• Parasites, Hosts and Diseases
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• v.38 no.2
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• pp.103-106
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• 2000

It is well known that the cysteine proteases in excretory-secretory product (ESP) of Paragonimus westermani newly excysted metacercariae (PwNEM) are capable of degrading IgG in vitro. Recent evidence suggests that the IgG-coated surface, such as found on parasites, is one of the most effective physiologic stimuli for granulocyte activation. Therefore, this study was designed to investigate the effect of excretory-secretory product (ESP) of PwNEM on superoxide production of granulocytes stimulated with IgG The 96-well plates were coated with human IgG (0, 10, 30, $100{\;}\mu\textrm{g}/ml$) in the absence or presence of ESP. When granulocytes were incubated in the wells coated with human IgG in the presence of ESP, the level of superoxide production of granulocytes was reduced to about 90% when compared to the cells incubated in the wells coated with IgG alone. This inhibitory effect of the ESP on IgG-induced superoxide production of granulocytes was concentration-dependent. These results suggest that ESP secreted by PwNEM may be important in the control of effector functions of granulocytes stimulated with IgG in human paragonimiasis.

• 한국전자현미경학회:학술대회논문집
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• 2007.05a
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• pp.75-78
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• 2007

The localization of cellulase were investigated in the capitate glandular trichomes of Pelargonium ${\times}$ fragransby a transmission electron microscopy. The secretory cells of capitate trichomes involved in biosynthesis and its secretion. Secretory material is transported to the space between the plasma membrane and cell wall, and subsequently accumulated in the secretory cavity. The splitting of secretory cell wall during the formation of secretory cavity is suggested that wall-forming enzymes, such as cellulase, may contribute to the wall separation process. Cellulase reaction product was localized in the secretory cell, the secretory cavity and in the subcuticular wall of glandular trichomes. Reaction products were present over fibrillar matrix in the secretory cavity associated with both the inner wall and the subcuticular wall.

• Animal cells and systems
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• v.6 no.4
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• pp.327-333
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• 2002

Among the silk glands in the black widow spider Latrodectus mactans, the ampullate one is the most predominant gland in both sexes, and is com-posed of three functional parts - excretory duct, storage ampulla and convoluted tail regions. This experiment was performed using mechanical pulling stimulation with electric motor equipment to reveal a correlation between silk usage and silk producing system in this poisonous spider. The mature secretory products in glandular epithelium are closely packed and appear as electron-opaque spherical vesicles. A part of the vesicles with fine fibrillar paracrystalline texture seems to store some proteins which will function at the time of final assembly into fibrils. Most of the secretory silk products which originated from the rough endoplasmic reticula of the glandular epithelial cells are grown by fusion with surrounding small vesi-cles. However, the Golgi complex does not seem to play an important role in this process of secretion. According to progressive maturation of secre-tory silk product, these granules are progressively filled with a fine fibrillar material, and thus appear much more electron-dense than those of earlier states. When the secretory product is extruded from the glandular cavity, the epithelium is rapidly changed to a thinner layer of tall columnar cells with less definitive cell membranes. After extruding there ave a few secre-tory droplets within these cells, thus causing this region to stain much lighter.

• Parasites, Hosts and Diseases
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• v.54 no.5
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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.

• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.4
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• pp.242-246
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• 2000

Human lipocortin-I was expressed as a secretory product by Saccharomyces cerevisiae harboring an expression system consisting of GAL10 promoter, inulinase signal sequence and lipocortin-I terminator. Fed-batch fermentation was carried out to overproduce recombinant human lipocortin-I. The culture medium was desalted and concentrated by ultrafiltration, and then subjected to hydroxyapatite column chromatography. The lipocortin-I was purified to >98% purity by single-step hydroxyapatite column chromato-graphy. However, it was found that the purified lipocortin-I was a proteolytically-cleaved form which was cleaved immediately after the basic amino acid Lys26.

• Parasites, Hosts and Diseases
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• v.30 no.3
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• pp.227-230
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• 1992

Spirometra mansoni plerocercoid (sparganum) was incubated in saline at $4^{\circ}C{\;}or{\;}37^{\circ}C$ up to 100 hours. Protein contests in the excretory$.$secretory product (ESP) were rather constant (mean 7.7 mg of protein/gram of sparganum) in the preparations. Reducing SDS-PAGE of ESP showed similar protein subunit compositions with those in crude extract. Antigenic 36 and 31 kDa Proteins were major bands in ESP. ESP exhibited specific activities of protease(2.9~5.3 units/mg) at pH 6.0 and pH 7.5. Presence of protease activity in ESP may be a supporting evidence that hitherto known cysteiRe protease of sparganum is possibly secreted.

• Journal of Applied Biological Chemistry
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• v.51 no.3
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• pp.136-138
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• 2008

• Biotechnology and Bioprocess Engineering:BBE
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• v.6 no.4
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• pp.306-308
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• 2001

A recombinant human growth hormone(hGH) was expressed as a secretory product in the yeast Saccharomyuces cerevisiae. There different leader sequences derived from the mating fac-tor $\alpha$1(MF$\alpha$1) inulinase and invertase were used to direct the secretion of hGH into the extracel-lular medium. Among three leader sequences tested, the inulinase leader sequence was found to be the most efficient in the secretory expression of hGH. In contrast, no hGH was detected in the ex-tracellular medium with the invertase leader sequence. After 48 h shake-flask culture, the yields of hGH secreted into th emedium by the invertase. MF$\alpha$1 inulinase and invertase leader sequences were approximately 0, 0.3 and 0.9 mg/L, respectively. The secretion efficiencies were also found to be 0, 3.8 and 13% for the invertase , MG$\alpha$1 and inulinase leader sequences, respectively.

• Applied Microscopy
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• v.28 no.4
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• pp.539-549
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• 1998

The silk glands of the spiders are of several types. Among the several types of spider's silk glands, the principal fibers used in constructing the eggcase are products of the tubuliform glands (TBG), which are present only in females. Development of these glands parallels maturations of the ovaries and fat bodies. In order to understand the mechanism of eggcase-silk production, this paper has examined the fine structural changes of the TBG during the period of egg maturation in the garden spider, Argiope aurentia. Between the two kinds of secretory granules observed in the glandular epithelium of the mature TBG, the electron-dense granules which have paracrystalline structure are revealed to be the precursors of the eggcase silk fibers. During the production of eggcase, rapid release of the secretory product occurs at apical surface by the mechanism of apocrine secretion. Moreover, secondary lysosomes appear due to the rapid disorganization of cellular components during the eggcase formation. Examinations of formed fibers indicate a multicomponent internal structure, and electron micrographs reveal each fiber contains numerous electron lucent fibrils embedded in an amorphous electron dense matrix. The secretory precursors are produced as separated vesicles via well-oriented rER, and no Golgi complex has been found in the glandular epithelial cells.

• Parasites, Hosts and Diseases
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• v.38 no.1
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• pp.17-23
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• 2000

Eosinophils are important effector cells in host defense against parasites. Excretory-secretory product (ESP) produced by helminthic worms plays important roles in the uptake of nutrients, migration in the host tissue, and in immune modulation. However little is known about the ability of the ESP to directly trigger eosinophil apoptosis. This study investigated whether the ESP of newly excysted metacercariae of Paragonimus westermani could induce apoptosis in human eosinophils. Apoptosis was assayed by staining the cells with FITC-annexin V, and the cells were analyzed by flow cytometry. It was found that the ESP of newly excysted metacercariae of P. westemani induced a direct time- and concentration-dependent increase in the rate of constitutive apoptosis in mature human eosinophils. Eosinophil apoptosis was first apparent 3 hr after treatment with the ESP and continued to increase after 6 hr of incubation with respect to the cells cultured in the absence of the ESP. While only 2.8% of the eosinophils incubated in the medium for 3 hr were apoptotic, 7.6%, 10.9% and 22.6% of the eosinophils treated with 10. 30 and $100{\;}\mu\textrm{g}/ml$ ESP were apoptotic, respectively. This result suggests that the ESP of newly excysted metacercariae of P. westermani directly induce eosinophil apoptosis, which may be important for the survival of the parasites and the reduction of eosinophilic inflammation in vivo.