الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 157 |  |  |
| | | from | 157 | | |
Abstract
its products are closely associated with outbreaks of human trichinellosis (144,112). The global prevalence of trichinellosis is difficult to be evaluated, but about 11 million people may be infected (1). It has been reported in 55 countries all over the world (26). The yearly total number of clinical trichinellosis was estimated to be 10000 cases with a death rate of 0.2% in the main 55 countries where trichinellosis occurs (4).
The disease has an acute or early phase (EP), comprising the intestinal (or enteral) phase and the subsequent migration of larvae to the blood vessels, in which clinical manifestations start with non specific signs and symptoms such as fever, myalgia, migraine, eyelid or facial edema, gastrointestinal disorders and eosinophilia (5). chronic trichinellosis has been reported during the chronic infection or late phase (LP) in which signs and symptoms include diffuse myalgia, paralysis-like state, periorbital and/or facial edema, conjunctivitis, fever, headache, skin rash, difficulties in swallowing or in opening the mouth, insomnia, weight loss, peripheral nerve sensations, hot flashes, coryza, hoarseness, bronchitis, splinter hemorrhages of the nail beds and/or the retinae, visual disturbances and paralysis of the ocular muscles (32,42).
The drugs most commonly used for treating human trichinellosis are benzimidazole derivatives (i.e. albendazole, flubendazole, mebendazole, and thiabendazole) (10). It has been shown that these drugs are apparently unable to kill encapsulating larvae (larvae in an advanced stage of development) (11,114). The effectiveness of albendazole is influenced by several key factors, such as oral bioavailability, which mainly depends on the solubility, dosage of therapy, host biotransformation, selectivity patterns as well as time of onset of treatment after infection (12).
Excretory-secretory (ES) proteins released by Trichinella are either extracted from adult worms or muscle larvae. The ES proteins of T. spiralis come mainly from the excretory granules and cuticles. They are directly exposed to the host’s immune system and are the main target antigens which induce the immune responses (6,2,113).
Immunization with these ES proteins elicited humoral immune response. Also, it induced a concurrent Th1/ Th2 local and systemic responses that are protective and at the same time they may help balancing the strong Th2 response triggered by helminth infections (1).
ES antigens and surface antigens are directly exposed to the host’s immune system which interferes with the invasion and development process of Trichinella larvae. The invasion of intestinal epithelia by T. spiralis larvae can be inhibited by immunization with surface or ES antigens (8,9).
This study aimed to evaluate the protective and the therapeutic effects of Trichinella excretory/secretory (ES) proteins on enteral and migratory phase of infection in Trichinella spiralis infected mice.
Summary and Conlusion
123
In the present study, 140 Swiss female albino mice were used and they were divided into seven groups in separate cages as follows:-
group I (Control group): 20 mice non infected non vaccinated and non-treated. Each mouse received 0.2 ml physiological saline solution.
group II (Infected control group): 20 mice infected non vaccinated and non-treated. Each mouse received 300 T. spiralis infective larvae.
group III: 20 mice vaccinated with AW/ES antigen. Each mouse was injected subcutanously by 100 μg of AW/ES antigen in PBS 7 days before oral infection with 300 T. spiralis muscle larvae (102).
group IV: 20 mice vaccinated with larval ES antigen. Each mouse was injected subcutanously by 100 μg of larval ES antigen in PBS 7 days before oral infection with 300 T. spiralis muscle larvae (102).
group V: 20 mice infected as above and treated with AW/ES antigen. Each mouse was intraperitoneally injected daily with 25 μg of AW/ES for 7 days starting from the first day of infection (83).
group VI: 20 mice infected as above and treated with larval ES antigen. Each mouse was intraperitoneally injected daily with 25 μg of ES for 7 days starting from the first day of infection (83).
group VII: 20 mice infected as above and treated with albendazole. Each mouse was treated orally with 50 mg/kg/day starting from the first day of infection for three successive days (103).
Each group in this study was further subdivided according to the time of sacrifaction into 2 equal subgroups (10 mice each):
Ten mice were sacrificed at the 8th day post infection (dpi) to assess the effect of vaccines and drugs on the adult worm in the small intestine.
Ten mice were sacrificed at the 35th dpi to assess the effect of vaccines and drugs on encysted larvae.
Evaluation was done by a parasitological, histopathological, immunological, immunohistochemical and molecular studies.
The present study showed that:
Concerning the adult count of T.spiralis in vaccinated groups in the present study, the highest percent of adult worm reduction (91.6%) was recorded in mice of group IV which received vaccine of larval ES, then group III that was vaccinated with AW/ES antigen (83.7%), with a statistically significance difference between both vaccinated groups (P3 < 0.005*) (Table 1).
Concerning the adult count of T.spiralis in treated groups in the present study, a higher percentage of adult worm reduction (96.6%) was detected in albendazole treated group (GVII) than those in mice treated with either larval ES antigen (GVI) (86.9%) or AW/ES antigen (GV) (80.1 %). There were statistically high significant differences between albendazole treated group and both groups treated with ES (P8& P9 <0.001**). Also, a statistically significant difference was noticed between both groups treated with ES (P7 ≤ 0.05*) (Table 2).
Summary and Conlusion
124
Regarding larval count of vaccinated groups, a higher percentage of Trichinella spiralis larval count reduction was achieved in mice vaccinated with larval ES antigen (GIV) (96.1%) than in mice vaccinated with AW/ES antigen (GIII) (68.2%) with a statistically significant difference between both vaccinated groups (GIII& GIV) (P3<0.05*) (Table 4).
Concerning larval count in treated groups, the highest percentage of reduction of total larval count was recorded by larval ES antigen (GVI) (87.96%), followed by mice treated with albendazole (GVII) which showed a lower reduction rate (64.8%) then, those treated with AW/ES antigen(GV) (63.5%). High statistical significant differences were noticed between larval ES antigen treated group (GVI) and other treated groups (GV& GVII) (P7 <0.001**& P9 <0.001**), but no statistically significant difference between AW/ES antigens treated group and albendazole treated group (P8 >0.05) (Table 5).
Concerning histopathological examination of intestine of the vaccinated groups in the present study, it showed that the lowest intensity of inflammation was noticed in mice vaccinated with larval ES antigen (GIV), where there were 3 mice out of 10 recorded +2 score (30%) and 7 mice out of 10 recorded +1 (70%). On the other hand, mice vaccinated with AW/ES antigen (GIII) showed a higher score of inflammation as one mice out of ten recorded +3 score (10%), three mice recorded +2 score (30%) and six mice recorded +1 (60%) with no statistically significant difference between both vaccinated group (G III& G IV) (P3>0.05) (Table 7).
In the current study, histopathological examination of intestine of treated groups showed that the lowest intensity of inflammation was noticed in albendazole treated group (GVII) as one mice out of ten recorded +2 score (10%) and nine mice out of ten recorded +1 (90%). However, mice treated with larval ES antigen (GVI), showed that 4 mice out of 10 recorded +2 score (40%) and 6 mice out of 10 recorded +1 (60%). On the other hand, mice treated with AW/ES (GV) showed a higher score of inflammation as one mice out of ten recorded +3 score (10%), 4 mice recorded +2 score (40%) and 5 mice recorded +1 (50%) with statistically significant difference between group VII and group V (P8<0.05*), but without significant difference between group VII and group VI (P9>0.05) and also no significant difference between both ES treated groups (P7>0.05) (Table 8).
Comparing larval deposition in muscular tissues of the vaccinated groups, the lowest intensity of larval deposition in muscular tissue was noticed in mice vaccinated with larval ES antigen (GIV), as two mice out of ten recorded +2 score (20%) and eight mice recorded +1 (80%). However, those vaccinated with AW/ES antigen (GIII) showed a higher score of larval deposition as four mice out of ten recorded +2 score (40%) and six mice recorded +1 (60%), with highly significant difference between the infected group and both vaccinated groups (G III& G IV) (Table 10).
Regarding larval deposition in muscular tissues of treated groups, the lowest intensity of larval deposition in muscular tissue was noticed in mice treated with larval ES antigen (GVI) as two mice out of ten recorded +2 score (20%) and eight mice recorded +1 (80%). Then, those treated with albendazole (GVII) as one mice out of ten recorded +3 score (10%), four mice recorded +2 score (40%) and five mice recorded +1 (50%) with statistically significant difference with group VI (P9 < 0.05*). However, mice treated with AW/ES antigen (GV) showed that two mice out of ten recorded +3
Summary and Conlusion
125
score (20%), three mice recorded +2 score (30%) and five mice recorded +1 (50%) without statistically significant difference with group VII (P8>0.05) but with statistically significant difference wih group VI (P7 < 0.05*) (Table 11).
In the present study, the highest serum IgG OD value (0.69±0.094) was recorded in mice vaccinated with larval ES antigen(G IV), then those vaccinated with AW/ES antigen (G III) (0.5760±0.11) with a statistically significant difference between both vaccinated groups (P3 ≤0.05*). However, infected mice achieved the lowest serum IgG level (0.1950±0.074) with also statistically significant difference when compared with vaccinated groups (P1& P2 <0.001**) (Table 13).
Regarding serum IgG OD value of treated groups, the highest serum IgG OD value was recorded in mice treated with larval ES antigen (G VI) (0.39±0.056) followed by those treated with AW/ES antigen (GV) (0.29±0.06) then albendazole treated mice (VII) (0.15±0.045). There were statistically significant differences between group VI and both of group V (P8 < 0.001**) and group VII (P9 < 0.001**) (Table 14).
Concerning immunohistochemical studies in the current work, the highest intensity of FoxP3 expression was recorded in infected control mice (GII) (136±9.66), while, those vaccinated with AW/ES antigen (GIII), showed a significant reduction of FoxP3 expression (25±6.7) with a significant difference between that group and group II (P1< 0.001**). In group vaccinated with larval ES antigen (GIV), the lowest FoxP3 expression was reported (10±0) with a highly statistically significant difference in comparison with GII and GIII (P2 <0.001** & P3 <0.001**) respectively (Table 16).
In the current study, the highest intensity of FoxP3 expression (H-Score) was recorded in infected non– treated mice (GII) (136±9.66), while those treated with AW/ES antigen (GV) showed a significant reduction of FoxP3 expression (58±9.2) with a significant difference in comparison with GII (P4<0.001**). In group VII, mice treated with albendazole, achieved a significant reduction of FoxP3 expression (37.5±2.6) with a significant difference in comparison with GII and GV (P6<0.001** & P8<0.001**). Larval ES treated mice (GVI) reported the lowest FoxP3 expression (11.5±2.4) with a significant difference in comparison with GII, GV and VII (P5<0.001**& P7<0.001** & P9<0.001**) (Table 17).
In the present study, according to the value of cycle threshold recorded by Real time PCR which is indirectly propotional to the DNA concentration ,there were statistically significant reduction of T.spiralis larval DNA concentration in vaccinated groups(GIII &GIV) in comparison with the infected control group(GII) (P1<0.001** & P2<0.001**). The highest value of cycle threshold was reported in mice vaccinated with larval ES protein (GIV) (35.6± 1.32) while in those vaccinated with adult ES protein (GIII) the cycle threshold value was (29.95±0.00) with a statistically significant difference between both vaccinated groups (P3<0.001**). The lowest value of cycle threshold reported in infected mice (GII) (4.17±0.007). (Table 19).
Concerning treated groups, the lowest value of cycle threshold was reported in infected mice (GII) (4.17±0.007), while the highest value was reported in those treated with larval ES protein (GVI) (30.8±0.042) with a highly statistically significant difference between both groups (P5<0.001**). In mice treated with albendazole (GVII), the cycle threshold value was (23.57±0.013) however; those treated with adult ES antigen (GV) recorded 15.2± 0.08. There were statistically significant reductions of T.
Summary and Conlusion
126
spiralis larval DNA concentrations in treated groups (GV &GVII) in comparison with the infected non treated group (GII) (P4<0.001** & P6<0.001**) (Table 20).