Browsing by Author "Nassuuna, Jacent"
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Item Candidate gene family-based and case-control studies of susceptibility to high Schistosoma mansoni worm burden in African children(AAS open research, 2021) Nyangiri, Oscar A.; Sokouri, A. Edwige; Koffi, Mathurin; Mewamba, Estelle; Simo, Gustave; Namulondo, Joyce; Mulindwa, Julius; Nassuuna, Jacent; Alison, Elliott; Karume, Kévin; Mumba, Dieudonne; M. Casacuberta-Partal; Dam, G. J. van; Bruno, Bucheton; Harry, Noyes; Matovu, EnockBackground: Approximately 25% of the risk of Schistosoma mansoni is associated with host genetic variation. We will test 24 candidate genes, mainly in the T h2 and T h17 pathways, for association with S. mansoni infection intensity in four African countries, using family based and case-control approaches. Methods: Children aged 5-15 years will be recruited in S. mansoni endemic areas of Ivory Coast, Cameroon, Uganda and the Democratic Republic of Congo (DRC). We will use family based (study 1) and case-control (study 2) designs. Study 1 will take place in Ivory Coast, Cameroon, Uganda and the DRC. We aim to recruit 100 high worm burden families from each country except Uganda, where a previous study recruited at least 40 families. For phenotyping, cases will be defined as the 20% of children in each community with heaviest worm burdens as measured by the circulating cathodic antigen (CCA) assay. Study 2 will take place in Uganda. We will recruit 500 children in a highly endemic community. For phenotyping, cases will be defined as the 20% of children with heaviest worm burdens as measured by the CAA assay, while controls will be the 20% of infected children with the lightest worm burdens. Deoxyribonucleic acid (DNA) will be genotyped on the Illumina H3Africa SNP (single nucleotide polymorphisms) chip and genotypes will be converted to sets of haplotypes that span the gene region for analysis. We have selected 24 genes for genotyping that are mainly in the Th2 and Th17 pathways and that have variants that have been demonstrated to be or could be associated with Schistosoma infection intensity. Analysis: In the family-based design, we will identify SNP haplotypes disproportionately transmitted to children with high worm burden. Case-control analysis will detect overrepresentation of haplotypes in extreme phenotypes with correction for relatedness by using whole genome principal components.Item The Effect of Helminth Infections and Their Treatment on Metabolic Outcomes: Results of a Cluster-Randomized Trial(Clinical infectious diseases, 2020) Sanya, Richard E.; Webb, Emily L.; Zziwa, Christopher; Kizindo, Robert; Sewankambo, Moses; Tumusiime, Josephine; Nakazibwe, Esther; Oduru, Gloria; Niwagaba, Emmanuel; Nakawungu, Prossy Kabuubi; Kabagenyi, Joyce; Nassuuna, Jacent; Walusimbi, Bridgious; Andia-Biraro, Irene; Elliot, Alison M.Helminths may protect against cardiometabolic risk through effects on inflammation and metabolism; their treatment may be detrimental to metabolic outcomes. In a cluster-randomized trial in 26 Ugandan fishing communities we investigated effects of community-wide intensive (quarterly single-dose praziquantel, triple-dose albendazole) vs standard (annual single-dose praziquantel, biannual single-dose albendazole) anthelminthic treatment on metabolic outcomes, and observational associations between helminths and metabolic outcomes. The primary outcome, homeostatic model assessment of insulin resistance (HOMA-IR), and secondary outcomes (including blood pressure, fasting blood glucose, lipids) were assessed after 4 years' intervention among individuals aged ≥10 years. We analyzed 1898 participants. Intensive treatment had no effect on HOMA-IR (adjusted geometric mean ratio, 0.96 [95% confidence interval {CI}, .86–1.07]; P = .42) but resulted in higher mean low-density lipoprotein cholesterol (LDL-c) (2.86 vs 2.60 mmol/L; adjusted mean difference, 0.26 [95% CI, −.03 to .56]; P = .08). Lower LDL-c levels were associated with Schistosoma mansoni (2.37 vs 2.80 mmol/L; −0.25 [95% CI, −.49 to −.02]; P = .04) or Strongyloides (2.34 vs 2.69 mmol/L; −0.32 [95% CI, −.53 to −.12]; P = .003) infection. Schistosoma mansoni was associated with lower total cholesterol (4.24 vs 4.64 mmol/L; −0.25 [95% CI, −.44 to −.07]; P = .01) and moderate to heavy S. mansoni infection with lower triglycerides, LDL-c, and diastolic blood pressure. Helminth infections improve lipid profiles and may lower blood pressure. Studies to confirm causality and investigate mechanisms may contribute to understanding the epidemiological transition and suggest new approaches to prevent cardiometabolic disease.Item High prevalence of Schistosoma mansoni infection and stunting among school age children in communities along the Albert-Nile, Northern Uganda: A cross sectional study(PLoS neglected tropical diseases, 2022) Mulindwa, Julius; Namulondo, Joyce; Kitibwa, Anna; Nassuuna, Jacent; Asanya Nyangiri, Oscar; Kimuda, Magambo Phillip; Boobo, Alex; Nerima, Barbara; Busingye, Fred; Rowel, Candia; Namukuta, Annet; Ssenyonga, Ronald; Ukumu, Noah; Paul, Ajal; Adriko, Moses; Harry, Noyes; Claudia, J. de Dood; Paul, L. A. M. CorstjensBackground Knowing the prevalence of schistosomiasis is key to informing programmes to control and eliminate the disease as a public health problem. It is also important to understand the impact of infection on child growth and development in order to allocate appropriate resources and effort to the control of the disease. Methods We conducted a survey to estimate the prevalence of schistosomiasis among school aged children in villages along the Albert-Nile shore line in the district of Pakwach, North Western Uganda. A total of 914 children aged between 10–15 years were screened for Schistosoma mansoni using the POC-CCA and Kato Katz (KK) techniques. The infection intensities were assessed by POC-CCA and KK as well as CAA tests. The KK intensities were also correlated with POC-CCA and with CAA intensity. Anthropometric measurements were also taken and multivariate analysis was carried out to investigate their association with infection status. Results The prevalence of schistosomiasis using the POC-CCA diagnostic test was estimated at 85% (95% CI: 83–87), being highest amongst children living closer to the Albert-Nile shoreline. Visual scoring of the POC-CCA results was more sensitive than the Kato Katz test and was positively correlated with the quantified infection intensities by the CAA test. The majority of the children were underweight (BMI<18.5), and most notably, boys had significantly lower height for age (stunting) than girls in the same age range (p < 0.0001), but this was not directly associated with S. mansoni infection. Conclusion High prevalence of S. mansoni infection in the region calls for more frequent mass drug administration with praziquantel. We observed high levels of stunting which was not associated with schistosomiasis. There is a need for improved nutrition among the children in the area.Item Risk Assessment for the Implementation of Controlled Human Schistosoma Mansoni Infection Trials in Uganda(AAS open research, 2019) Koopman, Jan Pieter; Egesa, Moses; Wajja, Anne; Adriko, Moses; Nassuuna, Jacent; Nkurunungi, Gyaviira; Driciru, Emmanuella; Cose, Stephen; Kaleebu, Pontiano; Kabatereine, Narcis; Tukahebwa, Edridah; Elliott, Alison M.Schistosomiasis is a parasitic infection highly prevalent in sub-Saharan Africa, and a significant cause of morbidity; it is a priority for vaccine development. A controlled human infection model for Schistosoma mansoni (CHI-S) with potential to accelerate vaccine development has been developed among naïve volunteers in the Netherlands. Because responses both to infections and candidate vaccines are likely to differ between endemic and non-endemic settings, we propose to establish a CHI-S in Uganda where Schistosoma mansoni is endemic. As part of a “road-map” to this goal, we have undertaken a risk assessment. We identified risks related to importing of laboratory vector snails and schistosome strains from the Netherlands to Uganda; exposure to natural infection in endemic settings concurrently with CHI-S studies, and unfamiliarity of the community with the nature, risks and rationale for CHI. Mitigating strategies are proposed. With careful implementation of the latter, we believe that CHI-S can be implemented safely in Uganda. Our reflections are presented here to promote feedback and discussion.Item Safety and immunogenicity of ChAdOx1 85A prime followed by MVA85A boost compared with BCG revaccination among Ugandan adolescents who received BCG at birth: a randomised, open-label trial(Elsevier Ltd, 2024-03) Wajja, Anne; Nassanga, Beatrice; Natukunda, Agnes; Serubanja, Joel; Tumusiime, Josephine; Akurut, Helen; Oduru, Gloria; Nassuuna, Jacent; Kabagenyi, Joyce; Morrison, Hazel; Scott, Hannah; Doherty, Rebecca Powell; Marshall, Julia L; Puig, Ingrid Cabrera; Cose, Stephen; Kaleebu, Pontiano; Webb, Emily L; Satti, Iman; McShane, Helen; Elliott, Alison M; Namutebi, Milly; Nakazibwe, Esther; Onen, Caroline; Apuule, Barbara; Akello, Florence; Mukasa, Mike; Nnaluwooza, Marble; Sewankambo, Moses; Kiwanuka, Sam; Kiwudhu, Fred; Imede, Esther; Nkurunungi, Gyaviira; Nakawungu, Prossy Kabuubi; Kabami, Grace; Nuwagaba, Emmanuel; Akello, MirriamAbstract BACKGROUNDBCG confers reduced, variable protection against pulmonary tuberculosis. A more effective vaccine is needed. We evaluated the safety and immunogenicity of candidate regimen ChAdOx1 85A-MVA85A compared with BCG revaccination among Ugandan adolescents.METHODSAfter ChAdOx1 85A dose escalation and age de-escalation, we did a randomised open-label phase 2a trial among healthy adolescents aged 12-17 years, who were BCG vaccinated at birth, without evident tuberculosis exposure, in Entebbe, Uganda. Participants were randomly assigned (1:1) using a block size of 6, to ChAdOx1 85A followed by MVA85A (on day 56) or BCG (Moscow strain). Laboratory staff were masked to group assignment. Primary outcomes were solicited and unsolicited adverse events (AEs) up to day 28 and serious adverse events (SAEs) throughout the trial; and IFN-γ ELISpot response to antigen 85A (day 63 [geometric mean] and days 0-224 [area under the curve; AUC).FINDINGSSix adults (group 1, n=3; group 2, n=3) and six adolescents (group 3, n=3; group 4, n=3) were enrolled in the ChAdOx1 85A-only dose-escalation and age de-escalation studies (July to August, 2019). In the phase 2a trial, 60 adolescents were randomly assigned to ChAdOx1 85A-MVA85A (group 5, n=30) or BCG (group 6, n=30; December, 2019, to October, 2020). All 60 participants from groups 5 and 6 were included in the safety analysis, with 28 of 30 from group 5 (ChAdOx1 85A-MVA85A) and 29 of 30 from group 6 (BCG revaccination) analysed for immunogenicity outcomes. In the randomised trial, 60 AEs were reported among 23 (77%) of 30 participants following ChAdOx1 85A-MVA85A, 31 were systemic, with one severe event that occurred after the MVA85A boost that was rapidly self-limiting. All 30 participants in the BCG revaccination group reported at least one mild to moderate solicited AE; most were local reactions. There were no SAEs in either group. Ag85A-specific IFN-γ ELISpot responses peaked on day 63 in the ChAdOx1 85A-MVA85A group and were higher in the ChAdOx1 85A-MVA85A group compared with the BCG revaccination group (geometric mean ratio 30·59 [95% CI 17·46-53·59], p<0·0001, day 63; AUC mean difference 57 091 [95% CI 40 524-73 658], p<0·0001, days 0-224).INTERPRETATIONThe ChAdOx1 85A-MVA85A regimen was safe and induced stronger Ag85A-specific responses than BCG revaccination. Our findings support further development of booster tuberculosis vaccines.FUNDINGUK Research and Innovations and Medical Research Council.TRANSLATIONSFor the Swahili and Luganda translations of the abstract see Supplementary Materials section.Item Schistosoma mansoni coinfection is associated with high Plasmodium falciparum infection intensity among 10 -15 year old children living along the Albert Nile in Uganda(Research Sqaure, 2024) Namulondo, Joyce; Nyangiri, Oscar Asanya; Kimuda, Magambo Phillip; Nambala, Peter; Nassuuna, Jacent; Kabagenyi, Joyce; Egesa, Moses; Nerima, Barbara; Biryomumaisho, Savino; Mugasa, Claire Mack; Alison, Elliott; Harry, Noyes; Tweyongyere, Robert; Matovu, Enock; Mulindwa, JuliusBackground: Malaria and schistosomiasis are important parasitic diseases. Coinfections of these have been reported in areas endemic to both parasites. The aim of this study was to determine the association between Schistosoma mansoni (S. mansoni) and Plasmodium falciparum (P. falciparum) infection intensities among school age children living along the Albert Nile. Methods: A cross sectional study of 210 children aged 10–15 years, was conducted in selected sites along the Albert Nile in Pakwach District in northwest Uganda. The Circulating Anodic Antigen (CAA) test and quantitative PCR (qPCR) were used to test for S. mansoni infection intensity and quantitative PCR used to test for P. falciparum infection intensity. Results: Of the 210 study particpants, 76.2% (160/210) were malaria positive whereas 91% (191/210) were S. mansoni positive. There were only 1% (3/210) infections of each of Necator americanus and Strongyloides stercolaris. Of the P. falciparum positive children 57.5% (92/160) were male; on the other hand 53.4% (102/191) of the S. mansoni positive children were male. Overall, 150 of the 210 children tested (71%) had co-infection with both P. falciparum and S. mansoni. There was a significant association (p-value = 7.306e-10, r2 = 0.17) between P. falciparum qPCR Ct-value and S. mansoni qPCR Ct-value. There was a significant association (p-value = 7.306e-10, r2 = 0.17) between P. falciparum intensity (qPCR Ct-value) and S. mansoni intensity (qPCR Ct-value) among the children test. Conclusions: By molecular detection, this study observed a high prevalence of P. falciparum among the school age children (10–15 years) living in the S. mansoni endemic hotspots along the Albert-Nile region of Pakwach district, northwestern Uganda.Item Transcriptome analysis of peripheral blood of Schistosoma mansoni infected children from the Albert Nile region in Uganda reveals genes implicated in fibrosis pathology(PLOS NEGLECTED TROPICAL DISEASES, 2023) Namulondo, Joyce; Nyangiri, Oscar Asanya; Kimuda, Magambo Phillip; Nambala, Peter; Nassuuna, Jacent; Egesa, Moses; Nerima, Barbara; Biryomumaisho, Savino; Mugasa, Claire Mack; Nabukenya, Immaculate; Kato, Drago; Alison, Elliott; Harry, Noye; Tweyongyere, Robert; Matovu, Enock; Mulindwa, JuliusOver 290 million people are infected by schistosomes worldwide. Schistosomiasis control efforts focus on mass drug treatment with praziquantel (PZQ), a drug that kills the adult worm of all Schistosoma species. Nonetheless, re-infections have continued to be detected in endemic areas with individuals living in the same area presenting with varying infection intensities. Our objective was to characterize the transcriptome profiles in peripheral blood of children between 10–15 years with varying intensities of Schistosoma mansoni infection living along the Albert Nile in Uganda. RNA extracted from peripheral blood collected from 44 S. mansoni infected (34 high and 10 low by circulating anodic antigen [CAA] level) and 20 uninfected children was sequenced using Illumina NovaSeq S4 and the reads aligned to the GRCh38 human genome. Differential gene expression analysis was done using DESeq2. Principal component analysis revealed clustering of gene expression by gender when S. mansoni infected children were compared with uninfected children. In addition, we identified 14 DEGs between S. mansoni infected and uninfected individuals, 56 DEGs between children with high infection intensity and uninfected individuals, 33 DEGs between those with high infection intensity and low infection intensity and no DEGs between those with low infection and uninfected individuals. We also observed upregulation and downregulation of some DEGs that are associated with fibrosis and its regulation. These data suggest expression of fibrosis associated genes as well as genes that regulate fibrosis in S. mansoni infection. The relatively few significant DEGS observed in children with schistosomiasis suggests that chronic S. mansoni infection is a stealth infection that does not stimulate a strong immune response.Item Transcriptome analysis of peripheral blood of Schistosoma Mansoni Infected Children from the Albert Nile Region in Uganda Reveals Genes Implicated in Fibrosis Pathology.(bioRxiv, 2023) Namulondo, Joyce; Nyangiri, Oscar Asanya; Kimuda, Magambo Phillip; Nambala, Peter; Nassuuna, Jacent; Egesa, Moses; Nerima, Barbara; Biryomumaisho, Savino; Nabukenya, Immaculate; Drago, Kato; Tweyongyere, Robert; Matovu, Enock; Mulindwa, Julius; Mugasa, Claire MackOver 290 million people are infected by schistosomes worldwide. Schistosomiasis control efforts focus on mass drug treatment with praziquantel (PZQ), a drug that kills the adult worm of all Schistosoma species. Nonetheless, re-infections have continued to be detected in endemic areas with individuals living in the same area presenting with varying infection intensities. Our objective was to characterize the transcriptome profiles in peripheral blood of children between 10 - 15 years with varying intensities of Schistosoma mansoni infection living along the Albert Nile in Uganda. RNA extracted from peripheral blood collected from 44 S. mansoni infected (34 high and 10 low by circulating anodic antigen [CAA] level) and 20 uninfected children was sequenced using Illumina NovaSeq S4 and the reads aligned to the GRCh38 human genome. Differential gene expression analysis was done using DESeq2 and enriched pathways in differentially expressed genes (DEGs) were identified using REACTOME. Principal component analysis revealed clustering of gene expression by gender when S. mansoni infected children were compared with uninfected children. In addition, we identified 14 DEGs between S. mansoni infected and uninfected individuals, 56 DEGs between children with high infection intensity and uninfected individuals, 33 DEGs between those with high infection intensity and low infection intensity and no DEGs between those with low infection and uninfected individuals. We also observed upregulation and downregulation of some DEGs that are associated with fibrosis and its regulation. These data suggest expression of fibrosis associated genes as well as genes that regulate fibrosis in S. mansoni infection. The relatively few significant DEGS observed in children with schistosomiasis suggests that chronic S. mansoni infection is a stealth infection that does not stimulate a strong immune response.Item Transcriptome profiling reveals genes associated with inflammation and fibrosis among 10 - 15-yearold children with Schistosoma mansoni and Plasmodium falciparum coinfection along the Albert Nile in Uganda(Research Square, 2024) Namulondo, Joyce; Nyangiri Oscar Asanya; Nyangiri, Magambo Phillip Kimuda; Nambala, Peter; Nassuuna, Jacent; Kabagenyi, Joyce; Egesa, Moses; Nerima, Barbara; Biryomumaisho, Savino; Mugasa, Claire Mack; Harry, Noyes; Tweyongyere, Robert; Matovu, Enock; Mulindwa, JuliusBackground: Malaria and schistosomiasis are significant parasitic diseases in Uganda and coinfections with the two are not uncommon in areas endemic to both parasites. The aim of this study was to determine the effect of P. falciparum and S. mansoni coinfection on the gene expression in peripheral blood of school age children aged between 10–15 years. Methods: A cross sectional study of children aged 10–15 years, was conducted in selected sites along the Albert Nile in Pakwach District in northwest Uganda. Quantitative PCR (qPCR) was used to test for S. mansoni and P. falciparum infection. Furthermore samples that were sequenced using Illumina NovaSeq S4 and the reads aligned to the GRCh38 human genome were matched with those with S. mansoni and P. falciparum qPCR results. Differential gene expression analysis was done using DESeq2. Results: Of the 210 study particpants, 76.2% (160/210) were P. falciparum positive, 91% (191/210) were S. mansoni positive and 150 (71%) had coinfection with both P. falciparum and S. mansoni, which was slightly fewer coinfections than expected by chance (Fisher exact test p-value of 0.02). RNAseq data was obtained for 33 participants of which 17 had P. falciparum and S. mansoni coinfection, 4 S. mansoni infection only, 1 had P. falciparum infection only while 11 were uninfected. Principal component analysis revealed clustering of gene expression by gender and infection status when S. mansoni and P. falciparum coinfected children were compared with uninfected children. We observed 15 DEGs of which 2 (CEPT1 and RETREG1) were downregulated and 13 (GAS6, DEXI, PALMD, SAMD15 AC138028.4, GFOD1-AS1, AC034102.6, AC005153.1, AC020914.1, AC017028.2, AC244502.3, AC013486.1, AC106760.1) upregulated when S. mansoni and P. falciparum coinfected children were compared with uninfected children. The differentially expressed genes are associated with inflammation and fibrosis and also included regulatory long noncoding RNA. Conclusions: By molecular detection, this study observed a high prevalence of P. falciparum among the school age children (10–15 years) living in the S. mansoni endemic hotspots along the Albert-Nile region of Pakwach district, northwestern Uganda. The study shows differential expression of genes associated with inflammation and fibrosis among coinfected when compared to the uninfected children.Item Variants of IL6, IL10, FCN2, RNASE3, IL12B and IL17B loci are associated with Schistosoma mansoni worm burden in the Albert Nile region of Uganda(PLOS NEGLECTED TROPICAL DISEASES, 2023) Nyangiri, Oscar Asanya; Mulindwa, Julius; Namulondo, Joyce; Kitibwa, Anna; Nassuuna, Jacent; Alison, Elliott; Kimuda, Magambo Phillip; Boobo, Alex; Nerima, Barbara; Adriko, Moses; Nathan, J. Dunton; Gaganjit, Kaur Madhan; Mark, Kristiansen; Miriam, Casacuberta-Partal; Harry, Noyes; Matovu, EnockBackground Individuals genetically susceptible to high schistosomiasis worm burden may contribute disproportionately to transmission and could be prioritized for control. Identifying genes involved may guide development of therapy. Methodology/Principal findings A cohort of 606 children aged 10–15 years were recruited in the Albert Nile region of Uganda and assessed for Schistosoma mansoni worm burden using the Up-Converting Particle Lateral Flow (UCP-LF) test detecting circulating anodic antigen (CAA), point-of-care Circulating Cathodic Antigen (POC-CCA) and Kato-Katz tests. Whole genome genotyping was conducted on 326 children comprising the top and bottom 25% of worm burden. Linear models were fitted to identify variants associated with worm burden in preselected candidate genes. Expression quantitative trait locus (eQTL) analysis was conducted for candidate genes with UCP-LF worm burden included as a covariate. Single Nucleotide Polymorphism loci associated with UCP-LF CAA included IL6 rs2066992 (OR = 0.43, p = 0.0006) and rs7793163 (OR = 2.0, p = 0.0007); IL21 SNP kgp513476 (OR 1.79, p = 0.0025) and IL17B SNP kgp708159 (OR = 0.35, p = 0.0028). A haplotype in the IL10 locus was associated with lower worm burden (OR = 0.53, p = 0.015) and overlapped SNPs rs1800896, rs1800871 and rs1800872. Significant haplotypes (p<0.05, overlapping significant SNP) associated with worm burden were observed in IL6 and the Th17 pathway IL12B and IL17B genes. There were significant eQTL in the IL6, IL5, IL21, IL25 and IFNG regions. Conclusions Variants associated with S. mansoni worm burden were in IL6, FCN2, RNASE3, IL10, IL12B and IL17B gene loci. However only eQTL associations remained significant after Bonferroni correction. In summary, immune balance, pathogen recognition and Th17 pathways may play a role in modulating Schistosoma worm burden. Individuals carrying risk variants may be targeted first in allocation of control efforts to reduce the burden of schistosomiasis in the community.