• Parasites, Hosts and Diseases
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• 제49권3호
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• pp.207-212
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• 2011

Rapid serodiagnostic methods for Toxoplasma gondii infection in cats are urgently needed for effective control of transmission routes toward human infections. In this work, 4 recombinant T. gondii antigens (SAG1, SAG2, GRA3, and GRA6) were produced and tested for the development of rapid diagnostic test (RDT). The proteins were expressed in Escherichia coli, affinity-purified, and applied onto the nitrocellulose membrane of the test strip. The recombinant SAG1 (rSAG1) showed the strongest antigenic activity and highest specificity among them. We also performed clinical evaluation of the rSAG1-loaded RDT in 182 cat sera (55 household and 127 stray cats). The kit showed 0.88 of kappa value comparing with a commercialized ELISA kit, which indicated a significant correlation between rSAG1-loaded RDT and the ELISA kit. The overall sensitivity and specificity of the RDT were 100% (23/23) and 99.4% (158/159), respectively. The rSAG1-loaded RDT is rapid, easy to use, and highly accurate. Thus, it would be a suitable diagnostic tool for rapid detection of antibodies in T. gondii-infected cats under field conditions.

• Parasites, Hosts and Diseases
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• 제59권1호
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• pp.9-14
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• 2021

Toxoplasma gondii seroprevalence have been rapidly increasing in some parts of Korea. We analyzed prevalence of anti-Toxoplasma gondii antibodies, using a rapid diagnostic test (RDT), in the sera of 552 residents in Ganghwagun, 661 ones in Cheorwon-gun, and 305 ones in Goseong-gun, Korea in 2019. IgG/IgM RDT mounted with recombinant fragment of major surface antigen (SAG1), glutathione-S-transferase-linker-SAG1A, were applied to the sera. IgG seroprevalence was 28.1% in Ganghwa-gun, 19.5% in Cheorwon-gun and 35.7% in Goseong-gun. Odds ratios comparing Cheorwon vs Ganghwa was 0.63 (P=0.001) and Goesong versus Ganghwa was 1.47 (P=0.01) adjusting age and sex. Goseong had highest seroprevalence among the 3 counties both in crude rates and logistic regression. Although Cheorwon and Goseong are adjacent to the demilitarized zone (DMZ) in Korea, seroprevalence rate was much higher in Goseong. Further investigation on other DMZ-closed areas is necessary whether they have high prevalence rates compared to the other areas. T. gondii prevalence in Korea is still persists; proper health policy should be established.

• Journal of Veterinary Science
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• 제23권4호
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• pp.52.1-52.7
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• 2022

This paper reports a presumptive severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in a cat. A cat with respiratory disease living with three individuals with coronavirus disease 2019 showed bilateral ground-glass opacities in the lung on X-ray and computed tomography. The clinical swabs were negative for SARS-CoV-2 RNA, but the serum was positive for SARS-CoV-2 antibodies. Interstitial pneumonia and prominent type 2 pneumocyte hyperplasia were noted on histopathology. Respiratory tissues were negative for SARS-CoV-2 RNA or antigen, but the cat was positive for feline parvovirus DNA. In conclusion, the respiratory disease and associated pathology in this cat could have been due to exposure to SARS-CoV-2.

• Asian Pacific Journal of Cancer Prevention
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• 제16권2호
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• pp.719-722
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• 2015

Objective: To evaluate the values of 4 tumor markers in serum and ascites and their ascites/serum ratios in the identification and diagnosis of benign and malignant ascites. Materials and Methods: A total of 76 patients were selected as subjects and divided into malignant ascites group (45 cases) and benign ascites group (31 cases). Samples of ascites and serum of all hospitalized patients were collected before treatment. The levels of carcinoembryonic antigen (CEA), alpha fetoprotein (AFP), cancer antigen 125 (CA125) and carbohydrate antigen 19-9 (CA19-9) were detected by chemiluminescence (CLIA). Results: CEA, AFP and CA19-9 in both serum and ascites as well as CA125 in ascites were evidently higher in the malignant ascites group than in the benign ascites group (P<0.01). Malignant ascites was associated with elevated ascites/serum ratios for AFP and CA125 (P<0.01). The areas under receiver operating characteristic (AUROCs) of CEA and CA125 in ascites and the ratios of ascites/serum of AFP, CEA, CA125 and CA19-9 were all >0.7, suggesting certain values, while those of ascites CA19-9 and serum CEA were 0.697 and 0.629 respectively, indicating low accuracy in the identification and diagnosis of benign and malignant ascites. However, the AUROCs of the remaining indexes were <0.5, with no value for identification and diagnosis. Compared with single index, the sensitivity of combined detection increased significantly (P<0.05), in which the combined detection of CEA, CA19-9 and CA125 in ascites as well as the ratio of ascites/serum of CEA, CA19-9, CA125 and AFP had the highest sensitivity (98.4%) but with relevantly low specificity. Both sensitivity and specificity of combined detection should be comprehensively considered so as to choose the most appropriate index. Conclusions: Compared with single index, combined detection of tumor markers in serum and ascites can significantly improve the diagnostic sensitivity and specificity.

• Clinical and Experimental Pediatrics
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• 제52권5호
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• pp.567-575
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• 2009

목적 : 간질은 전세계인구의 0.5%에서 발병하며 유전적 성향이 많고, 이는 중추신경계의 과 흥분성에 기인한다고 알려져 있다. 최근 프로테오믹스기법의 발달로 질병관련 단백질 동정이 활발히 연구되어지고 있다. 더불어, 간질의 진단은 영상기법 및 뇌파 분석 등이 이용되고 있으나, 가장 손쉽고 경제적인 혈청단백질을 이용한 진단법은 확립되어 있지 못하다. 그러므로 본 연구에서는 측두엽 간질환자의 혈장 단백질을 분석하여 간질의 진단 표지단백질 및 질병관련단백질을 발굴하고자 하였다. 방 법 : 저자들은 8명의 측두엽 간질환자와 8명의 정상인 혈청을 비교하였다. 결 과 : 간질환자의 혈청에서 정상 혈청단백질과 유의하고 일관성 있는 차이를 보이는 12개의 단백질을 발견하였다. 그 중, 6개의 단백질을 동정하였고, 6개의 단백질은 동정하지 못하였다. 더불어, haptoglobin Hp2, PRO2675, immunoglobulin heavy chain constant region gamma 2와 1개의 명명되지 않은 단백질 및 3개의 미지의 단백질을 포함한 7개의 단백질은 간질환자의 혈액에서 증가하였다. 반면, MHC class I antigen, plasma retinol-binding protein precursor 및 3개의 미지의 단백질을 포함한 5개의 단백질은 감소하였다. 결 론 : MHC class I antigen, immunoglobulin heavy chain constant region gamma 2 및 수술 전에 증가하였던 3개의 미지의 단백질 중에서 1개, 감소하였던 3개의 미지의 단백질 중에서 2개를 포함한 모두 5개의 단백질은 간질을 일으키는 뇌 부위 절제 후 정상으로 회복되었다. 이는 이런 단백질들을 측두엽 간질의 진단 및 경과관찰인자로서, 활용할 수 있음을 시사한다. 나아가, 이러한 단백질들은 간질의 병태 생리 연구 및 새로운 치료약물개발의 표적 단백질로 활용될 수 있을 것이다.

• 한국동물위생학회지
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• 제17권2호
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• pp.95-113
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• 1994

To establish an effective diagnostic measure for detection of the antibodies against Actinobacillus pleuropneumoniae, the methods for tube agglutination test (TAT), plate agglutination test (PAT), micro-agglutination test(MAT) and agar-gel immunodiffusion test(ID) were improved and standarized, and the comparative studies were carried out. The results obtained through the experiments were summarized as follows. 1. The rabbit hyperimmune sera to reference serotypes 1 to 6 were cross-tested with TAT, PAT, MAT and ID. In the homologous systems, the range of antibody titers in TAT was 80 to 640, showing the cross-reaction in serotypes 3, 4, 5 and 6. The range of antibody titers in PAT was 4 to 64, showing the cross-reaction in serotypes 3, 4, 5 and 6. In ID, the range of antigen titers was 8 to 32, and cross-reaction was observed in serotype 5. 2. The optimal concentration of antigen in PAT and MAT were 100mg /ml and 1.25mg /ml respectively. The most sensitive reaction in MAT was observed in 52$^{\circ}C$ for 18hrs. 3. In ID, the most promising antigen and the buffer for agar-gel were EDTA-treated antigen and 0.05M tris buffer (pH 7.2), respectively. 4. By the tests for 200 swine sera, it was found that the frequency of positive reaction were 203 in TAT, 240 in PAT and 163 in ID. 5. When compared the titers of TAT with those of MAT for 200 swine sera, MAT showed the higher titer than TAT being increased by relative correlation. Int was found that the titer for positive readings were 20 in TAT and 40 in MAT. 6. when compared the results of ID with those of TAT for 200 swine sera, all sera with TAT titer under 10 were negative in ID. Of the sera with TAT titer 20 and 40, 55.1% nd 91.8% were positive in ID, respectively. All sera with TAT titer above 80 were positive in ID. In comparison of ID and MAT, all sera with MAT titer under 20 were negative in ID. Of the sera with MAT titer 40 and 80, 24.7% and 93.9% were positive in ID, respectively. All sera with MAT titer over 160 showed positive in ID. 7. In conclusion, the established MAT showed high sensitivity but low specificity, wherease ID revealed low sensitivity but high specificity.

• 미생물학회지
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• 제51권2호
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• pp.115-125
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• 2015

단일클론항체 AP64 IgM은 인간의 급성 비임파성 골수암(ANLL) 세포주 HL60에 결합하며 쥐의 ANLL 세포에도 교차결합(cross-react)한다. 또한 complement에 의해 매개되어지면 골수암 억제효과를 나타낸다. 본 연구에서는 RT-PCR에 의해 AP64 IgM을 분비하는 하이브리도마의 $V_H$ 및 $V_L$ cDNA로부터 유래된 재조합 single-chain variable domain fragment (ScFv)를 제조하였다. $V_H$ 및 $V_L$은 15개 아미노산으로 구성된 linker $(G_4S)_3$으로 연결되었다. 재조합 ScFv는 Escherichia coli BMH 71-18에서 single polypeptide chain으로 발현되었다. Periplasmic extract를 $Ni^+$-NTA-agarose affinity column에 가하여 발현된 재조합 ScFv를 정제하였으며 westernblot으로 정제된 단백질을 탐지하였다. 정제된 재조합 ScFv는 AP64 IgM 모항체가 탐지하는 항원과 같은 HL60 세포의 표면항원(약 30 kDa)을 인지하였다. 그러나 HL60의 표면항원에 대한 ScFv의 결합력은 AP64 IgM 모항체보다 낮아서 추후 이에 대한 개선이 필요하다. 종합하여 볼 때 HL60 세포주에 특이적인 재조합 ScFv는 진단 또는 치료목적으로 유용한 생물학적 제재가 될 수 있을 것이다.

• Journal of Veterinary Science
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• 제23권4호
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• pp.55.1-55.12
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• 2022

Background: ASF was first reported in Kenya in 1910 in 1921. In China, ASF spread to 31 provinces including Henan and Jiangsu within six months after it was first reported on August 3, 2018. The epidemic almost affected the whole China, causing direct economic losses of tens of billions of yuan. Cause great loss to our pig industry. As ELISA is cheap and easy to operate, OIE regards it as the preferred serological method for ASF detection. P54 protein has good antigenicity and is an ideal antigen for detection. Objective: To identify a conservative site in the African swine fever virus (ASFV) p54 protein and perform a Cloth-enzyme-linked immunosorbent assay (ELISA) for detecting the ASFV antibody in order to reduce risks posed by using the live virus in diagnostic assays. Method: We used bioinformatics methods to predict the antigen epitope of the ASFV p54 protein in combination with the antigenic index and artificially synthesized the predicted antigen epitope peptides. Using ASFV-positive serum and specific monoclonal antibodies (mAbs), we performed indirect ELISA and blocking ELISA to verify the immunological properties of the predicted epitope polypeptide. Results: The results of our prediction revealed that the possible antigen epitope regions were A23-29, A36-45, A72-94, A114-120, A124-130, and A137-150. The indirect ELISA showed that the peptides A23-29, A36-45, A72-94, A114-120, and A137-150 have good antigenicity. Moreover, the A36-45 polypeptide can react specifically with the mAb secreted by hybridoma cells, and its binding site contains a minimum number of essential amino acids in the sequence 37DIQFINPY44. Conclusions: Our study confirmed a conservative antigenic site in the ASFV p54 protein and its amino acid sequence. A competitive ELISA method for detecting ASFV antibodies was established based on recombinant p54 and matching mAb. Moreover, testing the protein sequence alignment verified that the method can theoretically detect antibodies produced by pigs affected by nearly all ASFVs worldwide.

• Journal of Microbiology and Biotechnology
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• 제17권6호
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• pp.879-890
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• 2007

The identification of tumor antigens is essential for the development of anticancer therapeutic vaccines and clinical diagnosis of cancer. SEREX (serological analysis of recombinant cDNA expression libraries) has been used to identify such tumor antigens by screening sera of patients with cDNA expression libraries. SEREX-defined antigens provide markers for the diagnosis of cancers. Potential diagnostic values of these SEREX-defined antigens have been evaluated. SEREX is also a powerful method for the development of anticancer therapeutics. The development of anticancer vaccines requires that tumor antigens can elicit antigen-specific antibodies or T lymphocytes. More than 2,000 antigens have been discovered by SEFEX. Peptides derived from some of these antigens have been evaluated in clinical trials. This review provides information on the application of SEREX for identification of tumor-associated antigens (TAA) for the development of cancer diagnostics and anticancer therapeutics.

• 한국동물위생학회지
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• 제30권2호
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• pp.205-209
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• 2007

A protein chip based on surface plasmon resonance (SPR) imaging was developed for measuring classical swine fever virus (CSFV) antibody using a recombinant gp55 protein as an antigen. The diagnostic potential of SPR imaging for detecting antibodies to the CSFV gp55 protein was compared with that of a enzyme -linked immunosorbent assay (ELISA) using 70 pig sera. There was a strong positive correlation between the SPR imaging and ELISA (n=70, r=0.916, p<0.01). Therefore, the SPR imaging, which is a label-free and high-through put method, is expected to be a valuable tool in the serodiagnosis of CSFV.