IL-10 and TNF-alpha promoter polymorphisms in susceptibility to systemic lupus erythematosus in Taiwan

OBJECTIVES

The genetic control of Interleukin-10 (IL-10) and Tumour necrosis factor-alpha (TNF-alpha) production and the possible interaction between the two cytokines in influencing SLE susceptibility as well as clinical features has not been completely evaluated in the Taiwanese population.

METHODS

We investigated the association of IL-10 and TNF-alpha promoter polymorphisms (-1082, -819 and -592 for IL-10 gene; -308 for TNF-alpha gene) with SLE in a total of 172 Taiwanese patients and 215 controls.

RESULTS

Our results indicate that IL-10 A/T/A-A/T/A genotype was associated with Taiwanese SLE, whereas no significance was observed between TNF-alpha genotype and SLE. Furthermore, the TNF-alpha G allele frequency of the polymorphism at -308 was significantly decreased in patients with oral ulcers. The combined frequencies of IL-10 A/T/A haplotype and TNF-alpha G-G genotype were significantly increased in SLE patients. In addition, the combined frequencies of IL-10 A/T/A haplotype and TNF-alpha G-G genotype were significantly decreased in patients with oral ulcers.

CONCLUSIONS

These results suggest a significant correlation of the combined IL-10 and TNF-alpha genetic polymorphisms contribute to SLE susceptibility and clinical features in the Taiwanese population.

Abstract 5051: Overexpression of talin 1 (TLN1) in invasive oral squamous cell carcinoma (OSCC)

Oral squamous cell carcinoma (OSCC) is a highly invasive disease displaying frequent tumor recurrence and lymph node metastasis. Genes involved in cytoskeleton remodeling, cell attachment, and cell mobility are suspicious candidates that promote invasiveness. A genomewide study based on Sty1 250K SNP array platform revealed the involvement of TLN1 gene in the 9p13.3 amplicon. Although large scale screening on 123 tumor tissues by dual color-fluorescence in situ hybridization (FISH) indicated low frequency (around 7.3%) of TLN1 amplification in OSCC, the overall gene expression levels were significantly higher in tumor tissues as compared to the adjacent normal oral epithelium (P < 0.01). As compared to other cytoskeleton crossing linkers that can trigger integrin activation, TLN1 stood out to be the most highly expressed one in OSCC. A mouse study revealed that TLN1 overexpression could be detected in invasive tumors but not in the lesions at early stages. Immunohistochemistry (IHC) data revealed stronger TLN1 immunereactivity in OSCC than in normal tissues. More intense staining pattern was detected at the leading edge of cancer cells under going angiogenesis or lymphogenesis. Patients with TLN1 overexpression had a significantly shorter overall survival and higher recurrence rate than those without. Collectively, our study suggested an important role of TLN1 in oral cancer progression.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5051.

Abstract 3091: Oncogenic roles of nuclear VCP in oral cancer development

VCP is a member of AAA-ATPase family that includes putative ATP-binding proteins involved in nuclear envelope reconstruction, cell cycle regulation, Golgi reassembly, suppression of apoptosis, and DNA-damage response. Due to the novel functions, VCP overexpression was linked to cancer development and suggested as a prognostic tumor marker for poor clinical outcome. Our preliminary data of SNP array analysis on 33 fresh clinical OSCC samples identified an amplified region at chromosome 9p13.3 containing the VCP gene. This finding was further validated by FISH analysis on a larger scale using paraffin-embedded oral cancer tissues. Consistent with genomic copy alterations, the mRNA and protein expression levels of VCP were also found higher in OSCC tissues. Interestingly, the nuclear VCP staining correlates with VCP gene amplification and shorter overall survival, suggesting the novel functions of VCP in nucleus during OSCC development. In this study, we identified several nuclear binding partners for VCP in OSCC cells, and signaling networks controlled by VCP during OSCC development were discussed.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 3091.

A novel genetic variant of BMP2K contributes to high myopia

Loss of eye growth regulation may cause myopia, because modulation of optic globe size is essential for the generation of normal optic power. Evidence has implied variations of BMP2 gene expression mediate ocular development and retinal tissue remodeling. Given BMP2 as a potential regulator involved in myopia development, we investigate whether gene BMP2-inducible kinase (BMP2K, BIKe), whose expression is up-regulated during BMP2-induced osteoblast differentiation, contributes to susceptibility of high myopia. Participants grouped into high myopia had a spherical equivalent greater than -6.00 D, compared with a control group of spherical equivalent less than -0.5 D. Genotyping of polymorphisms 1379 G/A (rs2288255) and 3171 C/G (rs12507099), corresponding with 405 Gly/Ser and 1002 Thr/Ser variation in the BMP2K gene were determined by PCR-restriction fragment length polymorphism and associative study performed by comparing high myopic subjects and healthy controls. The frequency of A allele in the BMP2K gene 1379 G/A polymorphism showed a significant difference between cases and controls (P<0.001, OR=2.99, 95% CI=1.62-5.54) and subjects with either AA or AG genotype show higher risk than GG genotype (P<0.001, OR=3.07, 95% CI=1.59-5.92), while 3171 C/G polymorphism was not significant from this survey. These data suggest that BMP2K gene 1379 G/A variant is strongly correlated with high myopia and may contribute to a genetic risk factor for high degrees of myopic pathogenesis.

Serum leptin and adiponectin levels correlate with severity of allergic rhinitis

The aim of this study was to evaluate the roles of leptin and adiponectin, which are adipokines produced by adipose tissue, in childhood allergic rhinitis (AR), and their association with severity of AR, parameters of atopy and pro-/anti-inflammatory cytokines. Serum levels of leptin, adiponectin, mite allergen-specific and total immunoglobulin E, eosinophil cationic protein (ECP), and pro- and anti-inflammatory cytokines were analysed in 97 non-asthmatic children presenting with persistent AR and in 64 controls. The nasal symptom scores and body mass index were evaluated at the time of blood collection. We found that patients had significantly higher serum levels of leptin and significantly lower serum levels of adiponectin than controls. Furthermore, multivariate logistic regression analysis revealed that leptin and adiponectin were significant predictive factors for AR. Serum levels of leptin and adiponectin were significantly correlated with nasal symptom scores. There was no correlation between levels of pro- and anti-inflammatory cytokines and level of leptin or adiponectin. A significant negative correlation was observed between serum levels of adiponectin and ECP levels in AR children. Our findings suggest that serum leptin and adiponectin levels may serve as predictors of disease severity in childhood AR and both of them appear to be attractive candidates for unmasking or modulating AR.

Human lymphocyte antigen B-associated transcript 2, 3, and 5 polymorphisms and haplotypes are associated with susceptibility of Kawasaki disease and coronary artery aneurysm

CAPSULE

HLA-B associated transcript (BAT) 2, 3, and 5 polymorphisms and haplotypes are associated with Kawasaki disease (KD) and coronary artery aneurysm (CAA) formations.

OBJECTIVE

KD, an acute vasculitis with unknown etiology, involves a complex interaction of immuno-inflammatory process, cytokines activation, and genetic factors. We aimed to investigate if genetic variants of human lymphocyte antigen (HLA)-BAT2, 3, and 5 (BAT2, 3, and 5) could be used as markers of susceptibility in KD and CAA.

METHODS

Individuals were divided into three groups: (1) normal controls; (2) KD with CAA; and (3) KD without CAA. Polymorphisms for BAT2 (-8671, 16483), BAT3 (8854, 2-24), and BAT5 (22655, 9569) were genotyped by PCR system with TaqMan allelic discrimination assay. Genotype/allelic frequencies and haplotypes (BAT2(-8671)-BAT2(16483)-BAT3(8854)-BAT3(2-24)-BAT5(22655)-BAT5(9569)) in each group were compared.

RESULTS

Genotype distribution and allele frequency of BAT2 -8671, BAT3 8854, and BAT5 22655, 9569 polymorphisms in each group were significantly different. BAT2 -8671*G, BAT3 8854*C, BAT5 22655*C, and 9569*A-related genotypes and alleles are correlated with the developments of KD and CAA. BAT haplotypes of ATTGTG and ATCATG are associated with higher susceptibilities of KD with CAA susceptibility.

CONCLUSION

BAT2 -8671, BAT3 8854, and BAT5 22655, 9569 polymorphisms as well as BAT haplotypes (ATTGTG and ATCATG) might be associated with higher KD susceptibility and CAA formation. HLA-B region polymorphisms might contribute to the pathogenesis of KD and CAA.

Serum Levels of Resistin in Allergic Rhinitis and its Relationship with Disease Severity

Background

Resistin, a recently discovered adipokine, has been shown to have proinflammatory properties in humans. The purpose of this study was to evaluate serum resistin levels in children with allergic rhinitis (AR) and to investigate its association with clinical disease severity, parameters of atopy and pro-/anti-inflammatory cytokines.

Methods

A case-controlled study was performed on 50 pediatric patients with persistent AR and 30 healthy controls with similar age, sex, and body mass index. Serum levels of resistin, parameters of atopy, and cytokines were analyzed. The nasal symptom scores were evaluated and patients were classified into mild (n = 20) and moderate-severe (n = 30) persistent AR.

Results

Serum levels of resistin were significantly increased in children with AR compared with controls (p < 0.001). Serum levels of resistin went hand in hand with disease severity as they were significantly higher in moderate-severe than mild persistent AR. In addition, they correlated positively with nasal symptom scores (r = 0.74; p < 0.001). A significant positive correlation was observed between serum levels of resistin and IL-6 (r = 0.358; p = 0.011).

Conclusion

Patients with persistent AR were found to have higher serum levels of resistin, and resistin levels increased with the progress of disease severity. Resistin may represent a novel link between inflammation and AR.

Modelling the growth of Japanese eel Anguilla japonica in the lower reach of the Kao-Ping River, southern Taiwan: an information theory approach

Information theory was applied to select the best model fitting total length (L(T))-at-age data and calculate the averaged model for Japanese eel Anguilla japonica compiled from published literature and the differences in growth between sexes were examined. Five candidate growth models were the von Bertalanffy, generalized von Bertalanffy, Gompertz, logistic and power models. The von Bertalanffy growth model with sex-specific coefficients was best supported by the data and nearly overlapped the averaged growth model based on Akaike weights, indicating a similar fit to the data. The Gompertz, generalized von Bertalanffy and power growth models were also substantially supported by the data. The L(T) at age of A. japonica were larger in females than in males according to the averaged growth mode, suggesting a sexual dimorphism in growth. Model inferences based on information theory, which deal with uncertainty in model selection and robust parameter estimates, are recommended for modelling the growth of A. japonica.

Association of interleukin-10 A-592C polymorphism in Taiwanese children with Kawasaki disease

Elevated serum levels of interleukin-10 (IL-10) have been reported in patients with Kawasaki disease (KD). IL-10 reduces the inflammatory actions of macrophages and T cells and it may play a significant role in the regulation of inflammatory vascular damage associated with systemic vasculitis. The aim of this study was to examine whether -592 IL-10 promoter polymorphism is a susceptibility or severity marker of KD in Chinese patients in Taiwan. The study included 105 KD patients and 100 normal controls. Genotype and allelic frequencies for the IL-10 gene polymorphism in both groups were compared. There were no significant between-group differences in the genotype distribution of IL-10 A-592C gene polymorphism (P=0.08). However, the frequency of the -592*A allele was significantly increased in the patients with KD compared with controls (71.9% vs. 61.0%, P=0.019). The odds ratio for developing KD in individuals with IL-10-592*A allele was 1.64 (95% confidence interval, 1.06-2.52) compared to individuals with the IL-10-592*C allele. No significant difference was observed in the genotype and allelic frequencies for the IL-10 A-592C polymorphism between patients with and without coronary artery lesions. The IL-10-592*A allele may be involved in the development of KD in Taiwanese children.

Interleukin-18 gene 105A/C genetic polymorphism is associated with the susceptibility of Kawasaki disease

Interleukin-18 (IL-18)-656T/G, -607A/C, and -137C/G promoter polymorphisms had been reported associated with Kawasaki disease (KD). An IL-18 genetic A/C polymorphism at coding position 105 (rs549908) has been linked with asthma, rheumatoid, and systemic lupus erythematosus. We tested a hypothesis that the IL-18 105A/C genetic polymorphism confers KD susceptibility. Study participants were Taiwanese KD patients and a healthy control group. Our data indicated that the frequency of C allele was significantly higher in the patient group (13.9%) than in the control group (2.7%; P<0.0001, odds ratio [OR]=5.93; 95% confidence interval [CI]=2.57-13.73). Therefore, persons with the C allele may have higher risk of developing KD. In addition, compared with the haplotype frequencies between case and control groups, the KD patients with TACC haplotype appeared to be a significant "at-risk" haplotype compared with other haplotypes (OR: 4.62, 95% CI: 1.71-12.43; P=0.001). KD patient with the TAGA haplotype appeared to be a significant "protective" haplotype compared with other haplotypes (OR: 0.51, 95% CI:0.29-0.89; P=0.017). Our results suggest that 105A/C polymorphism and the haplotypes in IL-18 gene are associated with the risk of KD in Taiwanese population.

Functional genomic analysis identified epidermal growth factor receptor activation as the most common genetic event in oral squamous cell carcinoma

A 250K single-nucleotide polymorphism array was used to study subchromosomal alterations in oral squamous cell carcinoma (OSCC). The most frequent amplification was found at 7p11.2 in 9 of 29 (31%) oral cancer patients. Minimal genomic mapping verified a unique amplicon spanning from 54.6 to 55.3 Mb on chromosome 7, which contains SEC61G and epidermal growth factor receptor (EGFR). Results from fluorescence in situ hybridization, transcriptome, and immunohistochemistry analyses indicated that the expression level of EGFR, but not of SEC61G, was up-regulated and tightly correlated with DNA copy number in 7p11.2 amplified tumors. Among the members of the erbB family, EGFR (HER1) was found to be the most frequently amplified and highly expressed gene in both human and mouse oral tumors (P < 0.01). Genes for downstream effectors of EGFR, including KRAS, mitogen-activated protein kinase 1, and CCND1, were also found amplified or mutated, which resulted in activation of EGFR signaling in 55% of OSCC patients. Head and neck squamous cancer cells with different EGFR expression levels showed differential sensitivity to antitumor effects of AG1478, a potent EGFR inhibitor. AG1478-induced EGFR inactivation significantly suppressed tumor development and progression in a mouse oral cancer model. Our data suggest that EGFR signaling is important in oral cancer development and that anti-EGFR therapy would benefit patients who carry the 7p11.2 amplicon in their tumors.

Nosocomial outbreak of infection with multidrug-resistant Acinetobacter baumannii in a medical center in Taiwan

OBJECTIVE

To investigate a nosocomial outbreak of infection with multidrug-resistant (MDR) Acinetobacter baumannii in the intensive care units at China Medical University Hospital in Taiwan.

DESIGN

Prospective outbreak investigation.

SETTING

Three intensive care units in a 2,000-bed university hospital in Taichung, Taiwan.

METHODS

Thirty-eight stable patients in 3 intensive care units, all of whom had undergone an invasive procedure, were enrolled in our study. Ninety-four A. baumannii strains were isolated from the patients or the environment in the 3 intensive care units, during the period from January 1 through December 31, 2006. We characterized A. baumannii isolates by use of repetitive extragenic palindromic-polymerase chain reaction (REP-PCR) and random amplified polymorphic DNA (RAPD) fingerprinting. The clinical characteristics of the source patients and the environment were noted.

RESULTS

All of the clinical isolates were determined to belong to the same epidemic strain of MDR A. baumannii by the use of antimicrobial susceptibility tests, REP-PCR, and RAPD fingerprinting. All patients involved in the infection outbreak had undergone an invasive procedure. The outbreak strain was also isolated from the environment and the equipment in the intensive care units. Moreover, an environmental survey of one of the intensive care units found that both the patients and the environment harbored the same outbreak strain.

CONCLUSION

The outbreak strain of A. baumannii might have been transmitted among medical staff and administration equipment. Routine and aggressive environmental and equipment disinfection is essential for preventing recurrent outbreaks of nosocomial infection with MDR A. baumannii.

Baculovirus-derived hemagglutinin vaccine protects chickens from lethal homologous virus H5N1 challenge

Since outbreaks of highly pathogenic avian influenza (HPAI) in both human and poultry from 2003, it is critical to have effective vaccines. A cDNA fragment coding the entire hemagglutinin (HA) gene derived from an H5N1 strain (A/duck/China/E319-2/03) was cloned and expressed using the baculovirus system. Two weeks after receiving two doses of recombinant HA (rHA) vaccines, chickens develop high antibody response for hemagglutination inhibition (HI) at titer 7.2 log(2). Challenge studies revealed that vaccinated chickens with HI titers greater than 3 log(2) could have immunoprotection against the same HPAI H5N1 strain virus challenge through intranasal route. Additionally, HI titer of 5 log(2) determined whether the live viruses could not be detected from oropharyngeal, cloacal discharge or in tissues. This result suggests that the rHA expressed from baculovirus system could be a candidate for the development of a safe and efficient subunit vaccine for HPAI (H5N1).

Analysis of ERCC2/XPD functional polymorphisms in systemic lupus erythematosus

Sunlight/ultraviolet (UV) irradiation has been recognized as an important risk factor for developing systemic lupus erythematosus (SLE). However, the interpretation of genetic variations involved in UV-light sensitivity is largely unknown. Recent studies indicated that two genetic variations of ERCC2/XPD gene (rs1799793 in exon 10 and rs13181 in exon 23) have been found to exert negative influences on nucleotide excision repair system. To analyse the possible contribution of the ERCC2/XPD functional single nucleotide polymorphisms in genetic susceptibility to SLE, the rs13181 and rs1799793 SNPs in ERCC2/XPD were genotyped by polymerase chain reaction followed by restriction fragment length polymorphism analysis. Association was studied by case-control analyses using samples from 172 SLE patients and 160 healthy controls. Haplotype analysis was performed to detect the association with genetic predisposition to SLE and the clinical features. Although these two functional genetic variations are linked to several immune dysfunction-induced diseases, no statistically significant differences in allele or genotype frequencies were observed between SLE patients and controls. Haplotype analysis showed that none of ERCC2/XPD haplotypes was associated with the incidence of SLE disease, nor the preference of clinical features. In conclusion, the ERCC2/XPD functional polymorphisms analysed in this study showed no association in genetic susceptibility to SLE.

Gold nanoparticle-based RT-PCR and real-time quantitative RT-PCR assays for detection of Japanese encephalitis virus

Virus isolation and antibody detection are routinely used for diagnosis of Japanese encephalitis virus (JEV) infection, but the low level of transient viremia in some JE patients makes JEV isolation from clinical and surveillance samples very difficult. We describe the use of gold nanoparticle-based RT-PCR and real-time quantitative RT-PCR assays for detection of JEV from its RNA genome. We tested the effect of gold nanoparticles on four different PCR systems, including conventional PCR, reverse-transcription PCR (RT-PCR), and SYBR green real-time PCR and RT-PCR assays for diagnosis in the acute phase of JEV infection. Gold nanoparticles increased the amplification yield of the PCR product and shortened the PCR time compared to the conventional reaction. In addition, nanogold-based real-time RT-PCR showed a linear relationship between Ct and template amount using ten-fold dilutions of JEV. The nanogold-based RT-PCR and real-time quantitative RT-PCR assays were able to detect low levels (1-10 000 copies) of the JEV RNA genomes extracted from culture medium or whole blood, providing early diagnostic tools for the detection of low-level viremia in the acute-phase infection. The assays described here were simple, sensitive, and rapid approaches for detection and quantitation of JEV in tissue cultured samples as well as clinical samples.

Interferon antagonist function of Japanese encephalitis virus NS4A and its interaction with DEAD-box RNA helicase DDX42

The interferon (IFN) antagonists of Japanese encephalitis virus (JEV) proteins contribute to the JE pathogenesis. Most flavivirus non-structural (NS) proteins correlate with virus-induced inflammation and immune escape. NS4A proteins of West Nile virus and dengue type 2 virus have been demonstrated to inhibit IFN signaling. In this study, JEV NS4A without the C-terminal 2K domain has been demonstrated to partially block activation of an IFN-stimulated response element (ISRE)-based cis-reporter by IFN-alpha/beta. In addition, JEV NS4A significantly inhibited the phosphorylation levels of STAT1 and STAT2, but not TYK2 in the IFN-treated cells. Moreover, the N-terminus of a RNA helicase DDX42 protein identified using a phage display human brain cDNA library have been demonstrated to specifically bind to JEV NS4A in vitro using a co-immunoprecipitation assay. The interaction between JEV NS4A and RNA helicase DDX42 showed partial co-localization in human medulloblastoma TE-671 cells by confocal microscopy. Importantly, the expression of N-terminal DDX42 is able to overcome JEV-induced antagonism of IFN responses. Therefore, these results show that JEV NS4A without the C-terminal 2K domain is associated with modulation of the IFN response and the interaction of JEV NS4A with RNA helicase DDX42 could be important for JE pathogenesis.

Type I IFN induced IL1-Ra expression in hepatocytes is mediated by activating STAT6 through the formation of STAT2: STAT6 heterodimer

The biological activities of type I interferons (IFNs) are mediated by their binding to a heterodimer receptor complex (IFNAR1 and IFNAR2), resulting in the activation of the JAK (JAK1 and TYK2)-STAT (1, 2, 3, 5 isotypes) signalling pathway. Although several studies have indicated that IFN-alpha and IFN-beta can activate complexes containing STAT6, the biological role of this activation is still unknown. We found that exposure of hepatoma cells (HuH7 and Hep3B) to IFN-alpha or IFN-beta led to the activation of STAT6. Activated STAT6 in turn induced the formation of STAT2: STAT6 complexes, which led to the secretion of IL-1Ra. The activation of STAT6 by type I IFN in hepatocytes was mediated by JAK1 and Tyk2. In addition, IFN-alpha or IFN-beta significantly enhanced the stimulatory effect of IL-1beta on production of IL-1Ra. The present study suggests a novel function of IFN-alpha and IFN-beta signalling in human hepatocytes. Our results provide evidence for the mechanism how IFN-alpha and IFN-beta modulate inflammatory responses through activation of STAT6 and production of secreted IL-1Ra.

Inhibition of Helicobacter pylori-induced inflammation in human gastric epithelial AGS cells by Phyllanthus urinaria extracts

AIM OF THE STUDY

Helicobacter pylori is linked to a majority of peptic ulcers and to some types of gastric cancer, and its resistance to antibiotic treatment is now found worldwide. This study is aimed at evaluating the antimicrobial activity of Phyllanthus urinaria Linnea (Euphorbiaceae), chloroform (PUC) and methanol (PUM) extracts, and its eight isolates on H. pylori-infected human gastric epithelial AGS cells.

MATERIALS AND METHODS

The in vitro anti-bacterial activity of P. urinaria chloroform (PUC) and methanol (PUM) extracts, and its eight isolates were determined. Additional experiments were also performed to know the PUC and PUM ability to inhibit the H. pylori adhesion to and invasion of AGS cells, in addition to the effect of PUC on NF-kappaB activity as well as IL-8 synthesis during H. pylori infection of AGS cells.

RESULTS

The results revealed that crude extracts PUC and PUM showed potent antimicrobial activity against H. pylori than pure isolates. On the other hand, in vitroH. pylori-infection model revealed that the inhibition of bacterial adhesion and invasion to AGS cells has dramatically reduced by treatment of extract PUC, while PUM has the same moderate effect. Furthermore, H. pylori-induced nuclear factor (NF)-kappaB activation, and the subsequent release of interleukin (IL)-8 in AGS cells were also inhibited by the extract PUC.

CONCLUSIONS

These results open the possibility of considering P. urinaria a chemopreventive agent for peptic ulcer or gastric cancer, but this bioactivity should be confirmed in vivo in the future.

Aloe-emodin is an interferon-inducing agent with antiviral activity against Japanese encephalitis virus and enterovirus 71

In this study, aloe-emodin was identified as a potential interferon (IFN)-inducer by screening compounds from Chinese herbal medicine. Aloe-emodin showed low cytotoxicity to human HL-CZ promonocyte cells and TE-671 medulloblastoma cells and significantly activated interferon-stimulated response element (ISRE) and gamma-activated sequence (GAS)-driven cis-reporting systems. Moreover, aloe-emodin upregulated expression of IFN-stimulated genes such as dsRNA-activated protein kinase and 2′,5′-oligoisoadenylate synthase. Aloe-emodin resulted in significant activation of nitric oxide production. The antiviral activity of aloe-emodin against Japanese encephalitis virus (JEV) and enterovirus 71 (EV71) was evaluated using dose- and time-dependent plaque reduction assays in HL-CZ cells and TE-671 cells. The 50% inhibitory concentration (IC₅₀) of aloe-emodin ranged from 0.50 μg/mL to 1.51 μg/mL for JEV and from 0.14 μg/mL to 0.52 μg/mL for EV71. Aloe-emodin showed clearly potent virus inhibitory abilities and achieved high therapeutic indices, in particular for HL-CZ cells. Therefore, the study demonstrated dose- and time-dependent actions of aloe-emodin on the inhibition of JEV and EV71 replication via IFN signalling responses.

Influence of interleukin 18 promoter polymorphisms in susceptibility to Kawasaki disease in Taiwan

OBJECTIVE

Proinflammatory cytokines such as interferon-gamma (IFN-gamma) play an important role in the pathogenesis of Kawasaki disease (KD). Interleukin 18 (IL-18) plays a pivotal role in the T helper 1 (Th1)-type response, principally owing to its ability to induce IFN-gamma production. We assessed potential associations between functional IL-18 gene promoter polymorphisms and susceptibility to KD, in addition to clinical features of KD in individuals from Taiwan.

METHODS

One hundred forty-six patients with KD and 136 ethnically matched controls from the same geographic area were genotyped for IL-18 -656T/G, -607A/C, and -137C/G promoter polymorphisms.

RESULTS

No significant differences in allele and genotype frequencies were found between KD patients and controls for any of the IL-18 polymorphisms investigated. When we compared the overall distribution of haplotype frequencies between KD patients and controls, a significant difference was observed (p <0.0001). In addition, the frequency of the GCG haplotype was significantly higher (p = 0.00001, pc = 0.00004; OR 20.8, 95% CI 3.05-142.3), whereas the frequency of the TAG haplotype was significantly lower in KD patients compared with controls (p = 0.0001, pc = 0.0004; OR 0.35, 95% CI 0.19-0.61). No significant associations were found for comparisons of KD patients to those with and without coronary artery lesions.

CONCLUSION

Our results suggest a potential implication of IL-18 promoter polymorphisms in susceptibility to KD in Taiwan.

The Separative Bioreactor: A Continuous Separation Process for the Simultaneous Production and Direct Capture of Organic Acids

The replacement of petrochemicals with biobased chemicals requires efficient bioprocesses, biocatalysis, and product recovery. Biocatalysis (e.g., enzyme conversion and fermentation) offers an attractive alternative to chemical processing because biocatalysis utilize renewable feedstocks under benign reaction conditions. One class of chemical products that could be produced in large volumes by biocatalysis is organic acids. However, biocatalytic reactions to produce organic acids typically result in only dilute concentrations of the product because of product inhibition and acidification that drives the reaction pH outside of the optimal range for the biocatalyst. Buffering or neutralization results in formation of the acid salt rather than the acid, which requires further processing to recover the free acid product. To address these barriers to biocatalytic organic acid production, we developed the "separative bioreactor" based on resin wafer electrodeionization, which is an electro-deionization platform that uses resin wafers fabricated from ion exchange resins. The separative bioreactor simultaneously separates the organic acid from the biocatalyst as it is produced, thus it avoids product inhibition enhancing reaction rates. In addition, the separative bioreactor recovers the product in its acid form to avoid neutralization. The instantaneous separation of acid upon formation in the separative bioreactor is one of the first truly one-step systems for producing organic acids. The separative bioreactor was demonstrated with two systems. In the first demonstration, the enzyme glucose fructose oxidoreductase (GFOR) was immobilized in the reactor and later regenerated in situ. GFOR produced gluconic acid (in its acid form) continuously for 7 days with production rates up to 1000 mg/L/hr at >99% product recovery and GFOR reactivity >30mg gluconic acid/mg GFOR/hour. In the second demonstration, the E. coli strain CSM1 produced lactic acid for up to 24 hours with a productivity of >200 mg/L/hr and almost 100% product recovery.

Functional determinants of NS2B for activation of Japanese encephalitis virus NS3 protease

Japanese encephalitis virus (JEV) is a mosquito-borne flavivirus, causing severe central nerve system diseases without specific treatments. The NS2B-NS3 protease of flaviviruses mediates several cleavages on the flavivirus polyprotein, being believed to be a target for antiviral therapy. NS2B is the cofactor of the viral serine protease, correlating with stabilization and substrate recognition of the NS3 protease. In this study, we investigate the functional determinants in the JEV NS2B for the activation of the NS3 protease. Cis- and trans-cleavage assays of the deletions at the N-terminal of NS2B demonstrated that the NS2B residues Ser(46) to Ile(60) were the essential region required for both cis and trans activity of the NS3 protease. In addition, alanine substitution at the residues Trp53, Glu55, and Arg56 in NS2B significantly reduced the cis- and trans-cleavage activities of the NS3 protease. Sequence alignment and modeled structures suggested that functional determinants at the JEV NS2B residues Ser46 to Ile60, particularly in Trp53, Glu55 and Arg56 could play an important configuration required for the activity of the flavivirus NS3 protease. Our results might be useful for development of inhibitors that block the interaction between NS2B and NS3.