الفهرس 
Chapter 1: Review of literatureOnly 14 pages are availabe for public view
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Abstract
Trichinellosis is a parasitic infection caused by Trichinella spiralis (T. spiralis), which is a serious parasitic zoonosis and a globally endemic disease. Human infection is commonly the result of eating raw or undercooked pork meat containing Trichinella larvae. The frequent outbreaks of human trichinellosis globally underscore the need to develop an effective vaccine. Different vaccines have been developed against T. spiralis such as whole worm extract, excretory- secretory antigen, recombinant DNA vaccine and proteases vaccines.
Trichinella spiralis cathepsin B proteins appear to be promising targets for vaccine development. Secretory cathepsin B protease is a major papain-like cysteine protease which plays key roles in parasite survival, host invasion and host immune response, so it can be used as a good vaccine targets. It was reported that treatment with a recombinant T. spiralis cathepsin B-like protein (TsCBP) induces a T-helper2 (Th2) response in Trichinella spiralis infected mice.
Nanotechnology plays a central role in the recent technological advances in the areas of disease diagnosis, drug design and delivery. Nanovaccines have efficient loading capacity, excellent biocompatibility and suitable size for antigen-based immunotherapy nanoparticle-based systems which provide an advantageous tool for vaccine delivery due to their unique physiochemical properties.
Antibodies (IgG1, IgM and IgA) have a significant role against Trichinella infection through entrapment and rapid expulsion of infective first stage rhabditiform larvae (L1 larvae), reducing adult worm fecundity and participating in killing of newborn larvae.
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Adjuvants have the ability of modulation of cellular and humeral immune responses without inducing local or general reactions, which have been widely used in different vaccines.
Anti-helminthic drugs such as mebendazole and albendazole are commonly used in treatment but none was fully effective against the encysted T. spiralis or the newborn larvae. So, there was a great need to develop new safe antihelminthic therapy to treat.
This work aimed to study the protective and therapeutic effects of cathepsin B protein and cathepsin B protein carried on nano-liposomes with/or without aluminium hydroxide as adjuvat in murine trichinellosis.
This experimental study began in March 2021 and was completed in July 2022. It was conducted at Theodore Bilharz Research Institute in Medical Parasitology labolatories (Giza, Egypt) and Faculty of Medicine, Menoufia University in central labolatory and Histology laboratories.
This study was performed on 110 swiss female albino mice weighing an average 25 ± 0.2 gram, with controlled temperature and humidity conditions (25 °C; 70%). The mice were obtained from Theodore Bilharz Research Institute (Giza, Egypt) and were maintained according to the National Guidelines for Experimental Animal Welfare.
Mice were classified into three main groups; group I (control group), group II (vaccinated group) and group III (treated group). Each group was divided into subgroups consisting of ten mice each as shown below:
All subgroups were equally divided into two groups according to sacrifaction:
1. The 1st subgroup was sacrified on 8th day post infection (dpi) to assess intestinal phase of trichinellosis (subgroups; Ia1, Ib1, IIa1, IIb1, IIc1, IId1, IIIa1, IIIb1, IIIc1, IIId1 and IIIe1).
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2. The 2nd subgroup on 35th day p.i to assess muscular phase. Sacrifaction was done by cervical dislocation (subgroups; Ia2, Ib2, IIa2, IIb2, IIc2, IId2, IIIa2, IIIb2, IIIc2, IIId2 and IIIe2).
The present study showed that:
I. Parasitological results:
A significant reduction of T. spiralis adult worm count was recorded in all vaccinated and treated subgroups as compared to infected subgroup. Table (4) shows that the vaccinated subgroups GIIa1, GIIb1, GIIc1& GIId1 showed the best reduction rate; 56%, 74.4%, 59.6% & 77.2% respectively in comparison with treated subgroups GIIIa1, GIIIb1, GIIIc1& GIIId1 which showed reduction rate; 31.97%, 47.83%, 53.29% & 69.29% respectively. There was statically significant differences between vaccinated and treated subgroups.
Larval count; table (5) shows that the vaccinated subgroups GIIa2, GIIb2, GIIc2& GIId2 showed the best reduction rate; 34.9%, 68.5%, 56.8% & 73.8% respectively in comparison with treated subgroups GIIIa2, GIIIb2, GIIIc2& GIIId2 which showed reduction rate; 21.5%, 65.7%, 41.8% & 89.7% respectively. There was statically significant differences between vaccinated and treated subgroups.
II. Histopathological results:
In intestinal phase, the lowest intensity of inflammation and lowest intensity of crypt destruction were in GIId1 (vaccinated with liposome-TsCBPA with aluminium hydroxide), while the highest intensity of inflammatory cells was in GIIa1 (vaccinated with TsCBPA) and GIIIa1 (treated with TsCBPA).
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In muscular phase; the lowest degree of inflammation and improvement, lowest degree of degeneration of surrounding muscle fiber, the highest degree of capsule thinning and highest degree of degradation of internal structure of larva were in GIId2 (vaccinated with liposome-TsCBPA with aluminium hydroxide), while the lowest improvement was in GIIIe2 (treated with Albendazole (drug control).
III. Immunological results:
In intestinal and muscular phases, the highest level of antibodies (IgG1 and IgM) and the lowest level of serum antigen were in groups vaccinated/treated with liposome-TsCBPA with aluminium hydroxide followed by groups vaccinated/treated with liposome-TsCBPA.
IV. Molecular results:
In intestinal and muscular phases, the highest level of cycle threshold (lowest larval DNA in tissues) were in groups vaccinated/treated with liposome-TsCBPA with aluminium hydroxide followed by groups vaccinated/treated with liposome-TsCBPA.