• The Korean Journal of Zoology
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• v.22 no.4
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• pp.141-152
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• 1979

Feline leukemia virus DNA polymerase was purified by ion-exchange and nucleic acid affinity chromatographies. The enzyme consists of a single polypeptide chain of approximately 72, 000 molecular weight as determined by both of a glycerol density gradient centrifugation and SDS-polyacrylamide gel electrophoresis. The preferred divalent cation for DNA synthesis is $Mn^2+$ on a variety of template-primers, and its optimum concentration appears to be significantly lower than reported results of other mammalian type-C viral enzymes. The divalent cation requirement for maximum activity of RNase H is similar to those of DNA polymerase. Both DNA polymerase and RNase H activities appear to reside on the same molecule as demonstrated by the copurification of both activities through various purification steps. An additional RNase H without detectible polymerase activity was generated by a limited chymotrypsin digestion. This RNase H activity was inhibited equally effectively as RNase H in the intact reverse transcriptase by antisera prepared against reverse transcriptase of feline leukemia virus. Neutralization and binding test showed that antibody binding to reverse transcriptase molecule did not completely inhibit the polymerase activity.

• Journal of Veterinary Clinics
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• v.31 no.1
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• pp.1-5
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• 2014

Feline leukemia virus (FeLV) is a retrovirus that represents one of the most common and important infectious diseases of cats worldwide and it is responsible for more deaths among cats than any other infectious diseases. Prevalence data are necessary to define prophylactic, management and therapeutic measures for stray, feral and owned cats which are lacking in Bangladesh. The study was carried out to determine the prevalence of FeLV infection in Mymensingh district of Bangladesh using RapiGEN$^{(R)}$ FeLV Ag Test Kit (RapiGEN$^{(R)}$ Inc., Republic of Korea), a rapid one-step immunochromatographic assay. Blood samples from total 130 cats (23 owned cats and 107 unowned cats) were collected and tested following the manufacturer's instruction. An overall prevalence of FeLV infection was 1.54% (2/130). Prevalence was found 1.79% (2/112) on Day 0-up to one year aged cats (young) but no positive case was found in above 1 year (Adult) aged group. In male and female cats, the prevalence was 1.72% (1/58) and 1.39% (1/72), respectively. In un-owned cats the prevalence was 1.87%. Positive cases to FeLV were found only in clinically sick cats. No significant relationship was found according to age, sex, ownership status and health status. To the best of our knowledge this is the first report of the prevalence of FeLV infection in Bangladesh using RapiGEN$^{(R)}$ FeLV test kits which is very much effective because it is easy to apply, less expensive and quick screening of such type of infection.

• Journal of Veterinary Clinics
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• v.22 no.1
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• pp.1-5
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• 2005

Seroprevalence of feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) infections were surveyed in 875 domestic cats derived from 4 major cities and 4 provinces in Korea. Of those tested, 715 were healthy and 160 were sick. FeLV and FIV were tested with AGEN/sup ⓡ/ FeLV-FIV, a commercial combo test kit. Ten out of 875 cats (1.1 %) were seropositive for FeLV and none out of 875 cats (0%) was positive for FIV, respectively. The positive rates for FeLV were 3.8% in sick cats and 0.6% in healthy cats. The cats at the age of more than 1 year showed higher incidence rates than the younger ones. There were no significant relationships either with the environment or with the sex. The prevalence of seropositive FeLV was 0.7% in mixed cats and 1.6% in pedigree cats. With respect to the regional prevalence of the FeLV, the highest seroprevalence (9.5%) was found in Gyeongsang province.

• Proceedings of the Korea Contents Association Conference
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• 2015.05a
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• pp.227-228
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• 2015

질병 치료에 대한 패러다임이 과거 치료 위주에서 조기진단 및 예방의 개념으로 전환되고 있으며 진단용 마커와 단클론 항체 제작은 핵심 기술로 부각되고 있다. 현재까지의 항원결정부위(epitope) 예측은 단백질의 1차구조인 아미노산 배열 순서를 바탕으로 추출되어 진다. 하지만 항원결정부위는 수용성의 항체와 직접 결합하기 때문에 친수성 잔기가 차지하는 비율이 높아야 하며, 면역계가 쉽게 인지할 수 있도록 노출되어 있어야하고, 긴 선상의 폴리펩티드 단백질이 3차원 구조를 형성하기 위해 회전, 유연성 등이 요구된다. 따라서 한 가지 성질 중심으로 할 경우 오류가 나올 가능성이 있다. 이를 보완하기 위하여 본 연구에서는 친수성(hydrophilicity), 극성(polarity), 파묻힘성(buried residues), 접근성(accessibility), 회전성(${\beta}-turns$), 유연성(flexibility), 굴절성(refractivity) 등을 분석한 후 통합 예측시스템을 개발하였다. 이를 검증하기 위해 고양이 백혈병 바이러스의 항원결정부위를 예측해보았다.