monoclonal antibody-based latex agglutination test for detection of circulating schistosomal antigens in human schistosomiasis maizsoni

Schistosomiasis is a major public health problem with a worldwide distribution, Diagnosis of this disease by simple and rapid immunoassays is a priority. The objective of the present study was to standardize and evaluate the latex agglutination test [LAT] as a simple test for the detection of circulating schistosomal antigen [CSA] in serum and urine samples of S. mansoni patients and compare it with ELISA. According to stool examination this study included, 52 S. mansoni infected patients, 20 other parasites infected patients and 20 negative control samples. A polystyrene latex [0.81 micro m] suspension was used as a carrier particle for anti-S. mansoni adult worm tegumental antigen monoclonal antibody [l2D/10F] in the test. The Latex particles sensitized with MAb were used for the detection of CSA in urine and serum samples. The sensitivity of LAT assay was 88.5% in urine and 86.6% in sera versus 90, 4% and 92.3% for ELISA. The specificity of LAT assay was 90% and 95% for urine and sera versus 85% and 95% for ELISA. The diagnostic efficacy of EAT was 89.1% and 90.2b for urine and serum samples, respectively versus 88% and 93.5% for ELISA. Moreover, a positive correlation was found between ova count in stool of S. mansoni infected patients and both the intensity of LAT and OD readings of ELISA in urine [r= 0.922; p< 0.001 and r= 0.865; p< 0.001, respectively] and in serum [r=0.847; p< 0.001 and r= 0.781; p< 0.001, respectively]. In conclusion, LAT is a suitable applicable diagnostic method in field survey especially when followed by ELISA as a confirmatory test in query false negative results. In the same time, more trials are required to increase the sensitivity and specificity of LAT to allow its use on a large scale in field surveys and as diagnostic kits for multiple parasitic infections

Evaluation of purified tegumental antigen of Fasciola adult worm In diagnosis of human fasciollash

This study was designed to develop a sandwich ELISA for detection of Fasciola antigens in stool and sera of fascioliasis patients as a better diagnostic alternative to routine parasitological methods. Anti-Fasciola antibodies were produced by immunization of rabbit with Fasciola purified tegumental antigen [PTA] obtained from worms collected from livers of cattle infected with Fasciola. Raised antibodies were then employed in sandwich ELISA for detection of Fasciola antigen in collected sera and stool samples. In this study sera and stool samples from 40 Fasciola infected patients, 30 patients infected with other parasites [Schistosoma, Hydatid and Ancklystoma] and 20 uninfected individuals were tested by sandwich ELISA for detection of Fasciola antigen. The sensitivity of coproantigen assay reached 90% for detection of Fasciola antigens in stool and 87.5% for detection of Fasciola antigen in sera of fascioliasis patients. The specificity of the assay was 94% for stool samples and 92% for sera of negative controls and patients harboring other parasites collectively. The diagnostic efficacy of the assay was 92.2% and 90% for stool and serum samples, respectively. Moreover, a positive correlation was found between ova count in stool of Fasciola infected patients and antigen levels in both sera and stool samples [r= 0.456, p< 0.01; r=0.532, p< 0.01]. In conclusion, our data demonstrated that the employment of rabbit anti-Fasciola IgG antibodies in sandwich ELISA for the detection of Fasciola coproantigen in stool provided a sensitive and specific tool for immunodiagnosis of Fasciola infection

DNA vaccination using schistosoma mansoni fimbrin gene on naive and infected praziquantel-treated mice

DNA immunization represents a promising vaccine strategy that has been reasonably successful, and will likely play a greater role in vaccine research development against Schistosoma mansoni [S. mansoni]. S. mansoni fimbrin [Smfim] gene which encodes a putative actin bundling tegumental and immunogenic protein has been cloned into the eukaiyotic expression vector pcDNAI/Amp and used for intra-muscular DNA vaccination of Swiss albino mice. Two experimental models were used to study its role on protection against S. mansoni infection in naive mice [model 1] and to explore its effect on infected praziquantel [PZQ]-treated mice [model 2] using different immunological, parasitological and histopathological parameters. In the first model, Smfim-vaccinated mice showed high anti-Smfim IgG titer and acquired a significant protection [43.2%; p< 0.01] with reduction of ova count in both hepatic and intestinal tissues [59.2% and 5 1.1% respectively, p< 0.01], significant reduction of granuloma count [24.1%; p< 0.01] and granuloma diameter [18.3%

Synergistic effect calcium channel blockers and praziquantel treatment in murine schistosomiasis

This work was conducted to study the potential drug interaction between calcium channel blockers [CCBs], commonly used as antihypertensives, and the antihelminthic agent praziquantel [PZQ] in Schistosoma mansoni infected mice. Two CCBs namely nifedipine and diltiazem were used either alone or in combination with PZQ, in full or reduced doses [500 mg/kg/day for 2 successive days or 250 mg/kg/day]. The experimental design included eight groups; infected-nifedipine treated [300 mg/kg for 3 weeks [wks]]; infected-nifedipine-PZQ treated; infected-diltiazem treated [300 mg/kg for 3 wks]; infected-diltiazem-PZQ treated; infected control and infected-PZQ treated. Eight wks postinfection [Pt] animals of all groups were sacrificed for subsequent parasitological, immunological and histopathological assessment. Data collected in this work revealed that treatment with nifedipine or diltiazem significantly reduced the egg production by adult schistosome worm as manifested by reduction in tissue egg load and decreased percent of immature ova in oogram pattern. This reduction was more in favor with nifedipine. The groups given the combined regimens of CCBs [nifedipine or diltiazem] and PZQ either in reduced [250 mg/kg/day] or full [500 mg/kg/ day] doses, showed more significant reduction in egg production in addition to high significant reduction in worm burden, as compared to infected control group. The number of granukima also decreased significantly in all treated groups; this could be due o decrease in egg production. The antischistosomal IgG level was increased significantly in PZQ-treated group and groups receiving combined regimens of CCBs and PZQ with different doses; while no significant change in the IgM levels was recorded among different studied groups. In conclusion administration of CCBs in the early phase of infection would inhibit egg production by parasitic worms, thus probably acting in synergy with PZQ and not interfering with its action. Further studies are needed to evaluate the possible use of lower doses of PZQ in combination with CCBs. The reported data of this work may be of value in endemic areas where schistosome infected patients could be suffering from other chronic diseases necessitating treatment with CCBs, as hypertension