• Parasites, Hosts and Diseases
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• v.39 no.3
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• pp.233-240
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• 2001

Although some reports have been published on the protective effect of antibodies to Toxoplasma gondii surface membrane proteins, few address the inhibitory activity of antibodies to dense granular proteins (GRA proteins) . Therefore, we performed a series of experiments to evaluate the inhibitory effects of monoclonal antibodies (mAbs) to GRA proteins (GRA2, 28 kDa; GRA6, 32 kDa) and surface membrane protein (SAGI, 30 kDa) on the invasion of T. gondii tachyzoites. Passive immunization of mice with one of three mAbs following challenge with a lethal dose of tachyzoites significantly increased survival compared with results for mice treated with control ascites. The survival times of mice challenged with tachyzoties pretreated with anti-GRA6 or anti-SAG 1 mAb were significantly increased. Mice that received tachyzoties pretreated with both mAb and complement had longer survival times than those that received tachyzoites pretreated with mAb alone. Invasion of tachyzoites into fibroblasts and macrophages was significantly inhibited in the anti-GRA2, anti-GRA6 or anti-SAG 1 mAb pretreated group. Pretreatment with mAb and complement inhibited invasion of tachyzoites in both fibroblasts and macrophages. These results suggest that specific antibodies to dense-granule molecules may be useful for controlling infection with T. gondii.

• Korean Journal of Food Science and Technology
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• v.34 no.2
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• pp.290-295
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• 2002

Among 12 lactic acid bacteria examined for their abilities to activate the complement system by hemolytic complement assay $(TCH_{50})$, Lactobacillus plantarum previously isolated from Kimchi showed high anti-complementary activity. The anti-complementary activity of the cell wall fraction of L. plantarum was more potent than that of the cytosol fraction, and both activities showed dose dependency. These high activities of the cytosol and the cell wall fractions were relatively resistant to the digestion with pronase, but sharply decreased after the treatment of $NaIO_4$. These results suggested that the complement activation by the cytosol and the cell wall fractions was mainly due to their polysaccharides. By the cross-immunoelectrophoresis using anti-human C3, the C3 activation products from both fractions were identified in $Ca^{++}$-free condition. Anti-complementary activity $(ITCH_{50})$ of the cell wall fraction was retained under the same condition, whereas that of the cytosol fraction was reduced considerably. From these results, it was inferred that the mode of complement activation by the cell wall fraction was mainly via alternative pathway, and that of the cytosol fraction was via both alternative and classical pathways.

• BMB Reports
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• v.36 no.2
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• pp.230-236
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• 2003

Hot water-soluble crude polysaccharide (HCAP-0) that was obtained from the fruits of Capsicum annuum showed potent anti-complementary activity. The activity was unchanged by pronase digestion, but decreased by periodate oxidation. The HCAP-0 was fractionated by DEAE ion-exchange chromatography to give two major fractions, HCAP-II and III. These two fractions were finally purified by gel filtration to give HCAP-IIa, HCAP-IIIa1, and IIIa2 fractions that had high anti-complementary activities. The HCAP-IIIa1 and IIIa2 consisted of homogeneous polysaccharides. The anti-complementary activities were unaffected by treatment with polymyxin B, indicating that the modes of complement activation were not due to preexisting lipopolysaccharide. The molecular weight and sugar content of HCAP-IIIa2 had potent anti-complementary activity. The highest yields were 55 kDa and 75.9%, and the molar ratio of galactose (Ara:Gal, 1.0:4.6) was higher than other sugars. The crossed immuno-electrophoresis showed that both classical and alternative pathways were activated by HCAP-IIIa2.

• BMB Reports
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• v.48 no.1
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• pp.36-41
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• 2015

Recently, we demonstrated that human serum amyloid P component (SAP) specifically recognizes exposed bacterial peptidoglycan (PGN) of wall teichoic acid (WTA)-deficient Staphylococcus aureus ${\Delta}$tagO mutant cells and then induces complement-independent phagocytosis. In our preliminary experiments, we found the existence of human serum immunoglobulins that recognize S. aureus PGN (anti-PGNIgGs), which may be involved in complement-dependent opsonophagocytosis against infected S. aureus cells. We assumed that purified serum anti-PGN-IgGs and S. aureus ${\Delta}$tagO mutant cells are good tools to study the molecular mechanism of anti-PGN-IgG-mediated phagocytosis. Therefore, we tried to identify the intracellular molecule(s) that is involved in the anti-PGN-IgG-mediated phagocytosis using purified human serum anti-PGN-IgGs and different S. aureus mutant cells. Here, we show that anti-PGN-IgG-mediated phagocytosis in phorbol myristate acetate-treated U937 cells is mediated by $Ca^{2+}$ release from intracellular $Ca^{2+}$ stores and anti-PGN-IgGdependent $Ca^{2+}$ mobilization is controlled via a phospholipase C${\gamma}$-2-mediated pathway.

• Journal of Microbiology and Biotechnology
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• v.10 no.2
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• pp.267-271
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• 2000

Abstract Two glucans (PONGa and PONGb) differing in their anomeric and glycosidic linkage structures were isolated from the water-insoluble materials (PON) of Pleurotus ostreatus basidiocarps, which activated the complement system and were almost soley composed of D-glucose. The isolatIon was achieved by repeated precipitations with ethanol and adsorption on concanavalin A (Con A) of paN suspension in thymol/NaCL Based on methylation analysis. IR, GLC-MS, $^1H,{\;}and{\;}^{13}C-NMR$ spectroscopies, PONGa was found to be a branched a-glucan composed of ${\alpha}-linked$ D-glucopyranose residues and ${\alpha}-linked$ units with 6-branching points, whereas PONGb was a linear ${\beta}-1,3-glucan$ composed mainly of ${\beta}-1,3-linked$ D-glucopyranose residues. The PONGb particles reacted more potently than the PONGa particles as C3 activator in alternative complement hemolysis and crossed-immunoelectrophoresis using anti-human C3, thereby suggesting that the complement activating components of PON were ${\beta}-(13)-glucans rather$ than ${\alpha}-glucan$ components.onents.

• Journal of Microbiology and Biotechnology
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• v.9 no.4
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• pp.450-456
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• 1999

A high molecular-weight water-soluble fraction(PO) obtained by the ethanol precipitation of 0.1 N NaOH extracts of the mushroom Pleurotus ostreatus showed 82% anti-complementary activity for complement consumption hemolysis. The PO consisted of 42% carbohydrate (w/w), 50% protein (w/w), and 3% uronic acid (w/w). Fifty-eight percent of the anti-complementary activity decreased by periodate oxidation and 22% by protease digestion, suggesting that the sugar and protein moieties are essential for this activity. Two polysaccharide fractions, PO-IIIa-1 and PO-IIIa-2, with anti-complementary activity were isolated from the PO using DEAE-Sepharose FF followed by Sephadex G-75 and Sepharose CL-6B gel permeation chromatographies. The PO-IIIa-2 was found by HPLC to be nearly homogeneous, with the molecular mass of 531 kDa, and showed 96% $ITCH_{50}$ (inhibition against the total complement hemolysis of deionized water as the control) at a concentration of 1 mg/ml. This fraction contained galactose, mannose, fucose, and glucose with molar ratios of 1.75:1:0.65 and 0.59, respectively. The majority of galactose and mannose units in the PO-IIIa-2 were composed of TGalp1 ->, ->6Galp1->, ->2,6Galp1->, and ->Manp1->. The PO-IIIa-1 (molecular mass of 2000 kDa), exhibiting higher activity than the PO-IIIa-2, was further purified into two fractions, unbound proteoglycan (PO-IIIa-1A) and bound glucomannan (PO-IIIa-lB), by affinity chromatography using ConA-Sepharose CL-4B. The anti-complementary activity of each affinity purified fraction decreased as compared to that of the native PO-IIIa-1 fraction, indicating that the formation of complex between both polysaccharide fractions was necessary for full anti-complementary activity.

• Childhood Kidney Diseases
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• v.17 no.1
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• pp.1-5
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• 2013

C3 glomerulonephritis (C3GN) is a recently described entity that shows a glomerulonephritis on light microscopy, bright C3 staining and the absence of C1q, C4, and immunoglobulins on immunofluorescence microscopy and mesangial and/or subendothelial electron-dense deposits on electron microscopy. The term 'C3 glomerulopathy' is often used to include C3GN and dense deposit disease (DDD), CFHR5 nephropathy, those of which result from dysregulation of the alternative pathway of complement. C3GN shares some aspects of atypical hemolytic uremic syndrome, MPGN, late stage of post infectious glomerulonephritis and other glomerulonephrtis. When C3GN is considered, measurement of serum complement proteins including C3, CFH, CFI, CFB and testing for the presence of C3 nephritic factor, anti-factor H autoantibodies are necessary. To screening for mutations, genes that encode complement regulators should be evaluated. This disorder equally affected all ages, both genders, and typically presented with hematuria and proteinuria. In both the short and long term, renal function remained stable in the majority of patients.

• Applied Biological Chemistry
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• v.35 no.1
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• pp.42-50
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• 1992

We conducted screening on Chinese medicinal herbs to examine their anti-complementary activity by hemolytic complementary assay $(TCH_{50})$. Among 55 kinds of herbs, several herbs showed relatively potent anti-complementary activity which decreased $TCH_{50}$, more than 70% in comparison with control. Then, hot water extracts of the following herbs, Curcuma aromatica, Areca catechu, Gleditsiae spina, Euonymus alata, Acanthopanax senticous. Lonicera japonica, Aconitum carmichaeli, Curcuma zedoaria and Cinnamoum cassia, which were shown relatively potent anti-complementary activity were partially purified and analyzed their chemical properties. These activities were resistant to digestion with pronase but decreased by treatment with $NaIO_4$. These results may indicate that the complement activating ability in their herbs is due to polysaccharide. Furthermore, the anti-complementary activity of Areca catechu which was showed the most potent activity, was reduced partially in the absence of the $Ca^{++}\;ion$. After incubation of the normal human serum with partially purified polysaccharide of A. catechu in the absence of $Ca^{++}\;ion$, a cleavage of C3 in the serum was found to have occurred through immunoelectrophoresis using rabbit anti-human C3 serum. These results indicate that the mode of complement activation by polysaccharide of A. catechu is via both the alternative and classical pathway.

• Journal of the Korean Wood Science and Technology
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• v.20 no.4
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• pp.73-84
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• 1992

It was observed that the hot-water extract of the bark of Kalopanax pictus N. had the highest anti-complementary activity among the 11 kinds of forest materials. Methanol-and ethanol-soluble portions had low anti-complementary activities, but crude polysaccharide. HKP-0 had a high activity of 80%. HKP-0 contained 54.8% of total sugar and 27.9% of protein. The neutral sugars of HKP-0 consisted of mainly arabinose, galactose and glucose. HKP-4 fraction obtained by cetavlon treatment of HKP-0 showed the highest anti-complementary activity of 90%. The activity was not changed by pronase digestion bu decreased greatly by periodate oxidation. HKP-4 consisted of mainly arabinose and glucose with molar ratio of 1.0 : 22.4, HKP-4-I, an unabsorbed fraction from HKP-4 on DEAE Sepharose CL-6B column showed higher yield and activity than those of absorbed fractions. HKP-4-I was homogeneous, and its molecular weight was about 25,000. HKP-4-I contained 84.0% of neutral sugar and consisted of arabinose and glucose with molar ratio of 1.0 : 11.2. The anti-complementary activity of HKP-4-I was not decreased by the treatment of polymyxin B, and the polysaccharide activated both classical and alternative pathway in complement system. Void volume fraction obtained from HKP-4-I hydrolyzed with ${\alpha}$-amylase on Sephadex G-25 column only had a high anti-complementary activity.

• The Korean Journal of Zoology
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• v.34 no.2
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• pp.228-231
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• 1991

The phenotyping of the sixth complement component (C6) was performed on plasma or serum samples from 383 unrelated Korean, by IEF and immunoblotting using anti-human C6 serum. Three common allotypes, C6 A, C6 B and C6 B2 and two rare allotypes, C6 Ml and C6 Mu were observed. The allele frequencies of C6*A, C6*B and C6*B2 were estimated to be 0.4399, 0.5144, 0.0392, respectively. These frequencies are similar to those of the Eastasian populations.