• IMMUNE NETWORK
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• 제10권6호
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• pp.239-246
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• 2010

Background: Monoclonal antibodies (mAbs) recognizing Class III epitope of CD34 are essential for flow cytometric diagnosis of leukemia. Methods: 27H2 mAb was developed from a mouse alternatively immunized with human acute leukemia cell lines, KG1 and Molm-1. Using flow cytometric analysis of various leukemic cell lines and peripheral blood, immunohistochemical study of frozen tonsil, we characterized 27H2 mAb. Antigen immunoprecipitated with 27H2 mAb immunobloted with anti-CD34 mAb. A case of bone marrow sample of acute lymphoblastic leukemia (ALL) patient was obtained at CBNU Hospital. For epitope identification enzyme treatment with neuraminidase and O-sialoglycoprotein endopeptidase (OSGE) and blocking assay with known classIII mAb (HPCA-2) were done. Results: Only KG1 and Molm-1 revealed positive immunoreactivity. Immunohistochemical staining disclosed strong membranous immunoreactivity on high endothelial venules. Antigen immunoprecipitated by 27H2 mAb showed approximately 100 kDa sized band immunoblotted with anti-CD34 under non-reducing conditions. Epitope recognized by 27H2 mAb disclosed resistancy to both neuraminidase and OSGE treatment and completely blocked with known class III mAb preincubation. CD34 positive leukemic cells in BM of pre B cell ALL patient detected by FITC-conjugated 27H2 and HPCA-2 were identified with similar sensitivity. Conclusion: A novel murine mAb recognizing class III epitope of human CD34 with high affinity, which is useful for flow cytometric diagnosis of leukemia, was developed.

• 생명과학회지
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• 제28권5호
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• pp.555-562
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• 2018

Swine influenza virus (SIV)는 돼지 개체군에서 가장 흔한 질병을 일으키는 바이러스 중 하나이며 그 subtype은 hemagglutinin (HA)와 neuraminidase (NA)에 의해 결정됩니다. 최근 SIV subtype 진단 방법이 개발되고 있으나 SIV의 리보뉴클레오타이드 서열의 많은 변이로 인해 PCR 보다는 항원-항체 반응을 이용하는 방법이 주로 사용되고 있다. 본 연구에서는 SIV 하위 유형의 신속한 결정을 위하여 2008년 이후 국내에서 발생한 SIV의 다중염기서열 정렬을 통하여 10개의 subtype 진단 프라이머 세트를 개발하고 이를 이용한 one-step RT-PCR 반응을 최적화하였다. 또한 감염력이 높고 독성이 있는 인플루엔자 H1N1 (pH1N1)의 아형에서 확인된 독특한 M 유전자서열을 검출함으로써 pandemic SIV를 조기에 결정하도록 특이적 프라이머를 설계하였다. 2008년부터 2014년까지 한국에서 발생한 9종의 SIV RNA를 활용하여 SIV의 아형 및 pandemic 가능성을 결정하기 위해 시험 분석한 결과 모든 진단 프라이머 세트는 SIV 아형을 정확하게 결정하였으며 pandemic SIV를 검출할 수 있는 것으로 확인되었다. 결과적으로 이들 프라이머 세트를 이용한 최적화된 one-step RT-PCR 분석이 SIV 아형의 신속한 진단에 유용하다는 것이 확인하였다. 이러한 결과는 SIV 하위 유형 및 pandemic SIV가 확산되기 전에 조기 발견을 위한 키트로 개발될 수 있음을 시사한다.

• 한국동물위생학회지
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• 제25권3호
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• pp.245-257
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• 2002

The gene encoding the HN protein from the CBP-1 strain, a heat stable Newcastle disease virus (NDV) isolated from diseased pheasants in Korea, was characterized by reverse transcriptase- polymerase chain reaction(RT-PCR) and the nucleotide and amino acid sequences were analyzed following cloning of the HN gene. In all of the NDV strains studied, a 1.75 kb size cDNA fragment for the HN gene was generated by RT-PCR and smaller specific band sizes harboring the internal portions of the HN gene were also detected by using four pairs of primers. The RT-PCR was sensitive enough to detect viral transcripts when the virus titer was above 25 hemagglutination units. The amplified 1.75 kb cDNA was cloned into a BamHI site of the pVL1393 Baculo transfer vector. The nucleotide sequences of the 1,758 bp HN gene from the CBP-1 strain were determined by the dye terminator cyclic sequencing method. The gene sequences were compared among the strains of CBP-1, Texas GB, Beaudette C, LaSota, B1 and Ulster. The homology of the CBP-1 HN gene to other HN variants was 97.8% to Texas GB, 98.4% to Beaudette C, 95.4% to LaSota, 95.6% to B1 and 90.2% to Ulster. As the deduced 577 amino acid sequences were compared among the strains, the homology for CBP-1 HN appeared to be 96.7% to Texas GB, 97.9% to Beaudette C, 95.5% to LaSota, 95.5% to B1 and 92.7% to Ulster. It was evident that the amino acid sequences included 5 sites for N-asparagine linked glycosylation and 12 cysteine residues. The three conserved leucine residues within the predicted transmembrane domain of the HN protein are amino acid 30, 37 and 44. The three antigenic sites on the HN protein of NDV are amino acids 347(Glu), 481(Asn) and 495(Glu). These data indicate that the genotype of the CBP-1 strain is more closely associated with the strains of Texas GB and Beaudette C than it is for the LaSota, B1 and Ulster strains.

• 생명과학회지
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• 제33권8호
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• pp.605-611
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• 2023

최근에 재조합 H7Nx 인플루엔자 바이러스가 산발적으로 인체 감염 사례가 보고되고 있으며 이러한 바이러스는 조류 종으로부터 지속적으로 분리되고있다. 본 연구에서는 조류에서 유래된 H7N1 인플루엔자 바이러스를 분리하여 A/wild bird/South Korea/sw-anu/2023로 명명하였고, 전장유전체 분석과 분자적 특성을 분석하였다. 계통발생학적 분석 결과 A/wild bird/South Korea/sw-anu/2023는 유라시아 혈통에 속하는 H7N1 인플루엔자 바이러스로 확인되었다. A/wild bird/South Korea/sw-anu/2023 바이러스의 polymerase basic 1(PB)2, PB1, polymerase acidic (PA), nucleoprotein (NP) 유전자는 야생 조류에서 분리되었던 조류 인플루엔자 바이러스유전자와 밀접한 관련이 있는 것으로 밝혀졌으며, hemagglutinin (HA), neuraminidase (NA), matrix (M), nonstructural (NS) 유전자는 집오리에서 분리되었던 조류 인플루엔자 바이러스와 유사하였다. 이러한 결과는 동아시아-호주 이동 경로를 따라 이동하는 야생 조류들 사이에서 새롭게 유전자가 재배열된 재조합 H7N1 조류 인플루엔자 바이러스가 순환되고 있음을 시사하고 있다. 따라서, H7Nx 인플루엔자 바이러스는 전 세계적으로 순환하며, 돌연변이된 H7N1 조류 인플루엔자 바이러스는 인간을 감염시킬 수 있으므로 야생 조류 및 가금류에서 H7N1 조류 인플루엔자 바이러스의 지속적인 감시가 필요할 것이다.

• BMB Reports
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• 제35권5호
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• pp.459-464
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• 2002

Fusogenic liposomes that incorporate Sendai virus envelope proteins, so-called Sendai virosomes, have been developed for in vitro and in vivo genetic modification of animal cells. In this study, several different virosomes of varying lipid compositions were formulated and their in vitro gene-transfer efficiencies compared. The virosomes were prepared by quantitative reconstitution of the Sendai envelope, fusion (F) and hemagglutinin-neuraminidase (HN) proteins into liposomal vesicles. Virosomes that contained luciferase reporter genes were tested in 293 transformed human kidney cells. F/HN-virosomes that were prepared with an artificial Sendai viral envelope (ASVE-virosomes) or phosphatidylserine (PS-virosomes) exhibited an 8- or 6-fold higher gene-transfer efficiency than cationic liposomes that were made with 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP). F/HN-virosomes that were prepared with phosphatidic acid (PA-virosomes) instead of PS were less efficient in gene transfer than either ASVE- or PS-virosomes. In addition, the genetransfer capability of ASVE- and PS-virosomes was maximal at a $Ca^{2+}$ concentration of 510 mM. These results suggest that the incorporated lipid components significantly affect the in vitro gene transfer that is mediated by Sendai F/HN-virosomes.

• Clinical and Experimental Pediatrics
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• 제52권8호
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• pp.862-868
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• 2009

Since its identification in April 2009, a swine-origin H1N1 influenza A virus (S-OIV) which is a reassortment of gene segments from both North American triple-reassortant and Eurasian swine influenza has been widely spread among humans in unexpected rapidity. To date, each gene segment of the 2009 influenza A (H1N1) outbreak viruses have shown high (99.9%) neucleotide sequence identity. As of July 6, 94,512 people have been infected in 122 countries, of whom 429 have died with an overall case-fatality rate of <0.5%. Most confirmed cases of S-OIV infection have been characterized by self-limited, uncomplicated febrile respiratory illness and 38% of cases have also included vomiting or diarrhea. Standard plus droplet precautions should be adhered to at all times. Tests on S-OIV have indicated that current new H1N1 viruses are sensitive to neuraminidase inhibitors (oseltamivir). However, current less virulent S-OIV may evolve into a pathogenic strain or acquire antiviral resistance, potentially with more severe clinical consequences. Efforts to control these outbreaks would be based on our understanding of novel S-OIV and previous influenza pandemics.

• Asian-Australasian Journal of Animal Sciences
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• 제17권6호
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• pp.863-868
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• 2004

Lectin activities and chemical characteristics of Escherichia coli, Lactobacillus spp. and Bifidobacterium spp. originating from the porcine cecal mucosal layer were studied based on hemagglutination assay (HA) and hemagglutination inhibition assay (HIA). Although all the bacterial strains were able to agglutinate erythrocytes of porcine or rabbit origin, much higher HA titers were consistently observed for Lactobacillus spp. than for E. coli or for Bifidobacterium spp. A remarkable reduction in HA titers occurred by the treatment of E. coli and Lactobacillus spp. with protease or trypsin and of Bifidobacterium spp. with protease, trypsin or periodate. There were no significant effects on the HA titers of the three groups of bacteria after the treatment with lipase. Hemagglutination of E. coli was strongly inhibited by D (+)-mannose and D (+)-galactose; Lactobacillus spp. by $\alpha$-L-rhamnose and methyl-$\beta$-galactopyranoside; Bifidobacterium spp. by D (+)-alactose, $\alpha$-L-rhamnose, $\alpha$-L-fucose, L (+)-arabinose, D (+)-mannose, D (-)-fructose at a relatively low concentration (1.43 to 3.75 mg/ml). These results, combined with the enhanced HA activities of the three bacterial strains by modification of rabbit erythrocytes with neuraminidase and abolished HA activity of E. coli after treatment with $\beta$-galactosidase, indicate that it might be the glycoproteinous substances surrounding the surface of the bacterial cells that are responsible for the adhesions of these microorganisms by recognizing the specific receptors on the red blood cell.

• Journal of Microbiology and Biotechnology
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• 제21권5호
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• pp.449-454
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• 2011

The infection of pandemic influenza viruses such as swine flu (H1N1) and avian flu viruses to the host cells is related to the following two factors: First, the surface protein such as HA (hemagglutinin) and NA (neuraminidase) of the influenza virus. Second, the specific structure of the oligosaccharide [sialic acid(${\alpha}2$-6) galactose(${\beta}1$-4)glucose or sialic acid(${\alpha}2$-3)galactose(${\beta}1$-4)glucose] on the host cell. After recognizing the specific structure of the oligosaccharide on the surface of host cells by the surface protein of the influenza virus, the influenza virus can secrete sialidase and cleave the sialic acid attached on the final position of the specific structure of the oligosaccharide on the surface of host cells. Tamiflu (oseltamivir), known as a remedy of swine flu, has a saccharide analog structure, especially the sialic acid analog. Tamiflu can inhibit the invasion of influenza viruses (swine flu and avian flu viruses) into the host cells by competition with sialic acid on the terminal position of the specific oligosaccharide on the surface of the host cell. Because of the emergence of Tamiflu resistance, the development of new potent anti-influenza inhibitors is needed. The inhibitors with positive-charge groups have potential as antiviral therapeutics, and the strain specificity must also be resolved.

• BMB Reports
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• 제28권1호
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• pp.6-11
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• 1995

A new lectin, named TRA, was purified from Trichosanthes kirilowii root by acid-treated Sepharose 6B, Mono-Q, and TSK-gel 3000SW column sequential chromatography. The lectin appeared homogeneous by native gel electrophoresis at pH 4.3 and gave two protein bands of Mr=31 and 28 kDa by SDS-PAGE. The N-terminal amino acid sequences of the polypeptides of TRA have not been reported in amino acid sequences of the lectins. TRA lectin formed a precipitate with asialofetuin, neuraminidase-treated fetuin. A sugar inhibition assay indicated that N-acetyl-D-galactosamine, among the monosaccharides tested, was the most potent inhibitor of TRA-induced hemagglutination. Asialofetuin showed a 260-times stronger inhibitory activity than N-acetyl-D-galactosamine. TRA lectin also showed agglutination with normal leukocytes and lymphoma cells, but not with premature hemopoietic cells. These results suggest that TRA is a novel plant lectin.

• 생약학회지
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• 제42권1호
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• pp.9-14
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• 2011

The fruit body of Forsythiae Fructus (Oleaceae), a common Korean medical herb, is widely used in the treatment of cold and inflammation. In order to elucidate the action mechanism and the active principles from the plant against anti-influenza virus, the influenza virus hemagglutinin (HA) and neuraminidase (NA) gene RT-PCR and Viral Screening & Identification (VSI) assay were conducted, and the activity against viral replication was also investigated. Consequently, one active constituent, namely pinoresinol showed the in vitro antiviral principle using a cytopathic effect (CPE) reduction method, indicating pinoresinol possessed anti-influenza viral activity. Furthermore, combination of pinoresinol and Tamiflu exhibited higher activities than Tamiflu alone against influenza virus (H3N2) infection. The results suggested that combination of pinoresinol with Tamiflu could be a better candidate for an ant-H3N2 viral agent in the treatment of the influenza.