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BackgroundThis research was carried out to develop a reliable monoclonal antibody (MoAb)-based sandwich enzyme linked immunosorbent assay (ELISA) for the diagnosis of active Fasciola gigantica infection in both serum and stool for comparative purposes.MethodsFrom a panel of MoAbs raised against F. gigantica excretory/secretory antigens (ES Ags), a pair (12B/11D/3F and 10A/9D/10G) was chosen due to its high reactivity and strict specificity to F. gigantica antigen by indirect ELISA.ResultsThe two MoAbs were of the IgG1 and IgG2a subclasses, respectively. Using SDS-PAGE and EITB, the selected MoAbs recognized 83, 64, 45 and 26 kDa bands of ES Ags. The lower detection limit of ELISA assay was 3 ng/ml. In stool, the sensitivity, specificity and diagnostic efficacy of ELISA was 96%, 98.2 and 97.1%; while in serum they were 94%, 94.6% and 94.3%, respectively. Moreover, a positive correlation was found between ova count in stool of F. gigantica infected patients and the OD readings of ELISA in both stool and serum samples (r = 0.730, p < 0.01 and r = 0.608; p < 0.01, respectively).ConclusionsThese data showed that the use of MoAb-based sandwich ELISA for the detection of F. gigantica coproantigens in stool specimens was superior to serum samples; it provides a highly efficient, non-invasive technique for the diagnosis of active F. gigantica infection.

Few studies reported the antifibrotic effects of gallic acid (GA) despite its known hepatoprotective and antioxidant activities. Accordingly, this study investigated the antifibrotic effects of GA through clarifying its mechanisms on hepatic stellate cells' (HSCs) activation, proliferation and/or apoptosis. In vitro effects of GA on HSC-T6 activation/proliferation, morphology and safety on hepatocytes were assessed. In vivo, hepatic fibrosis was induced via chronic thioacetamide (TAA)-intoxication. TAA-intoxicated rats were treated with silyamrin or GA. At end of experiment, liver functions, hepatic MDA, GSH, PDGF-BB, TGF-β1, TIMP-1 and hydroxyproline were determined. Histological analysis and Sirius red staining of hepatic sections, expressions of alpha-smooth muscle actin (α-SMA), proliferating cellular nuclear antigen (PCNA) and caspase-3 were examined. In vitro, GA resulted in a concentration and time-dependent inhibition in HSCs activation, proliferation (IC50= 45 and 19 μg/mL at 24 and 48 h respectively); restored the quiescent morphology of some activated HSCs plus its safety on hepatocytes. In vivo, GA reduced ALT, AST, MDA, PDGF-BB levels, collagen deposition and fibrosis score (S1 vs S4); increased caspase-3 expression and restored GSH stores, TGF-β1 level, α-SMA and PCNA expressions. In conclusion, GA counteracted the progression of hepatic fibrosis through reduction of HSCs proliferation/activation mutually with their apoptosis induction.

A monoclonal antibody (mAb), 2F/11F, raised against Schistosoma haematobium soluble egg antigen (SEA) was found to be nonreactive with S. mansoni SEA or other parasite antigens (Fasciola hepatica, Echinococcus granulosus). This IgG1 mAb recognized a repetitive epitope on S. haematobium SEA in the molecular-weight regions of 70, 42, and 35 kDa. It was employed as both an antigen-capture and a biotinylated detection antibody in a sandwich enzyme-linked immunosorbent assay (ELISA) for the detection of circulating schistosome antigen (CSA) and had a detection limit of <1 ng S. haematobium SEA/ml. CSA levels were measured in serum and urine samples from 116 S. haematobium-infected rural students before therapy and at 4, 8, and 12 weeks after praziquantel treatment. Serum and urine samples from 50 S. mansoni -infected patients, 15 patients harboring other parasites, and 30 noninfected individuals were also assessed. CSA was detected in 90.5% of serum samples and 94% of urine samples from S. haematobium-infected patients. CSA was undetectable in serum from the 15 patients harboring other parasites and in 94% of serum samples and 84% of urine samples from S. mansoni-infected patients. In the S. haematobium-infected group a positive correlation was detected between CSA levels in serum and urine samples and the egg load per 10 ml urine. A significant reduction in CSA levels was detected in serum and urine samples after praziquantel therapy. CSA was undetectable in 87% of serum samples and 81.5% of urine samples from schistosomiasis haematobium patients at 12 weeks post-treatment. These data demonstrate that the use of mAb 2F/11F for detection of CSA provides a sensitive method for the immunodiagnosis and monitoring of cure of schistosomiasis haematobium.

Mesenchymal stem cells (MSCs) therapy show different levels of effectiveness in the context of different types of liver damage, suggesting that the microenvironment of the injured liver is a key determinant for effective stem cell therapy. The objective was to assess the modulatory effect of hepatic stem cell niche components on the transplanted MSCs during liver injury induced by carbon tetrachloride (CCl4). Superparamagnetic iron oxide (SPIO)-labeled human MSCs were injected intravenously into mice treated with CCl4 and subjected to hepatic macrophage-depletion. Liver tissues were collected at different intervals post transplantation for subsequent histopathological, morphometric, immunohistochemical, gene expression and ultrastructural studies. The homing of the transplanted MSCs was evidenced by tracing them within the niche by iron staining and immunohistochemical studies. MSCs differentiated into hepatocyte-like cells and intimal smooth muscle cells as evidenced by their expression of human albumin and α-smooth muscle actin with a concomitant increase in the level of mouse hepatocyte growth factor. A post transplantation reduction in the liver fibro-inflammatory reaction was found and was promoted by liver macrophages depletion. Thus, it could be concluded from the present study that prior manipulation of the microenvironment is required to improve the outcome of the transplanted cells.