• 생명과학회지
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• 제5권1호
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• pp.20-25
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• 1995

기생충감영시 cytokine으로 활성화된 대식세포가 방어기전의 Effector cell로 작용할 때 분비하는 nitric oxide의 양 및 TNF-$\alpha$ 와 IFN-$\gamma$의 분비정도와 nitric oxide와의 상관관계 등을 알아보기 위하여 3종의 흡충류, Fasciola, paragonimus, Schistosma의 조항원 (100mg/ml)을 마우스 복강내에 주사　 후 24시간, 72시간, 9일간격으로 마우스의 대식세포(1X10$^{6}$/ml)를 분리하여 RPMI 배지 (10% FCS 첨가)에서 48시간 배양후 Nitric TNF-$\alpha$ 및 IFN-$\gamma$를 ELISA로 정량하여 다음과 같은 결과를 얻었다. Nitrite 생성정도는 Fasciola 조항원으로 24시간 감작시킨 대식세포에서 가장 높게 나타났으며 (140$\mu$M/ml) Paragonimus 항원군에서는 24시간에 최고치에 달하였다가(34 $\mu$M/ml) 시간이 경과함에 따라 점차 감소하였다. IFN-$\gamma$는 Paragonimus 항원군에서만 대조군에 비해 높았으며 9일경에 최고치를 보였다(475ng/ml). TNF-$\alpha$는 Schistosoma 항원군에서는 nitric oxide의 생성과 분비 양상이 일치하였다. 위의 결과에 의하면, 흡충류항원으로 감작된 마우스 대식세포의 nitric oxide 생성에 영향을 미치는 cytokine의 종류는 흥충류에 따라 차이를 보였으며, 이 중 Paragonimus 항원에 의해서는 IFN-$\gamma$의 분비가 촉진되는 것으로 나타났고, Schistosoma 의 경우에는 TNF-$\alpha$가 nitric oxide의 생성에 관계함을 알 수 있었다.

• Parasites, Hosts and Diseases
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• 제50권1호
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• pp.37-43
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• 2012

Although schistosomicidal drugs and other control measures exist, the advent of an efficacious vaccine remains the most potentially powerful means for controlling this disease. In this study, native fatty acid binding protein (FABP) from $Fasciola$ $gigantica$ was purified from the adult worm's crude extract by saturation with ammonium sulphate followed by separation on DEAE-Sephadex A-50 anion exchange chromatography and gel filtration using Sephacryl HR-100, respectively. CD1 mice were immunized with the purified, native $F.$ $gigantica$ FABP in Freund's adjuvant and challenged subcutaneously with 120 $Schistosoma$ $mansoni$ cercariae. Immunization of CD1 mice with $F.$ $gigantica$ FABP has induced heterologous protection against $S.$ $mansoni$, evidenced by the significant reduction in mean worm burden (72.3%), liver and intestinal egg counts (81.3% and 80.8%, respectively), and hepatic granuloma counts (42%). Also, it elicited mixed $IgG_1/IgG_{2b}$ immune responses with predominant $IgG_1$ isotype, suggesting that native $F.$ $gigantica$ FABP is mediated by a mixed Th1/Th2 response. However, it failed to induce any significant differences in the oogram pattern or in the mean granuloma diameter. This indicated that native $F.$ $gigantica$ FABP could be a promising vaccine candidate against $S.$ $mansoni$ infection.

• Parasites, Hosts and Diseases
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• 제52권2호
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• pp.151-162
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• 2014

The technique of stem cells or hepatocytes transplantation has recently improved in order to bridge the time before whole-organ liver transplantation. In the present study, unfractionated bone marrow stem cells (BMSCs) were harvested from the tibial and femoral marrow compartments of male mice, which were cultured in Dulbecco's modified Eagle's medium (DMEM) with and without hepatocyte growth factor (HGF), and then transplanted into Schistosoma mansoni- infected female mice on their 8th week post-infection. Mice were sacrificed monthly until the third month of bone marrow transplantation, serum was collected, and albumin concentration, ALT, AST, and alkaline phosphatase (ALP) activities were assayed. On the other hand, immunohistopathological and immunohistochemical changes of granuloma size and number, collagen content, and cells expressing OV-6 were detected for identification of liver fibrosis. BMSCs were shown to differentiate into hepatocyte-like cells. Serum ALT, AST, and ALP were markedly reduced in the group of mice treated with BMSCs than in the untreated control group. Also, granuloma showed a marked decrease in size and number as compared to the BMSCs untreated group. Collagen content showed marked decrease after the third month of treatment with BMSCs. On the other hand, the expression of OV-6 increased detecting the presence of newly formed hepatocytes after BMSCs treatment. BMSCs with or without HGF infusion significantly enhanced hepatic regeneration in S. mansoni-induced fibrotic liver model and have pathologic and immunohistopathologic therapeutic effects. Also, this new therapeutic trend could generate new hepatocytes to improve the overall liver functions.

• Parasites, Hosts and Diseases
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• 제55권1호
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• pp.21-29
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• 2017

Schistosoma haematobium is a biocarcinogen of human urinary bladder (UB). The present study investigated developing UB cancer mouse model by injecting S. haematobium eggs into the bladder wall and introduction of chemical carcinogens. Histopathological findings showed mild hyperplasia to epithelial vacuolar change, and high grade dysplasia. Squamous metaplasia was observed in the S. haematobium eggs+NDMA group at week 12 but not in other groups. Immunohistochemistry revealed significantly high expression of Ki-67 in urothelial epithelial cells of the S. haematobium eggs+BBN group at week 20. The qRT-PCR showed high expression of p53 gene in S. haematobium eggs group at week 4 and S. haematobium eggs+BBN group at week 20. E-cadherin and vimentin showed contrasting expression in S. haematobium eggs+BBN group. Such inverse expression of E-cadherin and vimentin may indicate epithelial mesenchymal transition in the UB tissue. In conclusion, S. haematobium eggs and nitrosamines may transform UB cells into squamous metaplasia and dysplasia in correlation with increased expression of Ki-67. Marked decrease in E-cadherin and increase in p53 and vimentin expressions may support the transformation. The present study introduces a promising modified animal model for UB cancer study using S. haematobium eggs.

• Parasites, Hosts and Diseases
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• 제51권2호
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• pp.165-175
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• 2013

The fear that schistosomes will become resistant to praziquantel (PZQ) motivates the search for alternatives to treat schistosomiasis. The antimalarials quinine (QN) and halofantrine (HF) possess moderate antischistosomal properties. The major metabolic pathway of QN and HF is through cytochrome P450 (CYP) 3A4. Accordingly, this study investigates the effects of CYP3A4 inhibitor, ketoconazole (KTZ), on the antischistosomal potential of these quinolines against Schistosoma mansoni infection by evaluating parasitological, histopathological, and biochemical parameters. Mice were classified into 7 groups: uninfected untreated (I), infected untreated (II), infected treated orally with PZQ (1,000 mg/kg) (III), QN (400 mg/kg) (IV), KTZ (10 mg/kg)+QN as group IV (V), HF (400 mg/kg) (VI), and KTZ (as group V)+HF (as group VI) (VII). KTZ plus QN or HF produced more inhibition (P<0.05) in hepatic CYP450 (85.7% and 83.8%) and CYT b5 (75.5% and 73.5%) activities, respectively, than in groups treated with QN or HF alone. This was accompanied with more reduction in female (89.0% and 79.3%), total worms (81.4% and 70.3%), and eggs burden (hepatic; 83.8%, 66.0% and intestinal; 68%, 64.5%), respectively, and encountering the granulomatous reaction to parasite eggs trapped in the liver. QN and HF significantly (P<0.05) elevated malondialdehyde levels when used alone or with KTZ. Meanwhile, KTZ plus QN or HF restored serum levels of ALT, albumin, and reduced hepatic glutathione (KTZ+HF) to their control values. KTZ enhanced the therapeutic antischistosomal potential of QN and HF over each drug alone. Moreover, the effect of KTZ+QN was more evident than KTZ+HF.

• Parasites, Hosts and Diseases
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• 제51권2호
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• pp.155-163
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• 2013

This study aimed to evaluate the efficacy of fructose-1,6-bis phosphate aldolase (SMALDO) DNA vaccination against Schistosoma mansoni infection using different routes of injection. The SMALDO has been cloned into the eukaryotic expression vector pcDNA3.1/V5-His TOPO-TA and was used in injecting Swiss albino mice intramuscularly (IM), subcutaneously (SC), or intraperitoneally (IP) ($50{\mu}g/mouse$). Mice vaccinated with non-recombinant pcDNA3.1 served as controls. Each group was immunized 4 times at weeks 0, 2, 4, and 6. Two weeks after the last booster dose, all mice groups were infected with 80 S. mansoni cercariae via tail immersion. At week 8 post-infection, animals were sacrificed for assessment of parasitological and histopathological parameters. High anti-SMALDO IgG antibody titers were detected in sera of all vaccinated groups (P<0.01) compared to the control group. Both the IP and SC vaccination routes resulted in a significant reduction in worm burden (46.2% and 28.9%, respectively, P<0.01). This was accompanied by a significant reduction in hepatic and intestinal egg counts (41.7% and 40.2%, respectively, P<0.01) in the IP group only. The number of dead eggs was significantly increased in both IP and IM groups (P<0.01). IP vaccination recorded the highest significant reduction in granuloma number and diameter (54.7% and 29.2%, respectively, P<0.01) and significant increase in dead miracidia (P<0.01). In conclusion, changing the injection route of SMALDO DNA vaccination significantly influenced the efficacy of vaccination. SMALDO DNA vaccination via IP route could be a promising protective and antipathology vaccine candidate against S. mansoni infection.

• Parasites, Hosts and Diseases
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• 제53권1호
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• pp.129-134
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• 2015

Schistosoma haematobium is one of the most prevalent parasitic flatworms, infecting over 112 million people in Africa. However, little is known about the genetic diversity of natural S. haematobium populations from the human host because of the inaccessible location of adult worms in the host. We used 4 microsatellite loci to genotype individually pooled S. haematobium eggs directly from each patient sampled at 4 endemic locations in Africa. We found that the average allele number of individuals from Mali was significantly higher than that from Nigeria. In addition, no significant difference in allelic composition was detected among the populations within Nigeria; however, the allelic composition was significantly different between Mali and Nigeria populations. This study demonstrated a high level of genetic variability of S. haematobium in the populations from Mali and Nigeria, the 2 major African endemic countries, suggesting that geographical population differentiation may occur in the regions.

• Parasites, Hosts and Diseases
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• 제55권5호
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• pp.533-540
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• 2017

Schistosoma mansoni is highly endemic in Tanzania and affects all age groups at different degrees. However, its control approach does not include adult individuals who are equally at risk and infected. To justify the inclusion of adult individuals in MDA programs in Tanzania, the present study focused on determining the prevalence of S. mansoni infection and its related morbidities among adult individuals. This was a cross sectional study conducted among 412 adult individuals aged 18-89 years living in selected villages of Rorya and Butiama districts located along the shoreline of the Lake Victoria. A pretested questionnaire was used to collect socio-demographic and socio-economic information of participants. Ultrasonographic examinations were conducted for all study participants using the Niamey protocol. A single stool sample was obtained from all study participants and examined for S. mansoni using the Kato-Katz technique. The study revealed a high prevalence of S. mansoni (56.3%), and the majority of infected individuals had a light intensity of infection. Ultrasonographic findings revealed that 22.4% of adult individuals had periportal fibrosis (PPF) (grade C-F), with 18.4% having grade C and D and 4% having grade E and F. Males had the highest prevalence of PPF (31.7% vs 10.8%, P<0.001). Organomegaly was common with 28.5% and 29.6% having splenomegaly and hepatomegaly, respectively. S. mansoni infection and its related morbidities included PPF, hepatomegaly, and splenomegaly were common among adult individuals. To reduce the level of transmission of S. mansoni infection, planned mass drug administration campaigns should include adult individuals living in these villages.

• BMB Reports
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• 제37권2호
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• pp.223-228
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• 2004

The levels of arylsulfatases A and B, $\alpha$-amylase, aspartate transcarbamylase, and $\gamma$-glutamyl transpeptidase were investigated during the infection of mice with schistosoma mansoni. This infection caused a significant (p<0.001) increase in the activity of hepatic arylsulfatase B (ASB), aspartate transcarbamylases and $\gamma$-glutamyl transpeptidase. A non-significant difference occurred for $\alpha$-amylase (p<0.3) and arylsulfatase A (p>0.5) when compared to the control. The specific activity of hepatic ASB was progressively increased with the progression of the Schistosoma-infection. Moreover, the kinetic studies of hepatic ASB in Schistosoma-infection showed that a slight decrease in the value of $K_m$ and about a 40% increase in $V_{max}$ when compared to the control. In addition, the pH optimum of hepatic ASB was altered from 6 to 7 as a result of schistosomiasis. These observations suggest that there are schistosomiasis-associated changes of the catalytic and kinetic properties of hepatic ASB.

• Parasites, Hosts and Diseases
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• 제36권1호
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• pp.55-58
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• 1998

라오스 남부의 메콩강 유역에서 위치한 Pakes 지역 주민의 장내 윤충류 감염 상황을 조사하였다. 대상 인원은 현지 보건소 직원 및 가족 등 성인 90명과 초등학교 학생 47명으로 모두 137명이었다. 검사방법으로는 Kato-Katz 셀로판후층도말법을 이용하였고, 1인당 1회 검사하였다. 검사 결과, 총 충란 양성률은 75.9%로 매우 높았고, 검출된 윤층은 Opisthorchis viverrini (평균 양성률 43.8%), 회충 (26.3%), 편충 (19.0%), 구충 (19.0%), 분선층 (2.2%), 유. 무구조충 (0.7%) 및 메콩주협흡충 (Schistosoma mekongi) (1.5%)이었다. O. viverrini 충란 양성자 3인으로부터 충체를 회수하고자 프라지콴텔로 치료하고 하제를 부여한 바 설사변에서 O. viverrini 성충 5, 10 및 395마리를 각각 회수할 수 있었다. 이상의 결과로 라오스의 Pakse 지역은 O. viverrini 및 토양매개성 윤충 감염이 농후하며, 메콩주혈흡충의 생활사가 이루어지고 있을 것으로 추측되었다.