Chlorine dioxide (ClO2) has recently emerged as an ideal disinfectant and has shown a wide range of antimicrobial activities in various pathogenic microorganisms. In this study, the virucidal effect of ClO2 at low concentration (0.02 ppm) and higher concentration (0.06 – 0.09 ppm) against Adenovirus and Herpesvirus was evaluated based on the NF T 72-281 and ASTM 1053-11 standard methods at different exposure times. The virus suspension was dried onto the carrier and then exposed to gaseous ClO2 (gClO2) at 22 ± 2∘C. For Adenovirus, exposure at a low concentration of ClO2 at the middle height resulted in the average log10 reduction of 0.95, 2.65, and 5.30 after 1, 3, and 6 h post-exposure (pe), respectively. Moreover, more than 4-log10 reduction was achieved at 4 and 6 h pe with higher concentrations of ClO2. On the other hand, the antiviral activity of gClO2 at the middle height was also effective against Herpesvirus. In particular, at 1 h pe, a less than 4-log10 reduction was observed at all examined concentrations of ClO2, whereas exposure for 3 and 6 h (with low concentration) or 2 h (with higher concentration) inactivated completely viruses attached to the carrier. These results suggested that ClO2 fumigation is a potential alternative method for disinfecting healthcare facilities, high-containment laboratories, and households with a safe concentration for human health.
Fowl adenovirus serotype-4 (FAdV-4) infection, also known as hydropericardium-hepatitis syndrome (HHS), is one of the most prevalent diseases in the Korean poultry industry. Therefore, an effective vaccination against FAdV-4 should be developed for prevention of HHS infection. However, a standard animal model with significant pathologic characteristics has not been established for evaluation of HHS vaccine efficacy. In this study, we comparatively evaluated FAdV-4 pathogenicity from specific- pathogen-free (SPF) chickens using FAdV-4 strain (ADL091024) isolated in laying chickens in Korea according to chicken age, passage number and virus titers. In brief, FAdV-4 passaged four times in yolk sac of SPF eggs with the highest viral titers could induce the most severe clinical signs in 1-day-old chickens, similar to natural HHS outbreaks. Furthermore, the efficacy of a newly developed attenuated live FAdV-4 vaccine candidate was successfully determined using the established 1-day-old SPF chickens. There was no significant pathogenicity based on the criteria such as mortality, body weight, gross lesions, histological lesions and virus detection rates in the vaccination and non-challenge control groups. However, the challenge group without vaccination showed significant pathogenicity including hepatic necrosis, histological lesion scores in the liver and heart, virus replication and decreased body weight gain. In conclusion, the chicken challenge model established in this report was proposed for consistent and reliable evaluation of FAdV- 4 vaccine efficacy.
Obesity is a worldwide disease and one of the major risk factors. Virus among many factors can lead to obesity. Adenovirus 36 (Ad-36) is the adipogenic virus linked with human obesity. Nevertheless, there is no drug to treat both Ad-36 infection and obesity associated with virus. For the precedent study on anti-cholesterol test, Distylium racemosum (D. racemosum), Quercus salicina (Q. salicina) and Raphiolepis indica (R. indica) were selected. This study was carried out to evaluate the anti-cholesterol effects, anti-lipid effects and inhibition of Ad-36 replication from three extracts. D. racemosum (50 μg/mL) inhibited lipid accumulation on 3T3-L1 adipocyte. D. racemosum inhibited adipocyte differentiation through suppression of regulator peroxisome proliferator-activated receptor- γ (PPARγ) genes and adipocyte-specific genes such as adipocyte protein 2 (aP2). D. racemosum inhibited replication of Ad-36 at 50 μg/mL of concentration. Therefore, the extract of D. racemosum could be a candidate for development of anti-Ad-36 and anti-obesity drugs.
Waterborne infectious disease is induced by several pathogenic microbes such as bacteria, viruses and protozoans, and the cases caused by viral infection is currently increasing. Water treatment process could reduce the number of virus in the water, but there were many difficulties to completely remove the virus particles from water. Therefore, the membrane separation technology which was reported to effectively remove pollutants from raw water has attracted increasing attention and demand. Since its efficiency has been introduced, demands for evaluation method toward the membrane filtration process are increasing. However, progression of the method development is slow due to the difficulties in cultivation of several waterborne viruses from animal models or cell culture system. To overcome the difficulties, we used adenovirus, one of the commonly isolated pathogenic waterborne viruses which can grow in cell culture system in vitro. The adenovirus used in this study was identified as human adenovirus C strain. The adenovirus was spiked in the raw water and passed through the microfiltration membrane produced by Econity, a Korean membrane company, and then the viral removal rate was evaluated by real-time PCR. In the results, the amount of virus in the filtered water was decreased approximately by 5 log scale. Because coagulant treatment has been known to reduce filtering function of the membrane by inducing fouling, we also investigated whether there was any interference of coagulant. In the results, we confirmed that coagulant treatment did not show significant interference on microfiltration membrane. In this study, we found that waterborne virus can be effectively removed by membrane filtration system. In particular, here we also suggest that real-time PCR method can rapidly, sensitively and quantitatively evaluate the removal rate of virus. These results may provide a standard method to qualifying membrane filtration processes.
Internalization and expression of extracellular molecules into cells and tissues is known very important process to biological processes and therapy of various diseases. In this study, we analyzed expression pattern of extracellular molecule after transduction into various human cells. To investigate cellular expression of internalized molecule, we used adenovirus containing green fluorescence protein. After infection of adenovirus into various human cells, the efficiency of intracellular gene expression was assessed with determining GFP expressing cells by fluorescence microscopy or FACS. After one day of adenovirus infection into HepG2 and A549, we observed that GFP expression was low at 10moi but expression levels were increased at 100moi in both cells. But, adenovirus infection into HCT116 showed low expression of GFP at concentrations from 1moi to 100moi. After 2 day infection with adenovirus, GFP expression level at 10moi and 100moi was highly increased in HepG2 and A549 compared with 1 day infection. Especially, GFP expression was significantly increased in HCT116 after 2 days infection. However, GFP expressing SKOV3 cells by adenovirus infection were not found in all the experimental conditions tested. For quantitative analysis of GFP expression of cells by adenovirus infection, we carried out FACS analysis. As a result, GFP was expressed at very low levels at 1moi in all cells used in this experiment. GFP expression slightly increased after increasing moi to 10 in HepG2, HCT116, and A549 cells. By 100moi infection of adenovirus, GFP expression was elevated to 10 fold higher than 10moi in HepG2 and A549 and about 4 fold elevation was observed in HCT116. A549 showed 20 fold higher expression of GFP than SKOV3. We also found that GFP expression by adenovirus infection was the highest in HepG2 cells. Protein expression was enhanced by increasing concentrations or time of adenovirus infection. In these results, GFP expression efficiency of adenoviral gene transduction reveals the highest in HepG2 and lowest in SKOV3 among the cells tested. Taken together, we could confirm that intracellular protein expression efficiency by transduction of extracellular gene was different in various human cells. Our study suggests that the cell types and cellular properties should be carefully examined to enhance expression efficiency of extracelluar molecules in biological research and disease therapy
Many methods have been developed for more efficient gene delivery and expression in human cells. A number of studies have been performed in achieving successful gene delivery and expression conditions. We investigated differential gene expression patterns after delivery adenoviral vector containing green fluorescent protein(GFP) gene into human cancer cell lines. We constructed recombinant adenoviral Ad-CMV-GFP containing CMV promoter and GFP gene. The efficiency of gene expression was assessed by observation GFP expressing cells using fluorescent microscopy after transfer of Ad-CMV-GFP in concentrations of 0.1μl. 1μl. 10μl. At first, we evaluated expression patterns of gene in several human cancer cell lines, gastric adenocarcinoma cell line AGS was showed high level of GFP expression compared with colorectal adenocarcinoma cell line HT-29. After transfer 0.1μl of Ad-CMV-GFP in AGS, we could found that GFP expression cells were observed in next day and highly increased 2 days. While, small number of GFP expressing cells were examined in HT-29 and SNU-C4. Therefore, these data showed that AGS was expressed the highest level of GFP and almost AGS cells seems to express GFP in concentration of 1μl of Ad-CMV-GFP. GFP expression pattern in HT-29 reveal that expression was low in next day after gene transfer but significantly increase expression level in 2 days. In case of SNU-C4, GFP expression increased with increasing concentration of Ad-CMV-GFP and t ransfer times. For examine effects of transfer times in small amount gene, we transfer in concentration of 0.1μl Ad-CMV-GFP and detected GFP expression patterns after 2 days or 4 days. As a result, expression level of GFP in AGS was increase about 2 fold after 4 days compared with 2 days, but any difference of GFP expression levels were not showed in HT-29 and SNU-C4. Our study suggested that adenovirus was very efficient gene transfer vector for gene expression in human cancer cell lines. In addition to, we also demonstrated that gene expression patterns was dependent on each human cell lines. Therefore, further studies will be needed to confirm the optimum conditions for efficient gene delivery and expression in each target cell lines with consideration to cellular properties.