Development of new lateral-flow immunochromatographic strip using colloidal gold and mesoporous silica nanoparticles for rapid diagnosis of active schistosomiasis

Objective: To develop a new sandwich based lateral flow immunochromatographic strip for rapid detection of circulating Schistosoma mansoni antigen in serum and urine samples of patients with active schistosomiasis. Methods: This lateral flow immunochromatographic strip was prepared by using anti-Schistosoma mansoni soluble egg antigen monoclonal antibody conjugated gold nanoparticles (MAb-AuNPs) as antigen-detecting antibody, while crystalline material (MCM)-41-MAb bioconjugate was immobilized at the test line as antigen-capturing antibody. Both antigen capturing and detecting antibodies formed sandwich complexes with circulating Schistosoma mansoni antigen in the positive samples. Sandwich complexes immobilized at the test line gave distinct red color. The assay reliability was examined by using urine and serum samples of 60 Schistosoma mansoni infected patients, 20 patients infected with parasites other than Schistosoma, and 20 healthy individuals as negative controls. Results were compared with those obtained via sandwich enzyme linked immunosorbent assay (ELISA). Results: The detection limit of circulating Schistosoma mansoni antigen by lateral flow immunochromatographic strip was lower (3 ng/mL) than the detection limit by ELISA (30 ng/mL). The sensitivity and specificity of lateral flow immunochromatographic strip in urine samples were 98.3% and 97.5%, respectively compared to 93.5% and 90.0% by ELISA. In serum samples, they were 100.0% and 97.5%, respectively compared to 97.0% and 95.0% by ELISA. The strip test took approximately 10 min to complete. Conclusions: This new lateral flow immunochromatographic strip offers a sensitive, rapid, and field applicable technique for diagnosis of active schistosomiasis.

Angiogenic potential of human umbilical cord blood ex vivo expanded CD 133* stem cells in chronic hepatic fibrosis of murine schistosomiasis

As a source of hematopoietic stem cells [HSCs], umbilical cord blood [UCB] has the advantages of speed of availability, tolerance of more than one HLA mismatch, and a low incidence of severe graft-versus-host disease [GVHD]. Hence, it represents a promising, alternative non-costly and non-invasive source for prospective stem cell based therapy. In this study we investigated the angiogenic potential of ex vivo expanded human umbilical cord blood CD 133* stem cells transplanted into mice with chronic hepatic fibrosis induced by Schistosomiasis infection. Histopathological, ultrastructural and immunohistochemical analysis of mice liver sections were done to detect specific human angiogenic markers. Umbilical cord blood was obtained from healthy pregnant females after delivery and mononuclear cells were collected by density gradient using Ficoll Hypaque. Enrichment for the CD 133* stem cells was done by positive selection using the Magnetic Activated Cell Sorting system and magnetic microbeads. Cells were cultured in prirnaly ex vivo expansion medium for three weeks. Flowcytomeric analysis of the cultured cells was done in each step to identify the CD 133* cells. Schistosomiasis was induced in Swiss Albino mice by intradermal injection of schistosoma cercariae. Twenty two weeks post schistosoma infection a total of 0.3 x 106 human CD 133* stem cells were injected intrahepatically in mice. Accordingly, mice were divided into three groups: Group 1 [infected, transplanted]; Group 2 [infected controls] and Group 3 [healthy, transplanted]. All mice were sacrificed 3 wks after cell transplantation was done in groups I and 3. Histopathology and Electron microscopy showed an obvious increase in the capillary network and the small blood vessels and a decrease in the fibrosis known for this stage of the disease. By immunohistochemical analysis the cellular constituents of these newly formed blood vessels showed positive expression of the human-specific angiogenic markers CD31, CD34 and von Willebrand Factor [vWF]. Few hepatocyte like polygonal cells showed positive expression of human Vascular Endothelial Growth Factor [VEGF] and inducible Nitric Oxide Synthase [iNOS]. Ex vivo expanded CD 133* human stem cells incorporate into the liver of schistosoma infected mice enhancing local angiogenesis and hepatic neovascularization. These preliminary results obtained suggest a dual benefit of CD 133* cells in cell therapy in hepatic diseases based on its capability of hematopoietic and endothelial differentiation. We suggest that the CD 133* cells contribute to repair in a paracrine manner by creating a permissive environment that enables rapid proliferation and survival of damaged cells rather than through direct differentiation to hepatocytes

Immunodiagnosis of human Wuchereria bancrofti infection using a pair of monoclonal antibodies against worm antigen

This study was designed to prepare monoclonal antibodies [MAbs] against filarial worm antigen [FWA] with immunodiagnostic potential for human filariasis. These MAbs were initially screened and then tested for their specificities against different parasite antigens [S.mansoni SEA, Echinococus granulosus and Fasciola hepatica] by ELISA. From a panel of anti-filarial antigen MAbs; a pair of MAbs [9F/10B and 5F1 611], highly reactive with filarial antigen and showing no cross reactivity against other parasites antigens were selected and characterized. The pair was found to be of IgG1 subclass. Identification of target antigens recognized by MAbs was performed using immunoelectrophoresis, SDS-polyacrylamid gel electrophoresis and enzyme-linked immunoelectrotransfer blot techniques. Both MAbs recognized one band with 88 kDa molecular weight by western blots. Chemical nature of MAbs target antigens was identified by periodate treatment method and proved to be glycoprotein in nature. The pair of MAbs was employed in sandwich ELISA for the defection of circulating filarial antigen [CFA]; one MAb [9F/10B] was used as antigen capturing antibody and the other [5F/6H] as peroxidase-conjugated antigen detecting antibody. The assay reached a lower detection limit of 125 ng/ml of filarial antigen. CFA levels were measured in serum samples from 71 filariasis patients [47 with microfilaraemia and 24 with elephantiasis], 45 patients with other parasites including schistosomiasis, fascioliasis and echinococcosis and 39 healthy individuals as negative control. CFA levels were detected in sera of 68 out of 71 filariasis patients showing an overall sensitivity of 95.8% [91.7% sensitivity for microfilaraemia group and 100% sensitivity for elephantiasis group]. All negative control sera were negative for CFA, while 3 patients out of the other parasite group were positive for CFA giving an overall specificity of 96.4%. These findings suggest that [9F/IOB] MAb and [5F/6H] MAb could be used as a reliable diagnostic indicator for the activity of human filariasis and as a cure monitor particularly in control programs for endemic areas

Intraperitoneal injection of echinostome antigens confers resistance to schistosomal infection in murine model

The effect of immunization protocol against S. mansoni infection with purified metacercarial antigen from E. liel alone or combined with BCG on resistance to S. mansoni infection and associated immunoparasitological changes in murine experimental model was studied. The results revealed highly significant reduction in worm burden and hepatic and intestinal tissue egg loads were observed on comparing the two immunized groups [purified metacercarial antigen alone or purified metacercarial antigen plus BCG] with the infected control group [p> 0.001]. Moreover the greatest reduction in the worm burden was observed in group injected with purified metacercarial antigen pluse BCG. A significant reduction [p> 0.001] was observed in granuloma diameter in the two immunized groups relative to infected control. However, the greatest reduction in granuloma diameter was noticed in group II [purified metacercarial antigen pluse BCG]. No significant difference was observed in granuloma diameter berween the two immunized groups. Anti-SEA serum specific immunoglobulins in group I and group II showed a significant increase in both IgG and IgM [p> 0.05] compared to the infected control group. A higher significant increase was found in the specific immunoglobulin isotype IgGI [p> 0.001] in both group I and II compared to infected control group. In conclusion, our findings showed that multiple intraperitoneal adminestration of purified metacercarial antigen induce highly significant reduction in worm burden, hepatic and intestinal tissue egg loads and granuloma size 8 weeks post infection

Influence of long term immersion of heat-cured silicone soft liner in denture cleanser

This study was conducted to identify the effect of long-term immersion of heat-cured silicone soft liner Molloplast-B in a new alkaline peroxide formulation on its elastic behavior as well as its surface hardness. From the results obtained, it was concluded that daily immersion of Molloplast-B in New Steradent Aktiv 3 denture cleanser and surface characteristics, while only 10-minute or 8-hour immersion per week did not alter these properties. The bacteriological study proved that 8-hour immersion, once every week, in New Steradent Aktiv 3 was sufficient enough as a disinfectant to inhibit fungal growth on Molloplast-B. On the other hand, 10-minute immersion per week was not enough for that inhibition. 8-hour immersion in New Steradent Aktiv 3 can be confidently recommended as an effective and safe denture cleaner for patients wearing dentures lined with Molloplast-B

Prosthodontic rehabilitation of oligodontia

Seven children [their age ranged from 8-12 years] complaining from partialanodontia and/or delayed eruption of teeth were included in this work. Acrylic resin partial dentures were constructed for each child and anyorofacial changes were evaluated. Most dentures required to be replaced orchanged. Cephalometric X-ray were performed for each child [before and afterwearing dentures] to evaluate any change in facial height. The evaluationrevealed increase in lower facial height of five children, while the other 2children showed no dimensional changes. A follow up period for 3 years,showed that acrylic resin partial dentures were extremely valuable aids in thetreatment of young children with partial anodontia