bluuebunny/crossref_metadata_2025 huggingface dataset:
Suppression of Specific IgE Antibody Responses by Liposome-Conjugated Ovalbumin in Mice Sensitized with Ovalbumin via the Respiratory Tract
Authors: Yoshikawa Tomoki , Uchida Tetsuya , Naito Seishiro , Horino Atsuko , Taneichi Maiko , Kato Hiroshi , Komuro Katsutoshi , Nakano Yoshio , Mori Masahito , Nishinohara Shouichi , Chiba Joe , Kurata Takeshi , Tamura Shin-ichi
Published: April 2003

Background: Previously we have shown that intranasal administration of ovalbumin (OVA) together with cholera toxin (CT) abrogates nasal tolerance to OVA, resulting in the induction of specific IgE antibody (Ab) responses, and that intraperitoneal injection of OVA coupled with liposomes (OVA-liposomes) induces a selective suppression of IgE Ab responses to OVA. Whether OVA-liposomes suppress anti-OVA IgE Ab responses in mice sensitized with CT-combined OVA via the respiratory tract remains to be clarified. Methods: In some experiments, mice were given OVA, liposomes or OVA-liposomes with or without CT intranasally three times, at 2-week intervals (weeks 0, 2 and 4). In other experiments, mice were given OVA-liposomes intranasally 2 days before or 1 and 3 weeks after CT-combined OVA (week 0), which was administered intranasally three times, at 2-week intervals (weeks 0, 2 and 4). Two weeks after the third administration of CT-combined OVA (week 0), nasal wash and serum IgA, IgG and IgE Ab responses were assayed. Results: Pretreatment with OVA-liposomes suppressed IgE Ab responses to CT-combined OVA, with a significantly high production of both nasal IgA and serum IgG Abs. Moreover, treatment with OVA-liposomes 1 and 3 weeks after CT-combined OVA administration also suppressed IgE Ab responses. The suppression of anti-OVA IgE Ab production by OVA-liposomes was accompanied by a simultaneous enhancement of specific IgA and IgG (IgG1, and especially IgG2a) Ab production. Conclusions: Postimmunization treatment with OVA-liposomes, as well as preimmunization treatment, suppressed specific IgE Ab responses in mice sensitized intranasally with CT-combined OVA. Allergens conjugated to liposomes may be appropriate for preventing the development of allergies to inhaled or dietary antigens in humans.
Specific IgE Levels to Cicer arietinum (Chick Pea) in Tolerant and Nontolerant Children: Evaluation of Boiled and Raw Extracts
Authors: Martínez San Ireneo Mercedes , Ibáñez Sandín Maria Dolores , Fernández-Caldas Enrique , Marañón Lizana Francisco , Rosales Fletes Maria José , Laso Borrego Maria Teresa
Published: April 2003

The chick pea, Cicer arietinum, is a legume commonly consumed in Spain and other Mediterranean countries. The sera of 29 children (mean age: 8.4 years) with a current or past history of allergic reactions after ingestion of chick pea, and positive skin tests to this legume, were used to study the allergenic composition of raw and boiled chick pea extracts. The patient population was divided into 2 groups: group 1 consisted of 19 patients with clinical sensitivity confirmed by either positive oral challenges or a convincing recent history of anaphylaxis after eating chick peas, and group 2 consisted of 10 patients with clinical sensitivity in the past, but tolerant at the time of blood extraction. Six atopic children, not allergic to legumes, were included as controls. Specific IgE to the raw and boiled extracts was measured by ELISA. The allergenic composition of both extracts was analyzed by SDS-PAGE and immunoblots. There were no significant differences between specific IgE levels to the raw and boiled extracts (p = 0.23). The mean levels in group 1 were significantly higher than in group 2 and controls (p = 0.0001). Multiple IgE binding proteins/peptides were detected in both extracts in the molecular weight range of 10–106 kD. Only nontolerant patients recognized a similar number of bands in both extracts. Chick pea extracts contain a majority of heat-stable allergens, which could be responsible for the clinical sensitivity to chick pea. Patients with a current clinical allergy to chick pea have statistically higher specific IgE levels than tolerant patients and controls.
Beclomethasone Decreases Elevations in Phosphodiesterase Activity in Human T Lymphocytes
Authors: Crocker I. Caroline , Church Martin K. , Ohia S. Edet , Townley Robert G.
Published: April 2003

Background: We recently reported that CD4+ T cells that have been activated in vivo or in vitro contain elevated cyclic adenosine monophosphate (cAMP) phosphodiesterase (PDE) activity. Since both phosphodiesterase inhibitors and glucocorticoids have anti-inflammatory activity, we sought to investigate the effect of beclomethasone on PDE activity. Methods: PDE activity was measured in CD4+ T cells after 24 h of culture with beclomethasone. Cells were obtained from the peripheral blood of nonatopic persons (nCells), pre-seasonal (pCells), seasonal (within the first 2 weeks; sCells) and mid-seasonal (mCells) allergic rhinitics and asymptomatic allergic asthmatics (aCells). In addition, the effect of beclomethasone on Th2 cell lines and cells that had been activated in vitro with PHA or interleukin (IL)-2 was determined. Results: PDE activity was decreased in a concentration-dependent manner by incubation of mCells, Th2 lines and PHA or IL-2-activated CD4+ T cells with beclomethasone (p < 0.05). However, beclomethasone did not modulate PDE activity in nCells, pCells, sCells, or aCells. Conclusions: Beclomethasone only decreases cAMP PDE activity in CD4+ T cells when it is increased by cell activation either in vitro or in vivo.
Cutaneous CD30+ Cells in Children with Atopic Dermatitis
Authors: Cavagni Giovanni , Caffarelli Carlo , Facchetti Fabio , Brugnoni Duilio , Notarangelo Luigi D. , Tosoni Cinzia , Altobelli Roberto
Published: April 2003

Background: CD30 expression can be considered a marker of Th2 cells. We investigated the presence of CD30+ cells in the lesional skin of children with atopic dermatitis (AD). We also analyzed the possible relationship between CD30+ cells and serum soluble CD 30 (sCD30) levels, and IgE, soluble interleukin-2 (IL-2) receptor (sIL-2R) or soluble CD23 (sCD23) levels in the blood, and clinical score. Methods: Ten eczematous children (4 males, 6 females; median age: 4 years and 5 months; range: 11 months to 14 years), 9 sex- and age-matched control children and an adult control group were studied. A clinical score (SCORAD index), was given to eczematous lesions. Blood was taken for the determination of IgE, sCD30, sIL-2R and sCD23 levels. Punch biopsies of lesional skin were stained with hematoxylin and eosin or incubated with anti-CD30 monoclonal antibodies. Skin prick tests (SPTs) were also performed. Results: In the biopsy specimens, CD30 expression was observed in high proportions of infiltrating cells. In children with AD, total serum IgE, sCD30, sIL-2R, sCD23 and eosinophils were significantly elevated compared to controls. CD30+ cells were not associated with serum IgE, sCD30, sIL-2R, sCD23, or SPT results, score of inflammatory cells in lesional skin or clinical score. Children with AD who had high total IgE and specific IgE antibodies did not differ from those with normal total IgE and negative specific IgE in respect of age, clinical score, number of CD30+ cells, sCD30, sIL-2R and sCD23 levels, score of inflammatory cells in skin or clinical score. Conclusion: Our results showed remarkable numbers of CD30+ cells in the lesional skin and high sCD30 in the serum of children with AD. CD30+ cells did not correlate with systemic markers of IgE reaction.
HIV-1 gp41 by N-Domain Binds the Potential Receptor Protein P45
Authors: Xiao Yi , Wu Weicheng , Dierich Manfred P. , Chen Ying-Hua
Published: April 2003

Recent crystal structure analysis of HIV-1 gp41 revealed that two domains (N- and C-domains) on gp41 play an important role in mediating membrane fusion and HIV-1 entry. The experimental evidence that gp41 by N-domain bound the potential receptor protein P45 could help to understand the mechanism of HIV entry. A recombinant soluble gp41 (rsgp41: Env aa539–684) could bind to P45 in the affinity capillary electrophoresis analysis and the surface plasmon resonance assay. In a blockade assay, peptide P1 (Env aa583–599) could inhibit interaction between rsgp41 and P45, while a control peptide could not. Direct binding of rsgp41, rgp41DP (aa567–648), P1 peptide and (P1)2 peptide [(aa586–596)2] to P45 was examined in an ELISA assay. Rsgp41 bound the potential receptor protein P45 strongly, while rgp41DP and P1 as well as (P1)2 could all weakly bind to P45, indicating that gp41 by N-domain weakly binds P45 and the region RILAVERYLKD located in the N-domain is defined as the binding site for P45 binding.
Skin Prick Test Reactivity to Recombinant Latex Allergens
Authors: Yip Lisa , Hickey Vicky , Wagner Birgit , Liss Gary , Slater Jay , Breiteneder Heimo , Sussman Gordon , Beezhold Donald
Published: April 2003

Background: Allergy to latex has become a serious and increasingly common health problem, particularly for healthcare workers and patients who undergo frequent surgical procedures. Testing for latex allergy currently involves in vitro tests and skin prick testing using crude preparations of natural rubber latex (NRL). To date, 10 latex proteins have received designation as allergens (Hev b 1 to Hev b 10) and, except for Hev b 4, have been cloned as recombinant proteins. Our aim was to compare the skin prick test (SPT) reactivity of six recombinant latex allergens with SPT reactivity to natural rubber latex proteins in known latex-allergic individuals. Methods: Six recombinant proteins were expressed in Escherichia coli, and tested as the intact fusion proteins (Hev b 2, 5, 6, 8) or as purified proteins (Hev b 3 and 7). SPT with the six recombinant latex allergens was performed using 10-fold serial dilutions on 31 latex-allergic subjects to determine the level of reactivity to each recombinant allergen. Latex-specific IgE was determined using the AlaSTAT assay. Results: All six recombinant allergens were reactive by SPT in at least 1 latex-allergic patient but not in any of the control patients. The frequency of sensitization to the various recombinant allergens was similar to previous studies using the native proteins isolated from NRL. The minimal level of protein for a positive skin test was 70 pg/ml for NRL and 1 ng/ml for one recombinant allergen (Hev b 7). In our patients, the use of a combination of recombinant latex allergens Hev b 5, 6 and 7 diagnosed latex allergy with 93% sensitivity and 100% specificity. Conclusion: Recombinant latex allergens are clinically reactive, can be produced in a standardized manner, and could potentially provide safe, sensitive and specific reagents for the diagnosis of latex allergy.
Plant Allergens and Pathogenesis-Related Proteins
Authors: Hoffmann-Sommergruber Karin
Published: April 2003

In the recent past a great number of proteins causing type 1 allergic reactions in humans have been isolated and characterised. The main sources containing allergens are plants, mites, fungal spores and insects. Plant-derived allergens may either be taken in from the upper respiratory tract or they are present in a vast range of plant food causing food allergic reactions. Compared to the enormous amount of different plant proteins only a small number out of them are identified as a an allergen at present. Looking at the allergen encoding sequences, relationships by sequence similarity can be found quite frequently to a restricted number of plant protein families. Predominantly, these protein families are seed storage proteins, structural proteins and proteins involved in the defence-related system – pathogenesis-related proteins. In the following, a short overview of a number of pathogenesis-related protein families is presented in relation to the already known homologous plant allergens.
Peptide-Mediated Immune Responses in Specific Immunotherapy
Authors: Haselden Brigitte M. , Kay A. Barry , Larché Mark
Published: April 2003

Conventional immunotherapy using whole allergen extracts has been shown to be an effective, disease-modifying treatment in carefully selected patients with allergic conjunctivo-rhinitis, asthma and bee and wasp venom hypersensitivity. However, this form of therapy is associated with the risk of systemic anaphylaxis, which, when severe, can be life threatening. A potentially significant reduction in the incidence of IgE-mediated events during immunotherapy may be achieved by the use of short peptides corresponding to T cell epitopes which, by virtue of their size, are incapable of cross-linking allergen-specific IgE bound to the surface of mast cells and basophils. Initial clinical studies have demonstrated degrees of efficacy which have, in some cases, been associated with adverse events occurring immediately or several hours after peptide administration. Preliminary data from studies employing shorter peptides (20 amino acids or less) suggest that improved efficacy may be achieved by using peptides of defined major histocompatibility complex-binding specificity administered in an incremental dose fashion comparable to conventional immunotherapy. This review will discuss the concept of peptide immunotherapy and the implications of recent studies.
Induction of High Levels of Antibodies Recognizing the Neutralizing Epitope ELDKWA and the D- or K-Position-Mutated Epitopes by Candidate Epitope Vaccines against HIV-1
Authors: Xiao Yi , Dong Xiao-Nan , Chen Ying-Hua
Published: April 2003

Monoclonal antibody 2F5 recognizing the ELDKWA epitope on HIV-1 gp41 has a significant neutralization potency against 90% of the investigated viruses of African, Asian, American, and European strains, but the antibody responses to the epitope 2F5 in HIV-1-infected individuals were very low. We attempted to induce high levels of epitope-specific antibodies to ELDKWA and its three mutated epitopes by candidate epitope vaccines. The four candidate epitope vaccines all induced strong antibody responses at dilutions from about 1:6,400 to 1:25,600. We tested the cross-reactions between these antisera and four epitope peptides. The ELDKWA-specific antisera showed strong cross-reactivity with three neutralizing-resistant mutated epitopes which contain changes in the D or K positions of the epitope sequence. Virus variants containing these changes could escape neutralization by monoclonal antibody 2F5. In immunoblotting analysis, the ELDKWA, ELDEWA, and ELEKWA epitope specific antibodies all recognized rsgp41 which confirms that the antibodies against both mutated epitopes, ELDEWA and ELEKWA, could cross-react with the native epitope on rsgp41. Although it is not clear whether the polyclonal antibodies induced by the ELDKWA epitope vaccine could neutralize the mutated viruses containing these mutated epitopes, it is conceivable that epitope vaccines based on mutated epitopes could induce strong antibody responses with predefined epitope specificity to neutralize mutated viruse containing the mutated epitope. An epitope vaccine, using different epitopes including mutated epitopes, could provide a new concept for developing a new vaccine against HIV-1.
Editorial Overview: Antinuclear Antibody- and Extractable Nuclear Antigen-Related Diseases
Authors: Hiepe Falk , Dörner Thomas , Burmester Gerd-Rüdiger
Published: April 2003

In 1948, the observation of the LE cell phenomenon in a patient with systemic lupus erythematosus (SLE) began the discovery of a broad variety of autoantibodies directed to nuclear antigens called antinuclear antibodies (ANA). Nowadays, different ANA serve as important diagnostic parameters for differentiating most of the connective tissue diseases, such as SLE, neonatal lupus syndromes, Sjögren’s syndrome, scleroderma, autoimmune myositis, mixed connective tissue disease and other overlaps. This overview summarizes the history of ANA and their detection methods, in part to introduce the subsequent papers dealing with special topics of ANA-related diseases in this issue. Furthermore, the pathogenic role of these autoantibodies in targeting non-organ-specific intracellular antigens as a functional important constituent of a subcellular particle or multimolecular complex is addressed. Notably, some of these autoantibodies have functioned as significant tools for cell biologists to elucidate the subcellular structures and functions of these autoantigens. In the future, we can expect further advances to answer such important questions as why these antigens are targets of autoantibodies, what is their pathogenic impact and what are the triggers of autoimmunity?
Molecular Cloning of Paramyosin, a New Allergen of Anisakis simplex
Authors: Pérez-Pérez Julián , Fernández-Caldas Enrique , Marañón Francisco , Sastre Joaquín , Bernal Magdalena Lluch , Rodríguez Julia , Bedate Carlos Alonso
Published: April 2003

Background: Anisakis simplex is a fish parasite that, when accidentally ingested by humans, may cause allergic reactions in sensitized individuals. The main objectives of our study were to: (1) construct a cDNA expression library of A. simplex; (2) identify clones producing specific IgE binding protein antigens, and (3) produce and purify the protein/s codified by the isolated clones produced in Escherichia coli. Methods: An expression cDNA library from the third stage larvae (L3) of A. simplex was constructed. This library was first screened with a rabbit anti A. simplex hyperimmune serum. The positive clones, identified using the rabbit serum, were rescreened with a pool of human sera containing high titers of IgE antibodies against A. simplex. Results: Two positive clones were isolated carrying the genes which codify for paramyosin. The paramyosin protein was produced in E. coli and purified. The partial sequence of a second paramyosin gene was also identified. The frequency of specific IgE binding to the recombinant and native forms of paramyosin using the sera of 26 A. simplex-sensitive individuals was 23 and 88%, respectively. Both paramyosins were able to inhibit 11% of the specific IgE binding to a total extract. Conclusions: We describe the primary structure of a paramyosin of A. simplex. It can be considered as an allergen based on its IgE binding capacity. We suggest that the recombinant protein does not maintain the complete allergenic properties of the native paramyosin, considering its lower IgE binding capacity of the recombinant protein. However, both proteins have the same specific IgE inhibition capacity. The recombinant protein can be produced in large quantities in E. coli. We propose the term Ani s 2 for this allergen.
A Soybean G2 Glycinin Allergen
Authors: Helm Ricki M. , Cockrell Gael , Connaughton Cathie , Sampson Hugh A. , Bannon Gary A. , Beilinson Vadim , Nielsen Niels C. , Burks A. Wesley
Published: April 2003

Background: Multiple allergens have been documented in soybean extracts. IgE from individuals allergic to soybeans, but not to peanut, has been shown by immunoblot analysis to bind to proteins with a molecular weight of approximately 22 kD. These findings suggested that this unique protein fraction from soybean might be responsible, in part, for soybean allergic reactivity. The objective of the present study was to characterize specific B cell epitopes, to determine if any amino acid was critical to IgE binding and to model the 22-kD G2 soybean allergen to the three-dimensional (3-D) phaseolin molecule. Methods: B cell epitopes were identified using SPOTs peptide analysis. Structural orientation of the IgE-binding regions was mapped to the 3-D phaseolin molecule using molecular modeling of the protein tertiary structure. Results: Eleven linear epitopes, representing 15 amino acid peptide sequences, bound to IgE in the glycinin molecule. These epitopes were predicted to be distributed asymmetrically on the surface of G2 trimers. Conclusions: Only 1 epitope could be rendered non-IgE binding by alanine substitutions in the peptide. The nonrandom distribution of the IgE binding sites provides new insight into their organization in trimers in 11S complexes of the G2 glycinin allergen.
Development of a Monoclonal Antibody-Based Sandwich ELISA for Detection of the Latex Allergen Hev b 1
Authors: Raulf-Heimsoth Monika , Sander Ingrid , Chen Zhiping , Borowitzki Gerda , Diewald Kai , van Kampen Vera , Baur Xaver
Published: April 2003

Background: Natural rubber latex (NRL) products are complex mixtures consisting of different allergenic components. Among them, Hev b 1 belongs to the important and well-characterized ones. To quantify the relevant allergen Hev b 1 in NRL products, a two-site monoclonal antibody (mAb)-based assay was developed. Methods: Two Hev b 1-specific mAbs with different epitope recognition and ability to bind simultaneously to an Hev b 1 molecule were used in the study. Both mAbs (II4F9 and II4G9) were enriched by in vitro production in a modular minifermenter and affinity purified. Wells of micro-ELISA plates coated with captured mAb II4G9 were incubated with samples containing Hev b 1. Bound Hev b 1 was detected by a combination of biotinylated mAb II4F9 as detection antibody and peroxidase-labeled avidin. Results: The optimized sandwich ELISA was highly reproducible in the linear range of the standard curve and Hev b 1 concentrations ranging from 12.5 to 400 ng/100 μl could be detected. The assay was suitable for the detection of Hev b 1 concentrations in latex sap and latex products, e.g. gloves, with a detection limit of 1.25 μg of Hev b 1/g of rubber. In a preliminary study with five different brands of latex gloves, Hev b 1 concentrations were found to be in the range of 18–40 μg per gram of rubber material, corresponding to 2–4% of the total extractable protein content in latex glove extracts. Conclusions: A sensitive sandwich assay was developed to quantify the latex allergen Hev b 1. This assay can be used to standardize latex extracts with regard to the content of the major allergen Hev b 1.
Expression of N-Acetyl Galactosaminylated and Sialylated Glycans by Metastases Arising from Primary Breast Cancer
Authors: Brooks Susan A. , Leathem Anthony J. C.
Published: April 2003

This study examines the Helix pomatia lectin (HPA) binding characteristics of metastases arising from primary breast cancer, and compares HPA binding patterns with binding of Dolichos biflorus lectin (DBA), Limax flavus lectin (LFA), and a monoclonal antibody against the Tn epitope. Of 81 blocks of metastases in a range of tissues, taken at autopsy from 46 individuals, 79% were HPA positive. No site specificity with regard to HPA binding was observed. Both HPA-positive and -negative tumour deposits were seen within a single individual. HPA-positive tumours were commonly negative for binding of sialic acid specific lectin LFA (86% were negative). Binding patterns of α-GalNAc specific HPA and DBA, and a monoclonal antibody against Tn epitope (GalNAc-O-Ser/Thr) were markedly different.
Increased Tumorigenicity and Invasiveness of C6 Rat Glioma Cells Transfected with the Human {FC12}a-2,8 Sialyltransferase cDNA
Authors: Sottocornola E. , Colombo I. , Vergani V. , Taraboletti G. , Berra B.
Published: April 2003

Gangliosides are thought to be involved in tumor cell proliferation, migration and invasiveness as so far demonstrated by the addition of exogenous gangliosides to the culture medium. To better understand the direct influence that alterations in ganglioside synthesis can exert on these functional aspects of cell biology, in the present study, we investigated the behaviour of C6 rat glioma cells after stable transfection with the human CMP-NeuAc:NeuAcα2-3Galβ1-4GlcCer α2,8-sialyltransferase (SAT-II, EC 2.4.99.8) gene. The enzyme synthesizes ganglioside GD3 by adding a sialic acid residue to ganglioside GM3. Stable transfection of the constructs into C6 cells and expression of the human SAT-II gene were evaluated using PCR and RT-PCR amplification, respectively. Qualitative and quantitative analysis of the ganglioside profile was performed by conventional HP-TLC and identity of de novo synthesized species was assessed by TLC immunostaining. Results show that whereas C6 parental cells and C6 cells transfected with the empty expression vector synthesize, almost exclusively, ganglioside GM3, de novo synthesis of GD3 is clearly observed in clones expressing the α2,8-sialyltransferase. Subcutaneous grafting in athymic nude mice of cells expressing high levels of GD3 induces tumors growing faster and more aggressively than controls. In in vitro assays, the same cells demonstrate increased proliferation rate, motility and invasiveness. Chemotaxis and chemoinvasion were assayed using the modified Boyden chamber. Data obtained suggest that endogenously neosynthesized GD3 is able to modify proliferation rate, motility and invasion of C6 rat glioma cells, enhancing the features of malignancy of this tumor cell line.
Effects of EGF and TGF-α on Invasion and Proteinase Expression of Uterine Cervical Adenocarcinoma OMC-4 Cells
Authors: Ueda Masatsugu , Fujii Hideji , Yoshizawa Keiko , Terai Yoshito , Kumagai Koji , Ueki Ken , Ueki Minoru
Published: April 2003

Uterine cervical adenocarcinoma typically is an aggressive neoplasm with a propensity for early invasion and dissemination; however, the regulatory mechanism of invasive activity of cervical adenocarcinoma cells has not been fully understood. In this study, biological effects of epidermal growth factor (EGF) and transforming growth factor (TGF)-α on invasion and proteinase expression of human cervical adenocarcinoma OMC-4 cells were investigated. Tumor cell migration along a gradient of substratum-bound fibronectin and invasion into the reconstituted basement membrane were stimulated by 0.1–10 nM EGF and TGF-α in a concentration-dependent manner. Their effects on tumor cell migration were also confirmed by wound assay. The zymography of tumor-conditioned medium showed that the treatment of OMC-4 cells with EGF and TGF-α resulted in the increase of matrix metalloproteinase (MMP)-2 and urokinase-type plasminogen activator (uPA). Matrilysin (MMP-7), also secreted by OMC-4 cells, was not affected by these growth factors. These results suggest that EGF and TGF-α act as positive regulators on the invasion of cervical adenocarcinoma cells, which may be associated with their stimulatory effects on tumor cell motility and the induction of type IV collagenase and uPA secreted by tumor cells.
UCN-01, a Protein Kinase C Inhibitor, Inhibits Endothelial Cell Proliferation and Angiogenic Hypoxic Response
Authors: Kruger Erwin A. , Blagosklonny Mikhail V. , Dixon Shannon C. , Figg William D.
Published: April 2003

Angiogenesis is required for tumor formation and growth; inhibition of angiogenesis is a promising new approach in cancer therapy. UCN-01, a protein kinase C (PKC) inhibitor, induces growth arrest and apoptosis in cancer cells and was recently introduced in a phase I clinical trial. We demonstrate that UCN-01, at concentrations lower than those necessary to inhibit cancer cell growth, inhibit proliferation of human endothelial cells in vitro. Moreover, UCN-01, at concentrations as low as 32 nM, prevent microvessel outgrowth from explant cultures of rat aortic rings. Since hypoxia activates hypoxia-inducible factor (HIF-1)-dependent transcription in cancer cells that, in a paracrine fashion, drive tumor angiogenesis, we investigated the effects of UCN-01 on HIF-1-responsive promoter constructs. We report that, in addition to direct inhibitory effects on endothelial cell growth, UCN-01 abrogates hypoxia-mediated transactivation of HIF-1-responsive promoters in a prostate cancer cell line. We conclude that UCN-01, at clinically relevant concentrations, exerts an anti-neovascularization effect by blocking two important steps in vessel formation: (1) the response of cancer cells to hypoxia, and (2) endothelial cell proliferation.
Human Metastatic Prostate PC3 Cell Lines Degrade Bone Using Matrix Metalloproteinases
Authors: Sanchez-Sweatman Otto H. , Orr F. William , Singh Gurmit
Published: April 2003

Bone metastases are often associated with osteolysis and subsequent pathological fractures. To determine if metastatic human cancer cells can directly degrade non-mineralized and mineralized bone, we used prostate PC3 adenocarcinoma cell lines, which were originally established from skeletal metastases. We show that PC3 cells and their conditioned medium degraded non-mineralized, osteoid-like radiolabelled extracellular matrices from human Saos2 and U2OS osteoblast-like cells. These cells also directly degraded mineralized bone by inducing 45Ca release from rat fetal calvariae and forming resorption pits on bone slices, an effect increased by transforming growth factor-β1. A role for matrix metalloproteinases in degradation was shown by: (1) stimulation by the phorbol ester TPA of PC3-induced matrix degradation and release of matrix metalloproteinase activity; (2) abrogation of matrix degradation by 1,10-phenanthroline, a metalloproteinase inhibitor, and (3) degradation of purified type I collagen by PC3 cells and their conditioned medium. We demonstrate that human prostate cancer cells can directly degrade bone-related matrices and that matrix metalloproteinases have a role in this process.
The Late Expression Factors 8 and 9 and Possibly the Phosphoprotein p78/83 of Autographa californica Multicapsid Nucleopolyhedrovirus Are Components of the Virus-Induced RNA Polymerase
Authors: Iorio Caterina , Vialard Jorge E. , McCracken Susan , Lagacé Monique , Richardson Christopher D.
Published: April 2003

Attempts were made to identify some of the subunits of the baculovirus-induced RNA polymerase following purification of its enzymatic activity by conventional chromatography. Polymerase activity was extracted from lysates of insect cells infected with Autographa californica multicapsid nucleopolyhedrovirus by polyethylenimine precipitation and subsequently purified by phosphocellulose, anion exchange, poly(A) Sepharose affinity, and gel filtration chromatography. The presence of the polymerase was monitored by its α-amanitin-resistant activity in in vitro transcription assays. A number of polypeptides associated with the enzymatic activity were identified. Peptide-specific antibodies were generated against a variety of late-expression factors (LEFs) and these antibodies, along with antisera directed against several other baculovirus proteins, were used in an immunoblot analysis of the purified polymerase. The results revealed that both the viral helicase (p143) and the virogenic stroma protein, pp31, copurify with the baculovirus-induced RNA polymerase activity through several chromatographic steps and may be loosely associated with the RNA polymerase. LEF8, LEF9 and p78/83, a nucleocapsid-associated phosphoprotein, were found to associate with the viral-induced polymerase activity. LEF8 and LEF9 contain regions of sequence homology with components of other DNA-directed RNA polymerases, while a portion of p78/83 exhibits some homology to the sigma factor of bacterial RNA polymerase, the RAP30 protein found in the mammalian transcription complex TFIIF, and the RAP94 polypeptide associated with vaccinia virus RNA polymerase. The p78/83 protein has previously been shown by our laboratory to be a capsid protein, but it may also play some role with the RNA polymerase. These results represent a first attempt to identify specific components of the RNA polymerase associated with infections of insect cells by A. californica nucleopolyhedrovirus.
A Prospective Study on Mother-to-Infant Transmission of Hepatitis C Virus
Authors: Zanetti Alessandro R. , Tanzi Elisabetta , Romanò Luisa , Zuin Giovanna , Minola Eliseo , Vecchi Laura , Principi Nicola
Published: April 2003

To assess the rate of mother-to-infant transmission of hepatitis C virus (HCV) and to identify potential risk factors for transmission, we followed up (mean 22.4 months, range 1–7.5 years) a cohort of 291 babies born to anti-HCV-positive mothers, 40 of whom were also HIV coinfected. Seventeen (5.8%) babies acquired HCV infection, but none became icteric. All babies developed chronic HCV infection with 16 babies showing elevated levels of ALT. The rate of transmission was higher in babies born to mothers coinfected with HIV than in those born to mothers with HCV alone (22.5 vs. 3.2%, p < 0.0001). No association was seen between a specific maternal HCV genotype and an increased risk of neonatal infection. The median level of HCV-RNA was higher in mothers who transmitted infection than in those who did not, although the ranges overlapped. In this study, maternal history of chronic liver disease, mode of delivery and type of feeding were not predictive of HCV infection.
Demography, Symptomatology, and Course of Disease in Ambulatory Zoster Patients
Authors: Meister Wolfgang , Neiss Albert , Gross Gerd , Doerr Hans-Wilhelm , Höbel Wilfried , Malin Jean-Pierre , von Essen Joachim , Reimann Birgit-Yvonne , Witke Claudia , Wutzler Peter
Published: April 2003

This survey summarises the observations of physicians who prospectively recorded clinically relevant data on their patients with an episode of herpes zoster. These included demography of patients, signs and symptoms during the prodromal phase, relevant history, description of disease at the first visit, therapeutic measures and description of disease, and occurrence of postherpetic neuralgia (pain 4–5 weeks after crusting) at the second visit. A total of 2,063 patients were reported to the data management centre. The age distribution resembles that reported in the literature including the notable increase in zoster frequency with advancing age. Almost 20% of the patients, however, were 30 years old or less, and this contrasts markedly with the published literature. Age modifies the frequency of the dermatome afflicited: more cranial and less thoracic manifestations were observed with increasing age. Almost all patients reported symptoms which may be attributed to a prodromal phase, especially pain in the affected dermatome (82%). The incidence of postherpetic neuralgia was 28%. A complicated disease course such as visceral, ocular, or otological involvement, or progression to additional dermatomes was seen in almost 10% of the patients.
Sequence Analysis of the Matrix/Nucleocapsid Gene Region of Turkey Coronavirus
Authors: Breslin Jamie J. , Smith Lynda G. , Fuller Frederick J. , Guy James S.
Published: April 2003

A reverse transcriptase, polymerase chain reaction (RT-PCR) procedure was used to amplify a segment of the genome of turkey coronavirus (TCV) spanning portions of the matrix and nucleocapsid (MN) protein genes (approximately 1.1 kb). The MN gene region of three epidemiologically distinct TCV strains (Minnesota, NC95, Indiana) was amplified, cloned into pUC19, and sequenced. TCV MN gene sequences were compared with published sequences of other avian and mammalian coronaviruses. A high degree of similarity (>90%) was observed between the nucleotide, matrix protein, and nucleocapsid protein sequences of TCV strains and published sequences of infectious bronchitis virus (IBV). The matrix and nucleocapsid protein sequences of TCV had limited homology (<30%) with MN sequences of mammalian coronaviruses. These results demonstrate a close genetic relationship between the avian coronaviruses, IBV and TCV.
Characterization of Potential Insertion Sites in the Core Antigen of Hepatitis B Virus by the Use of a Short-Sized Model Epitope1
Authors: Lachmann S. , Meisel H. , Muselmann C. , Koletzki D. , Gelderblom H.R. , Borisova G. , Krüger D.H. , Pumpens P. , Ulrich R.
Published: April 2003

Core particles of hepatitis B virus (HBV) are able to improve the immunogenicity of foreign sequences exposed on the particle surface. The insertion site in the core antigen of HBV (HBcAg) determines the surface presentation and thus the immunogenicity of the foreign sequence. For direct comparison of the value of potential insertion sites in the core antigen, we constructed vectors allowing insertions of a model marker epitope DPAFR. This epitope was inserted at the N-terminus, the c/e1 loop, behind amino acid (aa) 144 and behind aa 183 (DPAF only). In addition, we generated a mosaic construct allowing the co-expression of HBcAg and a HBcAg/DPAFR fusion protein due to a suppressor tRNA-mediated readthrough mechanism. All 6 constructs allowed the formation of chimaeric or mosaic core-like particles. Western blot analyses and a direct ELISA demonstrated the presence of the DPAFR sequence in the chimaeric and mosaic particles. Competitive ELISA and immune electron-microscopic data suggested the c/e1 loop as the insertion site of choice for presenting foreign sequences on the surface of chimaeric HBV core particles. However, the N-terminal fusion also allowed partial surface exposure of the DPAFR motif. In contrast, in particles of constructs carrying the DPAFR insert at aa position 144 or 183, respectively, the epitope seemed not to be surface accessible.
DNA Vaccines
Authors: Encke Jens , zu Putlitz Jasper , Wands Jack R.
Published: April 2003

Chronic infections with hepatitis B (HBV) and hepatitis C (HCV) virus are worldwide problems often leading to the development of chronic liver disease and hepatocellular carcinoma. Genetic immunizations with DNA encoding for structural and nonstructural proteins of HCV and HBV in experimental mice generate a broad base CD4+ and CD8+ cellular immune response which may be required for viral clearance from the host. DNA based immunization is a promising antiviral approach for the development of therapeutic and prophylactic vaccine against HBV and HCV.
New Antiviral Agents for the Therapy of Chronic Hepatitis B Virus Infection
Authors: Zoulim Fabien , Trepo Christian
Published: April 2003

The development of new antiviral strategies for the treatment of chronic hepatitis B remains a major goal since hepatitis virus (HBV) is resistant to interferon treatment as well as to new nucleoside analogs. HBV is a small DNA virus that replicates its genome via a reverse transcription step. The viral polymerase has been the main viral target that was studied to design new antiviral treatments. Active research has led to the discovery of new nucleoside analogs that are potent inhibitors of the viral reverse transcriptase. Among them, lamivudine has also proven antiviral efficacy in clinical trials with a sustained inhibition of viral replication. However, due to the kinetics of viral clearance, long-term antiviral therapy is necessary to eradicate viral infection. These prolonged regimens are associated with the emergence of drug-resistant strains that harbor mutations in the viral polymerase gene within the conserved B and C domains. New approaches using combinations of nucleoside analogs or other strategies, such as immune intervention (DNA vaccine, stimulation of the TH1 response ) or gene therapy (antisense oligonucleotides, dominant negative mutants), should therefore be evaluated in animal models to optimize the current antiviral protocols.
Processing and Functions of Hepatitis C Virus Proteins
Authors: Suzuki Ryosuke , Suzuki Tetsuro , Ishii Koji , Matsuura Yoshiharu , Miyamura Tatsuo
Published: April 2003

Hepatitis C virus (HCV) has a positive-stranded RNA genome of about 9.5 kb and a large open reading frame encoding a precursor polyprotein of ca. 3,000 amino acids (aa). This polyprotein is cleaved by host cellular signalase(s) and viral proteases into 10 viral proteins in the order of NH2-Core-E1-E2-p7-NS2-NS3-NS4A-NS4B-NS5A-NS5B-COOH. Core and E1/E2 are considered to be a capsid protein and envelope glycoproteins, respectively. NS2–NS5B are putative nonstructural proteins involved in the replication of HCV. NS2/3 is a metalloprotease which cleaves in cis at the NS2/3 junction. NS3 possesses serine protease and RNA helicase activities and is responsible for the cleavage of the remaining nonstructural proteins. NS4A is suggested to be a cofactor for NS3 protease. Although the function of p7, NS4B and NS5A are still unknown, an association of a mutation in NS5A with a susceptibility to interferon (IFN) has been reported. NS5B possesses an RNA-dependent RNA polymerase activity. Most of the current findings in HCV proteins depend on expression studies of HCV cDNA clones because of the lack of an efficient replication system in cell cultures. Therefore, a final assignment of cleavages and functions of HCV proteins has to await the propagation of HCV in cell cultures.
Delayed Expression of Adeno-Associated Virus Vector DNA
Authors: Afione Sandra A. , Wang Jianming , Walsh Scott , Guggino William B. , Flotte Terence R.
Published: April 2003

Two previous reports indicated that recombinant adeno-associated virus (rAAV) vectors were dependent on helper adenovirus (Ad) for efficient conversion of single-stranded (ss) rAAV DNA to the double-stranded (ds) form. This finding is somewhat paradoxical, however, since during a latent infection wild-type (wt)-AAV is rapidly converted to a ds form in the absence of Ad. Our hypothesis was that the effect observed in the previous studies was due to kinetic factors, i.e. to a relative delay in conversion to ds-DNA rather than to an absolute requirement for Ad. To test this, Hela cells were infected with a rAAV-CMV-green fluorescent protein (GFP) vector either in the presence or absence of Ad. Within the first 2 days, Ad infection resulted in a 4-fold increase in AAV vector expression and an augmentation of conversion to a ds-AAV DNA. By 6 days, however, the total number of GFP-expressing cells in the Ad-free culture had exceeded the original number in the Ad co-infected cells, and the conversion to ds-DNA episomes was substantial and ongoing.
PCR-RFLP-Detected Human Papilloma Virus Infection in a Group of Senegalese Women Attending an STD Clinic and Identification of a New HPV-68 Subtype
Authors: Astori G. , Beltrame A. , Pipan C. , Raphenon G. , Botta G.A.
Published: April 2003

Cancer of the cervix is the most common malignant tumor among women in Africa and, in particular, Senegal. Studies of the prevalence of human papilloma virus (HPV) infection in Africa have mainly focused on carcinomas. Data on the presence of the virus in women with normal cervical cytology are scarce. In this study, 158 cytologically normal women who had been referred to the ‘Institut Pasteur de Dakar’ (Senegal) for various genital complaints were investigated for the presence of HPV on exfoliated cells by PCR-RFLP. HPV was detected in 13.9% of cases. Oncogenic type HPV 16 was the most common type (40.9%), followed by HPV 53 and HPV 58, both detected in 13.6% of cases. Mixed HPV infections were present in 13.6% of the subjects. Only HPVs belonging to the intermediate-high risk group were detected. These data suggest the need for careful cytological control of patients. A PCR-HPV fragment (GA115) possessing an original RFLP pattern was isolated. After sequencing, it showed a nucleotide homology of 97.1% with HPV 68 and should therefore be considered a new HPV 68 subtype. The use of PCR-RFLP strategy enables detection and typing of all known and as yet unknown genital HPVs. Variant and subtype classification of HPV types identified by oligonucleotide probe methods may need to be refined, especially for less prevalent HPVs and in areas where little information on HPV prevalence is available. More studies are needed to characterize satisfactorily the epidemiology of HPV in Africa.
The Hepatitis B Virus Pregenome: Prediction of RNA Structure and Implications for the Emergence of Deletions
Authors: Kidd-Ljunggren Karin , Zuker Michael , Hofacker Ivo L. , Kidd Alistair H.
Published: April 2003

The terminally redundant pregenomic RNA of human hepatitis B virus (HBV) comprises some 3,330 nucleotides and is a replicative intermediate in the production of the circular DNA genome. Deletions are known to arise in the HBV genome during the course of chronic infection and are sometimes associated with interferon therapy. These deletions are limited to small parts of the genome such as the 357-nucleotide pre-S1 region. Long RNA molecules such as the HBV pregenome have considerable structural flexibility and will undergo secondary structure shifts between energetically favourable states in a continuous and semi-random fashion. Since prediction of structure elements that are highly conserved in different forms of one RNA molecule is now feasible by computer modelling, we have analysed the whole HBV pregenome by two different RNA structure prediction algorithms and by new methods that exploit these algorithms. Significantly, the ends of pregenomic RNA were predicted to undergo both short-range and long-range interactions, which has relevance to our knowledge of the virus replicative cycle. By incorporating phylogenetic information relating to the 6 recognised genotypes of HBV, it was possible to highlight short secondary structures that may be common to all HBV strains. For example, although the pre-S1 region was predicted to undergo local folding of a loosely defined nature, most observed pre-S1 deletions mapped to all or part of an arm carrying a better-defined structure. The loss of such sequences may be mechanistically attributable to polymerase skipping during reverse transcription, and the possible advantages of such deletions are considered.
Relationship between Five-Year Histological Outcome and Serial Changes in Serum Alanine Aminotransferase in Patients with Biochemical and Virological Relapse after Interferon Treatment for Chronic Hepatitis C
Authors: Kobayashi Masahiro , Ikeda Kenji , Akuta Norio , Someya Takashi , Suzuki Fumitaka , Tsubota Akihito , Suzuki Yoshiyuki , Saitoh Satoshi , Arase Yasuji , Chayama Kazuaki , Kumada Hiromitsu
Published: April 2003

Objective: The aim of this study was to assess the correlation between serial changes in serum alanine aminotransferase (ALT) levels and histological outcome 5 years after treatment of patients with chronic hepatitis C with interferon (IFN). Methods: We retrospectively evaluated 61 consecutive patients who underwent two liver biopsies, just before and 5 years after a 6-month course of IFN therapy, and who showed a relapse after therapy. The extent of liver fibrosis was estimated using a scale with seven grades. Results: At the end of 6-month IFN therapy, 40 (65.6%) patients had normal serum ALT concentrations. However, 13 of the 40 patients relapsed within 6 months after IFN therapy. The average ALT during 5 years in 40 patients was less than or equal to 75 IU/l, while in the other 21 patients it was more than 75 IU/l. Among the 40 patients with a mean ALT less than 75 IU/l, 13 (33%) patients showed histological improvement, 26 (65%) showed no changes and only 1 patient (2%) showed worsening of liver fibrosis. On the other hand, among the 21 patients with a mean ALT of more than 75 IU/l, only 1 (5%) patient showed improvement, 8 (38%) showed no changes and 12 patients (57%) showed worsening of liver fibrosis. Conclusion: There is a significant relationship between 5-year histological outcome and serial changes in serum ALT in patients with biochemical and virological relapse after IFN treatment for chronic hepatitis C.
In vitro Tumor Angiogenesis Assays: Plasminogen Lysine Binding Site 1 Inhibits in vitro Tumor-Induced Angiogenesis
Authors: Barendsz-Janson Annemarie F. , Griffioen Arjan W. , Muller Annemarie D. , van Dam-Mieras Maria C.E. , Hillen Harry F.P.
Published: April 2003

It is generally accepted that tumors are angiogenesis-dependent. For research and clinical purposes it would be very attractive to have a simple in vitro model that allows a rapid screening of the angiogenic potential of tumors and to study the effect of angiogenic inhibitors. In vitro angiogenesis models were developed, based on endothelial sprouting/tube formation on a collagen gel, using both tumor cell lines and tumor biopsies. Best results were obtained using conditioned medium of tumor cell lines. In this model it was found that the plasminogen fragment lysine binding site 1 (LBS-1) inhibited in vitro endothelial cell sprouting. This is the first demonstration that LBS-1, which includes angiostatin, is inhibitory for new vessel formation in an in vitro angiogenesis model. We conclude that the assay system allows for rapid and reliable screening of angiogenesis inhibitors.