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Cellular and chemokine-mediated regulation in schistosome-induced hepatic pathology

Chuah C, Jones MK, Burke ML, McManus DP, Gobert GN

Trends Parasitol, 2014 Mar;30(3):141-50.
PMID: 24433721 DOI: 10.1016/j.pt.2013.12.009

In hepatic schistosomiasis, pathology arises when schistosome eggs become lodged in the host liver, evoking an interleukin 4 (IL-4)- and IL-13-mediated dominant CD4(+) Th2 immune response. This response leads to the development of granulomas and fibrosis, with eosinophils, neutrophils, macrophages, hepatic stellate cells, and lymphocytes all identified as major cellular contributors to these events. This review outlines the cellular and molecular mechanisms of hepatic schistosomiasis, with an emphasis on the major cellular components and their release of chemokines. The differences between Schistosoma mansoni- and Schistosoma japonicum-induced hepatic granuloma are also discussed. This comprehensive overview of the processes associated with hepatic schistosomiasis may provide new insights into improved treatment for both schistosomiasis and other granulofibrotic diseases.

Matched MeSH terms: Schistosomiasis mansoni/complications; Schistosomiasis mansoni/immunology; Schistosomiasis mansoni/pathology
Fulltext Knowledge, attitude, and practices towards schistosomiasis among rural population in Yemen

Sady H, Al-Mekhlafi HM, Atroosh WM, Al-Delaimy AK, Nasr NA, Dawaki S, et al.

Parasit Vectors, 2015 Aug 25;8:436.
PMID: 26302747 DOI: 10.1186/s13071-015-1050-8

BACKGROUND: Schistosomiasis is highly prevalent in Yemen, with an estimated 3 million cases, particularly among rural communities. This community-based study aims to evaluate the knowledge, attitude and practices (KAP) on schistosomiasis among rural communities in Yemen.
METHODS: A cross-sectional study was carried out among 250 households from ten rural districts in Yemen. Overall, 400 children were screened for urogenital and intestinal schistosomiasis. Moreover, parents were interviewed using a pre-tested questionnaire to collect information about the demographic and socioeconomic information and their KAP concerning schistosomiasis.
RESULTS: A total of 127 (31.8%) children were found to be excreting schistosome eggs in either their urine or faeces (22.5% S. haematobium and 8.0% S. mansoni). Although 92.4% of the respondents had heard about schistosomiasis, 49.8%, 68.0% and 47.2% had knowledge concerning the transmission, signs and symptoms, and prevention, respectively. In addition, 77.1% considered schistosomiasis as harmful while 48.5% believed that schistosomiasis could be prevented, albeit their practices to prevent infections were still inadequate. Significant associations between the KAP and age, education, employment status and household monthly income were reported (P

Matched MeSH terms: Schistosomiasis mansoni/epidemiology; Schistosomiasis mansoni/parasitology; Schistosomiasis mansoni/prevention & control*; Schistosomiasis mansoni/urine
Immunogenicity, antibody responses and vaccine efficacy of recombinant annexin B30 against Schistosoma mansoni

Leow CY, Willis C, Chuah C, Leow CH, Jones M

Parasite Immunol., 2020 03;42(3):e12693.
PMID: 31880816 DOI: 10.1111/pim.12693

AIMS: Schistosomes infect approximately 250 million people worldwide. To date, there is no effective vaccine available for the prevention of schistosome infection in endemic regions. There remains a need to develop means to confer long-term protection of individuals against reinfection. In this study, an annexin, namely annexin B30, which is highly expressed in the tegument of Schistosoma mansoni was selected to evaluate its immunogenicity and protective efficacy in a mouse model.
METHODS AND RESULTS: Bioinformatics analysis showed that there were three potential linear B-cell epitopes and four conformational B-cell epitopes predicted from annexin B30, respectively. Full-length annexin B30 was cloned and expressed in Escherichia coli BL21(DE3). In the presence of adjuvants, the soluble recombinant protein was evaluated for its protective efficacy in two independent vaccine trials. Immunization of CBA mice with recombinant annexin B30 formulated either in alum only or alum/CpG induced a mixed Th1/Th2 cytokine profile but no significant protection against schistosome infection was detected.
CONCLUSION: Recombinant annexin B30 did not confer significant protection against the parasite. The molecule may not be suitable for vaccine development. However, it could be an ideal biomarker recommended for immunodiagnostics development.

Matched MeSH terms: Schistosomiasis mansoni/diagnosis; Schistosomiasis mansoni/immunology*
Fulltext Tropical gastrointestinal disease: hepatosplenic schistosomiasis--pathological, clinical and treatment review

Shekhar KC

Singapore Med J, 1994 Dec;35(6):616-21.
PMID: 7761889

S. mansoni and S. japonicum complex schistosomes cause hepatosplenic and hepatointestinal schistosomiasis. The prevalence and incidence of this disease is increasing in all the endemic areas. Hepatosplenic schistosomiasis is seen in a small subset of clinically infected patients and represents a good model of intrahepatic portal hypertension characterised by a presinusoidal portal block and a well preserved liver parenchyma. Symmers' fibrosis is seen in a significant proportion of patients with high worm load. While the pathogenesis of Symmers' pipe stem fibrosis has not been well established, experimental and clinical data point to egg induced granulomata. The main consequences are presinusoidal portal hypertension, oesophageal varices and hepatosplenomegaly. The most striking symptoms are haematemesis or melena secondary to variceal and gastrointestinal bleeding. Cofactors associated with the pathogenesis include aflatoxins, malnutrition, alcoholism, hepatitis B and C virus. While stool examination is the best technique for diagnosis, a number of immunological tests though sensitive are not specific. Ultrasonography is sensitive for detection of Symmer's fibrosis. Praziquantel and oxaminiquine are drugs found to be effective in the treatment of hepatosplenic schistosomiasis. Recently beta-blockers have been found to be effective in the treatment of gastrointestinal rebleeding. Endoscopic sclerotherapy has been found to be effective for treatment of bleeding oesophageal varices. The treatment of choice for portal hypertension is oesophagogastric devascularization with splenectomy (EGDS).

Matched MeSH terms: Schistosomiasis mansoni
Transcriptional profiling of the oesophageal gland region of male worms of Schistosoma mansoni

Nawaratna SS, Gobert GN, Willis C, Chuah C, McManus DP, Jones MK

Mol Biochem Parasitol, 2014 Sep;196(2):82-9.
PMID: 25149559 DOI: 10.1016/j.molbiopara.2014.08.002

The intestinal tract of schistosomes opens at the mouth and leads into the foregut or oesophageal region that is lined with syncytium continuous with the apical cytoplasm of the tegument. The oesophagus is surrounded by a specialised gland, the oesophageal gland. This gland releases materials into the lumen of the oesophagus and the region is thought to initiate the lysis of erythrocytes and neutralisation of immune effectors of the host. The oesophageal region is present in the early invasive schistosomulum, a stage potentially targetable by anti-schistosome vaccines. We used a 44k oligonucleotide microarray to identify highly up-regulated genes in microdissected frozen sections of the oesophageal gland of male worms of S. mansoni. We show that 122 genes were up-regulated 2-fold or higher in the oesophageal gland compared with a whole male worm tissue control. The enriched genes included several associated with lipid metabolism and transmembrane transport as well as some micro-exon genes. Since the oesophageal gland is important in the initiation of digestion and the fact that it develops early after invasion of the mammalian host, further study of selected highly up-regulated functionally important genes in this tissue may reveal new anti-schistosome intervention targets for schistosomiasis control.

Matched MeSH terms: Schistosomiasis mansoni/parasitology*
Multidisciplinary biomarkers aggrieve morbidity in schistosomiasis

Noha MA, Enas AE, Aly E, Mohamed AE

Trop Biomed, 2019 Dec 01;36(4):833-844.
PMID: 33597455

BACKGROUND: Biomarkers by definition are measurable molecules that mark the evidence of certain pathological processes. Collaboration of various biomarkers influences morbidity of schsitosomiasis in Egypt.
OBJECTIVES: To identify the biomarkers: CRP, IgE, hemoglobin, ferritin, vitamin D, and platelets in terms of relationship with active and chronic schistosomiasis; demographic data, and their interinfluence.
STUDY DESIGN: A cross-sectional study.
METHODS: Parasitological analysis of stool and urine samples, Indirect Hemagglutination Test, Enzyme linked Immunoassay, Hematology Analyzer, and Statistical Package SPSS (Statistical Package for the Social Sciences) version 25.
RESULTS: Out of 400 participants, 25% suffered of schistosomiasis: active S. mansoni infections in 7 cases (1.75%), S. haematobium infections in 6 cases (1.5%), and chronic schistosomiasis infections in 20 cases (5%). Creactive protein (CRP) likewise IgE levels were higher in active S. mansoni and S. haematobium infections when compared with chronic schistosomiasis. IgE levels appeared to affect infection intensity in S. haematobium. Inversely, hemoglobin (Hb) values were low in active schistosomiasis and upgraded in chronic infection (*p<0.05). Ferritin levels varied in active Schistosoma infection and normalized during chronicity. Vitamin D was reduced in active and chronic schistosomiais. Platelet counts were within normal ranges throughout the study groups. Distribution of ferritin, vit D, and platelets was statistically insignificant among Schistosoma infected population. Age affected only hemoglobin, CRP, and IgE biomarkers. CRP and IgE were in direct relationship together and inversely proportional with hemoglobin (*P <0.05).
CONCLUSION: Anemia increased proportionally with biomarkers of inflammatory stress (CRP and IgE) in early infections. Meanwhile, Hb and ferritin (iron stores) improved during chronicity. Hypovitaminosis-D associated the entire course of schistosomiasis while platelet counts were not affected.

Matched MeSH terms: Schistosomiasis mansoni/epidemiology*
Serine protease inhibitor, serpin, is a biomarker following Schistosoma mansoni re-infection in mice

Mohammed ES, El-Dakhly KM

Trop Biomed, 2021 Jun 01;38(2):63-67.
PMID: 33973574 DOI: 10.47665/tb.38.2.039

Schistosomiasis is a chronic parasitic disease affecting mostly low income and resourcelimited countries. Despite the distribution of the curative medicine, praziquantel (PZQ), the frequency of re-infection is commonly reported, thus, making a difficulty to discriminate treatment failure after re-infection. Therefore, assessing Schistosoma mansoni re-infection after praziquantel administration is crucial to prove the treatment efficacy and to break the transmission of infection in endemic areas. The evolution of highly sensitive and specific diagnostic markers, reliable to detect the re-infection and to evaluate the treatment efficacy, is required to control schistosomiasis. In this study, the potential role of serpin recombinant antigen of S. mansoni as a biomarker of re-infection and chemotherapeutic efficacy has been assessed. Therefore, 20 mice were experimentally challenged and re-challenged with 50 S. mansoni cercariae and divided into 4 equal groups; the first included infected mice (control positive), the second group was twice infected with S. mansoni and left untreated, the third included mice twice infected then treated with praziquantel following the last challenge, and the forth one remained uninfected and untreated (control negative). The current findings demonstrated that high levels of IgG and IgG1 bound to serpin were detected following the re-infection and rapidly declined post treatment. In summary, S. mansoni recombinant serpin could be used as a promising marker to discriminate S. mansoni re-infection and evaluated the efficacy of treatment. The translation of such a potential tool in endemic areas will provide a significant support for the elimination and control programs against schistosomiasis.

Matched MeSH terms: Schistosomiasis mansoni