HPV-16 E1, E2 and E6 each complement the Ad5 helper gene set, increasing rAAV2 and wt AAV2 production

Adeno-associated virus type 2 (AAV) is a popular vector for human gene therapy, because of its safety record and ability to express genes long term. Yet large-scale recombinant (r) AAV production remains problematic because of low particle yield. The adenovirus (Ad) and herpes (simplex) virus helper genes for AAV have been widely used and studied, but the helper genes of human papillomavirus (HPV) have not. HPV-16 E1, E2 and E6 help wild-type (wt) AAV productive infection in differentiating keratinocytes, however, HEK293 cells are the standard cell line used for generating rAAV. Here we demonstrate that the three HPV genes were unable to stimulate significant rAAV replication in HEK293 cells when used alone. However, when used in conjunction (complementation) with the standard Ad5 helper gene set, E1, E2 and E6 were each capable of significantly boosting rAAV DNA replication and virus particle yield. Moreover, wt AAV DNA replication and virion yield were also significantly boosted by each HPV gene along with wt Ad5 virus co-infection. Mild-to-moderate changes in rep- and cap-encoded protein levels were evident in the presence of the E1, E2 and E6 genes. Higher wt AAV DNA replication was not matched by similar increases in the levels of rep-encoded protein. Moreover, although rep mRNA was upregulated, cap mRNA was upregulated more. Higher virus yields did correlate most consistently with increased Rep52-, VP3- and VP-related 21/31 kDa species. The observed boost in wt and rAAV production by HPV genes was not unexpected, as the Ad and HPV helper gene sets do not seem to recapitulate each other. These results raise the possibility of generating improved helper gene sets derived from both the Ad and HPV helper gene sets.

Plasma soluble HLA-G is a potential biomarker for diagnosis of colorectal, gastric, esophageal and lung cancer

Human leukocyte antigen-G (HLA-G) is a novel tumor marker and its soluble isoforms produce secretory proteins. Increased soluble HLA-G (sHLA-G) levels have been reported in patients with melanoma, neuroblastoma, lymphoproliferative disorders, breast, ovarian and colorectal carcinoma when compared to healthy controls or subjects with benign neoplasms. The aim of this study is to investigate whether or not plasma sHLA-G can be used as a potential biomarker for cancer diagnosis. We measured plasma sHLA-G levels in 166 patients with early stages of colorectal cancer (CRC, n = 37), gastric cancer (GC, n = 28), esophageal squamous cell carcinoma (ESCC, n = 58) and non-small cell lung cancer (NSCLC, n = 43), and compared them to healthy controls (n = 260) by using a specific HLA-G enzyme-linked immunosorbent assay (ELISA). We found that plasma sHLA-G levels were significantly higher in cancer patients than in healthy controls (all P < 0.0001). The areas under the receiver-operating characteristic (ROC) curves for sHLA-G were 0.97, 0.91, 0.98 and 0.80 for healthy controls vs CRC, GC, ESCC and NSCLC, respectively. At 100% specificity, the highest sensitivity achieved to detect CRC, GC, ESCC and NSCLC was 94% [95% confidence interval (CI), 89-99], 85% (95% CI, 76-94), 91% (95% CI, 88-94) and 51% (95% CI, 43-59) at a cutoff value of 49 U/ml, respectively. These findings suggest that plasma sHLA-G may be a useful molecule in the differential diagnosis of these malignancies against healthy controls.

Patient and doctor perspectives on incorporating smoking cessation into tuberculosis care in Beijing, China

SETTING

Tuberculosis (TB) hospital in Beijing, China.

OBJECTIVE

To describe perspectives of patients and physicians regarding the incorporation of smoking cessation interventions as part of TB treatment.

DESIGN

Seven focus groups were conducted with 39 patients and 17 physicians.

RESULTS

Patients were more receptive to physicians' advice to quit smoking due to increased concerns about their health after becoming ill with TB. However, patients indicated that they might start smoking again after they recovered from TB. Patients' attempts to quit smoking may have been inhibited by exposure to smoking at the TB facility. Physicians had low levels of knowledge regarding the effect of smoking on TB. Many doctors, particularly those who smoked, did not view smoking cessation as an integral part of TB treatment.

CONCLUSION

Despite the presence of a 'teachable moment', TB patients experience significant barriers to quitting smoking. Patient education in TB treatment programs should address the specific effects of smoking on TB and the general health benefits of cessation. Smoke-free policies should be strictly enforced in TB facilities. Successful integration of smoking cessation interventions within TB treatment regimens may require that providers adopt smoking cessation as an essential part of TB treatment.

Hypocretin and its emerging role as a target for treatment of sleep disorders

The neuropeptides hypocretin-1 and -2 (orexin A and B) are critical in the regulation of arousal and maintenance of wakefulness. Understanding the role of the hypocretin system in sleep/wake regulation has come from narcolepsy-cataplexy research. Deficiency of hypocretin results in loss of sleep/wake control with consequent unstable transitions from wakefulness into non-rapid eye movement (REM) and REM sleep, and clinical manifestations including daytime hypersomnolence, sleep attacks, and cataplexy. The hypocretin system regulates sleep/wake control through complex interactions between monoaminergic/cholinergic wake-promoting and GABAergic sleep-promoting neuronal systems. Research for the hypocretin agonist and the hypocretin antagonist for the treatment of sleep disorders has vigorously increased over the past 10 years. This review will focus on the origin, functions, and mechanisms in which the hypocretin system regulates sleep and wakefulness, and discuss its emerging role as a target for the treatment of sleep disorders.

Influence of serum and soluble CD25 (sCD25) on regulatory and effector T-cell function in hepatocellular carcinoma

Our previous studies showed that high levels of soluble CD25 (sCD25) in the serum of patients with hepatocellular carcinoma (HCC) correlated with blunted effector T-cells (Teff) responses, tumour burden and poor survival. Understanding the interactions between Teff, CD4+CD25+ regulatory T cells (Treg) and soluble factors can identify novel therapeutic targets. In this study, we characterize the mechanisms by which HCC serum and sCD25 mediate suppression of Teff and evaluate the effect of sCD25 on the suppression assays with normal healthy control cells (NHC) at a 1:1 Treg to Teff cell ratio to determine whether sCD25 has any impact on Treg suppression. HCC serum and sCD25 suppressed Teff proliferation and downregulated CD25 expression on HCC Teff in a dose-dependent fashion with sCD25 doses above 3000 pg/ml. Treg from HCC and cirrhosis patients suppressed proliferation of target CD4+CD25- Teff in serum-free medium (SFM). HCC Treg showed a higher degree of suppression than cirrhosis-derived Treg. In contrast, Treg from NHC did not suppress target Teff in SFM. However, isolated Treg from all three study subjects (HCC, cirrhosis and NHC) suppressed CD4+CD25- Teff in serum conditions or in the presence of sCD25 in the range 6000-12,000 pg/ml. In conclusion, downregulation of CD25 cell surface expression on Teff is part of the overall suppressive mechanism of sCD25 and HCC serum on Teff responses. The observed sCD25 and HCC serum-mediated suppression is further influenced via novel immune-inhibitory interaction between CD4+CD25+ Treg and sCD25.

Immunotherapy of melanoma by GPI-anchored IL-21 tumour vaccine involves down-regulating regulatory T cells in mouse model

In this study, we developed a tumour cell vaccine expressing a glycosylphosphatidylinositol (GPI)-anchored IL-21 to test the effect of immunotherapy of melanoma in mouse model. The results indicated that the tumour vaccine was functional, exhibiting delayed tumour growth and prolonging longevity of tumour bearing mice. The immunotherapeutic effect was associated with decreasing the numbers of CD4(+) CD25(+) Foxp3(+) Treg (Tregs) cells, increasing IFN-γ level and promoting lymphocyte-infiltration in tumour tissues. Overall, our data demonstrate that the GPI-anchored IL-21 tumour vaccine regulates immune responses at least in part by down-regulating Tregs and reveals enhanced efficacy of tumour vaccine therapy of melanoma.

Families with sleepwalking

BACKGROUND

Studies on families with sleepwalking are uncommonly published but can give further information on the phenotype of patients with chronic sleepwalking.

SUBJECTS AND METHODS

Out of 51 individuals referred for chronic sleepwalking during a 5-year period, we obtained sufficient information on 7 families with direct relatives who reported sleepwalking with or without sleep terrors. Among 70 living direct family members, we obtained questionnaire responses from 50 subjects and identified 34 cases with a history of sleepwalking. Of the 50 subjects, 16 completed only questionnaires, while all the others also completed a clinical evaluation and nocturnal sleep recordings.

RESULTS

There was a positive history of sleepwalking on either the paternal or maternal side of the family over several generations in our 7 families. Thirty-three clinically evaluated subjects had evidence of sleep-disordered breathing (SDB), with associated craniofacial risk factors for SDB (particularly maxillary and/or mandibular deficiencies). There was a complete overlap with the report of parasomnias and the presence of SDB. In cases with current sleepwalking, treatment of SDB coincided with clear improvement of the parasomnia.

CONCLUSION

All of our subjects with parasomnias presented with familial traits considered as risk factors for SDB. These anatomical risk factors are present at birth and even subtle SDB can lead to sleep disruption and instability of NREM sleep. The question raised is: are factors leading to chronic sleep disruption the familial traits responsible for familial sleepwalking?

Formation and reduction of streak artefacts in electron tomography

We have analysed the formation of streak artefacts in the reconstruction based on the filtered back projection algorithm in electron tomography (ET) and accordingly applied an adaptive interpolation technique to artefact reduction. In the adaptive interpolation to recover the missing information, the edge positions in a projection curve were tracked to reduce the interpolation error. A simulation was used to demonstrate the effectiveness of the artefact reduction. Furthermore, image reconstruction of integrated circuit specimens in the ET experiments with the ultra-high voltage electron microscope show that the strong streak artefacts can be reduced effectively by our artefact reduction technique.

Study on genes with altered expression in alpha-amanitin poisoned mice and evaluation on antagonistic effects of traditional Chinese medicines against toxicity of alpha-amanitin

The forward and reverse cDNA subtractive libraries before and after the toxic effect of alpha-amanitin were constructed by suppression subtractive hybridization and randomly selected clones from each subtractive library were screened by PCR and dot blot hybridization. A total of 85 genes with altered expression were finally identified, with 41 genes from the forward library and 44 from the reverse library. Subsequently, the antagonistic effects of candidate traditional Chinese medicines were evaluated based on the genetic transcription levels of the genes with significant altered expression, including Catnbeta, Flt3-L, IL-7r and Rpo2-4. The results indicated that Silybum marianum (L.) Gaert and Ganoderma lucidum had significant down-regulated effects on the transcription level of Catnbeta that was up-regulated by alpha-amanitin, and the two herbs also up-regulated the transcription levels of Flt3-L and Rpo2-4. Silybum marianum (L.) had significant up-regulated effects on the IL-7r that was down-regulated by alpha-amanitin. These preliminary studies suggested that Silybum marianum (L.) and Ganoderma lucidum were effective antagonists against the toxicity of alpha-amanitin.

Identification of tumor stem-like cells in a mouse myeloma cell line

We used colony formation assay in the soft agar media or the serum-free media, the methods of identifying BrdU-label-retaining cells and the SP cells as well as the tumorigenicity test in BALB/c mice, respectively, to analyze tumor stem like cells in the SP2/0 cell line. The results showed that a few SP2/0 cells were capable of forming colonies in the soft agar media, contained BrdU-label-immortal strand in the SP2/0 cell line. The SP2/0 cells in the serum-free media gained higher tumorigenicity in the BALB/c mice than the SP2/0 cells cultivated in the complete media did. Overall, only a few of the SP2/0 cells were found to possess the characteristics of tumor stem-like cells, such as high proliferative potency, more self-renewal and stronger tumorigenesis, or greater similarity to the tumor stem cells (TSCs) traits. The biology of tumor stem-like cells contributes to the identification of molecular targets important for future tumor therapy.

Expression pattern of prmt5 in adult fish and embryos of medaka, Oryzias latipes

DNA methylation is an important biochemical epigenetic determinant of gene expression in cells and therefore actively involved in gene regulation, chromosomal conformation, and protein activity. Protein arginine methyltransferases (PRMTs) play a major role in the methylation of proteins that have an arginine residue, catalyzing both the asymmetric dimethylation of arginine (aDMA) and symmetric dimethylation of arginine (sDMA). PRMT5, a type II PRMT which catalyzes sDMA, has been shown to have a pivotal role in pole plasm assembly and germ cell development in Drosophila and also to be an associate factor of Blimp1 for germ cell development in mouse. Here, we report a homolog of prmt5 identified in medaka, Oryzias latipes, which was detected in the brain, gill, muscle, heart, liver, spleen, intestine, testis and ovary of adult fish by reverse transcriptase-PCR. The expression of prmt5 in the gonads is restricted to oocytes of the ovary, spermatogonia, and spermatocytes of testis. The prmt5 transcripts were detected as early as the one-cell stage and in all the tissues of embryos during embryogenesis. In summary, prmt5 is a maternal determinant factor of embryogenesis of medaka, possibly playing an important role in oogenesis and spermatogenesis in adult medaka.

The role of EGFR MAbs C225 in breast cancer stem cells

e22093

Background: The epithermal growth factor receptor(EGFR) signaling pathways has been implicated in self-renewal of breast cancer stem cells. It has been proved that the EGFR tyrosine kinase inhibitor-gefitinib significantly decreased the mammosphere- forming efficiency(MFE) in ductal carcinoma in situ (DCIS) derived cancer cells. We investigated the response of breast cancer stem cells in breast cancer cell line MCF-7 to EGFR MAbs C225(cetuximab). Methods: Cells were used for nonadherent (i.e.,mammosphere) culture and were divided into four groups according to the different culture medium whether or not including exogenous EGF and MAbs C225. MFE was calculated as the number of mammospheres (≥60um) and was expressed as a percentage. We Compared the percentage of CD44+/CD24- cells from the four groups, and measured the levels of the Wnt and Notch-3 gene expression of the four groups. Results: There was no significant difference of MFE between groups. In the presence of exogenous EGF, MAbs C225 significantly decreased the MFE and the percentage of CD44+/CD24- cells of mammospheres compared with exogenous EGF alone(0.7% versus 1.5%, P < 0.001 and 4% versus 11%P < 0.001;respectively). In the absence of exogenous EGF, MAbs C225 aslo statistically decreased the MFE and the percentage of CD44+/CD24- cells of mammospheres compared with that of lacking exogenous EGF and MAbs C225(0.53% versus 1.3%,P = 0.003 and 9% versus 3%, P < 0.01;respectively). And we observed that the Notch-3 gene expression was compensativly increased in the two groups of addition of MAb C225. No significant differences of Wnt gene expression were observed between groups. Conclusions: EGFR MAbs C225 could disrupt mammoshpere formation and decrease the percentage of CD44+/CD24- cells of mammoshpere cells. The expression of Notch-3 is increased with the EGFR antagonistics in breast cancer stem cells.

No significant financial relationships to disclose.

Screening of medicinal plants from Reunion Island for antimalarial and cytotoxic activity

AIM OF THE STUDY

Nine plants from Reunion Island, selected using ethnopharmacology and chemotaxonomy, were investigated for their potential antimalarial value.

MATERIALS AND METHODS

Thirty-eight extracts were prepared by maceration using CH(2)Cl(2) and MeOH, and were tested for in vitro activity against the 3D7 and W2 strain of Plasmodium falciparum. The most active extracts were then tested for in vitro cytotoxicity on human WI-38 fibroblasts to determine the selectivity index. Those extracts were also investigated in vivo against Plasmodium berghei infected mice.

RESULTS

Most active of the extracts tested were the dichloromethane leaves extracts of Nuxia verticillata Lam. (Buddlejaceae), Psiadia arguta Voigt. (Asteraceae), Lantana camara L. (Verbenaceae), the methanol extracts from Aphloia theiformis (Vahl) Benn. (Aphloiaceae) bark, and Terminalia bentzoe L. (Combretaceae) leaves displaying in vitro IC(50) values ranging from 5.7 to 14.1mug/ml. Extracts from Psiadia, Aphloia at 200mg/(kgday) and Teminalia at 50mg/(kgday) also exhibited significant (p<0.0005) parasite inhibition in mice: 75.5%, 65.6% and 83.5%, respectively.

CONCLUSION

Two plants showed interesting antimalarial activity with good selectivity: Aphloia theiformis and Terminalia bentzoe. Nuxia verticillata still needs to be tested in vivo, with a new batch of plant material.

Estrogen modulates cytokine expression in human periodontal ligament cells

Although systemic bone loss accompanying estrogen deficiency has been proposed as a risk factor for periodontal disease in post-menopausal women, the mechanisms involved remain unclear. The objective of this study was to elucidate the potential bone-sparing effect of estrogen (17beta-estradiol, E(2)) via modulation of inflammatory cytokine production in human periodontal ligament (hPDL) cells. E. coli lipopolysaccharide (LPS) increased the production of pro-inflammatory cytokines TNF-alpha, IL-1beta, IL-6, and receptor activator of NF- B ligand (RANKL) by hPDL cells at both mRNA and protein levels. E(2) treatment reversed the stimulatory effects of LPS on pro-inflammatory cytokine expression by hPDL cells. Moreover, E(2) up-regulated osteoprotegerin (OPG) expression and therefore attenuated the reduction of the OPG vs. RANKL ratio. Our results suggested that estrogen may play a significant role in modulating periodontal tissue responses to LPS, and may exert its bone-sparing effects on periodontal tissues via altering the expression of inflammatory cytokines in hPDL cells.

The expression of estrogen receptors and the effects of estrogen on human periodontal ligament cells

Osteoporotic women exhibit high frequency of alveolar bone loss and low bone density. Estrogen deficiency, which is vital in the pathogenesis of postmenopausal osteoporosis, has received increasing attention in the studies related to the periodontal diseases. Similar to most hormones, estrogen exerts its influence by binding to specific receptors, estrogen receptor (ER)-alpha and -beta. The periodontal ligament cells (PDLcs) are very important in maintaining the integrity of the periodontal tissue, which is the connective tissue located between the alveolar bone and the root surface of tooth. In this study, we evaluated the effects of estrogen deficiency on the alveolar bone in ovariectomized rats by histometric measurement of attachment level in vivo. Using the reverse transcriptase polymerase chain reaction (RT-PCR) and Western-blot procedure, we also detected mRNA and protein products of ERs and investigated the effects of estrogen on bone-forming capability by monitoring alkaline phosphatase (ALP) activity and osteocalcin production in cultured human PDLcs. Our results demonstrated that both ER-alpha and -beta were expressed in PDLcs. Moreover, when exposed to 17-beta estradiol, PDLcs exhibited positive modulation on ALP activity and osteocalcin production. The study suggests that estrogen and ERs may play an important role in periodontal diseases.