• The Journal of the Korean Society for Microbiology
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• v.22 no.2
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• pp.147-153
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• 1987

Colonization factor antigen I(CFA I) has been shown to be one of several virulence factors that promote attachment of enterotoxigenic E. coli(ETEC) to small intestinal epithelial cells of humans. The ability of ETEC to produce mannose-resistant hemagglutination(MRHA) of human blood group A has been used to detect CFA I. To determine gastrointestinal carriage in Korean children of E. coli with MRHA and CFA I, 116 strains of E. coli from diarrheal children admitted to Hanyang University Hospital were examined for MRHA of human erythrocytes and the presence of CFA I. Of 45 ETEC strains, 18(40%) gave a positive MRHA($MRHA^+$) and eight(18%) were positive for CFA I(CFA $I^+$). ETEC with CFA I were all heat-stable enterotoxin(ST) producers and two of these strains were of serogroups $O_{25}$. Of 17 classic enteropathogenic E. coli(EPEC), 7(41%) were $MRHA^+$ but all were negative for CFA I(CFA $I^-$). Of 30 enteroadherent E. coli(EAEC) strains, 11(37%) were $MRHA^+$ and one was CFA $I^+$. Of 24 nonpathogenic E. coli, 4(17%) were $MRHA^+$ but all were CFA $I^-$. It was shown that MRHA was common in all strains of E. coli, CFA I was limited only to ST producing ETEC and EAEC; although MRHA is a useful screening procedure, serologic tests seem to be necessary to comfirm CFA I production. CFA I was associated with a lower proportion of ETEC isolates in Korea than has been reported for other locations.

• Korean Journal of Veterinary Research
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• v.61 no.2
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• pp.19.1-19.7
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• 2021

Feline panleukopenia virus (FPV) causes leukopenia and severe hemorrhagic diarrhea, killing 50% of naturally infected cats. Although intact FPV can serve as an antigen in the hemagglutination inhibition (HI) test, an accidental laboratory-mediated infection is concern. A non-infectious diagnostic reagent is required for the HI test. Here, we expressed the viral protein 2 (VP2) gene of the FPV strain currently prevalent in South Korea in a baculovirus expression system; VP2 protein was identified by an indirect immunofluorescence assay, electron microscopy (EM), Western blotting (WB), and a hemagglutination assay (HA). EM showed that the recombinant VP2 protein self-assembled to form virus-like particles. WB revealed that the recombinant VP2 was 65 kDa in size. The HA activity of the recombinant VP2 protein was very high at 1:2¹⁵. A total of 143 cat serum samples were tested using FPV (HI-FPV test) and the recombinant VP2 protein (HI-VP2 test) as HI antigens. The sensitivity, specificity, and accuracy of the HI-VP2 test were 99.3%, 88.9%, and 99.3%, respectively, compared to the HI-FPV test. The HI-VP2 and HI-FPV results correlated significantly (r = 0.978). Thus, recombinant VP2 can substitute for intact FPV as the serological diagnostic reagent of the HI test for FPV.

• YAKHAK HOEJI
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• v.36 no.5
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• pp.412-426
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• 1992

Effects of beta-carotene on the immunobiological responses were studied in ICR mice. ICR male mice were divided into 8 groups (10 mice/group), and beta-carotene at doses of 4, 20 and 100 mg/kg were orally administered to ICR mice once daily for 28 consecutive days. Cyclophosphamide (CY) was injected intraperitoneally (i.p.) to ICR mice with a single dose of 5 mg/kg body weight at 2 days before secondary immunization. Mice were sensitized and challenged with sheep red blood cells (5-RBC). Immune responses were evaluated by humoral immunity, cellular immunity and non-specific immunity. The results of this study were summarized as follows: (1) Beta-carotene significantly increased the weight ratios of liver, spleen and thymus to body weight depending on dose, and significantly increased the increasing rate of body weight and the number of circulating leukocyte. (2) Beta-carotene dose-dependently increased hemagglutination titer, Arthus reaction and hemolytic plaque forming cell related to humoral immunity. (3) Beta-carotene significantly increased delayed-type hypersensitivity reaction and rosette forming cell related to cellular immunity. (4) Beta-carotene dose-dependently increased phagocytic activity, and significantly increased natural killer (NK) cell activity. (5) Beta-carotene dose-dependently inhibited reductions in humoral immunity, cellular immunity, NK cell activity and phagocytic activity by treatment with CY.

• YAKHAK HOEJI
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• v.43 no.1
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• pp.48-54
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• 1999

Effects of zinc chloride (Zn) on the immune responses of lipopolysaccharide (LPS) were studied by using ICR mice. Mice were divided into 4 groups (10 mice/group), and Zn was given to the mice with i.p. injection at 0.3 mg/kg 5 times a week for 14 days, and 1 hr after Zn administration, LPS was given with i.p. injection at 5 mg/kg twice a week. Mice were immunized and challenged with sheep red blood cells (SRBC). Immunobiological responses were evaluated by humoral, cellular and nonspecific immunity. LPS treatment significantly increased the relative weights of spleen and thymus, hemagglutination titer (HA) and proliferation of splenocytes compared with those in controls, but significantly decreased the body weight gain. Zn treatment significantly increased proliferation of splenocytes and circulating leukocytes compared with those in controls. Combination of Zn and LPS significantly decreased the body weight gain and proliferation of splenocytes compared with those in controls. Combination of Zn and LPS significantly decreased HA and proliferation of splenocytes than in LPS alone. These findings indicate that zinc lowered the humoral immune responses of LPS.

• Journal of Life Science
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• v.24 no.6
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• pp.603-611
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• 2014

The lectins were separated from Korean and Chinese mung bean seeds finally via chromatography using Sephadex G-100 and their biochemical features were studied and compared. They showed no hemagglutination with human red blood cells regardless of trypsin treatment and showed hemagglutination with only trypsin treated rabbit red blood cells. The molecular weights of two lectins were identified as 54 kDa and 28 kDa by SDS-PAGE. It was found that while the optimal reaction temperature of the lectin from Korean mung bean was $60^{\circ}C$, that of the lectin from Chinese mung bean seeds was $50^{\circ}C$. It was found also that the most thermal stable temperature of the seed lectin from Korean mung bean seeds was $50^{\circ}C$ and the lectin from Chinese mung bean was $40-50^{\circ}C$. The lectin from Korean mung bean seeds showed the highest activity at pH 3.2 and the lectin from Chinese mung bean showed the highest activity at pH 6.2. It was identified that when treating a denaturant, thiourea and guanidine-HCl resulted in no hemagglutination, so they induced denaturalization. It was identified also that there was no hemagglutination with urea, so it did not induced denaturalization. They showed no septicity to 6 types of carbohydrates including D-glucose. In addition, the lectins from the two mung bean seed had specificity to metal ions.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.4
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• pp.334-340
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• 2005

Lectin is a cell-agglutinating and carbohydrate-binding protein present in many plants. The lectin of Canavalia ensiformis shoot with specific affinity for D-glucose was purified by affinity chromatography using Sephadex G-100, and some of its biochemical characterizations were studied. Lectin was purified 8.87-fold and exhibited final specific activity of 225.74 units/mg protein with a $2.3\%$ yield. SDS-PAGE analysis demonstrated that the purified shoot lectin exists as a tetramer of 102 kD, composed of two subunits with molecular weight of 29 and 22 kD. The purified lectin was observed to agglutinate rabbit blood cell. The optimal temperature for the activity of this lectin was $40^{\circ}C$, and this lectin was relatively stable to heat with the highest activity at $50{\~}60^{\circ}C$. The maximal activity was observed at pH 7.2.

• Journal of Microbiology and Biotechnology
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• v.9 no.5
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• pp.672-674
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• 1999

Cepacidine A was first identified as a novel antifungal antibiotic which was isolated from the culture broth of Pseudomonas cepacia AF200l. It showed a potent in vitro antifungal activity against various pathogenic fungi, but did not show any activity against bacteria. Recently, the immunosuppressive action of cepacidine A was discovered using an in vitro screening system involving inhibition of the proliferation of murine lymphocytes stimulated by 2 mitogens, and also by in vivo mouse models involving inhibition of delayed type hypersensitivity and SRBC hemagglutination. Cepacidine A showed a significant activity of cellular immunosuppression (ED/sub 50/) at concentration levels of 1-3 ㎎/㎏, i.p.. Unfortunately, the delayed toxicity at a dose of above 3 ㎎/㎏ i.p. was apparent.

• Journal of Life Science
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• v.18 no.3
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• pp.350-356
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• 2008

Biochemical characterization including hemagglutination of erythrocytes, molecular weight, optimum temperature, thermal stability, optimum pH, carbohydrate specificity, and inhibitory effect of metal ion were studied in lectin of eggplant (Solanum melongena L.) fruit prepared by ammonium sulfate fractionation and affinity chromatography. This lectin was agglutinated by trypsin-treated rat blood erythrocyte. The molecular weight of this lectin by SDS-PAGE was estimated to be approximately 19.3 kDa of a single band. This lectin has no activity by 7 carbohydrates containing D-glucose. The optimum range of temperature and pH were $10-20^{\circ}C$ and pH 6.2-7.2, respectively. This lectin was relatively stable at $20-70^{\circ}C$. And the activity of this lectin was not inhibited by $Ca^{2+},\;Co^{2+},\;Cu^{2+},\;Fe^{2+},\;Mg^{2+}$, and $Mn^{2+}$.

• Environmental Analysis Health and Toxicology
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• v.6 no.1_2
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• pp.59-70
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• 1991

This study was performed to investigate the effect of olive oil diet on the immune response in ICR male mice. Experimental diets of 4 groups were fed ad libitum to the ICR male mice for 27 days. The results of this study were summarized as followings: 1. 10% Olive oil diet group as compared with the control diet group significantly decreased liver weight rate but significantly increased hemagglutination titer (HA), Arthus reaction, delayed type reaction (DTH), rosette forming cell (RFC), and phagocyte activity. 2. 20% Olive oil hypersensitivity diet group as compared with the control diet group significantly increased body weight gain, liver weight rate, and HA but significantly decreased Arthus reaction, DTH, RFC, phagocyte activity, and peripheral circulating white blood cell (WBC). 3. 30% Olive oil diet group as compared with the control diet group significantly increased liver weight rate but significantly decreased body weight gain, Arthus reaction, plaque forming cell (PFC), DTH, RFC, phagocyte activity, and WBC. The results showed that the increase of olive oil doses significantly decreased humoral and cellular immune responses, phagocyte activity, and WBC.

• YAKHAK HOEJI
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• v.35 no.5
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• pp.401-415
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• 1991

Effects of quercetin on the specific and non-specific immune responses were studied in vivo. Quercetin at a dose of 2.5, 5, 10, 20 and 40 mg/kg were orally administered to ICR male mice once daily for 28 consecutive days. Cyclophosphamide was injected intraperitoneally to ICR mice with a single dose of 5 mg/kg 2 days before secondary immunization. Mice were sensitized and challenged with sheep red blood cells (S-RBC). Immune responses were evaluated by humoral and cellular immune reponses and non-specific immune response. The results of this study were summarized as followings; 1. Quercetin significantly decreased the body weight, and introduced the atrophy of liver, spleen and thymus gland dose-dependently, but increased the numbers of white blood cell. 2. Querectin significantly depressed the hemagglutination titer, Arthus reaction and hemolytic plaque forming cell. 3. Quercetin significantly depressed the delayed type hypersensitivity and rosette forming cell. 4. Quercetin at a dose of 2.5, 5 and 40 mg/kg significantly depressed phagocytic activity. 5. Quercetin at a dose of 10 and 20 mg/kg significantly increased natural killer cell activity.