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1.
bioRxiv ; 2024 Jun 29.
Article in English | MEDLINE | ID: mdl-38979184

ABSTRACT

Background: Parasitic flatworms of the Schistosoma genus cause schistosomiasis, which affects over 230 million people. Schistosoma haematobium causes the urogenital form of schistosomiasis (UGS), which can lead to hematuria, fibrosis, and increased risk of secondary infections by bacteria or viruses. UGS is also linked to bladder cancer. To understand the bladder pathology during S. haematobium infection, our group previously developed a mouse model that involves the injection of S. haematobium eggs into the bladder wall. Using this model, we studied changes in epigenetics profile, as well as changes in gene and protein expression in the host bladder tissues. In the current study, we expand upon this work by examining the expression level of both host and parasite genes using RNA sequencing (RNA-seq) in the mouse bladder wall injection model of S. haematobium infection. Methods: We used a mouse model of S. haematobium infection in which parasite eggs or vehicle control were injected into the bladder walls of female BALB/c mice. RNA-seq was performed on the RNA isolated from the bladders four days after bladder wall injection. Results/Conclusions: RNA-seq analysis of egg- and vehicle control-injected bladders revealed the differential expression of 1025 mouse genes in the egg-injected bladders, including genes associated with cellular infiltration, immune cell chemotaxis, cytokine signaling, and inflammation We also observed the upregulation of immune checkpoint-related genes, which suggests that while the infection causes an inflammatory response, it also dampens the response to avoid excessive inflammation-related damage to the host. Identifying these changes in host signaling and immune responses improves our understanding of the infection and how it may contribute to the development of bladder cancer. Analysis of the differential gene expression of the parasite eggs between bladder-injected versus uninjected eggs revealed 119 S. haematobium genes associated with transcription, intracellular signaling, and metabolism. The analysis of the parasite genes also revealed fewer transcript reads compared to that found in the analysis of mouse genes, highlighting the challenges of studying parasite egg biology in the mouse model of S. haematobium infection. Author summary: More than 230 million people worldwide are estimated to carry infection with parasites belonging to the Schistosoma genus, which cause morbidity associated with parasite egg deposition. Praziquantel, the drug of choice to treat the infection, does not prevent reinfection, and its decades-long history as the main treatment raises concerns for drug resistance. Of the schistosome species, Schistosoma haematobium causes urogenital disease and has a strong association with bladder cancer. The possibility for drug resistance and the gap in knowledge with respect to the mechanisms driving S. haematobium -related bladder cancer highlight the need to better understand the biology of the infection to aid in the development of new therapeutic strategies. In this study, we used a mouse model of S. haematobium infection that delivers parasite eggs directly to the host mouse bladder wall, and we examined the changes in the gene expression profile of the host and the parasite by RNA-sequencing. The results corroborated previous findings with respect to the host's inflammatory responses against the parasite eggs, as well as revealed alterations in other immune response genes that deepen our understanding of the mechanisms involved in urogenital schistosomiasis pathogenesis.

2.
PLoS Negl Trop Dis ; 16(2): e0010176, 2022 02.
Article in English | MEDLINE | ID: mdl-35167594

ABSTRACT

Urogenital schistosomiasis remains a major public health concern worldwide. In response to egg deposition, the host bladder undergoes gross and molecular morphological changes relevant for disease manifestation. However, limited mechanistic studies to date imply that the molecular mechanisms underlying pathology are not well-defined. We leveraged a mouse model of urogenital schistosomiasis to perform for the first time, proteome profiling of the early molecular events that occur in the bladder after exposure to S. haematobium eggs, and to elucidate the protein pathways involved in urogenital schistosomiasis-induced pathology. Purified S. haematobium eggs or control vehicle were microinjected into the bladder walls of mice. Mice were sacrificed seven days post-injection and bladder proteins isolated and processed for proteome profiling using mass spectrometry. We demonstrate that biological processes including carcinogenesis, immune and inflammatory responses, increased protein translation or turnover, oxidative stress responses, reduced cell adhesion and epithelial barrier integrity, and increased glucose metabolism were significantly enriched in S. haematobium infection. S. haematobium egg deposition in the bladder results in significant changes in proteins and pathways that play a role in pathology. Our findings highlight the potential bladder protein indicators for host-parasite interplay and provide new insights into the complex dynamics of pathology and characteristic bladder tissue changes in urogenital schistosomiasis. The findings will be relevant for development of improved interventions for disease control.


Subject(s)
Host-Parasite Interactions/physiology , Schistosoma haematobium/pathogenicity , Schistosomiasis haematobia/physiopathology , Urinary Bladder/parasitology , Animals , Disease Models, Animal , Female , Mice, Inbred BALB C , Ovum , Proteome , Urinary Bladder/metabolism , Urinary Bladder/pathology
3.
PLoS Negl Trop Dis ; 14(12): e0008866, 2020 12.
Article in English | MEDLINE | ID: mdl-33315875

ABSTRACT

Helminths are parasitic worms that infect over a billion people worldwide. The pathological consequences from infection are due in part, to parasite-induced changes in host metabolic pathways. Here, we analyse the changes in host metabolic profiles, in response to the first Schistosoma haematobium infection and treatment in Zimbabwean children. A cohort of 83 schistosome-negative children (2-5 years old) as determined by parasitological examination, guardian interviews and examination of medical records, was recruited at baseline. Children were followed up after three months for parasitological diagnosis of their first S. haematobium infection, by detection of parasite eggs excreted in urine. Children positive for infection were treated with the antihelminthic drug praziquantel, and treatment efficacy checked three months after treatment. Blood samples were taken at each time point, and capillary electrophoresis mass spectrometry in conjunction with multivariate analysis were used to compare the change in serum metabolite profiles in schistosome-infected versus uninfected children. Following baseline at the three-month follow up, 11 children had become infected with S. haematobium (incidence = 13.3%). Our results showed that infection with S. haematobium was associated with significant increases (>2-fold) in discriminatory metabolites, linked primarily with energy (G6P, 3-PG, AMP, ADP) and purine (AMP, ADP) metabolism. These observed changes were commensurate with schistosome infection intensity, and levels of the affected metabolites were reduced following treatment, albeit not significantly. This study demonstrates that early infection with S. haematobium is associated with alterations in host energy and purine metabolism. Taken together, these changes are consistent with parasite-related clinical manifestations of malnutrition, poor growth and poor physical and cognitive performance observed in schistosome-infected children.


Subject(s)
Energy Metabolism , Purines/metabolism , Schistosoma haematobium , Schistosomiasis haematobia/drug therapy , Schistosomiasis haematobia/metabolism , Animals , Anthelmintics/therapeutic use , Child, Preschool , Female , Humans , Male , Praziquantel/therapeutic use
4.
PLoS Negl Trop Dis ; 14(10): e0008650, 2020 10.
Article in English | MEDLINE | ID: mdl-33001969

ABSTRACT

In 2012, the World Health Organisation (WHO) set out a roadmap for eliminating schistosomiasis as a public health problem by 2025. To achieve this target, preschool-aged children (PSAC; aged 6 years and below) will need to be included in schistosomiasis treatment programmes. As the global community discusses the tools and approaches for treating this group, one of the main questions that remains unanswered is how to quantify infection in this age group to inform treatment strategies. The aim of this study was thus to determine whether a relationship exists between levels of schistosome infection in PSAC and school-aged children (SAC), that can be used to determine unknown schistosome infection prevalence levels in PSAC. A systematic search of publications reporting schistosomiasis prevalence in African PSAC and SAC was conducted. The search strategy was formulated using the PRISMA guidelines and SPIDER search strategy tool. The published data was subjected to regression analysis to determine if a relationship exists between infection levels in PSAC and SAC. The interaction between SAC and community treatment history was also entered in the regression model to determine if treatment history significantly affected the relationship between PSAC and SAC prevalence. The results showed that a significant positive relationship exists between infection prevalence levels in PSAC and SAC for Schistosoma mansoni (r = 0.812, df (88, 1), p = <0.0001) and S. haematobium (r = 0.786, df (53, 1), p = <0.0001). The relationship was still significant after allowing for diagnostic method, treatment history, and the African sub-region where the study was conducted (S. mansoni: F = 25.63, df (88, 9), p = <0.0001; S. haematobium: F = 10.20, df (53, 10), p = <0.0001). Using the regression equation for PSAC and SAC prevalence, over 90% of the PSAC prevalence studies were placed in the correct WHO classifications category based on the SAC levels, regardless of treatment history. The study indicated that schistosome prevalence in SAC can be extended as a proxy for infection levels in PSAC, extending on its current use in the adult population. SAC prevalence data could identify where there is a need to accelerate and facilitate the treatment of PSAC for schistosomiasis in Africa.


Subject(s)
Schistosoma haematobium , Schistosoma mansoni , Schistosomiasis/epidemiology , Adolescent , Africa/epidemiology , Animals , Child , Child, Preschool , Humans , Models, Statistical , Prevalence , Schistosomiasis/parasitology
5.
PLoS Negl Trop Dis ; 14(6): e0008388, 2020 06.
Article in English | MEDLINE | ID: mdl-32569278

ABSTRACT

BACKGROUND: The World Health Organization recommends that schistosomiasis be treated through Mass Drug Administration (MDA). In line with this recommendation, Zimbabwe commenced a national helminth control program in 2012 targeting schoolchildren throughout the country for 6 years. This study, part of a larger investigation of the impact of helminth treatment on the overall health of the children, determined the effect of annual praziquantel treatment on schistosome infection and morbidity in a cohort of children during Zimbabwe's 6-year national helminth control program. METHODOLOGY/PRINCIPAL FINDINGS: A school-based longitudinal study was carried out in 35 sentinel sites across Zimbabwe from September 2012 to November 2017. The sentinel sites were selected following a countrywide survey conducted in 280 primary schools. Schistosoma haematobium was diagnosed using the urine filtration technique. Schistosoma mansoni was diagnosed using both the Kato-Katz and formol-ether concentration techniques. S. haematobium morbidity was determined through detection of macro and microhaematuria. A cohort of children aged 6-15 years old was surveyed annually before MDA and 6 weeks post treatment. Maximum treatment coverage reached 90% over the 6 rounds of MDA. At baseline S. haematobium infection prevalence and intensity were 31.7% (95% CI = 31.1-32.2) and 28.75 eggs/10ml urine (SEM = 0.81) respectively, while S. mansoni prevalence and intensity were 4.6% (95% CI = 4.4-4.8) and 0.28 eggs/25mg (SEM = 0.02). Prior to the 6th round of MDA, S. haematobium infection prevalence had reduced to 1.56% (p<0.001) and infection intensity to 0.07 (SEM 0.02). Six weeks later after the 6th MDA, both were 0. Similarly the prevalence of S. haematobium morbidity as indicated by haematuria also fell significantly from 32.3% (95% CI = 29.9-34.6) to 0% (p< 0.0001) prior to the final MDA. For S.mansoni, both prevalence and intensity had decreased to 0 prior to the 6th MDA. After 6 rounds of annual MDA, prevalence and intensity of both schistosome species decreased significantly to 0% (p< 0.0001). CONCLUSION: Zimbabwe's helminth control program significantly reduced schistosome infection intensity and prevalence and urogenital schistosomiasis morbidity prevalence in a cohort of school-aged children, moving the schistosome prevalence in the children from moderate to low by WHO classification. These findings will inform the design of the country's next stage interventions for helminth control and eventual elimination.


Subject(s)
Helminthiasis/drug therapy , Mass Drug Administration/methods , Praziquantel/therapeutic use , Trematode Infections/drug therapy , Adolescent , Animals , Child , Cohort Studies , Cross-Sectional Studies , Female , Helminthiasis/diagnosis , Helminthiasis/epidemiology , Helminths/isolation & purification , Hematuria , Humans , Longitudinal Studies , Male , Morbidity , Prevalence , Schistosoma haematobium , Schistosoma mansoni , Schistosomatidae/isolation & purification , Schistosomiasis haematobia/drug therapy , Schools , Surveys and Questionnaires , Trematode Infections/diagnosis , Trematode Infections/epidemiology , Zimbabwe/epidemiology
6.
Trends Parasitol ; 36(7): 582-591, 2020 07.
Article in English | MEDLINE | ID: mdl-32430274

ABSTRACT

Despite accelerating progress towards schistosomiasis control in sub-Saharan Africa, several age groups have been eclipsed by current treatment and monitoring strategies that mainly focus on school-aged children. As schistosomiasis poses a threat to people of all ages, unfortunate gaps exist in current treatment coverage and associated monitoring efforts, preventing subsequent health benefits to preschool-aged children as well as certain adolescents and adults. Expanding access to younger ages through the forthcoming pediatric praziquantel formulation and improving treatment coverage in older ages is essential. This should occur alongside formal inclusion of these groups in large-scale monitoring and evaluation activities. Current omission of these age groups from treatment and monitoring exacerbates health inequities and has long-term consequences for sustainable schistosomiasis control.


Subject(s)
Schistosomiasis/epidemiology , Schistosomiasis/prevention & control , Africa South of the Sahara/epidemiology , Age Distribution , Anthelmintics/therapeutic use , Humans , Schistosomiasis/drug therapy
7.
Commun Biol ; 3(1): 155, 2020 04 02.
Article in English | MEDLINE | ID: mdl-32242065

ABSTRACT

Helminth parasites have been shown to have systemic effects in the host. Using shotgun metagenomic sequencing, we characterise the gut microbiome and resistome of 113 Zimbabwean preschool-aged children (1-5 years). We test the hypothesis that infection with the human helminth parasite, Schistosoma haematobium, is associated with changes in gut microbial and antimicrobial resistance gene abundance/diversity. Here, we show that bacteria phyla Bacteroidetes, Firmicutes, Proteobacteria, and fungi phyla Ascomycota, Microsporidia, Zoopagomycota dominate the microbiome. The abundance of Proteobacteria, Ascomycota, and Basidiomycota differ between schistosome-infected versus uninfected children. Specifically, infection is associated with increases in Pseudomonas, Stenotrophomonas, Derxia, Thalassospira, Aspergillus, Tricholoma, and Periglandula, with a decrease in Azospirillum. We find 262 AMR genes, from 12 functional drug classes, but no association with individual-specific data. To our knowledge, we describe a novel metagenomic dataset of Zimbabwean preschool-aged children, indicating an association between urogenital schistosome infection and changes in the gut microbiome.


Subject(s)
Bacteria/growth & development , Gastrointestinal Microbiome , Intestines/microbiology , Schistosoma haematobium/pathogenicity , Schistosomiasis haematobia/microbiology , Schistosomiasis haematobia/parasitology , Age Factors , Animals , Bacteria/classification , Bacteria/genetics , Case-Control Studies , Child, Preschool , Cross-Sectional Studies , Female , Host-Parasite Interactions , Humans , Infant , Male , Metagenome , Metagenomics , Schistosomiasis haematobia/diagnosis , Zimbabwe
8.
BMC Infect Dis ; 19(1): 1071, 2019 Dec 19.
Article in English | MEDLINE | ID: mdl-31856765

ABSTRACT

BACKGROUND: Schistosomiasis is known to induce inflammatory immune responses. C-reactive protein (CRP), resistin and P-selectin are serological inflammatory markers that rise during the acute stages of infection. Here, we propose such inflammatory biomarkers have a potential for use in urogenital schistosomiasis diagnostic screening for exposure and infection in preschool-aged children. METHODS: As part of a larger study on urogenital schistosomiasis, 299 preschool children aged 1-5 years were included in this cross-sectional study. Parasitological diagnosis was conducted using urine filtration for Schistosoma haemtobium infection, and Kato Katz for S. mansoni infection. Serum levels of P-selectin, resistin, CRP, and antibodies against S. haematobium cercarial antigen preparation (CAP) and soluble worm antigen preparation (SWAP) were measured by ELISA. RESULTS: Of the 299 participants, 14% were egg positive for S. haematobium. Serology showed 46 and 9% of the participants to have been exposed to S. haematobium cercarial antigens and adult worm antigens, respectively. Levels of P-selectin were significantly higher in participants infected with S. haematobium (egg-positive) than in uninfected participants (p = 0.001). Levels of P-selectin were also higher in those exposed to cercarial antigen than in unexposed participants (p = 0.019). There was a positive correlation between P-selectin and infection intensity (r = 0.172; p = 0.002), as well as with IgM responses to CAP and SWAP (r = 0.183; p = 0.001); (r = 0.333; p < 0.0001) respectively. CRP significantly correlated with IgM responses to CAP (r = 0.133; p = 0.029) while resistin correlated with IgM responses to CAP and SWAP (r = 0.127; p = 0.016); (r = 0.197; p = 0.0004). CRP levels were higher in those exposed to cercarial and adult worm antigens than unexposed participants (p = 0.035); (p = 0.002) respectively, while resistin was higher in participants exposed to cercarial antigen than unexposed participants (p = 0.024). CONCLUSION: In this preschool population, P-selectin is significantly associated with urogenital schistosome infection and intensity; hence a potential biomarker for infection diagnosis and disease monitoring. The inflammatory biomarkers (P-selectin, Resistin and CRP) were significantly higher in participants exposed to cercarial antigens than unexposed individuals indicating an underlying inflammatory environment.


Subject(s)
Antigens, Helminth/immunology , C-Reactive Protein/analysis , Female Urogenital Diseases/parasitology , Male Urogenital Diseases/parasitology , P-Selectin/analysis , Resistin/analysis , Schistosomiasis haematobia/diagnosis , Schistosomiasis mansoni/diagnosis , Animals , Biomarkers/analysis , Child, Preschool , Cross-Sectional Studies , Diagnostic Tests, Routine , Enzyme-Linked Immunosorbent Assay , Female , Humans , Infant , Longitudinal Studies , Male , Schistosoma haematobium/immunology , Schistosoma mansoni/immunology , Schistosomiasis haematobia/parasitology , Schistosomiasis mansoni/parasitology
9.
PLoS Negl Trop Dis ; 12(2): e0006144, 2018 02.
Article in English | MEDLINE | ID: mdl-29420537

ABSTRACT

Schistosomiasis affects over 200 million people worldwide, most of whom are children. Research and control strategies directed at preschool-aged children (PSAC), i.e., ≤5 years old, have lagged behind those in older children and adults. With the recent WHO revision of the schistosomiasis treatment guidelines to include PSAC, and the recognition of gaps in our current knowledge on the disease and its treatment in this age group, there is now a concerted effort to address these shortcomings. Global and national schistosome control strategies are yet to include PSAC in treatment schedules. Maximum impact of schistosome treatment programmes will be realised through effective treatment of PSAC. In this review, we (i) discuss the current knowledge on the dynamics and consequences of paediatric schistosomiasis and (ii) identify knowledge and policy gaps relevant to these areas and to the successful control of schistosome infection and disease in this age group. Herein, we highlight risk factors, immune mechanisms, pathology, and optimal timing for screening, diagnosis, and treatment of paediatric schistosomiasis. We also discuss the tools required for treating schistosomiasis in PSAC and strategies for accessing them for treatment.


Subject(s)
Schistosoma/pathogenicity , Schistosomiasis/diagnosis , Schistosomiasis/immunology , Schistosomiasis/therapy , Animals , Child , Child, Preschool , Humans , Immunity , Infection Control , Morbidity , Risk Factors , Schistosomiasis/epidemiology
10.
BMC Pregnancy Childbirth ; 16: 17, 2016 Jan 25.
Article in English | MEDLINE | ID: mdl-26810108

ABSTRACT

BACKGROUND: Postpartum haemorrhage (PPH) is the leading cause of maternal deaths, the world over. The aim of this study was to determine laboratory parameters that could serve as risk factors for primary PPH. METHODS: This comparative cohort study involved 350 pregnant women at term who were recruited consecutively from the Komfo Anokye Teaching Hospital, Kumasi, Ghana. PPH was defined as a measured blood loss ≥ 500 ml or enough to cause haemodynamic shock. Basic demographic data was gathered and blood was collected for laboratory assays before delivery. Univariate and multivariate logistic regression models were used to identify variables that were significantly associated with primary PPH. RESULTS: Of the total recruited study participants (350), five declined to participate and 74 went through caesarean section, episiotomy or instrumental deliveries and were excluded. Of the remaining (271) study participants who went through spontaneous vaginal delivery, fifty five (55) were diagnosed with primary PPH (Group 1) and the remaining 216 were those who did not have PPH (Group 2). Demographic characteristics did not differ between the two groups (P > 0.05). Univariate analysis showed that AST (P = 0.043), urea (P < 0.001), creatinine (P = 0.002), urea-to-creatinine ratio (P = 0.014) and the proportion of abnormal peripheral blood smear (P < 0.001) was higher among women in Group 1 compared to those in Group 2. Women in Group 1 had a significantly lower haemoglobin concentration (10.7 g/dL) compared to those in Group 2 (12.1g/dL). Upon multivariate analysis, an abnormal peripheral blood smear (AOR = 2.9672), Hb, (AOR = 0.5791), moderate to severe anaemia (Hb <10 g/dL) (AOR = 3.1385), Urea (AOR = 3.6435) and intra-renal azotaemia (AOR = 0.1893) remained significant. CONCLUSION: Many laboratory parameters are associated with primary PPH but only a few are independent risk factors. A total clinical work-up including laboratory evaluation of the independent blood variables identified in this study will help a great deal to identify individuals at high risk for PPH.


Subject(s)
Delivery, Obstetric/adverse effects , Peripartum Period/blood , Postpartum Hemorrhage/etiology , Adult , Alanine Transaminase/blood , Aspartate Aminotransferases/blood , Biomarkers/blood , Cohort Studies , Creatinine/blood , Female , Ghana , Hemoglobins/analysis , Humans , Logistic Models , Postpartum Hemorrhage/blood , Predictive Value of Tests , Pregnancy , Risk Factors , Urea/blood
11.
Niger Med J ; 55(6): 504-7, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25538371

ABSTRACT

BACKGROUND: Crystalluria is associated with some highly active anti-retroviral therapies (HAART's) used in the management of HIV/AIDS. AIMS: This study used light microscopy to establish the prevalence of crystalluria among HIV/AIDS patients on HAART and identified the routine crystals present in their urine. MATERIALS AND METHODS: In this simple randomised cross-sectional study, 200 HIV/AIDS participants, comprising 150 on HAART and 50 HAART-naïve were recruited from the HIV clinic at the Komfo Anokye Teaching Hospital (KATH). Urine and blood samples were collected, for urinalysis and the determination of the CD4 count, respectively. A well-structured pre-tested questionnaire was used to obtain socio-demographic data and clinical history of the participants. RESULTS: The prevalence of crystalluria was higher among HIV-infected persons on HAART than those not on HAART (6.7% vs 4%; P = 0.733). Calcium oxalate and triple phosphate crystals were the crystal types present in their urine (3.5% and 2.5%, respectively) and was present only in HIV subjects on first line of treatment (without protease inhibitors). Participants aged between 40-50 years and those with hypersthenuria and acidic urine had the highest amount of crystalluria (41.6%, 83.3%, and 58.3%, respectively). CONCLUSION: HAART is associated with crystalluria in HIV patients. Light microscopy will be of disgnostic value in resource limited settings.

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