• Parasites, Hosts and Diseases
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• 제40권2호
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• pp.89-92
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• 2002

The cysteine proteases of Paragonimus westermani metacercariae are involved in metacercarial excystment, host immune modulation, and possibly in tissue penetration. In order to clarify the origin of the enzymes, 28 and 27 kDa cysteine proteases in metacercarial excretory-secretory products were purified through the FPLC system using Mono Q column chromatography. The polyclonal antibodies to the enzymes were produced in BALB/c mice. Immunolocalization studies revealed that both cysteine proteases were distributed at the linings of excretory bladder and excretory concretions of the metacercariae. It was suggested that the excretory epithelium of P. westermani undertake the secretory function of metacercarial cysteine proteases, in addition to its role as a route for eliminating waste products.

• Parasites, Hosts and Diseases
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• 제60권5호
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• pp.357-360
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• 2022

Excretory-secretory products (ESP) of T. vaginalis have been shown to inhibit sperm motility, viability, and functional integrity, leading to a decreased fertilization rate in vitro. This study investigated whether T. vaginalis induce apoptosis and ultrastructural changes of sperm using flow cytometry and electron microscopy. Incubation of sperm with T. vaginalis ESP increased phosphatidylserine externalization and DNA fragmentation, and decreased mitochondrial membrane potential. Transmission electron microscopy of sperm incubated with ESP revealed abnormal features such as distorted heads, broken necks, and acrosomes exocytosis. This is the first report that demonstrates a direct impact of T. vaginalis ESP on sperm apoptosis and architecture in vitro.

• Parasites, Hosts and Diseases
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• 제47권1호
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• pp.65-68
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• 2009

Excretory-secretory products of Toxocara canis larvae have been considered as a major functional antigen in immune responses against toxocariasis. We studied ultrastructural localization of T. canis second-stage larval antigen using a seropositive human serum under immunogold electron microscopy. High-density gold particles were observed in the secretory cells, excretory duct, intestinal epithelium, and cuticle of the larval worm sections. The distribution of the positive reactions in the larval worms suggests that the nature of the antigen is excretory-secretory antigen including waste metabolites and secretory enzymes.

• 대한수의학회지
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• 제44권3호
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• pp.455-462
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• 2004

Change in ${\beta}$-tubulin nucleic acid and protein sequences was the only known difference between Haemonchus contortus fenbendazole (FBZ)-resistant and -susceptible isolates. This change was sufficient to determine the pathologic effect induced by FBZ treatment. This research was initiated to investigate further differences from these two isolates. Since ${\beta}$-tubulin is involved in formation of microtubule, which has functions in secretory vesicle transport, DNase activities from excretory/secretory products (ESP) of the two isolates were compared, based on pH, sensitivity to DNase inhibitors, molecular masses and production of 3'-OH. The most significant difference detected was that a 38.5 kDa DNase activity was identified from ESP of H. contortus FBZ-susceptible isolates but not from those of H. contortus FBZ-resistant isolates. However, it was shown that the 38.5 kDa DNase is expressed with similar level of activity in intestine and whole worm of H. contortus FBZ-resistant and -susceptible isolates. This result demonstrated that the secretory transport pathway of the 38.5 kDa DNase was inhibited by unknown mechanisms, which may be related with ${\beta}$-tubulin sequence change in FBZ-resistant isolates. Other DNases of 34, 36 and 37 kDa were detected from ESP of both H. contortus FBZ-resistant and -susceptible isolates. Overall DNase activities found from ESP of these two isolates were not inhibited by 10 mM EDTA at pH 5.0, but largely inhibited by pH 7.0. In addition, DNase activities in two isolates produced DNA fragments with mixtures of 3'- hydroxyls (OH) and 3'-phosphates (P) at each pH although the 3'-end labeling ratios at pH 5.0 and 7.0 were shown different. Identification of inhibition of the 38.5 kDa DNase secretion in FBZ-resistant isolates suggests existence of further differences, in addition to ${\beta}$-tubulin sequence change, in two isolates. This shows complex effect of FBZ on H. contortus biological mechanisms.

• Parasites, Hosts and Diseases
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• 제54권5호
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• pp.679-684
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• 2016

Clonorchiasis, caused by direct contact with Clonorchis sinensis worms and their excretory-secretory products (ESPs), is associated with chronic inflammation, malignant changes in bile ducts, and even cholangiocarcinogenesis. Our previous report revealed that intracellular free radicals enzymatically generated by C. sinensis ESPs cause NF-${\kappa}B$-mediated inflammation in human cholangiocarcinoma cells (HuCCT1). Therefore, the present study was conducted to examine the role of upstream Toll-like receptors (TLRs) on the initial host innate immune responses to infection. We found that treatment of HuCCT1 cells with native ESPs induced changes in TLR mRNA levels in a time-dependent manner, concomitant with the generation of free radicals. ESP-mediated free radical generation was markedly attenuated by preincubation of the cells with TLR1-4-neutralizing antibodies, indicating that at least TLR1 through 4 participate in stimulation of the host innate immune responses. These findings indicate that free radicals triggered by ESPs are critically involved in TLR signal transduction. Continuous signaling by this pathway may function in initiating C. sinensis infection-associated inflammation cascades, a detrimental event leading to progression to more severe hepatobiliary diseases.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1995년도 한국생물과학협회 학술발표대회
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• pp.288.2-288
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• 1995

No Abstract, See Full Text

• Parasites, Hosts and Diseases
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• 제46권3호
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• pp.127-132
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• 2008

Clonorchis sinensis is one of the most prevalent parasitic helminths in Korea. Although cholangiocarcinoma can be induced by C. sinensis infection, the underlying mechanism is not clearly understood. To assess the role of C. sinensis infection in carcinogenesis, an in vitro system was established using the human epithelial cell line HEK293T. In cells exposed to the excretory/secretory products (ESP) of C. sinensis and the carcinogen dimethylnitrosamine (DMN), cellular proliferation and the proportion of cells in the G2/M phase increased. Moreover, the expression of the cell cycle proteins E2F1, p-pRb, and cyclin B was dramatically increased when ESP and DMN were added together. Similarly, the transcription factor E2F1 showed its highest level of activity when ESP and DMN were added simultaneously. These findings indicate that DMN and ESP synergistically affect the regulation of cell cycle-related proteins. Our results suggest that exposure to C. sinensis and a small amount of a carcinogen such as DMN can promote carcinogenesis in the bile duct epithelium via uncontrolled cellular proliferation and the upregulation of cell cycle-related proteins.

• Parasites, Hosts and Diseases
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• 제57권4호
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• pp.379-387
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• 2019

Clonorchis sinensis is a carcinogenic human liver fluke that promotes hepatic inflammatory environments via direct contact or through their excretory-secretory products (ESPs), subsequently leading to cholangitis, periductal fibrosis, liver cirrhosis, and even cholangiocarcinoma (CCA). This study was conducted to examine the host inflammatory responses to C. sinensis ESPs and their putative protein components selected from C. sinensis expressed sequenced tag (EST) pool databases, including $TGF-{\beta}$ receptor interacting protein 1(CsTRIP1), legumain (CsLeg), and growth factor binding protein 2 (CsGrb2). Treatment of CCA cells (HuCCT1) with the ESPs or bacterial recombinant C. sinensis proteins differentially promoted the secretion of proinflammatory cytokines ($IL-1{\beta}$, IL-6, and $TNF-{\alpha}$) as well as anti-inflammatory cytokines (IL-10, $TGF-{\beta}1$, and $TGF-{\beta}2$) in a time-dependent manner. In particular, recombinant C. sinensis protein treatment resulted in increase (at maximum) of ~7-fold in $TGF-{\beta}1$, ~30-fold in $TGF-{\beta}2$, and ~3-fold in $TNF-{\alpha}$ compared with the increase produced by ESPs, indicating that CsTrip1, CsLeg, and CsGrb2 function as strong inducers for secretion of these cytokines in host cells. These results suggest that C. sinensis ESPs contribute to the immunopathological response in host cells, leading to clonorchiasis-associated hepatobiliary abnormalities of greater severity.

• 한국어병학회지
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• 제27권1호
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• pp.25-33
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• 2014

Anisakis simplex sensu stricto와 A. pegreffii의 3기 유충과 4기 유충에서 얻은 excretory-secretory (ES) products 및 somatic extracts의 가수분해효소 활성을 API ZYM kit를 이용하여 비교하였다. Esterase 그룹의 가수분해효소 중 acid phosphatase는 A. simplex (s.s.)와 A. pegreffii 모두에서 높은 활성을 나타냈으며, esterase (C 4)의 경우 somatic extracts에서만 가수분해효소 활성이 나타났는데 A. simplex (s.s.)가 A. pegreffii와 비교하여 3기와 4기 유충 모두에서 2배 가량 높은 활성을 나타냈다. alkaline phosphatase, acid phosphatase 그리고 naphthol-AS-BI-phosphohydrolase의 경우 A. simplex (s.s.)와 A. pegreffii 모두 3기 유충보다 4기 유충에서 더 높은 가수분해효소 활성이 확인되었다. Aminopeptidase 그룹의 가수분해효소 활성은 leucine arylamidase에서 관찰되었는데, somatic extracts의 경우 A. pegreffii 보다 A. simplex (s.s.)에서 가수분해 효소 활성이 두 배 가량 높게 확인되었으며, 대부분의 다른 효소들에서는 활성이 거의 나타나지 않았다. Glycosidase 그룹의 가수분해효소 활성은 N-acetyl-${\beta}$-glucosaminidase, ${\alpha}$-mannosidase 그리고 ${\alpha}$-fucosidase에서 확인되었는데, A. simplex (s.s.) 보다 A. pegreffii에서 높은 가수분해효소 활성을 확인할 수 있었으며, 대부분 4기 유충보다 3기 유충에서 더 높은 가수분해효소 활성이 확인되었다. 이러한 아니사키스속 선충의 종과 유충단계에 따른 가수분해 효소의 활성 차이는 선충의 성장, 탈피, 소화, 섭이 등의 대사과정의 차이에 기인한 것으로 생각된다.

• Parasites, Hosts and Diseases
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• 제43권1호
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• pp.33-37
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• 2005

Eosinophil degranulation is considered to be a key effector function for the killing of helminthic worms and tissue inflammation at worm-infected lesion sites. However, relatively little data are available with regard to eosinophil response after stimulation with worm-secreted products which contain a large quantity of cysteine proteases. In this study, we attempted to determine whether the degranulation of human eosinophils could be induced by the direct stimulation of the excretory-secretory products (ESP) of Paragonimus westermani, which causes pulmonary paragonimiasis in human beings. Incubation of eosinophils for 3 hr with Paragonimus-secreted products resulted in marked degranulation, as evidenced by the release of eosinophil-derived neurotoxin (EON) in the culture supernatants. Moreover, superoxide anion was produced by eosinophils after stimulation of the ESP. The ESP-induced EDN release was found to be significantly inhibited when the ESP was pretreated with protease inhibitor cocktail or the cysteine protease inhibitor, E-64. These findings suggest that human eosinophils become degranulated in response to P. westermani-secreted proteases, which may contribute to in vivo tissue inflammation around the worms.