Most of the drugs used for trichinellosis treatment showed a limited bioavailability, a high degree of resistance and a weak activity against encapsulated larvae. Therefore, there is an urgent need to develop new agents to improve the bioavailability of these drugs. So, the aim of the present study was to assess the use of chitosan (CH) nanoparticles alone or loaded with full and half dose albendazole (ABZ) to increase albendazole dissolution rate, to enhance its antiparasitic activity during the muscular phases of T. spiralis infection. Fifty male albino mice were used. They were divided into six experimental groups. Two control groups each includes five mice and four infected treated groups each includes ten mice. Chitosan nanoparticles were used orally at a dose of 100mg/kg/day starting from the 31 st -day post infection (dpi) for seven successive days either alone or loaded with full dose or half dose of ABZ. Results revealed a significant improvement in all treated groups with the highest reduction rate (97.3%) of muscle larval counts, improvement of muscular histopathological changes, and degeneration of encysted larvae with minimal pathologic changes of infected skeletal muscles. A significant decrease in inducible nitric oxide synthetize (iNOS) expression in muscle tissues was in mice treated by CH loaded with a full dose of ABZ compared to control group.

No abstract

The tegument of schistosomes is a source of many potential anti-Schistosoma vaccine molecules. This work aimed to assess the protective effects of the adult Schistosoma mansoni tegument treated (TT) with sub-curative praziquantel (PZQ), whether in vivo (in vivo TT) or in vitro (in vitro TT), in murine schistosomiasis. In vitro TT and in vivo TT showed great similarity, and they differed from untreated tegument antigen (Teg) in terms of quantity and quality of protein bands on SDS–PAGE. Two immunization trials were performed, each with 50 mice, divided randomly into five groups of 10 mice each: (1) uninfected control mice (UC), (2) infected mice given phosphate buffer saline + adjuvant (PBS + adjuvant), (3) infected, Teg vaccinated, (4) infected, in vivo TT vaccinated, and (5) infected, in vitro TT vaccinated. All the immunizations with antigens induced mixed Th1/Th2 immune responses, as indicated by significantly high (P < 0.001) specific IgG2a and IgG1 levels, with Th1 predominating, as shown by a diminished IgG1/IgG2a ratio, as well as a high serum concentration of IFN-γ, an absence of IL-4 and increased IL-10. In vitro TT gave the most pronounced response. With respect to reduction of total worm burden, relative to PBS + adjuvant mice, in vitro TT achieved the highest significant (P < 0.001) results, followed by in vivo TT and Teg (51.8–57.04%, 44.6–50.2% and 35.2–39.3%, respectively). In scanning electron microscopy studies, all the tested antigens caused tegumental changes in adult worms, with the worst occurring with in vitro TT, such as retracted ventral sucker, an effect on the gynaecophoric canal, and changes to tubercles. In conclusion, in vitro TT, which is cheap to prepare, could be a potential vaccine against S. mansoni.

No abstract

No abstract