Mitochondrial abnormalities in tumor necrosis factor-alpha-induced heart failure are associated with impaired DNA repair activity

BACKGROUND

Recent studies suggest that mutations in cardiac mitochondrial DNA (mtDNA) may contribute to the development of dilated cardiomyopathy. The mechanisms that regulate those mutations, however, remain undefined. Thus, we studied cardiac mtDNA repair mechanisms, mtDNA damage, and mitochondrial structure and function in mice with heart failure secondary to overexpression of TNF-alpha (TNF1.6 mice).

METHODS AND RESULTS

We studied mtDNA repair by measuring the uracil DNA glycosylase (mtUDG) and base excision repair activities. mtDNA damage was assessed by Southern blot of Fpg protein-digested mtDNA. Mitochondrial ultrastructural changes were examined by electron microscopy, and function by cytochrome c oxidase and succinate dehydrogenase activity assays. The results showed that both mtUDG and base excision repair activities were significantly reduced in TNF1.6 mouse heart. Fpg-sensitive sites were markedly increased in TNF1.6 mouse cardiac mtDNA, suggesting increased mtDNA damage. Mitochondrial function as demonstrated by cardiac cytochrome c oxidase activity was also markedly reduced. Cardiac ATP content was not changed, however, suggesting a shift from oxidative phosphorylation to glycolysis, as shown by increased LDH and ALT activities and lactate/pyruvate ratio. Ultrastructurally, the TNF1.6 mouse cardiac mitochondria became irregular in shape and smaller, and the cristae were decreased and appeared disorganized, with breaks.

CONCLUSIONS

These results suggest that mtDNA mutations and mitochondrial structural and functional alterations in TNF-alpha-induced heart failure may be associated with reduced mtDNA repair activity, and the pathophysiological effects of TNF-alpha on the heart may be mediated, at least in part, through these changes in mitochondria.

Vaccination with allogeneic dendritic cells fused to carcinoma cells induces antitumor immunity in MUC1 transgenic mice

Fusions of autologous tumor cells with allogeneic dendritic cells (DC) represent an approach for the induction of antitumor immunity. In the present studies, we investigated the antitumor effects of vaccinating MUC1-transgenic (MUC1.Tg) mice with MC38/MUC1 carcinoma cells fused to allogeneic DC from BALB/c mice (allo-DC, H-2(d)) or syngeneic DC from C57BL/6 mice (syn-DC, H-2(b)). Both allo and syn fusion cells (FC/MUC1) expressed MHC class II, costimulatory molecules, and the MUC1 antigen. Allo-FC/MUC1 exhibited dual expression of MHC class I haplotypes (H-2(d)/H-2(b))and MUC1 antigen. By contrast, only H-2(b) and MUC1 antigen were expressed by syn-FC/MUC1. CTLs from MUC1.Tg mice immunized with allo- or syn-FC/MUC1 fusion cells lysed MC38/MUC1 targets. Moreover, immunization with allo- or syn-FC/MUC1 was effective in eliminating established MUC1-positive pulmonary metastases in MUC1.Tg mice. These results indicate that immunization of MUC1.Tg mice with syn- or allo-FC/MUC1 is effective in reversing immunologic unresponsiveness to MUC1 antigen and inducing immunity against MUC1-positive tumors. The findings in the present study have broader clinical implications for fusion cell vaccines.

[Relation between transcatheter arterial chemoembolization and time of death in patients with hepatic carcinoma]

OBJECTIVE

To evaluate the relationship between transcatheter arterial chemoembolization (TACE) and time of death in hepatic carcinoma patients.

METHODS

One hundred and ninety-five patients (male 188, female 7) with liver cancer underwent TACE with patients dying at different intervals after treatment. Dose of antitumor drugs, amount of iodized oil, liver function, size, recurrence of surgical resection, pattern of tumor, metastasis, presence of portal vein thrombosis, post TACE relapse, post TACE liver function and AFP, etc, altogether 15 variables were subjected to statistical analysis with the Cox's hazard proportional model.

RESULTS

According to univariate and forward stepwise regression analysis, factors associated with significantly worse survival were diffused type, multi-nodular growth of tumor, and tumor embolus in the portal vein (P < 0.0001). Before death, most patients had symptoms of chest oppression, shortness of breath, ascites, abdominal distension, jaundice, hepatic failure and hematemesis. Causes of death were hepatic coma (27.2%, n = 53), hepatic failure (23.1%, n = 45), hemorrhage from the digestive tract (36.9%, n = 72), multiple organ failure (5.1%, n = 10) and others (7.2%, n = 14).

CONCLUSION

Several factors of TACE may lead to failure in liver function and death. TACE may hasten death in patients with severe liver functional embarrassment. Before instituting TACE, careful weighing the pros and cons of the general condition and liver function is important for patients with portal vein embolism, multiple tumors or diffused lesions. Tolerance of liver to the drug, time, dose and method of treatment should be meticulously and carefully planned. Post TACE protection of liver is also very important.

Automated construction of high-density comparative maps between rat, human, and mouse

Animal models have been used primarily as surrogates for humans, having similar disease-based phenotypes. Genomic organization also tends to be conserved between species, leading to the generation of comparative genome maps. The emergence of radiation hybrid (RH) maps, coupled with the large numbers of available Expressed Sequence Tags (ESTs), has revolutionized the way comparative maps can be built. We used publicly available rat, mouse, and human data to identify genes and ESTs with interspecies sequence identity (homology), identified their UniGene relationships, and incorporated their RH map positions to build integrated comparative maps with >2100 homologous UniGenes mapped in more than one species (approximately 6% of all mammalian genes). The generation of these maps is iterative and labor intensive; therefore, we developed a series of computer tools (not described here) based on our algorithm that identifies anchors between species and produces printable and on-line clickable comparative maps that link to a wide variety of useful tools and databases. The maps were constructed using sequence-based comparisons, thus creating "hooks" for further sequence-based annotation of human, mouse, and rat sequences. Currently, this map enables investigators to link the physiology of the rat with the genetics of the mouse and the clinical significance of the human.

Human thrombin and FXa mediate porcine endothelial cell activation; modulation by expression of TFPI-CD4 and hirudin-CD4 fusion proteins

Aside from their critical role in thrombosis, activated coagulation factors also have inflammatory properties and these may be important during delayed xenograft rejection (DXR). This study assessed whether porcine EC could be activated by factor Xa (FXa) and thrombin (FIIa) and whether expression of tissue factor pathway inhibitor (TFPI)-CD4 and hirudin-CD4 fusion proteins could prevent such activation. Incubation of porcine EC with human FXa and FIIa induced cell surface expression of E-selectin, VCAM and tissue factor (TF) in a time-dependent and concentration-dependent manner. In contrast, porcine EC transfected with a human TFPI-CD4 fusion protein were selectively resistant to these pro-inflammatory effects of FXa but not FIIa. Likewise, the transfectants expressing the hirudin-CD4 fusion protein were selectively resistant to the pro-inflammatory effects of FIIa but not those of FXa. When combined, the FXa and FIIa had an additive effect on the activation of control EC. In contrast, coexpression of both hirudin-CD4 and TFPI-CD4 fusion proteins completely inhibited the upregulation of VCAM with the FXa/FIIa mix. These results indicate that expression of novel anticoagulant fusion proteins on the surface of porcine EC can protect against EC activation induced by human coagulation factors FXa and FIIa. In vivo, we anticipate that expression of these fusion proteins on the endothelium of transplanted xenografts, besides preventing intravascular thrombosis, will also protect against EC activation induced by trace amounts of FIIa and FXa, thereby further protecting the grafts from DXR.

SOM integrated with CCA for the feature map and classification of complex chemical patterns

Considering that the two-dimensional (2D) feature map of the high-dimensional chemical patterns can more concisely and efficiently represent the pattern characteristic, a new procedure integrating self-organizing map (SOM) networks with correlative component analysis (CCA) is proposed. Firstly, CCA was used to identify the most important classification characteristics (CCs) from the original high-dimensional chemical pattern information. Then, the SOM maps the first several CCs, which include the most useful information for pattern classification, onto a 2D plane, on which the pattern classification feature is concisely represented. To improve the learning efficiency of SOM networks, two new algorithms for dynamically adjusting the learning rate and the range of neighborhood around the winning unit were further worked out. Besides, a convenient method for detecting the topologic nature of SOM results was proposed. Finally, a typical example of mapping two classes natural spearmint essence was employed to verify the effectiveness of the new approach. The feature-topology-preserving (FTP) map obtained can well represent the classification of original patterns and is much better than what obtained by SOM alone.

Inhibitory effects of rosa roxburghii tratt juice on in vitro oxidative modification of low density lipoprotein and on the macrophage growth and cellular cholesteryl ester accumulation induced by oxidized low density lipoprotein

BACKGROUND

Rosa roxburghii tratt juice (RRTJ) administration has been shown to significantly ameliorate atherosclerotic diseases in cholesterol-fed animals. However, the mechanism for the antiatherogenic effect of RRTJ is not clear.

METHODS

We investigated the effects of RRTJ on in vitro oxidative modification of LDL and on LDL-induced macrophage growth and cellular cholesteryl ester (CE) accumulation. The effects of RRTJ on LDL oxidative modification were assessed by relative electrophoretic migration, thiobarbituric acid-reactive substance (TBARS) content, and the formation of conjugated dienes. The inhibition of RRTJ on oxidized LDL (Ox-LDL)-induced murine peritoneal macrophage growth was evaluated by a cell-counting assay and an MTT assay. The effect of RRTJ on Ox-LDL-induced cellular CE accumulation was examined after macrophages were incubated with Ox-LDL in the presence of RRTJ. To clarify the mechanism of the inhibitory effect of RRTJ on Ox-LDL-induced CE accumulation in macrophages, its capacity for cholesterol efflux from macrophage-derived foam cells were examined.

RESULTS

We showed that RRTJ significantly reduced LDL oxidative susceptibility. In addition, RRTJ effectively suppressed Ox-LDL-induced macrophage growth and especially Ox-LDL-induced CE accumulation in murine peritoneal macrophages by promoting cellular cholesterol efflux.

CONCLUSION

These results indicated that RRTJ exerted its antiatherogenic effects largely due to its ability to inhibit the oxidative modification of LDL and to suppress the formation of foam cells.

Negative control of p53 by Sir2alpha promotes cell survival under stress

The NAD-dependent histone deacetylation of Sir2 connects cellular metabolism with gene silencing as well as aging in yeast. Here, we show that mammalian Sir2alpha physically interacts with p53 and attenuates p53-mediated functions. Nicotinamide (Vitamin B3) inhibits an NAD-dependent p53 deacetylation induced by Sir2alpha, and also enhances the p53 acetylation levels in vivo. Furthermore, Sir2alpha represses p53-dependent apoptosis in response to DNA damage and oxidative stress, whereas expression of a Sir2alpha point mutant increases the sensitivity of cells in the stress response. Thus, our findings implicate a p53 regulatory pathway mediated by mammalian Sir2alpha. These results have significant implications regarding an important role for Sir2alpha in modulating the sensitivity of cells in p53-dependent apoptotic response and the possible effect in cancer therapy.

[An association analysis of apolipoprotein E genotypes with Alzheimer's disease in Chinese population]

OBJECTIVE

To analyse the association of apolipoprotein E genotypes with Alzheimer's disease in Chinese population.

METHODS

Using PCR and restriction enzyme digestion, we have analyzed ApoE allele frequency of Alzheimer's disease (AD) patients and healthy controls.

RESULTS

Among the 56 cases of AD, the frequency of ApoE epsilon 2, ApoE epsilon 3, ApoE epsilon 4 are 3 (2.7%), 84 (75.0%), 25 (22.3%) respectively, while in the 67 controls they are 9 (6.7%), 115 (85.8%), 10 (7.5%) respectively. The frequencies of the two groups have significant difference (P < 0.01) and the frequency of ApoE epsilon 4 allele is higher in AD than that in the health controls and the statistical treatment suggest that there is significant difference (chi 2 = 10.99, P < 0.01, OR = 3.59, 95% CI = 1.54-8.41). The frequency of the ApoE epsilon 3 is lower in AD than that in the health controls and the difference is also statistically significant(P < 0.05).

CONCLUSIONS

Our results are consistent with previous work in that proving the ApoE epsilon 4 allele is one of the risk factors of AD. The results also provide a support for the protection effect of ApoE epsilon 3 allele in developing AD.

Joint action of chemicals in algal toxicity tests: influence of response level and dose-response regression model

The joint toxicity of nonylamine and decylamine and of atrazine and decylamine was evaluated in assays with the green alga Selenastrum capricornutum based on an isobologram method. In this method, curves of constant response, isoboles, are plotted versus concentrations of two toxicants. The response parameter was growth rate based on biomass, and several response levels were used. Dose-response curves were developed for dilution series using fixed ratios between concentrations in toxic units of the compounds. Probit and Weibull dose-response curves were then determined by nonlinear regression. A model for isoboles for partially similar action was used when applicable. The no-effect concentration (NEC or EC0) was estimated based on a newly proposed model containing median effective concentration (EC50) and EC0 as explicit variables. Results show that nonylamine and decylamine are nearly concentration additive at EC50 and EC10 (similarity parameter lambda = 0.70-0.76) and to a lesser extent at EC0. By contrast, the mixtures of atrazine and decylamine show antagonism in that atrazine acts as an antidote to decylamine. The shapes of these isoboles are independent of response level. The EC50 values (mg/L) for chemicals acting singly were 0.090 (nonylamine), 0.039 to 0.044 (decylamine), and 0.225 (atrazine). In order to determine NEC effectively, the level of inhibition must be fairly low, with observed growth rates between 0.6 and 1.0 times the average growth rate of the controls.

Effects of CCK2 receptor blockade on growth parameters in gastrointestinal tract and pancreas in rats

Gastrin has a growth-promoting effect on the oxyntic mucosa of the stomach but has been claimed also to affect other parts of the gastrointestinal tract and pancreas. This report describes the effects of the cholecystokinin, (CCK2) receptor antagonists YM022 and YF476 on various growth parameters in the gastrointestinal tract and pancreas of the rat. YM022 and YF476 were given subcutaneously in doses known to produce maximum and sustained CCK2 receptor blockade. The body weight was not affected. However, the oxyntic mucosal weight, thickness and protein and DNA contents were reduced by 15-20% already within 1-2 days and by about 30% after 4-8 weeks of CCK2 receptor blockade. Hence, the response of the oxyntic mucosa to CCK2 receptor blockade was in the form of hypotrophy (reduced protein content) and hypoplasia (reduced DNA content). There were no obvious effects of CCK2 receptor blockade on the intestine or pancreas (nor on liver, kidney or thyroid). The proton pump inhibitor omeprazole was used to induce hypergastrinaemia and was given with or without YM022. Omeprazole treatment for 4 weeks increased the oxyntic mucosal weight and thickness by 15-20%. YM022 prevented these effects. We conclude that while elevated circulating gastrin levels, acting on CCK2 receptors, exert a growth-promoting effect on the oxyntic mucosa (but not elsewhere), normal serum gastrin levels exert a mucosa-preserving effect.

Long-term omeprazole treatment suppresses body weight gain and bone mineralization in young male rats

BACKGROUND

The stomach is rich in endocrine cells, including those producing ghrelin, which is thought to play a role in the control of body growth. Omeprazole treatment is associated with hypergastrinaemia, resulting in growth of the oxyntic mucosa in general and the enterochromaffin-like (ECL) cells in particular. In the present study, we examined the effects of long-term omeprazole treatment on young male rats with respect to body growth and stomach.

METHODS

Male rats (24 days old) were treated with omeprazole (400 micromol/kg/day) or vehicle for 77 days. The body weight was recorded twice per week. At sacrifice, dual-energy X-ray absorptiometry (DXA) was used to assess total bone area, bone mineral content (BMC), bone mineral density (BMD) and body composition (fat and lean body mass). The lengths of the spine and the femur were recorded. The plasma concentrations of gastrin and histamine were determined by radioimmunoassays. The endocrine cells of the stomach were examined by immunocytochemistry.

RESULTS

The body weight gain was suppressed by omeprazole treatment. The bone area, BMC and BMD were reduced, while the lengths of the spine and the femur and the body composition were unchanged. Omeprazole-induced hypergastrinaemia was associated with enlargement of the oxyntic area and with hyperplasia of ECL cells but not of A-like cells and D cells. In contrast, the enterchromaffin (EC) cell density in the antrum was reduced.

CONCLUSIONS

Omeprazole treatment of young male rats reduces body weight and bone mass gain. The densities of ECL cells in the oxyntic mucosa was increased and of the EC cells in the antral mucosa reduced.

Competence development by Haemophilus influenzae is regulated by the availability of nucleic acid precursors

DNA uptake by naturally competent bacteria provides cells with both genetic information and nucleotides. In Haemophilus influenzae, competence development requires both cAMP and an unidentified signal arising under starvation conditions. To investigate this signal, competence induction was examined in media supplemented with nucleic acid precursors. The addition of physiological levels of AMP and GMP reduced competence 200-fold and prevented the normal competence-induced transcription of the essential competence genes comA and rec-2. The rich medium normally used for growth allows only limited competence. Capillary electrophoresis revealed only a subinhibitory amount of AMP and no detectable GMP, and the addition of AMP or GMP to this medium also reduced competence 20- to 100-fold. Neither a functional stringent response system nor a functional phosphoenolpyruvate:glycose phosphotransferase system (PTS) was found to be required for purine-mediated repression. Added cAMP partially restored both transcription of competence genes and competence development, suggesting that purines may reduce the response to cAMP. Potential binding sites for the PurR repressor were identified in several competence genes, suggesting that competence is part of the PUR regulon. These observations are consistent with models of competence regulation, in which depleted purine pools signal the need for nucleotides, and support the hypothesis that competence evolved primarily for nucleotide acquisition.

Identification of sequences in rotavirus mRNAs important for minus strand synthesis using antisense oligonucleotides

The core of the rotavirion consists of three proteins, including the viral RNA polymerase, and 11 segments of double-stranded (ds)RNA. The RNA polymerase of disrupted (open) cores is able to catalyze the synthesis of dsRNA from exogenous viral mRNAs in vitro. In this study, we have identified sequences in exogenous viral mRNAs important for RNA replication using antisense oligonucleotides. The results showed that oligonucleotides complementary to the highly conserved 3'-terminal sequence of rotavirus mRNAs prevented all but basal levels of dsRNA synthesis. Notably, we observed that the addition of oligonucleotides which were complementary to nonconserved sequences present either at the 5'- or 3'-end of a viral mRNA effectively inhibited its replication without interfering with the replication of other viral mRNAs present in the same replication assay. Thus, the nonconserved sequences in rotavirus mRNAs contain gene-specific information that promotes RNA replication. The fact that antisense oligonucleotides inhibited dsRNA synthesis indicates that the strandedness (single- versus double-stranded) and secondary structure of the viral mRNA template are factors that affect the efficiency of minus strand synthesis.

Eye irritation caused by formaldehyde as an indoor air pollution--a controlled human exposure experiment

OBJECTIVE

The present study focuses on health assessment of wood based panels which are widely used in interior decoration practices over the recent years in China. Formaldehyde has been identified as chemical indicator of (IAO) and an indoor air pollutant. To test its health effects experiment was undertaken.

METHOD

A small environmental test chamber (60/L) was used as the generator of emission gas from new panels, and was operating at a temperature of 22.7 +/- 0.6 degrees C and a humidity of 44.4 +/- 2.5% with an air exchange rate of 1.0 +/- 0.15 h-1. On the three experimental days the values of product loading in chamber were 4, 2 and 6 m2/m3, respectively. Eight people were selected randomly from the students and employees of Wuhan Health and Anti-epidemic Station as subjects, with an average age of 21.9 +/- 5.9 years, and a gender ratio of 1:1, and two of them were smokers (one male and one female). The subjects' eyes were exposed to formaldehyde through a pair of goggles. Each goggle had its flow inlet and outlet, and connected to chamber exhaust of emission gas and to an exhaust from the room. The exposure time was very short, just 5 minutes and the formaldehyde doses were at 1.65 +/- 0.01, 2.99 +/- 0.07 and 4.31 +/- 0.02 ppm. A 60-mm linear visual analogue rating scales was used to measure the intensity of sensory eye irritation and a video tape recorder was used to record eye blinking frequency.

RESULTS

The results demonstrated that tests of sensory eye irritation and eye blinking can be used for materials testing, and that a dose-effect as well as a time-variance of the effect can be measured.

CONCLUSION

The tests showed that eye irritation was perceived at all of the three levels.

[Immunological regulations of dendritic cell in abnormal scarring tissue]

OBJECTIVE

To investigate the relationship between dendritic cell(DC) and pathogenesis of abnormal scar.

METHODS

The content of HLA-DR and CD1a molecules of DC, in 6 samples of hypertrophic scar (HS), keloid (K) and normal skin, were determined with the stain of avidin-biotin-peroxidase complex method (ABC). The effect of Triamcinolone Acetonide was evaluated with the measurement of the HLA-DR and CD1a molecules of DC in the epidermis of the HS.

RESULTS

1. The amounts of HLA-DR molecules of the positive DC were 806.67 +/- 101.72 and 870.00 +/- 134.24 in the HS and the K respectively, significantly higher than the controlled normal skin (510.01 +/- 45.17, P < 0.05). HLA-DR molecules showed an abnormal expression in the Kerationcytes and fibroblasts. 2. The amounts of CD1a molecules of the positive DC were 700.00 +/- 97.23 and 780.00 +/- 104.47 in the HS and the K respectively, significantly higher than the controlled normal skin (521.24 +/- 57.87)(P < 0.05). 3. The amounts of the HLA-DR molecules positive DC, in the positive kerationcytes and fibroblasts of hypertrophic scar, treated by Triamcinolone Acetonide, were 476.67 +/- 70.02 and 447.76 +/- 90.03 (P < 0.05) for 3 days and 7 days treatment respectively, significantly lower than the control. The amounts of CD1a molecules positive DC in the epidermis of hypertrophic scar with the injection of Triamcinolone Acetonide were significantly lower in 3 days and 7 days treatment (456.36 +/- 82.88 and 397.18 +/- 99.36, P < 0.05).

CONCLUSION

1. The results, with the high expression of HLA-DR and CD1a molecules, indicate that the HS and the K may have strong immune reactions. 2. Triamcinolone Acetonide may decrease the immune reactions of the HS, through the inhibition of the expressions of HLA-DR and CD1a molecules in the dendritric cell.

[Pre- and post-contrast multiphase helical CT in the diagnosis of hepatic focal nodular hyperplasia]

OBJECTIVE

To analyse the pre- and post-contrast CT findings of liver focal nodular hyperplasia (FNH), so as to improve its diagnostic accuracy.

METHODS

Pre-contrast scan and post-contrast tri-phase scan (arterial phase, portal venous phase and delayed phase) were performed in 21 patients with FNH which were proved surgically and pathologically. Transcatheter arterial angiography was performed in 2 patients.

RESULTS

On pre-contrast scans, 16 of 21 lesions were hypodense, 5 of 21 were isodense. Twelve of 21 lesions showed punctate, streak and radial scar. On the arterial phase scans, all the lesions were markedly and homogeneously enhanced, except for the central scar. Nine of 21 lesions showed dilated and tortuous arteries at the central or peripheral area. On the portal venous phase scans, focal density was decreased, but still showing hyperdense or slightly hyperdense relative to the normal liver. On the delay phase scans, the lesions changed to isodense or slightly hypodense. Enhanced capsule was observed in 3 patients. On the angiography images, dilated arteries and drainage veins were seen.

CONCLUSION

FNH has its special characteristics on the multiphasic helical CT scan. It is of great value in diagnosing the FNH and in choosing the appropriate therapy.

[Cytotoxicity of the strontium-substituted hydroxyapatite evaluated by MTT colorimetry]

This study was conducted to evaluate the cytotoxicity of strontium-substituted hydroxyapatite by methyl thiazolyl tetrazolium (MTT) colorimetry. We used the MTT method to assay the cytotoxicity of the strontium-substituted hydroxyapatite containing different strontium concentrations (1%, 5%, 10%, 100% Sr2+) and the pure hydroxyapatite. The results showed that the cytotoxicity scores of the different materials were grade 0 or grade 1. These led us to the conclusion that strontium-substituted hydroxyapatite has good biocompatibility.

Serum and mucosal immune responses to an inactivated influenza virus vaccine induced by epidermal powder immunization

Both circulating and mucosal antibodies are considered important for protection against infection by influenza virus in humans and animals. However, current inactivated vaccines administered by intramuscular injection using a syringe and needle elicit primarily circulating antibodies. In this study, we report that epidermal powder immunization (EPI) via a unique powder delivery system elicits both serum and mucosal antibodies to an inactivated influenza virus vaccine. Serum antibody responses to influenza vaccine following EPI were enhanced by codelivery of cholera toxin (CT), a synthetic oligodeoxynucleotide containing immunostimulatory CpG motifs (CpG DNA), or the combination of these two adjuvants. In addition, secretory immunoglobulin A (sIgA) antibodies were detected in the saliva and mucosal lavages of the small intestine, trachea, and vaginal tract, although the titers were much lower than the IgG titers. The local origin of the sIgA antibodies was further shown by measuring antibodies released from cultured tracheal and small intestinal fragments and by detecting antigen-specific IgA-secreting cells in the lamina propria using ELISPOT assays. EPI with a single dose of influenza vaccine containing CT or CT and CpG DNA conferred complete protection against lethal challenges with an influenza virus isolated 30 years ago, whereas a prime and boost immunizations were required for protection in the absence of an adjuvant. The ability to elicit augmented circulating antibody and mucosal antibody responses makes EPI a promising alternative to needle injection for administering vaccines against influenza and other diseases.

Prostate-specific targeting using PSA promoter-based lentiviral vectors

The prostate-specific antigen (PSA) promoter is known to be highly tissue specific. Although its tissue specificity has been confirmed, its efficiency of gene transcription is significantly lower compared to known nonspecific viral promoters. These lower levels of promoter activity therefore pose a problem when developing an efficacious gene vector for prostate cancer gene therapy. Thus, selecting an appropriate therapeutic gene and vector system to carry the gene driven by the PSA promoter (PSAP) is important. In the studies described here, a human immunodeficiency virus (HIV)-1-based lentiviral vector carrying either the enhanced green fluorescent protein (EGFP) reporter or the diphtheria toxin A (DTA) gene was constructed. The results demonstrate that the PSA promoter in a lentiviral vector drives genes in prostate cells with satisfactory efficacy and specificity. The tissue-specific expression of the DTA protein efficiently eradicates LNCaP prostate cells in culture. We also infected prostate cancer cells and control cells carried by nude mice with the EGFP lentiviral vector. Significant numbers of EGFP-positive LNCaP cells were detected in all the mice bearing these tumors, but no EGFP-positive control cells were detected in any other mouse tissue. The high levels of expression in prostate cells, compared with the low levels of background expression in other cells, show that the PSAP-lentiviral vector could be a potential useful tool for gene therapy of metastatic prostate cancer.

Purification and characterization of White Spot syndrome virus (WSSV) produced in an alternate host: crayfish, Cambarus clarkii

Penaeid shrimp is the natural host of White Spot Syndrome Virus (WSSV) that can cause high mortality in the infected hosts. Attempts to obtain sufficient amounts of purified intact WSSV for characterization have been unsuccessful. Using crayfish, Cambarus clarkii as a proliferation system, a large amount of infectious WSSV was reproduced and intact WSSV viral particles were purified with a new isolation medium by ultra-centrifugation. Purified WSSV particles were very sensitive to organic solvents and the detergent, Triton X-100. The size of the rod-shape, somewhat elliptical, intact WSSV was 110-130x260-350 nm with a long, tail-like envelope extension. The naked viral nucleocapsid was about 80x350 nm, and it possessed 15 spiral and cylindrical helices composed of 14 globular capsomers along its long axis, and a 'ring' structure at one terminus. Distinct WSSV genome DNA patterns were obtained when the purified genomic dsDNA of WSSV was digested with five different restriction enzymes (HindIII, XhoI, BamHI, SalI, and SacI). In addition, at least 13 major and distinct protein bands could be observed when purified intact WSSV viruses were separated by SDS-PAGE followed by Coomassie Brilliant R-250 staining. The estimated molecular weights of these proteins were 190, 84, 75, 69, 68, 58, 52, 44, 28, 27.5, 23, 19, and 16 kD, respectively. Both the 44 and 190 kD proteins were easily removed if the hemolymph from the WSSV infected crayfish was transiently treated with 1% Triton X-100 before it was subjected to gradient centrifugation, indicating that both of them are located on the surface of the viral envelope. These characteristics are consistent with WSSV isolated from the penaeid shrimp.