Development of a method for the isolation and culture of astrocytes from the canine cerebral cortex.

BACKGROUND: Astrocytes are considered key players in neuroimmunopathological processes, and they play a certain role in neuroinflammation. Rodent primary astrocyte cultures are commonly used in the study of human neuroinflammation. However, gene sequence homologies are closer between humans and dogs than between humans and rodents. NEW METHOD: We established protocols to isolate astrocytes from the canine forebrain. Cerebral hemispheres of 3-4-week-old dogs were used. The isolation procedure included the use of the Neural Tissue Dissociation Kit P, demyelination by the magnetic bead method, and separation and preparation by differential adhesion. RESULTS: We found a 96% astrocyte purification rate after isolation by differential adhesion. Purified canine astrocytes increased the secretion of interleukin-1ß, interleukin-6, and tumor necrosis factor-alpha, and increased the expression of glial fibrillary acidic protein after lipopolysaccharide stimulation. We sequenced the transcriptome of the purified canine astrocytes and analyzed the differentially expressed genes among the rodent, human, and canine astrocytes. Transcriptome profiling and gene ontology analysis of the genes co-expressed in humans and canines indicate that human and canine astrocytes may be different from their rodent counterparts in terms of mediated interactions with metals. COMPARED WITH THE EXISTING METHODS: The cells prepared by our method allow for the rapid separation of astrocytes with a relatively small resource scheme. The method also retains the cell phenotype and has an in vitro culture lifetime of approximately 2-3 months. CONCLUSION: We established a method for preparing canine astrocytes with high purity, which can be used to study the biological function of astrocytes in vitro.

Experimental infection of Bama miniature pigs with a highly virulent classical swine fever virus.

BACKGROUND: Currently, larger domestic pigs are only animals widely used in vaccine evaluation and pathogenicity study of classical swine fever virus (CSFV). This study was aimed to create an alternative animal experimental infection model of CSFV. RESULTS: Twenty specific-pathogen-free Bama miniature pigs were randomly divided into two groups and rooms, infected and non-infected, and the pigs in the infected group were inoculated intramuscularly with 104, 105 or 106 TCID50 (median tissue culture infective dose) CSFV Shimen strain (n = 5 × 3) or left uninoculated to serve as in-contact pigs (n = 3). The uninfected control pigs (n = 2) were housed in a separate room. Clinical signs, body temperature, viraemia, tissue antigen distribution, pathological changes and seroconversion were monitored. Clinical signs were observed as early as 2 days post-inoculation (dpi) in all infected pigs (though mild in contact pigs), but not non-infected control pigs. All inoculated pigs showed viraemia by 6 dpi. The in-contact pigs showed lower levels of viraemia. At 10 dpi, seroconversion was noted in five of the 15 inoculated pigs. All inoculated or one in-contact pigs died by 15 dpi. CONCLUSIONS: These results show that Bama miniature pigs support productive CSFV infection and display clinical signs and pathological changes consistent with CSFV infections observed in larger domestic pigs.

Expression and prognostic values of Id-1 and Id-3 in gastric adenocarcinoma.

BACKGROUND: Id (inhibitor of differentiation/DNA binding)-1 and -3 are involved in neoangiogenesis; they antagonize basic helix-loop-helix proteins, inhibit differentiation, and enhance cell proliferation. The aim of this study was to investigate Id-1 and -3 expression in gastric tumors and their clinical relevance in gastric cancer. MATERIALS AND METHODS: We investigated Id-1 and Id-3 expression in gastric cancer samples by immunohistochemistry and Western blotting, and further analyzed the relationship between expression of Id-1 and Id-3 and clinicopathologic characteristics. RESULTS: Expression of Id-1 and -3 was found significantly more often in gastric cancers than in matched adjacent nonmalignant tissues. Cancer samples with poor or moderate histologic differentiation showed significantly stronger Id-1 and -3 expression than cancer samples with high differentiation. In cancer samples, strong or moderate expression of Id-3, but not Id-1, was a strong independent predictor for shorter overall survival in multivariate analysis. CONCLUSIONS: The level of Id-1 and -3 protein expression was associated with the malignant potential of gastric tumors. In cancer samples, stronger Id-1 and -3 expression is associated with poor differentiation and more aggressive behavior of tumor cells, resulting in poor clinical outcome. Consequently, Id-3 might be used to independently predict survival of patients with gastric cancer.

EF24 inhibits tumor growth and metastasis via suppressing NF-kappaB dependent pathways in human cholangiocarcinoma.

A synthetic monoketone analog of curcumin, termed 3, 5-bis (2-flurobenzylidene) piperidin-4-one (EF24), has been reported to inhibit the growth of a variety of cancer cells both in vitro and in vivo. However, whether EF24 has anticancer effects on cholangiocarcinoma (CCA) cells and the mechanisms remain to be investigated. The aim of our study was to evaluate the molecular mechanisms underlying the anticancer effects of EF24 on CCA tumor growth and metastasis. Cell proliferation, apoptosis, migration, invasion, tumorigenesis and metastasis were examined. EF24 exhibited time- and dose-dependent inhibitory effects on HuCCT-1, TFK-1 and HuH28 human CCA cell lines. EF24 inhibited CCA cell proliferation, migration, and induced G2/M phase arrest. EF24 induced cell apoptosis along with negative regulation of NF-κB- X-linked inhibitor of apoptosis protein (XIAP) signaling pathway. XIAP inhibition by lentivirus mediated RNA interference enhanced EF24-induced apoptosis, while XIAP overexpression reduced it in CCA cells. In vivo, EF24 significantly suppressed the growth of CCA tumor xenografts and tumor metastasis while displaying low toxicity levels. Our findings indicate that EF24 is a potent antitumor agent that inhibits tumor growth and metastasis by inhibiting NF-κB dependent signaling pathways. EF24 may represent a novel approach for CCA treatment.

Establishment of reverse transcription loop-mediated isothermal amplification for rapid detection and differentiation of canine distemper virus infected and vaccinated animals.

Although widespread vaccination against canine distemper virus (CDV) has been conducted for many decades, several canine distemper outbreaks in vaccinated animals have been reported frequently. In order to detect and differentiate the wild-type and vaccine strains of the CDV from the vaccinated animals, a novel reverse transcription loop-mediated isothermal amplification (RT-LAMP) method was developed. A set of four primers-two internal and two external-were designed to target the H gene for the specific detection of wild-type CDV variants. The CDV-H RT-LAMP assay rapidly amplified the target gene, within 60 min, using a water bath held at a constant temperature of 65°C. The assay was 100-fold more sensitive than conventional RT-PCR, with a detection limit of 10(-1)TCID50ml(-1). The system showed a preference for wild-type CDV, and exhibited less sensitivity to canine parvovirus, canine adenovirus type 1 and type 2, canine coronavirus, and canine parainfluenza virus. The assay was validated using 102 clinical samples obtained from vaccinated dog farms, and the results were comparable to a multiplex nested RT-PCR assay. The specific CDV-H RT-LAMP assay provides a simple, rapid, and sensitive tool for the detection of canines infected with wild-type CDV from canines vaccinated with attenuated vaccine.

Emerging multiple reassortant H5N5 avian influenza viruses in ducks, China, 2008.

Three highly pathogenic H5N5 avian influenza viruses (HPAI), A/duck/Guangdong/wy11/2008 (WY11), A/duck/Guangdong/wy19/2008 (WY19), and A/duck/Guangdong/wy24/2008 (WY24) were isolated from ducks in southern China in April 2008. Here, we characterized these viruses by performing sequencing and phylogenetic analyses of their viral genes, assessing their virulence in ducks and mice, and performing cross-protection experiments in chickens. Sequence analysis revealed that the HA genes of these H5N5 viruses showed 97.1-97.8% homology to A/wild duck/Hunan/211/2005 (H5N1) influenza virus and that their NA genes showed 96.4-96.8% nucleotide identity to the NA gene of A/duck/Hunan/5613/2003 (H6N5) influenza virus, which belongs to the Eurasian lineage. Genotypic analysis indicated that these H5N5 viruses were multiple reassortants among H5N1, H5N2, H6N2, and H6N5 viruses. The analysis of HA clade showed that these H5N5 viruses are clustering into clade 2.3.4. In animal experiments, these H5N5 viruses caused 50% mortality in ducks and 100% mortality in chickens. In cross-protection experiments, the clade 2.3.2 avian influenza vaccine could provide only 75% protection with chickens against H5N5 virus challenge. Moreover, the H5N5 virus replicated efficiently in the lungs of mice, which suggested that the H5N5 viruses have the potential to infect mammalian hosts. Since ducks have served as reassortant vessels, playing pivotal roles in the generation of new subtypes of influenza viruses, it is important to monitor the emergence of this novel subtype of influenza viruses in waterfowl to understand their ecology and evolution and to control the spread of new viruses.

Specific TaqMan probed real-time quantitative RT-PCR methods and their application to differentiate the transcripts of duplicated BF or BLB genes in chicken MHC.

BF and BLB genes of chicken major histocompatibility complex (MHC) are responsible for classical antigen processing and presentation; therefore they play a central role in determining the genetic resistance or susceptibility of different MHC-B haplotypes to some infectious diseases. In this study, we developed specific TaqMan probed real-time quantitative reverse transcription PCR (TaqMan qRT-PCR) methods based on the diagnostic nucleotide polymorphisms present in duplicated BF or BLB genes in B2 and B19 haplotypes. The results showed very similar amplification efficiency but no cross-reaction between the duplicated BF or BLB genes of the same haplotype. Spleen mRNA samples of B2 and B19 chickens were used to validate these TaqMan qRT-PCR methods. We observed that BF2 or BLB2 gene was dominantly transcribed in all B2 and B19 chickens. Our findings verified the impact of diversified promoter sequences on the function of duplicated BF or BLB genes. Hence the principles adopted to establish these specific TaqMan qRT-PCR methods in this study can be applied to differentiate the transcripts of duplicated BF or BLB genes of other MHC-B haplotypes in chicken.

Expression and prognostic value of ING3 in human primary hepatocellular carcinoma.

The tumor-suppressor ING3 has been shown to be involved in tumor transcriptional regulation, apoptosis and the cell cycle. Some studies have demonstrated that ING3 is dysregulated in several types of cancers. However, the expression and function of ING3 in human hepatocellular carcinoma (HCC) remains unclear. The aim of this study is to investigate ING3 expression in hepatic tumors and its clinical relevance in hepatic cancer. The expression of ING3 protein was examined in 120 dissected HCC tissues and 47 liver tissues adjacent to the tumor by immunohistochemical assays and confirmed by Western blot analysis in 20 paired frozen tumor and non-tumor liver tissues. The relationship between ING3 staining and clinico-pathological characteristics of HCC was further analyzed. The mRNA expression of ING3 in the dissected tissues was also analyzed by reverse transcriptase polymerase chain reaction (RT-PCR) and realtime PCR. Both mRNA and protein concentrations of ING3 were found to be downregulated in the majority of HCC tumors in comparison with matched non-tumor hepatic tissues. Analysis of the relationship between ING3 staining and clinico-pathological characteristics of HCC showed that the low expression of ING3 protein is correlated with more aggressive behavior of the tumor. Kaplan-Meier curves demonstrated that patients with a low expression of ING3 have a significantly increased risk of shortened survival time. In addition, multivariate analysis suggested that the level of ING3 expression may be an independent prognostic factor. Our findings indicate that ING3 may be an important marker for human hepatocellular carcinoma progression and prognosis, as well as a potential therapeutic target.