Development of a rapid dipstick with latex immunochromatographic assay (DLIA) for diagnosis of schistosomiasis japonica (original) (raw)

Evaluation on the applied value of the dot immunogold filtration assay (DIGFA) for rapid detection of anti-Schistosoma japonicum antibody

Acta Tropica, 2005

The dot immunogold filtration assay (DIGFA) is a rapid technique for the detection of anti-Schistosoma japonicum antibody. Its sensitivity with regard to sera obtained from patients with acute or chronic schistosomiasis was shown to be 100 and 96.9%, respectively. The specificity when using sera of people living in an area non-endemic for schistosomiasis japonica was 100%. Cross-reaction rates for paragonimiasis and clonorchiasis patients were 14.3% and 0%, respectively. Parallel serum tests of 1091 residents from an area endemic for S. japonicum by means of DIGFA, enzyme-linked immunosorbent assay and indirect haemagglutination test resulted in positive rates of 9.3%, 11.5% and 11.0%, respectively. Thus, there was a high level of agreement between the sets of results (P > 0.05). In conclusion, DIGFA holds considerable promise for rapid and accurate diagnosis of S. japonicum, as it does not require any specific instruments and can be applied with ease. DIGFA has therefore several advantages over conventional diagnostic approaches and is useful not only for screening and sero-epidemiological surveys in the field, but also in clinical settings.

Performance of a dipstick dye immunoassay for rapid screening of Schistosoma japonicum infection in areas of low endemicity

Parasites & Vectors, 2011

Background: The dipstick dye immunoassay (DDIA), recently commercially available in the People's Republic of China (P.R. China), is a rapid and simple test to detect human antibodies against Schistosoma Japonicum. Its performance and utility for screening schistosome infection in low endemic areas is little known. We therefore carried out a cross-sectional survey in seven villages with low endemicity of schistosomiasis in P.R. China and assessed the performance and utility of DDIA for diagnosis of schistosomiasis. Stool samples were collected and examined by the Kato-Katz method and the miracidium hatching technique. Serum samples, separated from whole blood of participants, were tested by DDIA.

Profile of Antigen Excretory-Secretory Schistosoma Japonicum in the Development of Elisa Method to Detect Schistosomiasis in Indonesia

2021

The development of ELISA method to detect patients with schistosomiasis in Indonesia is a detection of the antigens that are derived from the peripheral vessels in the blood serum. This research is conducted in the Napu Plateau of Poso Regency, Central Sulawesi, Indonesia. The goal is to develop ELISA method with polyclonal antibodies to detect antigenic-excretory antigen of S. japonicum in patients with schistosomiasis. Activities in the study include activities in the field namely the isolation of worm S. japonicum and activities in laboratories such as production, characterization and purification by Bradford methods as well as electrophoresis test to see the protein Antigen profile. The results of the study of the 30 worm Schistosoma collected from 5 rats suffered schistosomiasis, obtained as much as 42.5 ml with a protein concentration of 1.351 mg/ml, and had two patterns of polypeptide tape with a molecular weight range of 20 and 39 Dalton kilo (kDa). The conclusion of the res...

Development of a rapid, simple dipstick dye immunoassay for schistosomiasis diagnosis

Journal of Immunological Methods, 2002

In order to develop a rapid, simple immunodiagnostic assay for schistosomiasis, soluble egg antigen (SEA) of Schistosoma japonicum was conjugated with a blue colloidal dye (D-1) produced in China and used to detect antibodies in the sera of schistosomiasis patients. The antigen -antibody complex was captured by anti-human IgG absorbed onto a nitrocellulose membrane dipstick by means of immunochromatography. The results showed that the sensitivity of the dipstick dye immunoassay (DDIA) was 96.7% in 30 cases of acute schistosomiasis (29/30) and 94.1% (79/84) in 84 cases of chronic schistosomiasis. The specificity of the assay was 96.7% in 60 healthy subjects. Cross-reactions were observed in 10.0% of 20 cases of clonorchiasis and in 70.0% of 20 cases of paragonimiasis. The results were similar to those detected by routine ELISA. In a field evaluation of the DDIA kit, the positive rate of the DDIA was 96.7% in 121 cases of schistosomiasis, compared with 90.1% with the circumoval precipitin test (COPT) . The antigen conjugated with dye was stable at room temperature for at least 6 months. The results indicated that the dipstick dye immunoassay provided high sensitivity and good specificity for the detection of schistosomiasis and the assay was rapid, simple and cheap, and did not need any equipment. It was more useful for screening target populations for selective chemotherapy than other immunoassays. D

Evaluation of immunoassays for the diagnosis of Schistosoma japonicum infection using archived sera

PLoS neglected tropical diseases, 2011

With a national program initiated recently to reduce transmission of Schistosoma japonicum in the People's Republic of China (P.R. China), there is an urgent need for accessible, quality-assured diagnostics for case detection, surveillance, and program monitoring of chemotherapy efficacy and other control interventions in areas of low endemicity. We compared the performance of nine immunodiagnostic tests developed in P.R. China for detection of antibodies against S. japonicum and established their priority for further assessment in field settings. Using the Kato-Katz technique as the reference standard, 240 well-characterized archived serum specimens (100 positive and 140 negative) were evaluated in nine immunological tests developed in P.R. China. The enzyme-linked immunoelectrotransfer blot assay (EITB), which uses an adult worm extract of S. japonicum, supplied by the Center of Disease Control and Prevention, USA, was also evaluated. The sensitivity and specificity of each te...

A Novel Immunodiagnostic Assay to Detect Serum Antibody Response against Selected Soluble Egg Antigen Fractions from Schistosoma japonicum

PLoS ONE, 2012

Background: Schistosomiasis japonica remains a real threat to public health in China. The currently used immunodiagnostic assays are sensitive and have a certain degree of specificity, however, they all use complex crude antigens, are based on detection of schistosome-specific antibodies, and have been shown to cross-react with other parasitic diseases. Therefore, these assays cannot be used to evaluate chemotherapy efficacy. The development of highly sensitive and highly specific immunodiagnostic techniques that can monitor the decline of antibodies specific for S. japonica will be extremely valuable as part of the ongoing strategy to control schistosomiasis in endemic areas. Here we report on the identification of unique fraction antigens of soluble egg antigen (SEA) to which the antibodies disappear 7 weeks after effective treatment. Furthermore, we use these SEA fractions to develop a modified assay with both high sensitivity and specificity. Methodology/Principal Findings: SEA of S. japonicum was fractionated by electrophoresis using 7.5% SDS-PAGE under non-reducing conditions. The SEA fraction antigens to which antibodies were decreased soon after treatment were collected and used as the detection antigens to establish the FA-ELISA. Sera from patients with acute and chronic schistosomiasis infection, healthy people, and those with other parasitic diseases, were used to evaluate their sensitivity and specificity. Furthermore, sera from patients with chronic schistosomiasis infection were evaluated before and after treatment at different time points to evaluate their chemotherapeutic efficacy. Conclusion/Significance: We demonstrated that this novel FA-ELISA provided high sensitivity and specificity, with very low cross-reactivity, and can serve as an effective tool to determine the efficacy of chemotherapy against S. japonicum.

Use of Schistosoma mansoni soluble egg antigen (SEA) for antibody detection and diagnosis of schistosomiasis: The need for improved accuracy evaluations of diagnostic tools

Acta Tropica, 2021

Many antigens for use in antibody-detection systems for schistosomiasis have been investigated over the past 40 years. In particular, soluble egg antigens (SEA) are still widely used in enzyme-linked immunosorbent assays (ELISAs) for detection of immunoglobulin classes and subclasses. Here, we conducted a literature review to examine accuracy evaluations of SEA-Immunoglobulin G (IgG)-ELISAs performed to detect Schistosoma mansoni infections and published between 1979 and 2019. S. mansoni is the main causative agent for intestinal schistosomiasis in many countries in Africa and Central and South America. After retrieving 214 relevant abstracts from the PubMed database, we selected 15 publications to undergo a full review. Sensitivity and specificity values varied from 71 to 99%, and from 6 to 100%, respectively. In addition, 11/15 studies did not state confidence intervals. Therefore, the findings from this review indicate that after four decades, we still do not have consistent evaluation estimates of SEA-IgG-ELISAs. Antigen mass per well and dilution of test sera in these articles varied from 0.018 µg to 1.5 µg, and from 1:50 to 1:500, respectively. Most of the reported accuracy evaluations used control sera which were selected based on parasitological examinations for egg detection, although ill-defined criteria were also noted. The number and composition of control serum panels was considered not adequate in approximately half of the studies. It is also noteworthy that among more than 30 diagnostic antigen preparations under development since the 1970s, most were not validated in the field and they failed to reach populations in need. Thus, attention to guidelines for standardization, estimations of accuracy, and reporting of results is needed to facilitate coordinated efforts aimed at schistosomiasis control and elimination.

Comparison of Kato Katz, antibody-based ELISA and droplet digital PCR diagnosis of schistosomiasis japonica: Lessons learnt from a setting of low infection intensity

PLOS Neglected Tropical Diseases, 2019

Background Zoonotic schistosomiasis in Asia, caused by Schistosoma japonicum, remains a major public health concern in China and the Philippines. The developing epidemiological and socioeconomic picture of the disease in endemic areas necessitates the development of affordable and highly accurate field diagnostics as an important component in evaluating ongoing integrated control and elimination efforts. Methods Three diagnostic methods, namely Kato-Katz (KK) stool microscopy, ELISA and droplet digital (dd) PCR assays, were compared by detecting infection in a total of 412 participants from an area moderately endemic for schistosomiasis in the Philippines. Results This comprehensive comparison further defined the diagnostic performance and features for each assay. Compared with the ddPCR assay analysing DNA from faeces (F_ddPCR), which exhibited the highest sensitivity, the SjSAP4 + Sj23-LHD-ELISA had the best accuracy (67.2%) among all five ELISA assays assessed. Schistosomiasis prevalence determined by the SjSAP4 + Sj23-LHD-ELISA and ddPCRs was similar and was at least 2.5 times higher than obtained with the KK method. However, the agreement between these assays was low. In terms of cost and logistical convenience, the SjSAP4 + Sj23-LHD-ELISA represents a cost-effective assay with considerable diagnostic merits. In contrast, although the ddPCR assays exhibited a high level of diagnostic performance, the high cost and the need for specialized equipment presents a major obstacle in their application in screening campaigns.

A monoclonal antibody-based dot immunogold filtration assay: a rapid field applicable technique for immunodiagnosis of active schistosomiasis

2009

21 Abstract: A simple and rapid dot-immunogold filtration assay (DIGFA) technique was used in the present study for rapid detection of antigenaemia in the sera of schistosomiasis patients, using a pair of monoclonal antibodies, the first as antigen capture and the second labeled with red color colloidal gold as antigen detector. Sandwich - ELISA technique, dot-ELISA and dipstick ELISA were used in comparison with the DIGFA technique to evaluate its sensitivity and specificity. The results showed that the percentage positivity of antigenaemia in scistosomiasis patients' sera, using sandwich-ELISA technique was 100%, while in dot-ELISA and dipstick-ELISA the positivity rate was 89.7% and 91.2% respectively. The DIGFA technique showed 97.1% positivity, while the sensitivity and specificity of DIGFA were 95.8% and 95% respectively. In sandwich-ELISA, dot-ELISA and dipstick-ELISA the sensitivity was 100%, 90.7% and 91.9% respectively, and the specificity was 96.6%, 91.9% and 91.9% re...