Effect of nanoparticles on the therapeutic efficacy of praziquantel against Schistosoma mansoni infection in murine models.

Praziquantel (PZQ) is the main treatment of Schistosomiasis mansoni. However, resistance to it was described. So, there is a necessity to develop novel drugs or to enhance the present drugs. This work aimed to assess the efficacy of PZQ alone and when loaded on liposomes in treatment of S. mansoni infection by parasitological and histopathological studies in experimental murine models. 112 male laboratories bred Swiss Albino mice were used in this work. They were divided into four groups: Group 1: control group; Group 2: infected then treated by PZQ (500 mg/kg) at 7, 30 and 45 days post infection; Group 3: infected then treated by liposome encapsulated PZQ (lip.PZQ) (500 mg/kg) at 7, 30 and 45 days post infection; Group 4: infected then treated by free liposomes at 7, 30 and 45 days post infection. The results showed that G3 caused the highest significant reduction of the total worm count, eggs/gram liver tissue and intestine (97.2%, 99.3%, 99.5%) respectively. Followed by G2 (85.1%, 97.6%, 89.8%) respectively. Regarding the histopathological studies, G3 showed the highest significant reduction in number and diameter of hepatic granuloma (97.6% and 98.1%), followed by G2 (77.2% and 75%) when compared to other groups. In conclusion, lip.PZQ is more effective than free PZQ from all aspects especially when administered 45 days PI.

Assessment of spiramycin-loaded chitosan nanoparticles treatment on acute and chronic toxoplasmosis in mice.

Toxoplasmosis is a zoonotic parasitic disease with worldwide distribution. Chitosan is a natural polymer which is commonly used in the production of nanomedicines. It is known to enable higher drug permeation, being biocompatible and has very low toxicity, besides its antimicrobial effects. Our study aimed to assess the effect of spiramycin-loaded chitosan nanoparticles (SLCNs) in treatment of acute and chronic toxoplasmosis in mice. 200 male Swiss albino mice were included in our study, divided to two main groups; Toxoplasma gondii RH strain infected group and ME49 strain infected group, each main group was subdivided into four subgroups; subgroup I: infected control, subgroup II: infected and received chitosan nanoparticles (CS NPs); 20 µg of CS NPs in 100 µl of PBS/mouse/dose, subgroup III: infected and treated with spiramycin (Rovamycin); 100 mg/kg/day, subgroup IV: infected and treated with 100 mg/kg/day spiramycin-loaded chitosan nanoparticles. Effect of treatment was assessed parasitologically and histopathologically. It was noticed that SLCNs significantly decreased the mortality rate of infected mice with both strains compared to high mortality rate of mice in the infected control subgroups. Moreover, there was a significant decrease in the number of organisms of SLCNs treated subgroup as compared to the other subgroups. Histopathological studies showed a marked improvement of the pathological pictures of brain, liver, spleen and eye in the subgroup received SLCNs as opposed to other groups. In conclusion, the present study revealed that loading of spiramycin on chitosan nanoparticles increased its antiparasitic effect on acute and chronic T. gondii infection.

Murine hepatocytes DNA changes as an assessment of the immunogenicity of potential anti-schistosomal vaccines experimentally.

Hepatic affection by granulomatous inflammation in schistosomiasis suggested that a potential anti-pathology vaccine could be generated based on limiting the presence of hazardous hepatocytes induced apoptosis and caused reduction of granulomas number and size . So, this work is concerned with experimental assessment of the efficacy of different Schistosoma mansoni antigens (SEA, SWAP and combined SEA and SWAP) on murine liver after challenge by Schistosoma infection, histopathological, histochemical and molecular investigations were performed on sixty male laboratory bred Swiss Albino mice. A schedule of vaccination and challenge infection was followed and performed on 6 mice groups (each of ten); control normal (G1), control infected (G2), adjuvant received then infected (G3), SEA + adj. received then infected (G4), SWAP + adj. received then infected (G5) and SEA + SWAP + adj. received then infected (G6).Animals were euthanized 10 weeks post infection.Vaccination efficacy was assessed by histopathological, histochemical and molecular studies on murine hepatic tissues.Results showed that:The combined (SEA + SWAP) antigens were better in reducing the number and diameter of the hepatic granulomas, with more protection of the hepatocytes DNA, in addition to more decrease of hepatocytes induced apoptosis and fragmentation as demonstrated by molecular assay.

The relation between the prevalence of soil transmitted parasites in the soil and among school children in Zagazig district, Sharkyia Governorate, Egypt.

Soil transmitted helminths are highly prevalent throughout the developing countries of the world and Egypt is categorized as one of the developing countries. This study aimed to detect the relation between the presence and prevalence of STH in the soil and their reflection on the prevalence among school-children living in rural and urban areas in Zagazig district, Egypt. The present study was carried out on (859) school-children aged 6-13 years in Zagazig district all over the year 2013. They were subjected to stool examination. Out of them 100 suspected children were serotested for anti-TES IgG antibodies Toxocara spp. Soil samples also were collected from their places and regions. The results showed overall prevalence of parasitic infections was 21.07 % for helminthic infection and 39.46 % for protozoa. The prevalence of parasitic infections was more among children in rural areas (28, 49.2, 11.1 %) than those who live in urban areas (6.4, 18, 2.2 %) for helminths, protozoa and Toxocara as the most prevalent helminth respectively. Highly significant association was found between soil-transmitted helminthic infections detected by stool examination of the studied children group and the prevalence of geohelminthes in the examined soil samples, taken from residency areas of those children. This association was missed regarding protozoal infections. According to the results, low level of education and consequently poor socio-economic and hygienic conditions of families appear to be powerful determinants of infection. Thus, improving environmental sanitation is imperative for the control of soil-transmitted helminths.

Geohelminths distribution as affected by soil properties, physicochemical factors and climate in Sharkyia governorate Egypt.

Soil-transmitted helminths are mainly a group of parasitic nematodes causing human infection through contact with parasite eggs or larvae; they survive in the warm and moist soil of the tropical and subtropical countries. This study was carried out in Sharkyia governorate from October, 2011 to October, 2013, to correlate between the prevalence and distribution of these parasites in the soil and the physicochemical factors affecting the examined samples of the soil. One hundred and twenty samples of different types of soil (clay, silt, sand) from different localities were collected and examined. Diagnosis of geohelminths was confirmed by the recovery of their eggs and larvae with other protozoa by different parasitological methods. The modified baermann method was found to be more efficient in detection of geohelminths larvae than charcoal culture method. Among the examined sites geohelminths were much more numerous in the soil of rural areas especially in the spring and summer seasons, while the contamination of canal banks by geohelminths was the worst (80 %). An insignificant correlation was reported between the soil texture and the number of positive samples in the examined areas while the relationship was directly proportional among (moisture, PH, organic). It appeared that the most common geohelminthic stage was Toxocara spp. eggs besides other types of protozoa especially Balantidium coli cysts. This suggests that factors other than soil texture are important in the prevalence of geohelminths in the soil e.g. temperature, moisture, PH and organic matter. So, to change some of these factors in a trial to control geoparasites transmission but with keeping the environment should be tried. These results also open the way to further studies to highlight the mutual affection between inhabitants of these sites and the prevalence of these geoparasites.

THE EFFECT OF STEM CELLS AS AN ADJUVANT ON THE IMMUNOGENICITY OF A POTENTIAL ANTI-SCHISTOSOMAL VACCINE IN MICE.

Vaccination against schistosomes can be targeted towards the prevention of infection and/or to the reduction of parasite fecundity and pathology. However, as eggs are responsible mainly for schistosomiasis pathology, so crude soluble egg antigen (SEA) seems suitable to be used as a potential vaccine. Many studies have provided new insights establishing a role for mesenchymal stem cells (MSCs) in liver regeneration and improvement of schistosomiasis hepatic fibrosis, in addition to the need for standardized and effective adjuvant-vaccine formulations. So, the aim of this work is to evaluate the effect of stem cells when used as an adjuvant of a potential anti-schistosomal vaccine (crude SEA) in murine models. The current work was carried out on 100 mice (30 males for harvesting MSCs + 70 females for seven study groups, each of 10). A schedule of vaccination and challenge infection was followed so, GI (control healthy), G2 (control infected only) infected subcutaneously with S. mansoni cercaria (80-90 Schistosoma mansoni cercariae suspended in 0.2 ml distilled Water), G 3 (FCA then infected) received Freund's complete adjuvant (FCA) then infected, G4 (MSCs then infected) received MSCs then infected, G5 (SEA then infected) received SEA vaccine then infected, G6 (SEA+FCA then infected) received SEA vaccine and FCA then infected, G7 (SEA+MSCs then infected) received SEA vaccine and MSCs then infected. The current work was assessed by histopathological study and morphometric analysis (using H&E and Masson's Trichrome stains) to highlight number, size and type of liver granulomas and percentage of liver fibrosis, immunological and molecular studies (RNA extraction, Re- verse Transcriptase and PCR technique) for detection of interleukin-10 mRNA gene expression in liver tissue by reverse transcriptase & polymerase chain reaction (RT & PCR). The results showed that a- SEA alone as a potential anti-schistosomal vaccine was more or less moderately protective, b- MSCs alone before the infection had mild prophylactic effects, c- MSCs as an adjuvant of the crude SEA increased its capabilities with highly significant results regarding the decrease in granuloma number, size, percentage and density of hepatic fi- brosis, and d-There was significant increase in IL-10 mRNA gene expression on using (SEA+MSCs) (G7) if compared to other tested groups.