IgM specific to lipopolysaccharide of Vibrio cholerae is a surrogate antibody isotype responsible for serum vibriocidal activity

Serum vibriocidal antibody assays have long been used to evaluate the immunogenicity of cholera vaccines formulated with killed whole-cell Vibrio cholerae. However, the antibody isotypes responsible for the serum vibriocidal activity are not fully characterized. In this study, we examined 20 clinical serum samples obtained from human subjects who had been vaccinated with a killed, whole-cell cholera vaccine and a positive control, human convalescent sera with high vibriocidal activity, to determine which isotype antibody is associated with the vibriocidal activity. Antibody isotypes from pooled convalescent sera were fractionated by size-exclusion column chromatography, and the major vibriocidal activity was detected in the IgM fraction. Depletion of IgM antibodies in the convalescent sera produced a significant (P<0.05) decrease in vibriocidal activity (16-fold decrease), whereas only a small change was observed with depletion of IgG or IgA. In addition, anti-LPS IgM antibody showed the highest correlation with vibriocidal activity (Spearman correlation coefficient r = 0.846) among antibody isotypes against heat-killed V. cholerae, lipopolysaccharide (LPS), or major outer membrane protein (Omp U), while total IgG, IgA, or IgM antibody level was not correlated with vibriocidal activity in the 20 human clinical serum samples. Furthermore, human convalescent sera significantly (P<0.001) inhibited the attachment of V. cholerae to HT-29, a human intestinal epithelial cell in vitro. Interestingly, IgM-depleted convalescent sera could not effectively inhibit bacterial adherence compared with non-depleted sera (P<0.05). Finally, bacterial adhesion was significantly inhibited by sera with high vibriocidal titer compared with low-titer sera (P = 0.014). Collectively, we demonstrated that anti-V. cholerae LPS IgM is highly correlated with serum vibriocidal activity and it could be a surrogate antibody isotype representing protective antibodies against V. cholerae.

The relationship between clinical characteristics including presence of exposed lesions and health-related quality of life (HRQoL) in patients with psoriasis: analysis from the nationwide epidemiologic study for psoriasis in Korea (EPI-PSODE study)

BACKGROUND

Psychological aspect and quality of life should be considered in treating patients with psoriasis.

OBJECTIVE

We sought to ascertain which clinical characteristics including presence of exposed lesions are associated with impairment of health-related quality of life (HRQoL) in patients with psoriasis.

METHODS

The EPI-PSODE study was a nationwide, multicenter, cross-sectional study conducted in Korea that included 1260 adult patients with psoriasis. In addition to clinical characteristics including presence of exposed lesions, data were collected using the Psoriatic Arthritis (PsA) Screening and Evaluation (PASE), Dermatology Life Quality Index (DLQI), MOS 36-Item Short-Form Health Survey (SF-36), Work Productivity and Activity Impairment Questionnaire Psoriasis (WPAI: PSO) and Medication Satisfaction Questionnaire (MSQ).

RESULTS

Patients with a DLQI score > 5 (n = 990) were younger, had an earlier onset of psoriasis, scored higher on the Psoriasis Area and Severity Index (PASI), had higher body surface area (BSA) and had higher PASE scores than patients with DLQI ≤ 5 (n = 266). The group of patients with exposed lesions (n = 871) were younger and male predominance, earlier onset of psoriasis, longer disease duration, higher PASI/BSA score and a higher proportion with drinking and smoking history each than the group of patients without exposed lesions (n = 389). Presence of exposed lesions negatively influenced DLQI, 36-Item Short-Form Health Survey (SF-36) (mental component), presenteeism, total work productivity impairment and total activity impairment in the WPAI: PSO. In multiple regression model, PASI score was the only variable which was significantly associated with all HRQoL measures. Presence of exposed lesions was a significant factor affecting DLQI and SF-36 (mental).

CONCLUSION

The presence of exposed lesions has a negative impact on quality of life, mental health and work productivity. Therefore, effective treatments are particularly needed for psoriasis patients with exposed lesions.

Serum bactericidal assay for the evaluation of typhoid vaccine using a semi-automated colony-counting method

Typhoid fever, mainly caused by Salmonella enterica serovar Typhi (S. Typhi), is a life-threatening disease, mostly in developing countries. Enzyme-linked immunosorbent assay (ELISA) is widely used to quantify antibodies against S. Typhi in serum but does not provide information about functional antibody titers. Although the serum bactericidal assay (SBA) using an agar plate is often used to measure functional antibody titers against various bacterial pathogens in clinical specimens, it has rarely been used for typhoid vaccines because it is time-consuming and labor-intensive. In the present study, we established an improved SBA against S. Typhi using a semi-automated colony-counting system with a square agar plate harboring 24 samples. The semi-automated SBA efficiently measured bactericidal titers of sera from individuals immunized with S. Typhi Vi polysaccharide vaccines. The assay specifically responded to S. Typhi Ty2 but not to other irrelevant enteric bacteria including Vibrio cholerae and Shigella flexneri. Baby rabbit complement was more appropriate source for the SBA against S. Typhi than complements from adult rabbit, guinea pig, and human. We also examined the correlation between SBA and ELISA for measuring antibody responses against S. Typhi using pre- and post-vaccination sera from 18 human volunteers. The SBA titer showed a good correlation with anti-Vi IgG quantity in the serum as determined by Spearman correlation coefficient of 0.737 (P < 0.001). Taken together, the semi-automated SBA might be efficient, accurate, sensitive, and specific enough to measure functional antibody titers against S. Typhi in sera from human subjects immunized with typhoid vaccines.

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Improved SBA against S. Typhi was developed using a colony counting system.

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The improved SBA was specific to S. Typhi but not to other gram-negative bacteria.

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There was a good correlation between SBA and anti-Vi IgG titers in vaccinee’s sera.

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This SBA would be useful for the clinical immuno-monitoring of typhoid vaccines.

A Randomized, Placebo-Controlled Trial Evaluating Safety and Immunogenicity of the Killed, Bivalent, Whole-Cell Oral Cholera Vaccine in Ethiopia

Killed whole-cell oral cholera vaccine (OCV) has been a key component of a comprehensive package including water and sanitation measures for recent cholera epidemics. The vaccine, given in a two-dose regimen, has been evaluated in a large number of human volunteers in India, Vietnam, and Bangladesh, where it has demonstrated safety, immunogenicity, and clinical efficacy. We conducted a double-blind randomized placebo-controlled trial in Ethiopia, where we evaluated the safety and immunogenicity of the vaccine in 216 healthy adults and children. OCV was found to be safe and elicited a robust immunological response against Vibrio cholerae O1, with 81% adults and 77% children demonstrating seroconversion 14 days after the second dose of vaccine. This is the first study to evaluate safety and immunogenicity of the vaccine in a population outside Asia using a placebo-controlled, double-blind, randomized study design.

Curcumin inhibits CD4(+) T cell activation, but augments CD69 expression and TGF-β1-mediated generation of regulatory T cells at late phase

BACKGROUND

Curcumin is a promising candidate for a natural medicinal agent to treat chronic inflammatory diseases. Although CD4(+) T cells have been implicated in the pathogenesis of chronic inflammation, whether curcumin directly regulates CD4(+) T cells has not been definitively established. Here, we showed curcumin-mediated regulation of CD2/CD3/CD28-initiated CD4(+) T cell activation in vitro.

METHODOLOGY/PRINCIPAL FINDINGS

Primary human CD4(+) T cells were stimulated with anti-CD2/CD3/CD28 antibody-coated beads as an in vitro surrogate system for antigen presenting cell-T cell interaction and treated with curcumin. We found that curcumin suppresses CD2/CD3/CD28-initiated CD4(+) T cell activation by inhibiting cell proliferation, differentiation and cytokine production. On the other hand, curcumin attenuated the spontaneous decline of CD69 expression and indirectly increased expression of CCR7, L-selectin and Transforming growth factor-β1 (TGF-β1) at the late phase of CD2/CD3/CD28-initiated T cell activation. Curcumin-mediated up-regulation of CD69 at late phase was associated with ERK1/2 signaling. Furthermore, TGF-β1 was involved in curcumin-mediated regulation of T cell activation and late-phase generation of regulatory T cells.

CONCLUSIONS/SIGNIFICANCE

Curcumin not merely blocks, but regulates CD2/CD3/CD28-initiated CD4(+) T cell activation by augmenting CD69, CCR7, L-selectin and TGF-β1 expression followed by regulatory T cell generation. These results suggest that curcumin could directly reduce T cell-dependent inflammatory stress by modulating CD4(+) T cell activation at multiple levels.

Is asymptomatic hemorrhagic transformation really innocuous?

OBJECTIVES

Asymptomatic hemorrhagic transformation (HT) is not associated with immediate deterioration of patients with acute ischemic stroke. However, it is unclear whether it is clinically innocuous with respect to long-term outcome. The aim of this study was to determine the impact of asymptomatic HT on 3-month outcome.

METHODS

A consecutive series of 1,618 patients, hospitalized between January 2004 and August 2007 for ischemic stroke within 7 days from symptom onset were identified in a prospective stroke registry database. Those who had no evidence of acute cerebral ischemia on diffusion-weighted MRI, who did not undergo T2-weighted gradient echo MRI, whose modified Rankin Scale (mRS) score at 3 months after stroke onset was not available, or who had symptomatic HT were excluded. The odds ratio (OR) of asymptomatic HT was calculated for the full distribution of mRS score and adjusted for variables with p < 0.25 with respect to their associations with asymptomatic HT or functional outcome.

RESULTS

Of 1,412 patients eligible for the study, 100 (7.1%) had asymptomatic HT. Patients who experienced asymptomatic HT were more likely to have cardioembolic stroke, to receive thrombolytic therapy, to receive anticoagulation with heparin, and to have a higher initial NIH Stroke Scale score. The crude and adjusted ORs of asymptomatic HT for an increment of mRS score at 3 months were 2.94 (95% confidence interval 2.05-4.24) and 1.90 (1.27-2.82), respectively.

CONCLUSIONS

Our study shows that the odds of a worse outcome are increased by a factor of 2 in patients with asymptomatic HT compared with those without HT after acute ischemic stroke.

Curcumin attenuates decline of CD69 expression on CD4+ T cells and induces generation of CD25hiFoxp3+ T cells through TGF-β1 production (152.22)

Curcumin is a promising candidate as a natural medicinal agent to treat chronic inflammatory diseases. However, little is known about curcumin-mediated CD4+ T cell regulation, which contributes to the therapeutic effects of curcumin. Here, we report that curcumin inhibits T-cell receptor (TCR)-triggered immune responses of CD4+ T cells through suppression of proliferation, cytokine production and differentiation of CD4+ T cells. Intriguingly, spontaneous decline of CD69 expression was attenuated by curcumin treatment, which continued until 6 days of culture. We showed that curcumin-mediated CD69 up-regulation was dependent on extracellular signal-regulated kinase 1/2 (ERK1/2) signaling. Concomitantly, the expressions of C-C motif chemokine receptor 7 (CCR7), L-selectin and transforming growth factor-β1 (TGF-β1) were also increased. TGF-β1 production was moderate, but was high enough to lead to the late generation of CD25hiFoxp3+CD4+ T cells and to maintain prolonged suppression of CD4+ T cell activation. These findings suggest that the immunoregulatory role of curcumin is effective for CD4+ T cells.

Synergistic production of interleukin-23 by dendritic cells derived from cord blood in response to costimulation with LPS and IL-12

This study was performed to provide insight for the optimization and regulation of immune homeostasis, which should be taken into account in the development of cell therapy using DCs and/or cytokine. Human CBDCs costimulated with LPS and IL-12 were examined for cytokine expression compared with ABDCs. Our results showed that costimulation with IL-12 and LPS in CBDCs resulted in increased expression of IL-23. Concomitantly, the phosphorylation of ERKs and p38 MAPK was increased, suggesting that these kinases are important signaling components for IL-23 induction in CBDC costimulated with LPS and IL-12. Furthermore, production of IL-23 in CBDC costimulated with LPS and IL-12 caused CD4(+)CD45RO(+) memory cells to increase IFN-gamma production. Taken together, CBDCs, costimulated with LPS and IL-12, show a synergistic increase in IL-23 production via enhanced phosphorylation of ERK1/2 and p38 MAPK and consequently, an induction of IFN-gamma production in the memory cells.

Immunomodulatory effect of resistin in human dendritic cells stimulated with lipoteichoic acid from Staphylococcus aureus

Resistin is an adipokine whose physiologic role in obesity, type II diabetes mellitus, and inflammatory diseases has been a subject of debate because while it is expressed in adipocytes and adipose tissue in mouse, it is expressed in leukocytes, such as macrophages, in human. In the present study, we attempt to define the effect of resistin on human dendritic cells (DCs) derived from CD14(+) monocytes. When DCs were stimulated with lipoteichoic acid (LTA) and treated with various concentrations of resistin, antigen-uptake process and the endocytic capacity of DCs were decreased. It is intriguing that resistin attenuated cytokine production in LTA-primed DCs. Consequently, T cell activity was reduced when lymphocytes were mixed with Staphylococcus aureus-primed autologous DCs treated with resistin compared to S. aureus-primed DCs without resistin. Our results suggest that resistin interferes with the efficacy of immune responses activated by Gram-positive bacterial infection in human DCs.

Transforming growth factor-beta1 regulates the fate of cultured spinal cord-derived neural progenitor cells

OBJECTIVES

We have evaluated the physiological roles of transforming growth factor-beta1 (TGF-beta1) on differentiation, migration, proliferation and anti-apoptosis characteristics of cultured spinal cord-derived neural progenitor cells.

METHODS

We have used neural progenitor cells that had been isolated and cultured from mouse spinal cord tissue, and we also assessed the relevant reaction mechanisms using an activin-like kinase (ALK)-specific inhibitory system including an inhibitory RNA, and found that it involved potential signalling molecules such as phosphatidylinositol-3-OH kinase (PI3K)/Akt and mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK1/2).

RESULTS AND CONCLUSIONS

Transforming growth factor-beta1-mediated cell population growth was activated after treatment and was also effectively blocked by an ALK41517-synthetic inhibitor (4-(5-benzo(1,3) dioxol-5-yl-4-pyridine-2-yl-1H-imidazole-2-yl) benzamide (SB431542) and ALK siRNA, thereby indicating the involvement of SMAD2 in the TGF-beta1-mediated growth and migration of these neural progenitors cells (NPC). In the present study, TGF-beta1 actively induced NPC migration in vitro. Furthermore, TGF-beta1 demonstrated extreme anti-apoptotic behaviour against hydrogen peroxide-mediated apoptotic cell death. At low dosages, TGF-beta1 enhanced (by approximately 76%) cell survival against hydrogen peroxide treatment via inactivation of caspase-3 and -9. TGF-beta1-treated NPCs down-regulated Bax expression and cytochrome c release; in addition, the cells showed up-regulated Bcl-2 and thioredoxin reductase 1. They also had increased p38, Akt and ERK1/2 phosphorylation, showing the involvement of both the PI3K/Akt and MAPK/ERK1/2 pathways in the neuroprotective effects of TGF-beta1. Interestingly, these effects operate on specific subtypes of cells, including neurones, neural progenitor cells and astrocytes in cultured spinal cord tissue-derived cells. Lesion sites of spinal cord-overexpressing TGF-beta1-mediated prevention of cell death, cell growth and migration enhancement activity have been introduced as a possible new basis for therapeutic strategy in treatment of neurodegenerative disorders, including spinal cord injuries.

OspF directly attenuates the activity of extracellular signal-regulated kinase during invasion by Shigella flexneri in human dendritic cells

Shigella spp., Gram-negative pathogenic bacteria, deliver various effector molecules into the host cell cytoplasm through their type III secretion system to facilitate their invasive process and control the host innate immune responses. Although the function of these effectors is well characterized in epithelial cells during Shigella infection, it has not been elucidated in the dendritic cell (DC), a major antigen presenting cell playing an important role in the initiation of immune responses. In this study, we showed that an invasive Shigella strain (M90T), but not its non-invasive counterpart strain (BS176) induced apoptotic cell death in the human monocyte-derived DCs. Confocal microscopy using a lysosome-associated membrane protein 2 specific antibody demonstrated that the M90T escaped from phagosomes 2h post-DC invasion while BS176 remained in the phagosome. Furthermore, Shigella expressed outer Shigella protein F (OspF), one of the effector proteins that are released through type III secretion system during the invasion, at non-secretion state and further up-regulated OspF expression in the cytoplasm of DC during the invasion. Interestingly, in the host cell, OspF could directly bind to the extracellular signal-regulated kinase (Erk) 1/2 and dephosphorylate phospho-Erk. These results suggest that induction of OspF is enhanced during Shigella invasion of DCs and decreases the phosphorylation level of Erk1/2, which could be at least partially involved in the apoptotic death of DC, eventually resulting in the down-regulation of the host immune response.

Protective effects of PG490-88 on chronic allograft rejection by changing intragraft gene expression profiles

Our previous study showed that PG490-88 effectively ameliorated both functional and histological changes of chronic rejection in the rat. In this experiment, we investigated the intragraft gene expression profiles of PG490-88 under successful prevention of chronic rejection in rat kidney allografts. Kidneys of F344 rats were transplanted into bilaterally nephrectomized LEW recipients. Recipients with a brief course of low-dose FK506 (1 mg/kg per day for 10 days) were dosed with PG490-88 0.5 mg/kg per day, which was predetermined and defined as the effective dose of preventing chronic allograft rejection in this model, for 90 days after grafting. Kidney grafts were harvested on day 90 after transplantation and subjected to gene expression analysis by real-time RT-PCR. Overall, the expression levels of all genes tested were upregulated in the brief course of low-dose FK506 control. PG490-88 treatment exhibited significant inhibition of intragraft m RNA levels of iNOS, IL-6, and perforin and marginal downregulation of IL-2, IFNgamma, IRF-1, TNFalpha, and TGFbeta. There was no change in IL-10, granzyme B, and PDGFalpha, when compared to the brief course of low-dose FK506 control. These results suggested that downregulation of multiple intragraft gene expression by mainly suppression of iNOS, IL-6, and perforin might be responsible for successful prevention of chronic kidney allograft nephropathy by PG490-88 in rats.

PG490-88, a new immunosuppressant, effectively prevents acute and chronic rejection in rat renal allografts

PG490-88 is a semisynthetic derivative of the novel compound PG490 (triptolide) purified from a Chinese herb. It has been shown to prolong acute allograft survival in multiple experimental organ transplant models. However, the effect of PG490-88 on prevention of acute and chronic renal allograft rejection has not been determined. Kidneys of ACI or F344 rats were transplanted into bilaterally nephrectomized LEW recipients as the acute or chronic allograft rejection models, respectively. Treatment of LEW recipients with PG490-88 significantly prolonged ACI kidney graft survival in a dose-dependent manner when compared with the untreated allograft controls. LEW recipients of F344 kidney grafts who received PG490-88 for 90 days with a brief course of low-dose FK506 showed normal serum creatinine levels and markedly reduced histological changes of chronic rejection at day 90 after transplantation. These results suggest that PG490-88 significantly prolongs kidney allograft survival in an acute rejection model and prevents chronic allograft rejection in rats.

Treatment of landfill leachate by a pilot-scale modified Ludzack-Ettinger and sulfur-utilizing denitrification process

Nitrogen removal efficiency of a pilot-scale system consisted of Modified Ludzack-Ettinger (MLE) followed by sulfur-utilizing denitrification (SUDNR) process was evaluated with a landfill leachate. For SUDNR, a down-flow mode sulfur packed bed reactor (SPBR) filled with sulfur and limestone particles was used. Although total nitrogen removal efficiency of the MLE process was about 80% at the recycle ratio of 4, effluent contained 350-450 mg/L NO(3-)-N. Up to a loading rate of 1.2 kg NO(3-)-N/m3-day, the SPBR could achieve complete removal of nitrate, and nitrate removal rate was kept to that level even at higher loading rate. When a COD/N ratio of MLE process was maintained at 2 instead of 4, more organics with molecular weight less than 500 were utilized for heterotrophic denitrification although denitrification was not complete with the lack of electron donors. Clogging in the SPBR, mainly by the accumulation of nitrogen gas in the pores, could easily be removed by introducing the effluent in an upward direction for 1 min at 1 hr intervals. The proposed treatment system could achieve nitrate free effluent with a slight increase in chemical cost. Furthermore, depending on further COD removal requirement after biological treatment, the proposed treatment system can be an economical solution.

Clinicopathological and genotypic aspects of anticonvulsant-induced pseudolymphoma syndrome

BACKGROUND

Pseudolymphoma syndrome (PLS) is relatively rare but can lead to death if there are extensive skin lesions, severe hepatitis, agranulocytosis and neutropenia. PLS may also give rise to harmful effects if misdiagnosed as malignant lymphoma and patients with PLS are treated unnecessarily with chemotherapy, because it may mimic histologically other lymphomas, including mycosis fungoides (MF).

OBJECTIVES

To examine the clinicopathological and genotypic features of anticonvulsant-induced PLS. Patients and methods We retrospectively reviewed clinical, laboratory and histological findings for eight cases of anticonvulsant-induced PLS, and performed T-cell receptor gene rearrangement using polymerase chain reaction with paraffin-embedded specimens from each case.

RESULTS

The causative agents were carbamazepine (four cases), phenytoin (two cases), phenobarbital (one case) and valproic acid (one case). A cross-reaction between phenobarbital and phenytoin was observed in one case. The duration from the start of anticonvulsant therapy to skin eruption was 3-24 weeks (mean 7 weeks). The skin lesions were generalized maculopapular eruptions in all cases, including one case accompanied by vesiculopustular lesions. The frequencies of the associated features were as follows: facial oedema (88%), fever (75%), lymphadenopathy (63%), and hepatomegaly (25%). Laboratory findings revealed leukocytosis, atypical lymphocytes, eosinophilia, monocytosis, neutrophilia, lymphocytosis and abnormal liver function. Histopathologically, there was similarity between PLS and MF in that epidermotrophism of atypical lymphocytes (100%) and Pautrier's microabscess-like structures (38%) were observed. However, PLS has some differences from MF that include moderate to marked spongiosis (75%), necrotic keratinocytes (63%), and infiltration of eosinophils (25%) in the epidermis and, in the dermis, papillary dermal oedema (100%), extravasated erythrocytes (100%), lymphocytes within the dermis larger than those within the epidermis (63%), and infiltration of various inflammatory cells including neutrophils (50%). Genotypic analysis demonstrated a rearrangement of the T-cell receptor-gamma gene in one of eight cases studied. There were no deaths and all cases were improved at 2-9 weeks (mean 6 weeks), after the cessation of causative agents, systemic and topical corticosteroid therapy, and symptomatic therapy. There were no significant differences in clinical, laboratory and histological findings between the causative agents.

CONCLUSIONS

PLS may show histopathological findings similar to MF and take a prolonged course even after the cessation of causative agents. Thus, a clear understanding and diagnosis of this disease is considered to have an important effect on treatment and prognosis.

Mycosis fungoides presenting as Ofuji's papuloerythroderma

We report three patients presented with clinical features of Ofuji's papuloerythroderma (pruritic erythematous papules and extensive erythema sparing all skin folds), however, showing histopathological findings of mycosis fungoides (Pautrier's microabscess, haloed lymphocytes, disproportionate epidermotropism, and wiry collagen bundles). One case was associated with plaque stage of mycosis fungoides and follicular mucinosis. T-cell receptor (TCR) gene rearrangement analysis in the lesional skin tissue demonstrated rearrangement of the gamma chain in all cases. HTLV-1 serology was negative for two patients who conducted HTLV-1 test. We think that Ofuji's papuloerythroderma might be a variant of early mycosis fungoides rather than secondary skin manifestations to certain cutaneous inflammatory diseases.

Narrowbore high-performance liquid chromatography for the simultaneous determination of sildenafil and its metabolite UK-103,320 in human plasma using column switching

A fully automated narrowbore high-performance liquid chromatography method with column switching was developed for the simultaneous determination of sildenafil and its active metabolite UK-103,320 in human plasma samples without pre-purification. Diluted plasma sample (100 microl) was directly introduced onto a Capcell Pak MF Ph-1 column (20x4 mm I.D.) where primary separation occurred to remove proteins and concentrate target substances using 15% acetonitrile in 20 mM phosphate solution (pH 7). The drug molecules eluted from the MF Ph-1 column were focused in an intermediate column (35x2 mm I.D.) by a valve switching step. The substances enriched in the intermediate column were eluted and separated on a phenyl-hexyl column (100x2 mm I.D.) using 36% acetonitrile in 10 mM phosphate solution (pH 4.5) when the valve status was switched back. The method showed excellent sensitivity (detection limit of 10 ng/ml), good precision (RSD < or = 2.3%) and accuracy (bias: +/-2.0%) and speed (total analysis time 17 min). The response was linear (r2 > or = 0.999) over the concentration range 10-1000 ng/ml.

Cryopreservation of Taxus chinensis suspension cell cultures

A simple cryopreservation method for suspension cells of Taxus chinensis was established. In this procedure 7 days old suspension cells were used without any pre-culture treatment. At first, cells were incubated in cryoprotectant solution (0.5M DMSO and 0.5M glycerol) on ice for 30 min and then frozen at a cooling rate of 1 degree C/min to -40 degrees C prior to immersion in liquid nitrogen. The average viability of frozen-thawed cells was between 30 to 40%. The recovery of cryopreserved cells in liquid nitrogen for 1 month was accomplished. After rapid thawing, cells were transferred to solid medium and cultivated for 4-6 weeks. The treatment of trehalose as a cryoprotectant enhanced re-growth of frozen-thawed cells. The stable maintenance of paclitaxel biosynthetic ability in cryopreserved cells was confirmed by comparing with that of regularly sub-cultured suspension cells.

Notch signaling as a target in multimodality cancer therapy

Notch signaling is an extremely conserved and widely used mechanism controlling cell fate determination. Recent evidence shows that Notch receptors regulate cell differentiation, proliferation and apoptosis in many cells, including neoplastic cells. In the context of cancer experimental immunotherapy and multimodality therapy, the Notch signaling network is acquiring increasing importance for its possible roles in both neoplastic cells and the immune system. In this review, we discuss: (i) the roles of Notch signaling in cancer cells and the immune system; and (ii) strategies through which Notch-targeting biologicals may be used to increase the effectiveness of multimodality cancer treatment, including cancer vaccines.

Evaluation of selected lichens from iceland for cancer chemopreventive and cytotoxic activity

Cancer chemopreventive effects of organic extracts from 29 species of lichens collected in Iceland were evaluated using a panel of in vitro bioassays whereby extracts were tested for potential to induce quinone reductase (QR) and differentiation of human promyelocytic leukemia (HL-60) cells, inhibit cyclooxygenase-1 (COX-1), phorbol ester-induced ornithine decarboxylase (ODC), aromatase and sulfatase, as well as for antioxidant, estrogenic/anti-estrogenic and antiproliferative activity. In addition, the extracts were tested for cytotoxicity against 12 cancer cell lines. The most significant results were exhibited by extracts from Xanthoria elegans and Alectoria nigricans , which respectively, induced QR activity (concentration to double activity = 4.8 µg/ml) and inhibited phorbol ester-induced ODC activity with mouse 308 cells in culture (IC 50 = 2.6 µg/ml). Moderate inhibition of [ 3 H]thymidine incorporation with HL-60 cells was exhibited by the Peltigera leucophlebia extract. Several extracts prevented estrogen formation from estrogen precursors by inhibiting the enzymatic activities of aromatase ( Sphaerophorus globosus , Cetrariella delisei , Melanelia hepatizon ) and sulfatase ( Cladonia gracilis , Sphaerophorus fragilis , S. globosus ). None of the extracts demonstrated significant cytotoxic effects with selected cell lines.

Epithelioid leiomyosarcoma of the skin

We report a case of epithelioid leiomyosarcoma that developed on the nose of a 55-year-old Korean male over a one year period. The lesion was a pea sized, firm, erythematous, painless nodule with erosion in the center. Histologic examination revealed short spindled cells with blunt-ended nuclei and pleomorphic round to oval epithelioid cells with abundant eosinophilic cytoplasm that were perivascular and densely packed in the dermis. Immunostaining for desmin was negative, although stains for vimentin and smooth muscle actin were both strongly positive.