• Parasites, Hosts and Diseases
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• v.35 no.2
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• pp.139-142
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• 1997

Cleaving host immunoglobulins is a well known mechanism of evading host immune reactions exploited by helminth parasites, Secreted cysteine proteases of helminth are a part of enzymes cleaving host IgG. Porogonimw westemani produces at least six different species of the cysteine protease in its developmental stages. This study was undertaken to evaluate comparatively the activities against human IgG by the different enzymes. When the metacercariae, which secrete 27 and 28 kDa cysteine proteases, were incubated in human IgG solution, IgG was degraded at its hinge region. Further incubation resulted complete hydrolysis. From 4-week and 7-week old juveniles and 16-week old adults of p. westemani, five different enzymes at 15, 17. 27 28 and 53 kDa have been purified, if the enzyme with the same molecular mass is regarded to be identical. In cleaving human IgG, each cysteine protease exhibited decreasing activities with age.

• Clinical and Experimental Reproductive Medicine
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• v.16 no.2
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• pp.153-160
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• 1989

The effect of antisperm antibodies (ASA) on the human in vitro fertilization (lVF) process was evaluated by analyzing the IVF data between October and December 1988 at Seoul National University Hospital prospectively. The immunobead test (IBT) was used to identify Ig G, Ig A, and Ig M in the serum, semen, and follicular fluid from 93 couples undergoing in vitro fertilization-embryo transfer (lVF-ET ) . The fertilization rate in couples with ASA to sperm head of at least one isotype in female serum (n= 10) was significantly less than that in couples without ASA to sperm head (n=83; 28.5% versus 45.3% , p=0.028). The presence of ASA to sperm head in follicular fluid (n=8) also reduced fertilization rate from 45.3% to 24.4% (p=O.0l3). However, ASA binding to sperm head in male serum and semen did not predict fertilization. Similarly, ASA binding to sperm tail and tail-tip did not reduced the oocyte fertilization rate significantly in any of the fluids tested. The zygote cleavage rate was not reduced in the presence of ASA. These results suggest that the presence of ASA to sperm head in female serum and follicular fluid is associated with reduced fertilization in IVF-ET. Another observation is that the oocyte that do fertilize in the presence of antisperm antibodies can subsequently proceed with normal cleavage. The results of this investigation therefore suggest that the IBT is a useful test forscreening of women participat.ing IVF-ET program.

• BMB Reports
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• v.43 no.8
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• pp.541-546
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• 2010

We utilized a mammalian expression system to purify and characterize autotaxin (ATX)/lysophospholipase D, an enzyme present in the blood responsible for biosynthesis of lysophosphatidic acid. The human ATX cDNA encoding amino acids 29-915 was cloned downstream of a secretion signal of CD5. At the carboxyl terminus was a thrombin cleavage site followed by the constant domain (Fc) of IgG to facilitate protein purification. The ATX-Fc fusion protein was expressed in HEK293 cells and isolated from conditioned medium of a stable clone by affinity chromatography with Protein A sepharose followed by cleavage with thrombin. The untagged ATX protein was further purified to essential homogeneity by gel filtration chromatography with a yield of approximately 5 mg/liter medium. The purified ATX protein was enzymatically active and biologically functional, offering a useful tool for further biological and structural studies of this important enzyme.

• Journal of Life Science
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• v.20 no.4
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• pp.503-510
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• 2010

Most allergens have protease activities, suggesting that proteases may be a key link between Th2-type immune reactions in allergic responses. Protease activated receptor (PAR) 2 is activated via the proteolytic cleavage of its N-terminal domain by proteinases. To know the role of PAR2 in Aspergillus protease allergen activated Th2 immune responses in airway epithelial cells, we investigated and compared immune cell recruitment and level of chemokines and cytokines between PAR2 knock out (KO) mice and wild type (WT) mice. There were evident immune cell infiltrations into the bronchial alveolar lavage fluid (BALF) of WT mice, but the infiltrations in PAR2 KO mice were significantly lowered than those of WT mice. The IL-25, TSLP, and eotaxin gene expressions were profoundly increased after Aspergillus protease, but their expression was significantly lowered in PAR2 KO mice in this study. Compared to PAR2 KO mice, OVA specific IgE concentrations in serum of WT mice were quite increased; moreover, the IgE level of PAR2 KO mice was lower than in WT mice. The IL-25 expression by Aspergillus protease stimulation was significantly reduced by p38 specific inhibitor treatment. In this study, we determined that Th2 response was initiated with IL-25 and TSLP mRNA up-regulation in lung epithelial cells via PAR2 after Aspergillus protease allergen treatment.

• KSBB Journal
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• v.22 no.4
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• pp.234-238
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• 2007

We used electrospary ionization ion trap tandem mass spectrometry (ESI-IT tandem MS) to structural elucidation of three different biantennary-type glycans having zero, one, two galactoses (G0, G1, G2). The highest fragment ion in the MS/MS spectra of three glycans was produced by 0,2-ring cleavage of fucose-linked N-acetylglucosamine (GlcNAc) in reducing end. The fragment ions both from precursor ions and 0,2-ring cleaved ions ($^{0.2}An$; n=5 for G0, n=6 for G1 and G2) were not overlapped each other. As results of $MS^n$ analyses, tandem fragmentation trees of each glycans were generated and 2,4-ring cleavages ($^{2.4}A_6$) were occurred in GlcNAc linked to reducing end GlcNAc. This structural elucidation and fragmentation study of N-linked glycans by tandem mass spectrometry can be applied to structural analysis of more complicated glycans.