Author Correction: Antigenic cross-reactivity between Schistosoma mansoni and allergenic invertebrates putatively due to shared glycanic epitopes

SUMMARYIn view of the known cross-reactivity of sera from patients with intestinal parasites to some Schistosoma mansoni antigens, field work was conducted in an area of Venezuela non-endemic for schistosomiasis using the routine immunoenzymatic assay (ELISA) with soluble egg antigen (SEA). False positive reactions represented 15·3% of the total population as determined by SEA–ELISA. SEA-immunoblotting of the false positive sera indicated that protein fractions of 91 and 80 kDa appear to be responsible for cross-reactivity. Sera from hookworm infected individuals produced a higher frequency and intensity of cross-reaction than other sera. SEA-fractions of 105, 54, 46, 42, 32, 25 and 15 kDa were the most specific.

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Immunocytochemical demonstration of a SALMFamide-like neuropeptide in the nervous system of adult and larval stages of the human blood fluke, Schistosoma mansoni

Parasitology ◽

10.1017/s0031182000063903 ◽

1995 ◽

Vol 110 (2) ◽

pp. 143-153 ◽

Cited By ~ 7

Author(s):

D. J. A. Brownlee ◽

I. Fairweather ◽

C. F. Johnston ◽

M. C. Thorndyke ◽

P. J. Skuce

Keyword(s):

Nervous System ◽

Schistosoma Mansoni ◽

Cross Reactivity ◽

Confocal Scanning Laser Microscopy ◽

Male Worm ◽

Male And Female ◽

Larval Stages ◽

Confocal Scanning ◽

Confocal Scanning Laser ◽

Nerve Cords

SUMMARYThe localization and distribution of SALMFamide immunoreactivity (IR), SI(GFNSALMFamide), in the nervous system of both the adult and larval stages of the trematode Schistosoma mansoni has been determined by an indirect immunofluorescent technique in conjunction with confocal scanning laser microscopy (CSLM). Immunostaining was widespread in the nervous system of adult male and female S. mansoni. In the central nervous system (CNS), IR was evident in nerve cells and fibres in the anterior ganglia, cerebral commissure and dorsal and ventral nerve cords. In the peripheral nervous system (PNS), IR was apparent in nerve plexuses associated with the subtegmental musculature, oral and ventral suckers, the lining of the gynaecophoric canal, and in fine nerve fibres innervating the dorsal tubercles of the male worm. In the reproductive system of male and female worms, Sl-IR was only observed around the ootype/Mehlis' gland complex in the female. Immunostaining was also evident in the nervous system of both miracidium and cercarial larval stages. A post-embedding, IgG-conjugated colloidal gold immunostaining technique was employed to examine the subcellular distribution of SALMFamide-IR in the CNS of S. mansoni. Gold labelling of peptide was localized over dense-cored vesicles within nerve cell bodies and fibres constituting the neuropile of the anterior ganglia, cerebral commissure and nerve cords of the CNS. Antigen pre-absorption studies indicated that the results obtained do suggest S1-like immunostaining and not cross-reactivity with other peptides, in particular FMRFamide.

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Molecular characterization of a partial sequence encoding a novel Schistosoma mansoni serine protease

Parasitology ◽

10.1017/s0031182097001546 ◽

1997 ◽

Vol 115 (4) ◽

pp. 395-402 ◽

Cited By ~ 6

Author(s):

C. COCUDE ◽

C. PIERROT ◽

C. CETRE ◽

C. GODIN ◽

A. CAPRON ◽

...

Keyword(s):

Schistosoma Mansoni ◽

Serine Protease ◽

Serine Proteases ◽

Mrna Level ◽

Cross Reactivity ◽

Reading Frame ◽

Consensus Sequences ◽

Degenerate Oligonucleotide ◽

Sequence Encoding

A PCR strategy using degenerate oligonucleotide primers based upon consensus sequences of the active site of serine proteases yielded a 467 bp fragment from genomic DNA from Schistosoma mansoni cercariae. The sequence presented a continuous open reading frame and the deduced amino acid sequence (156 aa) presented homologies with various serine proteases, in particular the highest percentage identity was observed with a mammalian plasma kallikrein. The expression of this serine protease was studied first at the mRNA level and it was only detected by RT-PCR in cercariae and in adult worms. At the protein level we were able to detect it by Western blotting and by using antigen extracts from metabolically radio-isotope labelled worms. The absence of any positive signal in Northern blot and the detection of the protein suggest that the mRNA has a very short half-life, however the protein may be accumulated in the parasite. The significance of identity with mammalian kallikrein was confirmed by cross-immunoreactivity with a native porcine pancreatic kallikrein. However, no cross-reactivity was observed with S. mansoni elastase, another serine protease. Thus, we suggest that the serine protease described in this paper is a kallikrein-like protease.

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ATP diphosphohydrolase from Schistosoma mansoni egg: characterization and immunocytochemical localization of a new antigen

Parasitology ◽

10.1017/s0031182004005244 ◽

2004 ◽

Vol 129 (1) ◽

pp. 51-57 ◽

Cited By ~ 23

Author(s):

P. FARIA-PINTO ◽

M. N. L. MEIRELLES ◽

H. L. LENZI ◽

E. M. MOTA ◽

M. L. O. PENIDO ◽

...

Keyword(s):

Schistosoma Mansoni ◽

Polyacrylamide Gel Electrophoresis ◽

Cross Reactivity ◽

Outer Side ◽

Western Blots ◽

Atp Diphosphohydrolase ◽

Antigenic Properties ◽

Egg Shell ◽

Net Charges ◽

Egg Antigen

The fact that the Schistosoma mansoni egg has two ATP diphosphohydrolase (EC 3.6.1.5) isoforms with different net charges and an identical molecular weight of 63000, identified by non-denaturing polyacrylamide gel electrophoresis and immunological cross-reactivity with potato apyrase antibodies, is shown. In soluble egg antigen (SEA), only the isoform with the lower net negative charge was detected and seemed to be the predominant species in this preparation. By confocal fluorescence microscopy, using anti-potato apyrase antibodies, the S. mansoni egg ATP diphosphohydrolase was detected on the external surface of miracidium and in von Lichtenberg's envelope. Intense fluorescence was also seen in the outer side of the egg-shell, entrapped by the surface microspines, suggesting that a soluble isoform is secreted. ATP diphosphohydrolase antigenicity was tested using the vegetable protein as antigen. The purified potato apyrase was recognized in Western blots by antibodies present in sera from experimentally S. mansoni-infected mice. In addition, high levels of IgG anti-ATP diphosphohydrolase antibodies were detected by ELISA in the same sera. This work represents the first demonstration of antigenic properties of S. mansoni ATP diphosphohydrolase and immunological cross-reactivity between potato apyrase and sera from infected individuals.

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Fasciola hepatica and Schistosoma mansoni: Immunofluorescent antigen localization and cross-reactivity

Experimental Parasitology ◽

10.1016/0014-4894(84)90055-9 ◽

1984 ◽

Vol 57 (1) ◽

pp. 1-14 ◽

Cited By ~ 11

Author(s):

Robert E.B. Hanna ◽

George V. Hillyer

Keyword(s):

Schistosoma Mansoni ◽

Fasciola Hepatica ◽

Cross Reactivity ◽

Antigen Localization

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Tissue expression of the Schistosoma mansoni 28 kDa glutathione S-transferase

Parasitology ◽

10.1017/s0031182000076447 ◽

1994 ◽

Vol 109 (5) ◽

pp. 565-572 ◽

Cited By ~ 20

Author(s):

E. Porchet ◽

A. McNair ◽

A. Caron ◽

J. P. Kusnierz ◽

K. Zemzoumi ◽

...

Keyword(s):

Schistosoma Mansoni ◽

Developmental Stages ◽

Tissue Expression ◽

Cross Reactivity ◽

Glutathione S Transferase ◽

Experimental Conditions ◽

Neural Mass ◽

Immunocytochemical Techniques ◽

Hepatic Granulomas ◽

Parenchymal Cells

The expression of the Schistosoma mansoni 28 kDa glutathione S-transferase (Sm28) was studied using molecular (PCR, in situ hybridization), and immunocytochemical techniques. The presence of Sm28 was demonstrated in all developmental stages of the parasite except the intra-uterine immature egg. In the parenchyma of male and female adult worms the distribution of Sm28 was limited to a subpopulation of parenchymal cells and to the dorsal tubercles of the male. The tegument, the muscles, the digestive tract, the neural mass, the vitelline glands, and mature gametes were not immunoreactive. Immature germinal cells in both sexes, and the ootype in the female genital system, were found to express Sm28. Deposits of immunoreactive material on host skin following cercarial penetration, exfoliation from the male tubercles, and especially emission of Sm28 from eggs in hepatic granulomas are suspected to be a source of antigen during the parasite infection. The reduction in worm fecundity previously observed in immunization experiments may result from an antibody response directed against Sm28 present in the ootype. There was no cross-reactivity observed, under the experimental conditions used, between the anti-Sm28 sera and either vertebrate or invertebrate host tissue.

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Antigenic cross-reactivity between Schistosoma mansoni and allergenic invertebrates putatively due to shared glycanic epitopes

Scientific Reports ◽

10.1038/s41598-020-59892-6 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Marwa H. El-Faham ◽

Fatou Gai ◽

Joseph E. Igetei ◽

Sarah Richter ◽

Franco H. Falcone ◽

...

Keyword(s):

Schistosoma Mansoni ◽

Cross Reactivity

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A loop-mediated isothermal amplification assay for Schistosoma mansoni detection in Biomphalaria spp. from schistosomiasis-endemic areas in Minas Gerais, Brazil

Parasites & Vectors ◽

10.1186/s13071-021-04888-y ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Silvia Gonçalves Mesquita ◽

Floria Gabriela dos Santos Neves ◽

Ronaldo Guilherme Carvalho Scholte ◽

Omar dos Santos Carvalho ◽

Cristina Toscano Fonseca ◽

...

Keyword(s):

Schistosoma Mansoni ◽

Lamp Assay ◽

Minas Gerais ◽

Cross Reactivity ◽

Molecular Techniques ◽

Isothermal Amplification ◽

Conventional Pcr ◽

Loop Mediated Isothermal Amplification ◽

Field Samples ◽

Collection Sites

Abstract Background Schistosomiasis a neglected tropical disease endemic in Brazil. It is caused by the trematode Schistosoma mansoni, which is transmitted by snails of the genus Biomphalaria. Among measures used to control and eliminate schistosomiasis, accurate mapping and monitoring of snail breeding sites are recommended. Despite the limitations of parasitological methods, they are still used to identify infected snails. Loop-mediated isothermal amplification (LAMP) is a sensitive, rapid, and cost-effective diagnostic method for the identification of infected snails. In the work reported here, we aimed to validate the use of LAMP for the detection of S. mansoni in snails of the genus Biomphalaria. Methods Snails were collected in five municipalities of the Mucuri Valley and Jequitinhonha Valley regions in the state of Minas Gerais, Brazil. Snails were pooled according to collection site and then squeezed for the detection of S. mansoni and other trematode larvae. Pooled snails were subjected to pepsin digestion and DNA extraction. Molecular assays were performed for species-specific identification and characterization of the samples. A previously described LAMP assay was adapted, evaluated, and validated using laboratory and field samples. Results Using the parasitological method described here, S. mansoni cercariae were detected in snails from two collection sites, and cercariae of the family Spirorchiidae were found in snails from one site. The snails were identified by polymerase chain reaction (PCR)–restriction fragment length polymorphism (RFLP). Biomphalaria glabrata, the main snail host of S. mansoni in Brazil, was detected in 72.2% of the collection sites. Biomphalaria kuhniana, which is resistant to S. mansoni infection, was found in the remaining sites. Multiplex, low stringency (LS), and conventional PCR allowed the detection of positive snails in four additional sites. Trematodes belonging to the families Strigeidae and Echinostomatidae were detected by multiplex PCR in two sites. The LAMP assay was effective in detecting the presence of S. mansoni infection in laboratory (7 days post-infection) and field samples with no cross-reactivity for other trematodes. When compared to LS and conventional PCR, LAMP showed 100% specificity, 85.7% sensitivity, and a κ index of 0.88. Conclusions Our findings suggest that LAMP is a good alternative method for the detection and monitoring of transmission foci of S. mansoni, as it was three times as effective as the parasitological examination used here for the detection of infection, and is more directly applicable in the field than other molecular techniques. Graphical abstract

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ABO Blood Groups Do Not Predict Schistosoma mansoni Infection Profiles in Highly Endemic Villages of Uganda

Microorganisms ◽

10.3390/microorganisms9122448 ◽

2021 ◽

Vol 9 (12) ◽

pp. 2448

Author(s):

Rachel Francoeur ◽

Alon Atuhaire ◽

Moses Arinaitwe ◽

Moses Adriko ◽

Diana Ajambo ◽

...

Keyword(s):

Schistosoma Mansoni ◽

Infection Intensity ◽

Cross Reactivity ◽

Blood Groups ◽

Blood Type ◽

Infection Dynamics ◽

Significant Public Health ◽

Mixed Regression ◽

Host Blood ◽

Linear Mixed Regression Model

Schistosoma mansoni is a parasite which causes significant public-health issues, with over 240 million people infected globally. In Uganda alone, approximately 11.6 million people are affected. Despite over a decade of mass drug administration in this country, hyper-endemic hotspots persist, and individuals who are repeatedly heavily and rapidly reinfected are observed. Human blood-type antigens are known to play a role in the risk of infection for a variety of diseases, due to cross-reactivity between host antibodies and pathogenic antigens. There have been conflicting results on the effect of blood type on schistosomiasis infection and pathology. Moreover, the effect of blood type as a potential intrinsic host factor on S. mansoni prevalence, intensity, clearance, and reinfection dynamics and on co-infection risk remains unknown. Therefore, the epidemiological link between host blood type and S. mansoni infection dynamics was assessed in three hyper-endemic communities in Uganda. Longitudinal data incorporating repeated pretreatment S. mansoni infection intensities and clearance rates were used to analyse associations between blood groups in school-aged children. Soil-transmitted helminth coinfection status and biometric parameters were incorporated in a generalised linear mixed regression model including age, gender, and body mass index (BMI), which have previously been established as significant factors influencing the prevalence and intensity of schistosomiasis. The analysis revealed no associations between blood type and S. mansoni prevalence, infection intensity, clearance, reinfection, or coinfection. Variations in infection profiles were significantly different between the villages, and egg burden significantly decreased with age. While blood type has proven to be a predictor of several diseases, the data collected in this study indicate that it does not play a significant role in S. mansoni infection burdens in these high-endemicity communities.

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Development and Evaluation of a Loop-Mediated Isothermal Amplification Assay for Diagnosis of Schistosoma mansoni Infection in Faecal Samples

Journal of Parasitology Research ◽

10.1155/2018/1267826 ◽

2018 ◽

Vol 2018 ◽

pp. 1-7 ◽

Cited By ~ 12

Author(s):

Ibrahim N. Mwangi ◽

Eric L. Agola ◽

Robert M. Mugambi ◽

Esther A. Shiraho ◽

Gerald M. Mkoji

Keyword(s):

Schistosoma Mansoni ◽

Color Change ◽

Lamp Assay ◽

Cross Reactivity ◽

Repeat Sequence ◽

Kappa Coefficient ◽

Isothermal Amplification ◽

Diagnostic Tools ◽

Loop Mediated Isothermal Amplification ◽

Faecal Samples

Human intestinal schistosomiasis is caused by the blood fluke, Schistosoma mansoni. With intensified efforts to control schistosomiasis by mass drug administration using praziquantel (PZQ), there is an urgent need to have accessible, quality-assured diagnostic tests for case detection and disease surveillance and for monitoring efficacy of treatment and other interventions. Current diagnostic tools are limited by suboptimal sensitivity, slow turn-around-time, affordability, and inability to distinguish current from past infections. We describe a simple and rapid diagnostic assay, based on the loop-mediated isothermal amplification (LAMP) technology for diagnosis of S. mansoni infection in human faecal samples. The LAMP primers used in this assay were previously described and they target a 121-bp DNA repeat sequence in S. mansoni. The LAMP assay was optimized at an isothermal temperature of 63°C for 1 hour. The amplified DNA was either visualized under ultraviolet light after electrophoresis or by directly observing the color change after staining the amplicons with CYBR Green dye. The LAMP assay was evaluated against the microscopy-based procedure and the results were analysed using Cohen’s kappa coefficient to determine the degree of agreement between the two techniques. The LAMP assay reliably detected S. mansoni ova DNA in faecal samples and parasite DNA in amounts as low as 32fg. When the assay was tested for specificity against other faecal-based soil-transmitted helminths (STH), no cross-reactivity was observed. The LAMP assay was superior to the Kato-Katz assay with a 97% specificity; a high positivity score reliably detecting S. mansoni and a Kappa Coefficient of 0.9 suggested an exceptional agreement between the two techniques. The LAMP assay developed has great potential for application in field settings to support S. mansoni control and elimination campaigns.

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