda ; Vaccination ; Young Adult
    Chemical Substances Antibodies, Protozoan ; Antigens, Protozoan ; HLA-DRB1 Chains ; Immunoglobulin G ; Malaria Vaccines ; serine repeat antigen 5, Plasmodium falciparum
    Language English
    Publishing date 2016-10
    Publishing country Netherlands
    Document type Clinical Trial, Phase I ; Journal Article
    ZDB-ID 1363151-2
    ISSN 1873-0329 ; 1383-5769
    ISSN (online) 1873-0329
    ISSN 1383-5769
    DOI 10.1016/j.parint.2016.06.012
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Audio / Video: Biotechnology issues in Africa

    Egwang, T.G

    Electronic journal of biotechnology EJB. Dec 15, 2001. v. 4 (3)

    2001  

    Keywords food crops ; genetic engineering ; gene transfer ; transgenic plants ; tissue culture ; micropropagation ; genetic transformation ; biotechnology ; industrial crops ; Africa
    Language English
    Dates of publication 2001-1215
    Size p. N/A.
    Document type Article ; Audio / Video
    ZDB-ID 2020598-3
    ISSN 0717-3458
    ISSN 0717-3458
    Database NAL-Catalogue (AGRICOLA)

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  8. Article ; Online: Comprehensive analysis of antibody responses to Plasmodium falciparum erythrocyte membrane protein 1 domains.

    Kanoi, Bernard N / Nagaoka, Hikaru / Morita, Masayuki / White, Michael T / Palacpac, Nirianne M Q / Ntege, Edward H / Balikagala, Betty / Yeka, Adoke / Egwang, Thomas G / Horii, Toshihiro / Tsuboi, Takafumi / Takashima, Eizo

    Vaccine

    2018  Volume 36, Issue 45, Page(s) 6826–6833

    Abstract: Acquired antibodies directed towards antigens expressed on the surface of merozoites and infected erythrocytes play an important role in protective immunity to Plasmodium falciparum malaria. P. falciparum erythrocyte membrane protein 1 (PfEMP1), the ... ...

    Abstract Acquired antibodies directed towards antigens expressed on the surface of merozoites and infected erythrocytes play an important role in protective immunity to Plasmodium falciparum malaria. P. falciparum erythrocyte membrane protein 1 (PfEMP1), the major parasite component of the infected erythrocyte surface, has been implicated in malaria pathology, parasite sequestration and host immune evasion. However, the extent to which unique PfEMP1 domains interact with host immune response remains largely unknown. In this study, we sought to comprehensively understand the naturally acquired antibody responses targeting different Duffy binding-like (DBL), and Cysteine-rich interdomain region (CIDR) domains in a Ugandan cohort. Consequently, we created a protein library consisting of full-length DBL (n = 163) and CIDR (n = 108) domains derived from 62-var genes based on 3D7 genome. The proteins were expressed by a wheat germ cell-free system; a system that yields plasmodial proteins that are comparatively soluble, intact, biologically active and immunoreactive to human sera. Our findings suggest that all PfEMP1 DBL and CIDR domains, regardless of PfEMP1 group, are targets of naturally acquired immunity. The breadth of the immune response expands with children's age. We concurrently identified 10 DBL and 8 CIDR domains whose antibody responses were associated with reduced risk to symptomatic malaria in the Ugandan children cohort. This study highlights that only a restricted set of specific domains are essential for eliciting naturally acquired protective immunity in malaria. In light of current data, tandem domains in PfEMP1s PF3D7_0700100 and PF3D7_0425800 (DC4) are recommended for extensive evaluation in larger population cohorts to further assess their potential as alternative targets for malaria vaccine development.
    MeSH term(s) Age Factors ; Antibodies, Protozoan/immunology ; Antibody Formation/immunology ; Child ; Female ; Humans ; Malaria/immunology ; Malaria/prevention & control ; Malaria Vaccines/therapeutic use ; Male ; Plasmodium falciparum/immunology ; Plasmodium falciparum/metabolism ; Plasmodium falciparum/pathogenicity ; Prospective Studies ; Protozoan Proteins/immunology ; Uganda
    Chemical Substances Antibodies, Protozoan ; Malaria Vaccines ; Protozoan Proteins ; erythrocyte membrane protein 1, Plasmodium falciparum
    Language English
    Publishing date 2018-09-24
    Publishing country Netherlands
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 605674-x
    ISSN 1873-2518 ; 0264-410X
    ISSN (online) 1873-2518
    ISSN 0264-410X
    DOI 10.1016/j.vaccine.2018.08.058
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: The N-Terminal Region of

    Nagaoka, Hikaru / Kanoi, Bernard N / Jinoka, Kana / Morita, Masayuki / Arumugam, Thangavelu U / Palacpac, Nirianne M Q / Egwang, Thomas G / Horii, Toshihiro / Tsuboi, Takafumi / Takashima, Eizo

    Frontiers in immunology

    2019  Volume 10, Page(s) 2669

    Abstract: Clinical manifestation of malaria is mainly due to intra-erythrocytic development ... ...

    Abstract Clinical manifestation of malaria is mainly due to intra-erythrocytic development of
    MeSH term(s) Antibodies, Protozoan/immunology ; Antigens, Protozoan/immunology ; Erythrocytes/parasitology ; Host-Parasite Interactions/physiology ; Humans ; Malaria Vaccines/immunology ; Malaria, Falciparum/immunology ; Plasmodium falciparum/immunology
    Chemical Substances Antibodies, Protozoan ; Antigens, Protozoan ; Malaria Vaccines
    Language English
    Publishing date 2019-11-20
    Publishing country Switzerland
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2606827-8
    ISSN 1664-3224 ; 1664-3224
    ISSN (online) 1664-3224
    ISSN 1664-3224
    DOI 10.3389/fimmu.2019.02669
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Plasmodium malariae and Plasmodium ovale infections and their association with common red blood cell polymorphisms in a highly endemic area of Uganda.

    Subissi, Lorenzo / Kanoi, Bernard N / Balikagala, Betty / Egwang, Thomas G / Oguike, Mary / Verra, Federica / Proietti, Carla / Bousema, Teun / Drakeley, Chris J / Sepúlveda, Nuno

    Transactions of the Royal Society of Tropical Medicine and Hygiene

    2019  Volume 113, Issue 7, Page(s) 370–378

    Abstract: Background: Plasmodium ovale and Plasmodium malariae infections are scarcely studied in sub-Saharan Africa, where the Plasmodium falciparum species predominates. The objective of this study is to investigate the prevalence of P. ovale and P. malariae ... ...

    Abstract Background: Plasmodium ovale and Plasmodium malariae infections are scarcely studied in sub-Saharan Africa, where the Plasmodium falciparum species predominates. The objective of this study is to investigate the prevalence of P. ovale and P. malariae infections and their relationship with common red blood cell polymorphisms in a cohort of 509 individuals from Uganda.
    Methods: Three cross-sectional surveys were conducted in individuals of 1-10 and >20 y of age from the Apac district at baseline and 6 and 16 weeks after drug treatment. Malaria infections were assessed by polymerase chain reaction and genotyping was performed for the sickle-cell allele, α-thalassaemia and glucose-6-phosphate dehydrogenase.
    Results: At baseline, the prevalence of infection was 7.5%, 12.6% and 57.4% for P. ovale, P. malariae and P. falciparum species, respectively. Co-infections were present in 14.1% of individuals, all including P. falciparum parasites. In children 1-5 y of age, the prevalence of P. ovale mono-infections increased significantly from 1.7% to 7.3% over time (p=0.004) while the prevalence of P. malariae and P. falciparum infections declined significantly during this study. After adjusting for confounding and multiple testing, only α-thalassaemia had a statistically significant increase in the odds of P. falciparum infections (odds ratio 1.93 [95% confidence interval 1.26 to 2.94]).
    Conclusions: Common red blood cell polymorphisms do not show strong effects on mild Plasmodium infections in this Ugandan population. To understand the extent of this result, similar studies should be carried out in other populations using larger cohorts.
    MeSH term(s) Adolescent ; Child ; Child, Preschool ; Cross-Sectional Studies ; Erythrocytes/microbiology ; Erythrocytes, Abnormal/microbiology ; Female ; Health Surveys ; Humans ; Infant ; Malaria, Falciparum/epidemiology ; Malaria, Falciparum/parasitology ; Male ; Plasmodium falciparum/isolation & purification ; Plasmodium ovale/isolation & purification ; Polymerase Chain Reaction ; Polymorphism, Genetic ; Uganda/epidemiology ; Young Adult
    Language English
    Publishing date 2019-04-05
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 441375-1
    ISSN 1878-3503 ; 0035-9203
    ISSN (online) 1878-3503
    ISSN 0035-9203
    DOI 10.1093/trstmh/trz015
    Database MEDical Literature Analysis and Retrieval System OnLINE

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