• Journal of Microbiology
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• 제45권1호
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• pp.69-74
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• 2007

Escherichia coli is a clonal species, and occurs as both commensal and pathogenic strains, which are normally classified on the basis of their O, H, and K antigens. The O-antigen (O-specific polysaccharide), which consists of a series of oligosaccharide (O-unit) repeats, contributes major antigenic variability to the cell surface. The O-antigen gene cluster of E. coli O66 was sequenced in this study. The genes putatively responsible for the biosynthesis of dTDP-6-deoxy-L-talose and GDP-mannose, as well as those responsible for the transfer of sugars and for O-unit processing were identified based on their homology. The function of the wzy gene was confirmed by the results of a mutation test. Genes specific for E. coli O66 were identified via PCR screening against representatives of 186 E. coli and Shigella O type strains. The comparison of intergenic sequences located between galF and the O-antigen gene cluster in a range of E. coli and Shigella showed that this region may perform an important function in the homologous recombination of the O-antigen gene clusters.

• Archives of Pharmacal Research
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• 제24권6호
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• pp.557-563
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• 2001

Oral tolerance is thought to play a role in preventing allergic responses and immune-mediated diseases. An improved mouse model of the oral tolerance to Japanese cedar pollen (JCP) as antigen was developed in order to detect induction of the tolerance, and the immunological characteristics of this model were also elucidated. Oral tolerance was induced by C3H/ HeN mice given an oral administration of 10 mg JCP 7 days before immunization with an i.p. injection of 0.1 mg JCP in complete Freunds adjuvant (CFA). The effects of oral JCP on systemic immunity were assessed by enzyme-linked immunosorbent assay (ELISA) of immunoglobulin (Ig) levels in serum collected on day 7 or 14 after immunization. Oral tolerance to JCP was adequately induced on day 7 after immunization and was more effective in C3H/HeN mice than in BALB/c mice. The tolerance was primarily concerned with the decreased serum levels of antigen-specific IgG. In these mice, oral administration of JCP also suppressed various immune responses to the antigen including delayed-type hypersensitivity (DTH), total Igl level and anti-JCP IgGl level. The suppression of these immune responses by the oral antigen was associated with a significant reduction in interleukin-4 (IL-4) production. These findings therefore indicate that this C3H/HeN mice model has potential use in detecting the induction of oral tolerance by JCP and suggest that this tolerance model may be effective in the treatment and prevention of allergic responses caused by the antigen.

• 동의생리병리학회지
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• 제26권4호
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• pp.469-474
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• 2012

Fagopyrum esculentum(FE) is an important food crop and medicinal plant that is used to improve diabetes, obesity, hypertension, hypercholesterolemia and constipation in Korea, but the underlying mechanisms involved in its anti-allergic activity are not fully understood. We investigated the effects on the release of inflammatory mediator and proximal signal events in $Fc{\varepsilon}RI$-mediated RBL-2H3 cell activation. FE reduced antigen (DNP-HSA)-induced release of histamine, prostaglandin D2 (PGD2) and cysteinyl Leukotriene (cysLT) in IgE-sensitized RBL-2H3 cells. In addition, it inhibited antigen-induced HDC2 and COX-2 and 5-LO mRNA expression in IgE-sensitized RBL-2H3 cells. FE also suppressed antigen-induced $Fc{\varepsilon}RI{\beta}$ and $Fc{\varepsilon}RI{\gamma}$ subunit mRNA expression in these cells. To identify the mechanisms underpinning the inhibition of release of inflammatory mediators such as histamine and PGD2 and cysLT by FE, we examined the proximal signal events of intracellular FceRI signaling molecules. FE suppressed antigen-induced phosphorylation of Lyn, Syk, LAT, $PLC{\gamma}1$, PI3K, Akt and cPLA2. Collectively, the anti-allergic effects of FE in vitro suggest its possible therapeutic application to inflammatory allergic diseases, in which its inhibition of inflammatory mediator and FceRI-dependent signaling events in mast cells may be hugely beneficial.

• 한국미생물·생명공학회지
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• 제17권1호
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• pp.81-83
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• 1989

The flagella antigenic variation of nine Bacillus thuringiensis serovar kurstaki temperature-sensitive mutants grown at the permissive temperature (3$0^{\circ}C$) was detected by a serological agglutination between H-antigen and antiserum. The flagella antigens were injected to rabbits to prepared their antisera, and then their homologous and heterologous titers of the antisera were measured. The homologous titers were ranged from 1:6,400 to 1:12,800, but the heterologous titers were very low. The H-antigen of the wild type strain was not agglutinated to 4 heterologous antisera, ts-U23 not to 7, ts-U3l not 5, ts-U32 not to 4, ts-U33 not to 7, ts-U7l not to 4, ts-U73 not to 6, ts-U74 not to 6, ts-U91 not to 4 and ts-U603 not to 4 antisera.

• Journal of Microbiology
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• 제33권4호
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• pp.355-362
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• 1995

Induction of antibody production in C3H/He mice by bacterial infection is regulated through the processing exerted by antigen presenting cells. From the studies with Psudomonas aeruginosa, Salmonella typhimurium, and Micrococcus luteu, lipopolysaccharides (LPS) in Gram negative bacteria, which are known to be T-cell independent B cell mitogen, seem to be the major factor stimulating immune responses via activation of macrophages. Activation of macrophage, however, does not seem to correlate with antibody production. M. luteus was easily eliminatd by activated macrophages, while the processed antigens were immediately releasedd into culture medium before presentation. Nevertheless, antigens from Gram positive bacteria, Staphylococcus aureus and Bacillus subtilis, were very very active in chemotaxis and activation of periotoneal macrophages as well as in antien presnetation, while the very nature of the antigens is not yet clearly understood.

• Pediatric Infection and Vaccine
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• 제14권1호
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• pp.97-103
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• 2007

목 적 : Lewis b($Le^b$) 항원과 BabA 단백은 H. pylori가 위점막에 부착하는 것과 연관이 있는 것으로 알려져 있다. 소아에서 H pylori 감염에 대한 위점막의 면역 반응은 성인에서의 반응과 차이가 있을 것으로 추정되지만 Le 항원의 발현에 관한 연구는 매우 드물다. 이에 저자들은 국내 소아 H. pylori 양성 환자의 위점막에서 Le 항원의 발현 양상을 알아보기 위하여 본 연구를 시행하였다. 방 법 : 2002년 1월부터 2004년 1월까지 상부 위장관 증상 때문에 소아과를 방문하여 내시경 검사를 시행받은 소아 환자를 대상으로 하였다. 위전정부에서 최소한 2개 이상의 조직 검체를 생검하여 CLO 검사와 조직 특수 염색(Warthin-starry) 검사를 각각 시행하여 모두 양성인 경우에 H. pylori에 감염된 것으로 판정하였다. H. pylori 양성 35명과 H. pylori 음성 19명의 위점막 파라핀 조직에서 DNA를 추출하여 cagA, babA2 특이 시발체를 이용하여 PCR을 시행하였다. 위점막 생검 조직을 대상으로 $Le^a$, $Le^b$, $Le^x$와 $Le^y$ 항체를 사용하여 면역조직화학적 염색을 시행한 다음 각각의 Le 항원의 발현 정도를 평가하였다. 결 과 : H. pylori 양성 환자에서 $Le^a$ 항원은 60%(21명/35명), $Le^b$ 항원 97%(34명/35명), $Le^x$ 항원 88%, $Le^y$ 항원은 100%에서 발현이 확인되었다. H. pylori 음성 환아군에서는 $Le^a$, $Le^b$, $Le^x$ 및 $Le^y$ 항원이 각각 52%, 100%, 89%, 100%에서 발현되었다. H. pylori 양성 유무에 따른 $Le^b$ 항원 발현의 차이는 없었다. CagA 및 babA2 유전자는 H. pylori 양성 환자군 중 각각 65.7%(23명/35명), 25.6%(8명/35명)에서 확인되었다. Lewis 항원들의 발현에 따른 H. pylori 감염, cagA 양성 및 babA2 양성율의 차이는 없었다. 결 론 : 국내 소아의 위점막에서 높은 $Le^x$와 $Le^y$ 항원의 발현율을 확인할 수 있었으나 H. pylori 감염 및 babA2의 양성 여부와는 관련이 없었다. Lewis 항원 이외의 다른 점막 수용체들과 세균 독소들에 대한 지속적 연구가 필요할 것으로 생각된다.

• 한국잠사곤충학회지
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• 제15권2호
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• pp.1-7
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• 1973

잠란 난령별 추출액을 항원으로 토끼의 항혈청을 만들고 이들 항원과 항체와의 사이에 생기는 반응에 의하여 항원성을 비교하였다. 그 결과는 아래와 같다. 1) 잠란내 난령별 조성물질은 토끼의 이정맥에 주입하였을 경우에 대부분의 잠란항원 A.B.D.G.H.J는 항체를 형성하였으나 그 일부의 항원 C.E.F.I에서는 항체 형성이 식별되지 않았다. 2) 잠란 잠령별 잠란내 조성물질은 생종인 대조 A구, B구와 대조 B구와 AKT 흑종 48시간구 D, 흑확잠 103과 잠 104에 있어서 G.H와 J는 서로 공통항원을 가지고 있었으나 그 일부 즉 AKT의 E.F 잠 104의 20시간구 I에서는 특이적인 항원항체반응을 인정할 수 없었으며 타 항체, D.E.F와의 사이에서는 비특이적인 항원항체반응을 인정할 수 있었다. 3) 각 난령별 잠란내에는 공통항원성 물질이 존재하는 것으로 사려되며 각 난령에 따른 특수항원성을 보기 위해서 흡습법에 의한 시험을 한 결과 B.D.G.J의 4개의 특이적인 항원을 인정할 수 있었다.

• BMB Reports
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• 제40권6호
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• pp.1002-1008
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• 2007

PreS domain of Hepatitis B virus (HBV) surface antigen is a good candidate for an effective vaccine as it activates both B and T cells besides binding to hepatocytes. This report deals with overexpression and purification of adr subtype of surface antigen that is more prevalent in Pakistan. PreS region, comprising 119 aa preS1 region plus a 55 aa preS2 region plus 11 aa from the N-terminal S region, was inserted in pET21a+ vector, cloned in E. coli $DH5\alpha$ cells and expressed in E. coli BL21 codon+ cells. The conditions for over expression were optimized using different concentrations of IPTG (0.01-5 mM), and incubating the cells at different temperatures (23-$41^{\circ}C$) for different durations (0-6 h). The cells were grown under the given optimized conditions (0.5 mM IPTG concentration at $37^{\circ}C$ for 4 h), lysed by sonication and the protein was purified by ion exchange chromatography. On the average, 24.5 mg of recombinant protein was purified per liter of culture. The purified protein was later lyophilized and stored at $-80^{\circ}C$.

• 생명과학회지
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• 제15권3호
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• pp.492-498
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• 2005

PLDI 활성화 기전은 여러 보고가 있으나 PLD2 활성화에 대한 기전은 아직 연구의 대상이다. RBL-2H3 비만세포에서 HA-PLD2의 인산화 가능한 타이로신 잔기를 점돌연변이 시킨 DNA플라즈미드를 이용하여 11번, 14번, 470번의 타이로신이 항원자극에 의해 인산화 됨을 알아냈고 특히 470번 타이로신의 인산화가 PLD2 활성화에 중요하다는 결과를 얻었다.

• Asian-Australasian Journal of Animal Sciences
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• 제10권1호
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• pp.141-146
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• 1997

Postmortem examination was conducted on 350 (three hundred and fifty) chickens. Related samples (Liver, heart, ovary, spleen, bone-marrow, and caecal junction) were collected. The appropriate materials from the samples were cultured into different media. A total 40(forty) isolates of salmonella pullorum and S. gallinarum were identified and preserved. Characterization of the isolates were done by cultural, morphological, biochemical, and serological tests. Salmonella pullorum antigen was prepared from the local isolate, standardized and tested. This antigen was used in the field for the detection of pullorum or fowl typhoid infection or carrier birds. The antigen consisted of suspension of Salmonella pullorum in 0.50 percent sodium chloride plus 1.5 percent sodium sulfate and inactivated with 1% formalin U.S.P. and standardized with McFarland scale iv or by pour plate method containing 800 million organisms per milliliter and stained by the addition of alcoholic crystal violet. Sterility, safety and potency were tested and found as good as other international antigens. The antigen was found to retain its quality for six months when preserved at room temperatures. The test was made by mixing one drop of the antigen with a drop of blood or a drop of serum, on a glass plate or white tile. The locally produced antigen was as good as antigens from Japan, Hungary, Holland and India. A serological study was conducted with the locally prepared antigen in different farms, and the incidence was 0-4% in government farms, 5-10% in commercial imported breeds and 0-3% in cross breed local farms respectively.