• Journal of Microbiology and Biotechnology
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• 제13권4호
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• pp.537-543
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• 2003

The mouse interferon gene (MuIFN-${\gamma}$) was cloned and then used to transform Saccharomyces cerevisiae. Expressed MuIFN-$\{gamma}$ protein (MuIFN-${\gamma}$) was successfully secreted into culture medium due to the presence oi the signal peptide of rice amylase 1A. Two different promoters fused to MuIFN-${\gamma}$ were tested: glyceraldehyde-3-phosphate dehydrogenase (GPD) promoter and a yeast hybrid ADH2-GPD (AG) promoter consisting of alcohol dehydrogenase II (ADH2) and GPD promoter. Using the hybrid promoter, the accumulation of MuIFN-${\gamma}$transcript was the highest after the 24 h cultivation, and then gradually decreased as the cultivation proceeded. However, both cell growth and recombinant MuIFN-${\gamma}$production reached their peaks after the 4-day cultivation. It was possible to produce 6.5 mg/l of MuIFN-${\gamma}$ without any changes in cell growth. Using GPD promoter, the MuIFN-${\gamma}$ transcript accumulation and the recombinant MuIFN-${\gamma}$ production followed the same pattern as the cell growth. However. compared to that of the hybrid promoter, the production of recombinant MuIFN-${\gamma}$ was 0.2 mg/l. The secreted MuIFN-${\gamma}$ had estimated molecular masses of 21 kDa and 23 kDa, which were larger than that of the encoded size due to glycosylation. The protection assay against the viral infection indicated that the recombinant MuIFN-${\gamma}$ was bioactive.

• Journal of Periodontal and Implant Science
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• 제26권1호
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• pp.216-229
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• 1996

Interferon(IFN) is a sort of glycoproteins that are produced by activated lymphocyte, monocyte and fibroblast. IFN has anti-viral effects, immuno-defensive mechanism and regulating properties to the several kinds of cells that includes affect on the bone formation and resorption. The effect of IFN on the osteoclast & other tissue cells has been studied in a number of researchers with the limited reports on the osteoblast. The purpose of this study was to evaluate the effects of IFN on the osteoblastic function. The MC3T3/El cell(Mouse osteoblast) was incubated in ${\alpha}-minimum$ essential medium containing 10% FBS. To detect the cytotoxic effect of $IFN-{\gamma}$ on osteoblast, the cells were cultured in 96-well plate to which $IFN-{\gamma}$ of various concentrations were added for 2 days. After staining with trypan blue, total cells and living cells were counted under microscope. To determine the activity of alkaline phosphataset(ALP), various concentrations of $IFN-{\gamma}$ were treated to culture medium, and biochemical assay was performed. $IFN-{\gamma}$ and $IFN-{\gamma}$ plus cycloheximide were added to culture medium separately and then ALP activity were determined. To detect the effect of the $IFN-{\gamma}$ on the bone formation of osteoblast, long-term culture was performed, and calcified nodule formation were observed using von Kossa's staining. After the addition of $IFN-{\gamma}$ with various concentrations to the medium, no cytotoxic effect of $IFN-{\gamma}$ was detected at any concentration. The significant increase in ALP activity of osteoblast were found the concentration of $IFN-{\gamma}$ 500-2500U/ml and the culture time of 24-48 hours respectively. The enhancement of ALP activity by $IFN-{\gamma}$ of osteoblast was decreased significantly by the treatment of cycloheximide. After long-term culture of osteoblast, the nodule formation was found to be increased in number and density by the addition of 500 U/ml $IFN-{\gamma}$. These results suggest that $IFN-{\gamma}$ was affected on the bone formation of osteoblast. Forthemore this kind of study or $IFN-{\gamma}$ to osteoblast will be held continuously.

• Tuberculosis and Respiratory Diseases
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• 제67권4호
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• pp.331-337
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• 2009

Background: The whole-blood interferon-gamma release assay (QuantiFERON-TB Gold [QFT-G]: Cellestis, Carnegie, Victoria, Australia) has been studied primarily for the use of diagnosing active pulmonary tuberculosis (TB) or latent TB. In the present study, the usefulness of QFT-G was evaluated for the diagnosis of extra-pulmonary tuberculosis (EP-TB). Methods: From June 2006 to February 2009, we evaluated the usefulness of QFT-G in patients (n=65) suspected with EP-TB, retrospectively. The diagnostic sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the QFT-G assay were analyzed. Results: EP-TB was diagnosed in 33 (51%) participants. The overall sensitivity, specificity, PPV, and NPV of the QFT-G assay for EP-TB were 78%, 79%, 81%, and 77%, respectively. Of the 33 with EP-TB, 14 (42%) were diagnosed with TB pleurisy, 7 (21%) with TB lymphadenitis, 7 (21%) with intestinal TB, and 5 (15%) with EP-TB in other sites. In subgroup analyses according by site of infection, the QFT-G showed 86% sensitivity, 64% specificity, and 78% NPV in TB pleurisy. On the other hand, the sensitivity, specificity, and NPV of the assay were 71%, 83% and 71%, respectively in TB lymphadenitis, and 86%, 100% and 88%, respectively in intestinal TB. Among the patients with suspected alternative site EP-TB, the sensitivity, specificity, and NPV of the assay were 50%, 80% and 67%, respectively. Conclusion: The QFT-G assay showed moderate diagnostic accuracy in EP-TB. However, negative QFT-G assay does not exclude EP-TB because of the low NPV of this assay.

• 한국균학회지
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• 제27권3호통권90호
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• pp.237-241
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• 1999

잔나비걸상 Elfvingia applananta 자실체의 수용성성분 EA의 varicella zoster virus(Oka strain; VZV/oka)에 대한 항바이러스효과를 plaque reduction assay에 따라 실험한 결과 EA는 용량의존적으로 plaque 형성을 억제하였으며 $EC_{50}$는 $464.14\;{\mu}g/ml$이었다. EA와 단백질성 항바이러스제인 interferon(IFN) alpha 및 IFN gamma와의 병용시험 결과, 단독처리시와 병용처리시에 m(slope) value가 서로 유사한 값을 보였으므로 이들은 상호 배타적인 약물(mutually exclusive drug)임을 알 수 있었고, IFN alpha와의 병용시 combination index(CI)는 f(a)가 0.50에서 0.90인 유효농도 범위내에서 $0.83{\sim}1.09$의 값을 나타내어 부분적 상승 또는 상가효과를 보였으며, IFN gamma와의 병용시에는 $1.20{\sim}1.24$를 나타내어 길항효과를 보였으므로, IFN alpha와의 병용이 IFN gamma와의 병용보다 더 우수한 병용효과를 나타내었다.

• Tuberculosis and Respiratory Diseases
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• 제81권1호
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• pp.59-72
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• 2018

Background: It remains uncertain if $interferon-{\gamma}$ release assays (IGRAs) are superior to the tuberculin skin test (TST) for the diagnosis of active tuberculosis (TB) or latent tuberculosis infection (LTBI) in immunosuppressed populations including people with human immunodeficiency virus (HIV) infection. The purpose of this study was to systematically review the performance of IGRAs and the TST in people with HIV with active TB or LTBI in low and high prevalence TB countries. Methods: We searched the MEDLINE database from 1966 through to January 2017 for studies that compared results of the TST with either the commercial QuantiFERON-TB Gold in Tube (QFTGT) assay or previous assay versions, the T-SPOT.TB assay or in-house IGRAs. Data were summarized by TB prevalence. Tests for concordance and differences in proportions were undertaken as appropriate. The variation in study methodology was appraised. Results: Thirty-two studies including 4,856 HIV subjects met the search criteria. Fourteen studies compared the tests in subjects with LTBI in low TB prevalence settings. The QFTGT had a similar rate of reactivity to the TST, although the first-generation version of that assay was reactive more commonly. IGRAs were more frequently positive than the TST in HIV infected subjects with active TB. There was considerable study methodology and population heterogeneity, and generally low concordance between tests. Both the TST and IGRAs were affected by CD4 T-cell immunodeficiency. Conclusion: Our review of comparative data does not provide robust evidence to support the assertion that the IGRAs are superior to the TST when used in HIV infected subjects to diagnose either active TB or LTBI.

• 생약학회지
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• 제30권3호
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• pp.244-249
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• 1999

In order to find less toxic antiviral agents from Basidiomycetes, EA, the water soluble substance, was prepared from the carpophores of Elfvingia applanata(Pers.) Karst. Antiviral activity of EA against vesicular stomatitis virus [Indiana serotype, VSV(IND)] was examined in Vero cells using plaque reduction assay in vitro. And the combined antiviral effects of EA with interferon (IFN) alpha or gamma were examined on the multiplication of VSV(IND). EA caused a concentration-dependent reduction in the plaque formation of VSV(IND) with 50% effective concentration $(EC_{50})$ of $104.02\;{\mu}g/ml$. The results of combination assay were evaluated by the combination index (CI) that was analysed by the multiple drug effect analysis. All cases of the combination of EA with IFN alpha or IFN gamma showed potent synergism with CI values of $0.38{\sim}0.52$ for $50{\sim}90%$ effective levels.

• Tuberculosis and Respiratory Diseases
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• 제45권6호
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• pp.1167-1177
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• 1998

연구배경 : 결핵은 우리나라에서 아직도 흔하게 발생하는 질환으로 세포면역반응에 의해 육아종이 형성되며, 이 과정에서 대식세포가 분비하는 tumor necrosis factor-alpha (TNF-$\alpha$), Th1 세포가 생성하는 gamma-Interferon (INF-$\gamma$), 내피 세포가 표현하는 intercelluar adhesion molecule-1 (ICAM-1)이 중요한 역할을 할 것이라고 생각되었다. 방 법 : 저자들은 결핵의 경중(輕重)과 이러한 물질들이 관련이 있는가를 알아보기 위하여, 환자의 혈액을 채취하여 TNF-$\alpha$, INF-$\gamma$를 radioimmuno assay(RIA)로, ICAM-1이 혈액으로 유리된 형태인 sICAM-1을 enzyme linked immunosolvent assay(ELISA)로 각각 측정하였다. 또한 화학 요법에 따른 변화를 알기 위해 치료 시작후 6개월 시점에서 다시 추적검사를 실시하였다. 결 과 : TNF-$\alpha$, INF-$\gamma$, sICAM-1은 중등증과 중증의 결핵에서는 의미 있게 증가하였고, 경증에서는 의의가 없었다. 6개월간의 항결핵 치료후, sICAM-1은 임상경과에 동반하여 의미있는 감소를 보였지만. TNF-$\alpha$, INF-$\gamma$에서는 감소는 있었지만 의의는 없었다. 결 론 : 본 실험 결과 결핵의 세포 면역 매개과정에는 TNF-$\alpha$와 INF-$\gamma$가 매우 중요한 역할을 하며, 그 반응 정도가 질병의 병기에 따라 심할수록 많이 증가함을 관찰하였다. ICAM-1은 TNF-$\alpha$와 INF-$\gamma$ 농도와 비례하여 sICAM-1이 증가하였고, 질병의 병기에 따라 농도의 차이가 있을뿐 아니라, 치료경과에 비례하여 농도변화를 보여, 질병의 할동성을 나타내는 것 외에 치료 경과를 나타내는 지시자로서의 가능이 있을 것으로 생각된다.

• 대한의생명과학회지
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• 제19권2호
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• pp.90-97
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• 2013

The tuberculin skin test (TST) and interferon gamma (IFN-${\gamma}$) release assay (IGRA) have been widely used for diagnosis of latent tuberculosis infection (LTBI). In order to overcome limitations of current LTBI diagnostic methods, the development of a novel molecular assay which is able to measure the IFN-${\gamma}$ messenger RNA (mRNA) expression level after stimulation with Mycobacterium tuberculosis (MTB) specific antigen was recently developed. The ability of a molecular assay to detect MTB infection was similar to commercial IGRA however, the optimal incubation time for stimulating IFN-${\gamma}$ was not yet established. Therefore, in this study the direct comparisons of MTB Ag stimulation times (4 and 24 hrs) were performed for diagnosis of MTB infection. Data showed that the coincident rate between QFT-GIT IFN-${\gamma}$ ELISA and IFN-${\gamma}$ RT-PCR (4 hrs) was 88.35% and that of QFT-GIT and IFN-${\gamma}$ RT-PCR (24 hrs) was 70.85%. Based on a receiver operating characteristic (ROC) curve, the 4 hrs-MTB specific Ag stimulation time for IFN-${\gamma}$ RT-PCR had the significant P value, 95% CI value, and AUC (P < 0.0001, 95% CI=0.82 to 1.02, and AUC=0.9214) in comparison with 24 hrs-MTB specific Ag stimulation time (P = 0.009, 95% CI=0.06 to 0.94, and AUC=0.7711). These results show that 4-hr was the most optimal MTB Ag stimulation time for performing IFN-${\gamma}$ RT-PCR. Although semi-quantitative RT-PCR had a few analytical limitations, it might be useful as an alternative molecular diagnostic method for detecting MTB infection.

• 대한영상의학회지
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• 제82권6호
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• pp.1524-1533
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• 2021

목적 인터페론-감마 분비 검사(interferon-gamma release assay; 이하 IGRA) 결과가 양성인 의료종사자의 흉부 X선(chest X-ray; 이하 CXR) 및 CT 결과를 기반으로 결핵의 발생률을 조사하고, 결핵 진단에서 진단 영상의 추가적인 역할을 알아보고자 하였다. 대상과 방법 IGRA를 시행 받은 1976명의 의료 종사자 중에서 IGRA 양성자를 후향적으로 조사하였다. 상부 폐야의 군집 결절 또는 선형 음영을 흉부 X선 양성으로 간주하였고, CT 결핵소견은 활성, 활동성미정, 비활동성, 정상으로 분류하였다. 활성 또는 활동성미정을 CT 양성으로 정의하였다. 결과 IGRA 검사 결과 255명(12.9%)에서 양성이었다. CXR과 CT는 각각 249명(99.2%)과 113명(45.0%)에서 시행되었다. CXR 양성 소견은 249명 중 7명(2.8%), CT 양성 소견은 113명 중 9명(8.0%)에서 각각 나왔다. 9명의 CT 양성 대상자 중 활성 또는 활동성미정 결핵 소견은 각각 6명(5.3%)과 3명(2.7%)에서 발견되었다. Acid-fast bacilli 염색, 배양 및 결핵에 대한 polymerase chain reaction을 포함한 미생물적 검사는 9명의 CT 양성 피험자 모두에서 음성이었다. CT 양성 피험자 9명은 경험적 항결핵약물 치료를 받았고, 이 9명 중 3명은 CXR 음성 소견이었다. 결론 IGRA 양성 의료 종사자에서 CT 검사는 무증상 결핵을 진단하는 데 도움을 주었다.

• Tuberculosis and Respiratory Diseases
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• 제83권4호
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• pp.283-288
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• 2020

Background: Latent tuberculosis (TB) infection among TB contacts is diagnosed using plain chest radiography and interferon-gamma release assays (IGRAs). However, plain chest radiographs often miss active TB, and the results of IGRA could fluctuate over time. The purpose of this study was to elucidate changes in the results of the serial IGRAs and in the findings of the serial submillisievert chest computed tomography (CT) scans among the close contacts of active pulmonary TB patients. Methods: Patients age 20 or older with active pulmonary TB and their close contacts were invited to participate in this study. Two types of IGRA (QuantiFERON-TB Gold In-Tube assay [QFT-GIT] and the T-SPOT.TB test [T-SPOT]) and submillisievert chest CT scanning were performed at baseline and at 3 and 12 months after enrollment. Results: In total, 19 close contacts participated in this study. One was diagnosed with active pulmonary TB and was excluded from further analysis. At baseline, four of 18 contacts (22.2%) showed positive results for QFT-GIT and T-SPOT; there were no discordant results. During the follow-up, transient and permanent positive or negative conversions and discordant results between the two types of IGRAs were observed in some patients. Among the 17 contacts who underwent submillisievert chest CT scanning, calcified nodules were identified in seven (41.2%), noncalcified nodules in 14 (82.4%), and bronchiectasis in four (23.5%). Some nodules disappeared over time. Conclusion: The results of the QFT-GIT and T-SPOT assays and the CT images may change during 1 year of observation of close contacts of the active TB patients.