• 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 Chest Surgery
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• v.19 no.4
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• pp.558-562
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• 1986

The extracorporeal circulation has been much improved recently, but has yet much complex problems such as the protein denaturation and the activation of the complement system by the exposure of the blood to the foreign surface, which may result in such as the postperfusion syndrome. We studied the changes of the plasma protein fractions by the electrophoresis and the complement consumption [C3, C4] by the immunodiffusion method in the patients undergoing cardiac operation from Mar. 1, 1986 to Aug. 31, 1986. The results were summarized as follows: 1. y-globulin fraction was decreased [p<0.02 by paired t-test, N=25], but a,-globulin was increased [p<0.001 by paired t test, N=25] after operation. 2. C3,C4 were significantly reduced [p<0.001 by paired t-test, N=14] postoperatively and normalized from 24 hours after operation. 3. The consumption of C3,C4 had significant linear correlation [correlation coefficient r=0.97] and C, was more markedly reduced comparing with C3, which probably means the complement activation by classical pathway in our bubble oxygenator group.

• Clinical and Experimental Pediatrics
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• v.52 no.6
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• pp.721-724
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• 2009

Meningococcal infections can be associated with abnormalities of the complement system, which contains 5 terminal complement proteins. Furthermore, deficiencies in 1 of these 5, complement component 7 (C7), leads to the loss of complement lytic function, and affected patients show increased susceptibility to recurrent meningococcal meningitis and systemic Neisseria gonorrhoeae infection. In September 2003, an 11-year-old female patient presented at our outpatient department with high fever, lower leg pain, headache, and petechiaes. She rapidly progressed to coma but later achieved full recovery due to prompt treatment. Her final diagnosis was meningococcal sepsis and arthritis. Her elder brother also had a similar bacterial meningoencephalitis history, which encouraged us to perform analyses for complement component and gene mutations. Resultantly, both the brother and sister were found to have the same mutation in the C7 gene. Subsequently, vaccinations of the meningococcal vaccine meningococcal vaccine ($Menomune^{(R)}$) were administered. However, in September 2006, the brother expired due to acute micrococcus meningoencephalitis. At present, the 16-year-old female patient is healthy. Here, we report a Korean family with a hereditary C7 deficiency with susceptibility to meningococcal infections due to C7 gene mutation.

• Childhood Kidney Diseases
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• v.23 no.2
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• pp.93-99
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• 2019

C3 glomerulopathy is a renal disorder involving dysregulation of alternative pathway complement activation. In most instances, a membranoproliferative pattern of glomerular injury with a prevalence of C3 deposition is observed by immunofluorescence microscopy. Dense deposit disease (DDD) and C3 glomerulonephritis (C3GN) are subclasses of C3 glomerulopathy that are distinguishable by electron microscopy. Highly electron-dense transformation of glomerular basement membrane is characteristic of DDD. C3GN should be differentiated from post-infectious glomerulonephritis and other immune complex-mediated glomerulonephritides showing C3 deposits.

• IMMUNE NETWORK
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• v.21 no.5
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• pp.36.1-36.16
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• 2021

Peroxiredoxins (Prxs) are ubiquitously expressed peroxidases that reduce hydrogen peroxide or alkyl peroxide production in cells. Prxs are released from cells in response to various stress conditions, and they function as damage-associated molecular pattern molecules. However, the secretory mechanism of Prxs and their roles have not been elucidated. Thus, we aimed to determine whether inflammasome activation is a secretory mechanism of Prxs and subsequently identify the effect of the secreted Prxs on activation of the classical complement pathway. Using J774A.1, a murine macrophage cell line, we demonstrated that NLRP3 inflammasome activation induces Prx1, Prx2, Prx5, and Prx6 secretion in a caspase-1 dependent manner. Using HEK293T cells with a transfection system, we revealed that the release of Prx1 and Prx2 relies on gasdermin-D (GSDMD)-mediated secretion. Next, we confirmed the binding of both Prx1 and Prx2 to C1q; however, only Prx2 could induce the C1q-mediated classical complement pathway activation. Collectively, our results suggest that inflammasome activation is a secretory mechanism of Prxs and that GSDMD is a mediator of their secretion. Moreover, secreted Prx1 and Prx2 bind with C1q, but only Prx2 mediates the classical complement pathway activation.

• Korean Journal of Food Science and Technology
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• v.34 no.5
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• pp.879-884
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• 2002

Cold and hot water fractions of Diospyros kaki were screened to determine its anti-complementary activity. Flour of Diospyros kaki leaf (250 g) was boiled at $100^{\circ}C$ for 3 h and passed through a membrane of 10 kDa molecular weight (DK-0). DK-0 was precipitated with ethanol and refluxed with methanol to obtain the crude polysaccharide (DKC). DKC-1 was isolated by ion exchange chromatography on DEAE-Toyopearl 650C, and DKC-1c was purified from DKC-1 by size exclusion chromatography on Bio gel P-60. The anti-complementary activities of DKC-1c at $1000\;{\mu}g/mL$ were 85.4 and 61.1% via whole and alternative pathways, respectively. DKC-1c was determined as a neutral polysaccharide composed of glucose (29.0 mol.%), arabinose (24.3 mol.%), and galactose (16.2 mol.%) with the molecular weight of 66.6 kDa. Results of agarose gel immunoelectrophoresis revealed DKC-1c, as a complement activator, cleaved C3 into C3a and C3b via both pathways.

• IMMUNE NETWORK
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• v.24 no.2
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• pp.17.1-17.16
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• 2024

We have reported that anterior cruciate ligament (ACL) injury leads to the differential dysregulation of the complement system in the synovium as compared to meniscus tear (MT) and proposed this as a mechanism for a greater post-injury prevalence of post traumatic osteoarthritis (PTOA). To explore additional roles of complement proteins and regulators, we determined the presence of decay-accelerating factor (DAF), C5b, and membrane attack complexes (MACs, C5b-9) in discarded surgical synovial tissue (DSST) collected during arthroscopic ACL reconstructive surgery, MT-related meniscectomy, osteoarthritis (OA)-related knee replacement surgery and normal controls. Multiplexed immunohistochemistry was used to detect and quantify complement proteins. To explore the involvement of body mass index (BMI), after these 2 injuries, we examined correlations among DAF, C5b, MAC and BMI. Using these approaches, we found that synovial cells after ACL injury expressed a significantly lower level of DAF as compared to MT (p<0.049). In contrast, C5b staining synovial cells were significantly higher after ACL injury (p<0.0009) and in OA DSST (p<0.039) compared to MT. Interestingly, there were significantly positive correlations between DAF & C5b (r=0.75, p<0.018) and DAF & C5b (r=0.64 p<0.022) after ACL injury and MT, respectively. The data support that DAF, which should normally dampen C5b deposition due to its regulatory activities on C3/C5 convertases, does not appear to exhibit that function in inflamed synovia following either ACL injury or MT. Ineffective DAF regulation may be an additional mechanism by which relatively uncontrolled complement activation damages tissue in these injury states.

• Development and Reproduction
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• v.17 no.4
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• pp.311-319
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• 2013

Fish larvae are immediately exposed to microbes from hatching to maturation of their lymphoid organs, therefore effective innate mechanisms is very important for survival in such an environment. The key component of innate immune system, C3 is central protein of all activation pathways of the complement system, leading to inflammatory reactions, such as opsonisation, chemotaxis, and cell lysis of pathogens. Although, innate mechanisms is essential for survival in the early stage of development, little is known about defence mechanisms. In this study, the alignment analysis showed that amino acid sequence of C3 from olive flounder liver EST homologous to other known C3 sequences with 73-99% identity. Also, we examined the tissue distribution of olive flounder C3 and analyzed expression pattern from the fertilized egg until 28 days post hatching. As a result, olive flounder C3 mRNA was expressed only in the liver and the mRNA level more increased as developmental proceed during the early stage. These results may suggest that olive flounder C3 plays an important function in the early immune response of olive flounder larvae.

• The Korean Journal of Physiology and Pharmacology
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• v.3 no.6
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• pp.579-586
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• 1999

Complement-mediated neutrophil activation has been hypothesized to be an important mechanism of reperfusion injury. It has been proposed that C1 esterase inhibitor (C1 INH) may prevent the complement- dependent activation of polymorphonuclear leukocytes (PMNs) that occurs within postischemic myocardium. Therefore, The effect of C1 INH was examined in neutrophil dependent isolated perfused rat heart model of ischemia (I) (20 min) and reperfusion (R) (45 min). Administration of C1 INH (5 mg/Kg) to I/R hearts in the presence of PMNs $(100{\times}10^6)$ and homologous plasma improved coronary flow and preserved cardiac contractile function (p＜0.001) in comparison to those I/R hearts receiving only vehicle. In addition, C1 INH significantly (p＜0.001) reduced PMN accumulation in the ischemic myocardium as evidenced by an attenuation in myeloperoxidase activity. These findings demonstrate the C1 INH is a potent and effective cardioprotective agent inhibits leukocyte-endothelial interaction and preserves cardiac contractile function and coronary perfusion following myocardial ischemia and reperfusion.

• Archives of Pharmacal Research
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• v.26 no.6
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• pp.463-465
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• 2003

Four protostane-type triterpenes, alisol B 23-acetate (1a), alisol C 23-acetate (2a), alisol B(3a), and alisol A 24-acetate (4a), were isolated from the rhizome of Alismatis plantago-aquatica L. var. orientale Samuelson (Alismataceae) and eleven protostane derivatives (compounds 1-11) were obtained by selective modification from alisol B 23-acetate (1a). These compounds were investigated for their anti-complement activity against the classical pathway of the complement system. Alisol B (3a) and alisol A 24-acetate (4a) exhibited anti-complement activity with $IC_{50} values of 150 and 130 \mu$ M. Among the synthetic derivatives, the tetrahydroxylated protostane triterpene (9) showed moderate inhibitory activity with $IC_{50} value of 97.1 \mu$ M. Introduction of an aldehyde group at C-23 (10; $IC_{50} value, 47.7 \mu$ M) showed the most potent inhibitory effect on the complement system in vitro.