bluuebunny/crossref_metadata_2025 huggingface dataset:
Cytotoxic T lymphocyte responses to wild‐type and mutant mouse p53 peptides
Authors: Bertholet Sylvie , Iggo Richard , Corradin Giampietro
Published: March 2007

Cytotoxic T lymphocytes (CTL) recognize peptides presented at the cell surface in association with major histocompatibility complex (MHC) class I molecules. The finding that peptides binding to MHC class I molecules share common amino acid motifs renders feasible the selection of antigenic peptides by simply scanning protein sequences, and thus, provides the possibility of inducing CTL to pre‐defined specificities. Tumor cells possess antigens known to generate MHC class I‐restricted CD8+ CTL responses. Thus, these antigens represent good targets to induce tumor‐specific immunity. Among these antigens, the p53 tumor suppressor gene product is an attractive candidate for cancer immunotherapy. Mutations in the p53 gene have been found to be very frequently associated with a malignant transformation and often lead to p53 protein overexpression. Thus, we investigated the possibility of inducing CTL to wild‐type or mutant p53 peptides in a BALB/c (H‐2d) mouse model. Peptides possessing the H2‐Kd binding motif were selected and tested for binding to the H‐2Kd molecules in vitro. Synthetic peptides p53122–130 wild‐type or “mutant” (Lys → Glu substitution at position 129) were shown to be the best binder peptides and were tested for their immunogenicity in mice. H‐2Kd‐restricted p53‐specific CD8+ CTL were generated following immunization of mice with either wild‐type (wt) p53122–130 or mutant (mut) p53122–130 (E129) peptides. Only low‐affinity CTL can be obtained by immunization with the wt sequence. In contrast, CTL elicited with the mut peptide recognized the mut sequence at a 10–100‐fold lower concentration. This indicates that CTL elicited with the mut peptide recognized the mut sequence very efficiently, whereas the wt sequence is poorly recognized, if at all. Taken together, these results thus suggest that p53‐specific tumor immunotherapy may be successful only if the mutated protein is taken into consideration.
Diffuse large cell lymphomas are derived from mature B cells carrying V region genes with a high load of somatic mutation and evidence of selection for antibody expression
Authors: Küppers Ralf , Rajewsky Klaus , Hansmann Martin‐Leo
Published: March 2007

In the Revised European American Lymphoma (REAL) classification, several subtypes of high‐grade lymphomas were combined in the entity diffuse large cell lymphoma (DLL). In the present study, a total of 19 cases of DLL (10 cases of centroblastic lymphoma, 5 cases of mediastinal B cell lymphoma, 2 cases of immunoblastic lymphoma, 1 case of T cell‐rich B lymphoma and one case of large cell anaplastic lymphoma) were analyzed for somatically mutated immunoglobulin V region genes. Somatic mutations are acquired in the course of the germinal center (GC) reaction and are thus found in GC B cells and their descendants, i.e. memory B cells. The V gene sequences revealed that the tumor cells of all five subtypes of DLL harbored mutated V region genes and are thus derived from antigen‐experienced (post) GC B cells. This indicates that from the point of view of the stage of development of the tumor precursor, the combination of those five subtypes to one entity, i.e. DLL, seems reasonable. In some cases, an unusually high frequency of somatic mutations was detected. This may indicate that DLL are derived from GC B cells, which, due to transforming events, stayed in the GC for prolonged periods of time, thereby accumulating a high load of somatic mutation. An analysis of the mutation pattern suggests that the tumor clone or its precursor were selected for antibody expression while acquiring somatic mutations. The latter observation discriminates DLL from classical Hodgkin's disease, where we recently also observed a high load of somatic mutation within rearranged V region genes, but a frequent occurrence of crippling mutations.
Conversion in vivo from an early dominant Th0/Th1 response to a Th2 phenotype during the development of collagen‐induced arthritis
Authors: Doncarli Alexandra , Stasiuk Lisa M. , Fournier Catherine , Abehsira‐Amar Orly
Published: March 2007

Over the past decade, the central role of T cells in the process of collagen‐induced arthritis (CIA) has been extensively documented. The inflammatory features of CIA and its successful modulation after treatment in vivo with Th2 lymphokines, known to down‐regulate proinflammatory cytokines, classify CIA as a Th1‐mediated disease. However, no direct evidence for the presence of the different T helper subsets has been obtained. To identify the collagen‐specific CD4+ T cell subset(s) developing during the course of CIA, lymph nodes from susceptible DBA/1 mice (H‐2q) were harvested at different times after injection of bovine type II collagen in Freund's complete adjuvant and checked by enzyme‐linked immunospot assay for the production of interferon (IFN)‐γ and interleukin (IL)‐4. The results clearly showed that type II collagen‐specific T cells secreting either IFN‐γ, IL‐4, or both, develop early in vivo, before the onset of arthritis: the number of IFN‐γ‐secreting cells was already maximal 15 days after immunization, whereas more IL‐4‐secreting cells were found at day 30, just before the onset of clinical arthritis. Another strategy was to establish collagen‐specific CD4+ T cell lines and sublines in vitro and to analyze their lymphokine secretion pattern. Lines generated 8 days after immunization displayed a mixed lymphokine secretion pattern characteristic of Th0 cells or of a mixture of Th1 and Th2 cells. After limiting dilution of a day 8 line, 60% of the growing sublines were Th0‐like (secreting IFN‐γ, IL‐4, and IL‐5), and 25% were Th1 (secreting IFN‐γ). By day 25 post‐immunization, 33% of the generated sublines were Th0‐like, 11% Th1, and 56% Th2 (secreting IL‐4 and IL‐5). Moreover, all the sublines raised from the lymph nodes of arthritic mice harvested at day 55 secreted high amounts of Th2 lymphokines, and only 3 out of 14 also produced some IFN‐γ. This study demonstrates that during the course of CIA the collagen‐specific CD4+ T cell response shifts in vivo from a dominant Th0/Th1 response to a clear Th2 phenotype. These results contribute to our understanding of the collagen‐specific CD4+ T helper subsets which develop during the induction and clinical phases of CIA.
The defined attenuated Listeria monocytogenes Δmpl2 mutant is an effective oral vaccine carrier to trigger a long‐lasting immune response against a mouse fibrosarcoma
Authors: Paglia Paola , Arioli Ivano , Frahm Nicole , Chakraborty Trinad , Colombo Mario P. , Guzmàn Carlos A.
Published: March 2007

Listeria monocytogenes has been proposed as a carrier to elicit major histocompatibility complex class‐I restricted immune responses able to protect against tumor challenge. In this study the properties of the attenuated L. monocytogenes Δmpl2 mutant has been evaluated in vivo against a highly aggressive mouse fibrosarcoma which expresses β‐galactosidase (β‐gal) as a tumor‐associated antigen (TAA). Immunization with the vaccine prototypes resulted in both elicitation of specific antibodies and generation of cytotoxic lymphocytes (CTL). Oral vaccination protected 55–64% of the immunized animals from tumor take (p < 0.01) and strongly reduced the average size of the tumor in the other 34–45% (p < 0.01). Vaccinated mice developed a long‐lasting response, which resulted in 100% protection from a subsequent tumor challenge. Substitution of the whole TAA by its CTL‐defined immunodominant epitope resulted in 43% protection, suggesting a contribution of the humoral response to the observed antitumor effect. No statistically significant differences were observed in the antitumor response when mice were immunized with strains expressing the immunodominant TAA epitope in the context of carrier proteins which were either exported or restricted to the bacterial cytoplasm. This suggests that the topology of the recombinant antigen does not play a major role in the outcome of the protective response.
The chemokine SDF‐1, stromal cell‐derived factor 1, attracts early stage B cell precursors via the chemokine receptor CXCR4
Authors: D'Apuzzo Massimo , Rolink Antonius , Loetscher Marcel , Hoxie James A. , Clark‐Lewis Ian , Melchers Fritz , Baggiolini Marco , Moser Bernhard
Published: March 2007

In the bone marrow, progenitor (pro‐) and precursor (pre‐) B cells depend on close contact with stromal cells for growth and maturation. Stromal cell‐derived factor 1 (SDF‐1), also known as pre‐B cell growth‐stimulating factor, is produced by bone marrow stromal cells and was reported to act together with interleukin‐7 as co‐mitogen for pre‐B cells. SDF‐1 was recently shown to be a chemokine which is chemotactic for different types of leukocytes and acts via the chemokine receptor CXCR4. Using sorted B220+ bone marrow cells and several B cell lines characteristic for different stages of B lymphopoiesis, we now show that SDF‐1 is a potent attractant for pro‐ and pre‐B cells, but is inactive on B cells at later stages of development. In early B cell precursors, SDF‐1 induced intracellular Ca2+ mobilization and in vitro migration with a potency and efficacy similar to that observed for chemokines acting on blood leukocytes. These responses were mediated via CXCR4 as they could be inhibited by an anti‐receptor antibody. SDF‐1 is the first chemokine shown to act on early‐stage B cell precursors. Mice lacking SDF‐1 die perinatally and show a severe deficiency in B lymphopoiesis. We propose that SDF‐1 released from the stromal cells exerts its critical hematopoietic function by selectively attracting and confining early B cell precursors within the bone marrow microenvironment that provides the necessary factors for growth and differentiation.
Src family‐selective tyrosine kinase inhibitor, PP1, inhibits both FcεRI‐ and Thy‐1‐mediated activation of rat basophilic leukemia cells
Authors: Amoui Mehran , Dráber Petr , Dráberová Lubica
Published: March 2007

Cross‐linking of the surface receptor with high affinity for IgE (FcεRI) by multivalent antigen/immunoglobulin E complexes, as well as aggregation of Thy‐1 glycoprotein by monoclonal antibodies lead in rat basophilic leukemia cells, clone RBL‐2H3, to tyrosine phosphorylation of several cellular proteins, followed by a release of secretory components. To investigate the molecular mechanisms of FcεRI‐ and Thy‐1‐mediated transmembrane signaling and to map a step at which they converge into a common secretory pathway, we used a novel Src family‐selective tyrosine kinase inhibitory, 4‐amino‐5‐(4‐methylphenyl)‐7‐(t‐butyl)pyrazolo[3,4‐d]pyrimidine (PP1), and analyzed its inhibitory activity on cell activation. Here we show that in RBL‐2H3 cells PP1 demonstrates substrate specificity for a Src family kinase Lyn. In immunocomplex kinase assays in vitro, PP1 inhibited the Lyn kinase activity at nanomolar levels without any effect on Syk kinase activity. However, in RBL cells activated via aggregation of FcεRI, phosphorylation of both Syk and Lyn kinases was inhibited. FcεRI‐ and Thy‐1‐mediated early (protein‐tyrosine phosphorylation) and late (release of β‐hexosaminidase) activation events were similarly affected by PP1. The inhibition was specific for membrane receptor‐mediated signaling and was not observed in cells activated by an exposure to pervanadate. The combined data suggest that activation of Lyn is the early activation step at which the FcεRI‐ and Thy‐1‐mediated activation pathways of mast cells and basophils may converge.
Differential T cell receptor‐mediated signaling in naive and memory CD4 T cells
Authors: Farber Donna L. , Acuto Oreste , Bottomly Kim
Published: March 2007

Naive and memory CD4 T cells differ in cell surface phenotype, function, activation requirements, and modes of regulation. To investigate the molecular bases for the dichotomies between naive and memory CD4 T cells and to understand how the T cell receptor (TCR) directs diverse functional outcomes, we investigated proximal signaling events triggered through the TCR/CD3 complex in naive and memory CD4 T cell subsets isolated on the basis of CD45 isoform expression. Naive CD4 T cells signal through TCR/CD3 similar to unseparated CD4 T cells, producing multiple tyrosine‐phosphorylated protein species overall and phosphorylating the T cell‐specific ZAP‐70 tyrosine kinase which is recruited to the CD3ζ subunit of the TCR. Memory CD4 T cells, however, exhibit a unique pattern of signaling through TCR/CD3. Following stimulation through TCR/CD3, memory CD4 T cells produce fewer species of tyrosine‐phosphorylated substrates and fail to phosphorylate ZAP‐70, yet unphosphorylated ZAP‐70 can associate with the TCR/CD3 complex. Moreover, a 26/28‐kDa phosphorylated doublet is associated with CD3ζ in resting and activated memory but not in naive CD4 T cells. Despite these differences in the phosphorylation of ZAP‐70 and CD3‐associated proteins, the ZAP‐70‐related kinase, p72syk, exhibits similar phosphorylation in naive and memory T cell subsets, suggesting that this kinase could function in place of ZAP‐70 in memory CD4T cells. These results indicate that proximal signals are differentially coupled to the TCR in naive versus memory CD4 T cells, potentially leading to distinct downstream signaling events and ultimately to the diverse functions elicited by these two CD4 T cell subsets.
In vitro responses of human CD45R0brightRA− and CD45R0−RAbright T cell subsets and their relationship to memory and naive T cells
Authors: Young Joyce L. , Ramage Judith M. , Gaston J. S. Hill , Beverley Peter C. L.
Published: March 2007

The cellular basis of immunological memory, particularly with respect to T cells is not understood. In humans, monoclonal antibodies to CD45 have been used to identify memory (CD45R0) and naive (CD45RA) T cells. However, this identification has been called into question by various studies which suggest that high molecular weight CD45 isoforms may be re‐expressed by previously activated cells. In the present study, using cultures which supported responses of naive T cells, we examined the responses of purified CD45R0brightRA− or CD45R0−‐RAbright T cell subsets. The former subset was found to respond preferentially to recall antigens with minimal responses apparent to neo‐(or non‐recall)‐antigens. The inverse pattern was found for CD45R0−RAbright T cells, which converted to CD45R0brightRA− after stimulation with a neo‐antigen. Moreover, the two populations of T cells exhibited distinct response kinetics with a faster response evident from the CD45R0brightRA−T cells compared to the CD45R0−RAbright subset. The poor responses of CD45R0−RAbright T cells to recall antigens compared to neo‐antigens suggests that this putative naive population is specifically depleted of reactive T cells following an encounter with antigen. We propose that T cell priming results in the stimulation of many CD45R0−RAbright T cells with various T cell receptor specificities from which memory T cells are selected for survival. If re‐expression of higher molecular weight isoforms does occur in humans in vivo, our results suggest that R0 expression would be retained (CD45R0+RA+). Alternatively, if primed CD45R0−RAbright T cells exist, they are not prevalent in peripheral blood and thus may be sequestered within lymphoid tissues. Our data support the view that in human peripheral blood, CD45R0bright and CD45RAbright expression identify memory and naive CD4+ T cells, respectively.
Crucial role of marginal zone macrophages and marginal zone metallophils in the clearance of lymphocytic choriomeningitis virus infection
Authors: Seiler Peter , Aichele Peter , Odermatt Bernhard , Hengartner Hans , Zinkernagel Rolf M. , Schwendener Reto A.
Published: March 2007

Macrophages play a key role in the immune defense against pathogens. They control early invasion by antigen‐unspecific phagocytosis of pathogens and act as professional antigen‐presenting cells to induce antigen‐specific T cell responses. To investigate the involvement of particular subsets of the splenic macrophages in an antiviral immune response, we selectively depleted mice of splenic marginal zone macrophages (MZM) and marginal zone metallophils (MM) using the clodronate liposome depletion technique. MZM‐ and MM‐depleted mice were not able to control an infection with lymphocytic choriomeningitis virus (LCMV). In these mice, LCMV spread from the spleen to peripheral organs at an early phase of infection. The virus‐specific cytotoxic T lymphocyte (CTL) response was induced initially, yet was exhausted in parallel with the overwhelming virus replication. These findings suggest that MZM and MM play a crucial role in the early control of a LCMV infection by preventing immediate virus spread to peripheral organs, but are not essential for the induction of the LCMV‐specific CTL response.
Comparison of the effects of interleukin‐1α, interleukin‐lβ and interferon‐γ‐inducing factor on the production of interferon‐γ by natural killer
Authors: Hunter Christopher A. , Timans Jackie , Pisacane Paul , Menon Satish , Cai Guifang , Walker William , Aste‐Amezaga Miguel , Chizzonite Richard , Bazan J. Fernando , Kastelein Robert A.
Published: March 2007

Interferon‐γ inducing factor (IGIF) is a recently identified cytokine which stimulates the production of interferon‐γ (IFN‐γ) by T cells and enhances natural killer (NK) cell cytolytic activity. Protein fold recognition, structure prediction and comparative modeling have revealed that IGIF is a member of the interleukin (IL)‐1 cytokine family and has prompted the designation IL‐1γ. Here we report functional similarities between members of the IL‐1 family by comparing the effects of IL‐1α, IL‐1β and IGIF on NK cell production of IFN‐γ. All three IL‐1 types enhanced NK cell production of IFN‐γ when induced by IL‐2 or IL‐12, although at high concentrations (>10 ng/ml), IGIF was five‐ to tenfold more potent than IL‐1α or IL‐1β. This effect correlated with enhanced levels of mRNA for IFN‐γ when NK cells were stimulated with IGIF plus IL‐12. In contrast to IL‐12 and IL‐2, the ability of IGIF to stimulate NK cell production of IFN‐γ was not increased by IL‐1α or IL‐1β. The ability of IGIF to enhance IFN‐γ production was independent of the type I and type II IL‐1 receptors or the IL‐1R accessory protein. Together, these results identify IGIF as a potent stimulator of NK cell production of IFN‐γ and demonstrate that the effect of IGIF on NK cell production of IFN‐γ is similar to that of IL‐1α and IL‐1β but distinct from that of IL‐12.
CD4+ T cells of both the naive and the memory phenotype enter rat lymph nodes and Peyer's patches via high endothelial venules: Within the tissue their migratory behavior differs
Authors: Westermann Jürgen , Geismar Ulrike , Sponholz Angélique , Bode Ulrike , Sparshott Sheila M. , Bell Eric B.
Published: March 2007

It is thought that naive T cells predominantly enter lymphoid organs such as lymph nodes (LN) and Peyer's patches (PP) via high endothelial venules (HEV), whereas memory T cells migrate mainly into non‐lymphoid organs. However, direct evidence for the existence of these distinct migration pathways in vivo is incomplete, and nothing is known about their migration through the different compartments of lymphoid organs. Such knowledge would be of considerable interest for understanding T cell memory in vivo. In the present study we separated naive and memory CD4+ T cells from the rat thoracic duct according to the expression of the high and low molecular weight isoforms of CD45R, respectively. At various time points after injection into congenic animals, these cells were identified by quantitative immunohistology in HEV, and T and B cell areas of different LN and PP. Three major findings emerged. First, both naive and memory CD4+ T cells enter lymphoid organs via the HEV in comparable numbers. Second, naive and memory CD4+ T cells migrate into the B cell area, although in small numbers and continuously enter established germinal centers (GC) with a bias for memory CD4+ T cells. Third, memory CD4+ T cells migrate faster through the T cell area of lymphoid organs than naive CD4+ T cells. Thus, our study shows that memory CD4+ T cells are not excluded from the HEV route. In addition, “memory” might depend in part on the ability of T cells to specifically enter the B cell area and GC and to screen large quantities of lymphoid tissues in a short time.
Cross talk between αvβ3 and α4β1 integrins regulates lymphocyte migration on vascular cell adhesion molecule 1
Authors: Imhof Beat A. , Weerasinghe Dheepika , Brown Eric J. , Lindberg Frederic P. , Hammel Philippe , Piali Luca , Dessing Mark , Gisler Roland
Published: March 2007

Local inflammation leads to increased expression of the vascular cell adhesion molecule (VCAM)‐1 on vascular endothelium which contributes to the encapture of leukocytes from the circulating blood through the leukocyte ligand α4β1 integrin. Inflammatory vascular endothelium expresses VCAM‐1 at high density. We found that the speed of locomotion of activated lymphocytes migrating along surfaces coated with recombinant VCAM‐1 at a comparable density to that found on inflammatory endothelium was slow. However, lymphocytes do migrate and extravasate rapidly under inflammatory conditions, indicating that there must be mechanisms that regulate the interaction between α4β1 and VCAM‐1 in vivo. Here we show that the lymphocyte αβ3 integrin and integrin‐associated protein (IAP) is able to regulate this interaction. The occupancy of lymphocyte αvβ3 integrin by platelet cell adhesion molecule‐1 or vitronectin regulated the speed of α4β3 integrin‐dependent locomotion of lymphocytes on recombinant VCAM‐1. This allowed rapid lymphocyte migration at VCAM‐1 densities which are typical of inflammatory vessels. This αvβ3‐mediated enhanced migration of lymphocytes via α4β1 is likely to depend on the interaction of αvβ3 integrin with the IAP. Furthermore, this motile process correlates with polarization of the actin cytoskeleton in lymphocytes. Our results suggest that cross talk between αvβ3 integrin and α4β1 integrin is a mechanism in the regulation of lymphocyte locomotion along inflammatory endothelium and subsequent transendothelial migration. This can explain how lymphocytes overcome tight adhesion to the vascular endothelium and start rapid migration along and through the endothelial lining of blood vessels into inflammatory tissue.
Single‐cell analysis of intrathyroidal lymphocytes shows differential cytokine expression in Hashimoto's and Graves' disease
Authors: Roura‐Mir Carme , Catálfamo Marta , Sospedra Mireia , Alcalde Laura , Pujol‐Borrell Ricardo , Jaraquemada Dolores
Published: March 2007

Most human organ‐specific autoimmune diseases such as Hashimoto's thyroiditis (HT) are considered to be Th1 mediated, and a quantitative dominance of Th1 cells in thyroid infiltrates from both Graves' disease (GD) and HT affected glands has been reported. However, Th2 dominance would be expected in GD, where thyroid hyperfunction induced by stimulating antibodies predominates over tissue destruction. We have analyzed the interleukin‐4 (IL‐4), interferon‐γ (IFN‐γ) production by T cells at the single‐cell level, both in infiltrating lymphocytes isolated from digested GD and HT thyroid glands and in derived T cell lines, by direct intracellular cytokine detection. Results showed a heterogeneous pattern of cytokine production in bulk GD infiltrates and derived T cell lines, and a similar pattern was observed in the much larger HT infiltrates. Both type 1 and type 2 cytokines were simultaneously produced by the infiltrating populations, and T cells with both patterns as well as intermediate patterns similar to ThO cells could be detected ex vivo. However, the larger T lymphocytes, presumably activated and responsible for the autoimmune damage, predominantly produced IL‐4 in GD and IFN‐γ in HT. The specificity of the Th2 responses in GD was suggested by the enrichment in IL‐4 production after antigen‐specific expansion of two oligoclonal T cell lines. These data show that both type 1 and type 2 cytokines are produced in the thyroid glands affected by autoimmunity and that the difference between diseases may be the effect of a functionally dominant population at a given time. This in vivo chronically activated antigen‐specific population, producing type 1 or type 2 cytokines locally, may be responsible for the effect finally leading to one of the disease states.
Voltammetric Study of Reduction Processes in Rhodium(+3)–Selenium(+4) Acidic Mixtures
Authors: Zelić Marina , Strmečki Slađana
Published: March 2007

Using square‐wave voltammetry and linear scan voltammetry, some reduction processes, that take place on the hanging mercury drop electrode (HMDE) in rhodium(+3)–selenium(+4) mixtures, were studied in highly acidic sulfate, chloride and perchlorate solutions. The special attention was paid to the peak located at −1.1 V, that reflects catalytic hydrogen evolution on the rhodium islets, and its changes under the influence of added selenium(+4), or selenium(−2) produced at the electrode. It can be concluded that addition of selenite to a dilute rhodium solution has the similar effect as the increase of rhodium(+3) concentration, making the catalytic hydrogen evolution more pronounced, probably by changing the properties of metal clusters on the mercury drop. If so, the effect could be of some practical importance in production of rhodium deposits on other surfaces, too.
Electroanalytical Study of the Composition of the Raw Pigment Mixtures that Yield the Metallic Lustre on Ceramics. A Link Between Composition and Final Result
Authors: Cepriá G. , Roque J. , Molera J. , Pérez‐Arantegui J. , Vendrell M.
Published: March 2007

Voltammetry of immobilized microparticles was used to study the electrochemistry of the raw pigments that produce the metallic lustre on ceramics after a successful firing. To study this influence of the mixture components on the reduction properties to achieve the metallic lustre, 14 mixtures of illitic clay, Fe2O3, HgS, CuO and AgNO3 were prepared and studied in different media. Iron oxide improves the yield of the reduction of the metals and cinnabar helps a closer reduction of silver to copper reduction and prevents the AgCu alloying because of the formation of silver–mercury adducts. The presence of one of the metals influences the peak position of the other metal. The use of vinegar as diluting agent is not casual, because in this media the reduction of silver takes place at a potential closer to the copper. This electroanalytical technique allowed to distinguish between powders of different composition and offered some information about the role of the components in the reduction of copper and silver and the selection of vinegar to prepare the raw pigment suspensions.
Estimation of inelastic seismic deformations in asymmetric multistorey RC buildings
Authors: Kosmopoulos A. J. , Fardis M. N.
Published: March 2007

Four real buildings with three to six stories, strong irregularities in plan and little engineered earthquake resistance are subjected to inelastic response‐history analyses under 56 bidirectional EC8‐spectra‐compatible motions. The average chord rotation demand at each member end over the 56 response‐history analyses is compared to the chord rotation from elastic static analysis with inverted triangular lateral forces or modal response spectrum analysis. The storey‐average inelastic‐to‐elastic‐chord‐rotation‐ratio was found fairly constant in all stories, except when static elastic analysis is applied to buildings with large higher mode effects. Except for such buildings, static elastic analysis gives more uniform ratios of inelastic chord rotations to elastic ones within and among stories than modal response spectrum analysis, but generally lower than 1.0. With increasing EPA the building‐average inelastic‐to‐elastic‐chord‐rotation‐ratio decreases but scatter in the results increases. Static elastic analysis tends to overestimate the inelastic torsional effects at the flexible or central part of the torsionally flexible buildings and underestimate them at their stiff side. Modal response spectrum analysis tends to overestimate the inelastic torsional effects at the stiff or central part of the torsionally stiff buildings and underestimate them at the flexible side. Overall, for multistorey RC buildings that typically have fundamental periods in the velocity‐sensitive part of the spectrum, elastic modal response spectrum analysis with 5% damping gives on average unbiased and fairly accurate estimates of member inelastic chord rotations. If higher modes are not significant, elastic static analysis in general overestimates inelastic chord rotations of such buildings, even when torsional effects are present. Copyright © 2007 John Wiley & Sons, Ltd.
Subcellular localization of ATBF1 regulates MUC5AC transcription in gastric cancer
Authors: Mori Yoshinori , Kataoka Hiromi , Miura Yutaka , Kawaguchi Makoto , Kubota Eiji , Ogasawara Naotaka , Oshima Tadayuki , Tanida Satoshi , Sasaki Makoto , Ohara Hirotaka , Mizoshita Tsutomu , Tatematsu Masae , Asai Kiyofumi , Joh Takashi
Published: March 2007

Human gastric epithelium has a unique mucin gene expression pattern, which becomes markedly altered in gastrointestinal disorder. This alteration in mucin expression, including the mucin MUC5AC, may be related to the development and prognosis of gastric cancers, and MUC5AC‐positive gastric cancer has been reported to be poor prognosis. However, the molecular mechanism of MUC5AC transcriptional regulation has not been fully elucidated. AT motif‐binding factor 1 (ATBF1) is a homeotic transcriptional regulatory factor recently identified as a tumor suppressor gene, and its subcellular localization suggests a link to cell proliferation and differentiation. We investigated the mechanism of MUC5AC transcriptional regulation by ATBF1. In 123 gastric cancer lesions, ATBF1 expressed in the nucleus significantly suppressed MUC5AC expression, as determined by immunohistochemistry. In addition, analysis of the MUC5AC promoter region revealed an AT motif‐like element. This element was found to be essential for ATBF1 suppression of MUC5AC promoter activity as shown in a dual luciferase‐reporter assay. Over‐expressed ATBF1 also significantly suppressed endogenous MUC5AC protein expression in gastric cancer cells. Chromatin immunoprecipitation demonstrated that ATBF1 binds to the AT motif‐like element in the MUC5AC promoter. These results indicate that ATBF1 in the nucleus negatively regulates the MUC5AC gene in gastric cancer by binding to an AT motif‐like element in the MUC5AC promoter. © 2007 Wiley‐Liss, Inc.
The proteins of hepatitis B dane particle cores
Authors: Hruska Jerome F. , Robinson William S.
Published: March 2007

Although several studies have been done to analyze the peptides of purified 22‐nm HbsAg particles, no information has been published about the peptides of the core of the Dane particle which bears the other hepatitis B viral antigen, HbcAg. Dane particles and Dane particle cores (produced by NP‐40 treatment of Dane particles) were purified by equilibrium centrifugation in CsCl density gradients. Two populations of Dane particles were observed at densities 1.27 and 1.24 g/ml, respectively. The higher buoyant density Dane particles yielded exclusively cores of buoyant density 1.38 g/ml in CsCl, and the lower buoyant density Dane particles yielded two kinds of cores with buoyant densities of 1.38 and 1.325 g/ml, respectively. Only the higher density Dane particles and cores manifested endogenously primed DNA polymerase activity. The peptides of density 1.38 g/ml Dane particle cores purified by equilibrium CsCl density gradient centrifugation and HBcAg particles from HBV infected chimpanzee liver purified in the same way were analyzed by SDS‐polyacrylamide gel electrophoresis. Both kinds of particles were found to consistently contain 3 Coomassie blue staining peptides with approximate molecular weights of 19,000, 70,000 and 80,000 daltons (designated P‐19, P‐70 and P‐80 respectively). In addition, the HBcAg particles from infected liver regularly yielded a protein component with molecular weight greater than 200,000 daltons. This component was occasionally present in electrophoresis runs of core peptides from only one of two patients. Its irregular appearance after gel electrophoresis suggests it may have been an aggregate not completely dissociated under the conditions used. The lower density core component consistently contained P‐19, P‐70, and P‐80, and infrequently additional minor peptides of uncertain origin. The irregular occurrence of the minor peptides in varying amounts suggests they were not intrinsic core proteins.
Prevalence of antibody to the Norwalk agent by a newly developed immune adherence hemagglutination assay
Authors: Kapikian Albert Z. , Greenberg Harry B. , Cline W. Lee , Kalica Anthony R. , Wyatt Richard G. , James Harvey D. , Lloyd Nancy L. , Chanock Robert M. , Ryder Robert W. , Kim Hyun Wha
Published: March 2007

An immune adherence hemagglutination assay (IAHA) for the detection of antibody to the Norwalk agent of acute epidemic nonbacterial gastroenteritis was developed using as antigen virus purified from stool from an experimentally infected volunteer. The assay was sensitive and specific and was efficient for detecting Norwalk antibody seroresponses. The prevalence of Norwalk antibody in various groups in the United States was studied. Antibody to the Norwalk agent was acquired gradually, beginning slowly in childhood and accelerating in the adult period so that by the fifth decade 50% possessed antibody. This pattern of antibody acquisition contrasted sharply with that for the human rotavirus of infantile gastroenteritis. Rotavirus antibody was acquired during early childhood by almost all individuals in the pediatric groups studied. Antibody to the Norwalk agent was also found in rural Bangladesh; in a small prevalence survey of 39 children and adults 21% possessed Norwalk IAHA antibody, whereas 95% possessed antibody to the human rotavirus.
SSPE‐BIKEN: A Naturally arising hemagglutination‐defective mutant of measles virus
Authors: Breschkin Alan M. , Morgan Exeen M. , McKimm Jennifer , Rapp Fred
Published: March 2007

Biochemical and genetic methods have been used to investigate a defective variant of measles virus previously isolated from a patient with subacute sclerosing panencephalitis (SSPE). Since its isolation, this syncytiogenic strain (SSPE‐BIKEN) has remained cell‐associated; infected cells do not hemadsorb and do not release infectious virus. Immune precipitation and polyacrylamide gel electrophoresis were used to study the synthesis of measles virion proteins in SSPE‐BIKEN‐infected cells. All of the virion proteins were detected in immune precipitated whole cell extracts. However, the hemagglutinin (HA) protein was not detected on the cell surface by lactoperoxidase iodination. These results suggest that the failure of the HA protein to insert into the cell membrane accounts for the block in the release of infectious virus. Radioactively labeled, noninfectious, virus‐like particles have been purified from the media of SSPE‐BIKEN‐infected cells. These particles contain virus nucleocapsid, nucleocapsid‐associated, and membrane proteins, but very little HA and hemolysin proteins.

Genetic complementation between SSPE‐BIKEN and a temperature‐sensitive mutant of measles virus was observed and suggests that the SSPE isolate defect is due to a mutation. Additional evidence of a mutation is provided by the detection of low frequency revertant progeny in SSPE‐BIKEN stocks. Our results support the hypothesis that genetic variants of measles virus are involved in the etiology of SSPE.
Purification of poliovirus by affinity chromatography
Authors: Brown Fred , Underwood Bryan O. , Fantes Karl H.
Published: March 2007

Poliovirus type 1 (Mahoney strain) has been purified by retention on a Sepharose 4B‐antibody column and elution with 3M K thiocyanate. The virus was recovered in excellent yield and its purity was as high as that achieved by detergent treatment followed by sucrose gradient centrifugation. The column could be re‐used and its capacity was sufficiently high to make it a useful method for the purification of milligram quantities of the virus.
Coronavirus infections of man associated with diseases other than the common cold
Authors: Riski Hellevi , Hovi Tapani
Published: March 2007

About 14,000 paired sera, from patients with various types of acute infectious diseases with suspected viral origin, were screened by complement fixation against a wide set of viral antigens, including coronavirus OC43. A significant change in OC43 antibodies was recorded in 33 cases and a constant high titre, defined as a titre occurring in the respective age group in less than 1 % of all sera examined, was found in 45 cases. On the basis of careful retrospective analysis of hospital case records it was concluded that in 28 cases with an increase of OC43 antibody litres, and in two with titre decrease, a disease could be associated with an acute coronavirus infection. In 16 cases the disease was dominated by respiratory symptoms. Eight of these patients, four children and four adults, had pneumonia. Three of the eight pneumonia patients had, however, another concomitant infection, too. Four patients had neurological symptoms, one had severe perimyocarditis, and in five cases fever was the only symptom recorded. Among the patients with a statistically significant high titre of OC43 antibodies, there were 14 cases where a suggestive association with a disease could be envisaged on the basis of hospital records. Five of these patients had pneumonia.

These results suggest that human coronaviruses, so far considered only as one group of causative agents of the common cold, may also be associated with other and more severe diseases in all age groups.
Viral hepatitis: report on a who informal consultation
Authors: McCollum Robert W. , Zuckerman Arie J. , Assaad F.
Published: March 2007

List of Participants: M.S. Balayan (USSR), F. Deinhardt (Federal Republic of Germany), R.J. Gerety (USA), I.D. Gust (Australia), J.E. Maynard (USA), R.W. McCollum (USA), O. Sobeslavsky (Czechoslovakia), and A.J. Zuckerman (UK).

Representatives from WHO Regions: J. Mwakalukwa (Tanzania) unable to attend, V.M. Villarejos (Costa Rica), F. Ala (Iran), K.M. Tin (Burma), and K. Nishioka (Japan).

Observers: P. Grob (Switzerland), and D. Trichopoulos (Greece) representing the International Agency for Research on Cancer.

WHO Secretariat: P. Bres (WHO Headquarters), and J. Bond WHO Regional Office for the Americas)
Development of serum and intestinal antibody response to rotavirus after naturally acquired rotavirus infection in man
Authors: Riepenhoff‐Talty Marie , Bogger‐Goren Sara , Li Philip , Carmody Patricia J. , Barrett Helen J. , Ogra Pearay L.
Published: March 2007

The temporal characteristics of the response of rotavirus specific IgM, IgG, IgA in serum and secretory antibody in feces to rotavirus were studied in 77 hospitalized patients with rotavirus induced gastroenteritis. The response in serum was characterized by the sequential appearance of rotavirus specific IgM, IgG, and IgA antibody. The IgM antibody appeared to be higher in the acute phase of the disease and was subsequently replaced by the IgG and IgA antibodies. However, the titers of IgG rotavirus antibody in convalescent specimens of serum were found to be statistically significantly lower in patients with severe or prolonged rotavirus infection than in specimens from subjects with mild or moderate disease.

Most fecal specimens collected during both the acute and convalescent phase of illness contained virus specific secretory IgA. Higher concentrations of antibody were measured in convalescent samples from patients with prolonged diarrhea and virus shedding. These observations suggest a possible relationship between the severity of rotavirus infection and the nature of systemic and secretory antibody response.
An assay for the detection of the dna genome of hepatitis b virus in serum
Authors: Berninger Mark , Hammer Marlene , Hoyer Bill , Gerin John L.
Published: March 2007

An assay based on nucleic acid hybridization detects and quantitates hepatitis B virus (HBV) DNA in particles present in serum. This assay allows rapid examination of multiple samples and is sensitive and reproducible; serum samples are treated with proteolytic enzyme and detergent and then extracted with phenol and chloroform. The deproteinized extracts which may contain HBV DNA are made alkaline to denature the DNA, neutralized, and bound to nitrocellulose filters in 3‐mm in diameter “spots” in a special 96‐well filtration apparatus. HBV DNA is detected by its ability to hybridize with 32P‐labeled DNA prepared from recombinant plasmids containing the complete HBV genome. After hybridization, the nitrocellulose is washed and autoradiographed; samples containing HBV produce spots on X‐ray film whose intensity (in the linear exposure range of the film) is proportional to the amount of HBV DNA in the serum sample. The assay is specific and sensitive, correlates with infectivity of sera titered in chimpanzees as well as biophysical parameters, and is in agreement with serological indicators of HBV presence.
Immunogenicity in chimpanzees of experimental hepatitis B vaccines prepared from intact hepatitis B virus, purified polypeptides, or polypeptide micelles
Authors: Tabor Edward , Howard Colin R. , Skelly Jacinta , Snoy Philip , Goudeau Alain , Zuckerman Arie J. , Gerety Robert J.
Published: March 2007

The immunogenicity of three experimental hepatitis B vaccines was evaluated in chimpanzees. Although no antibody to hepatitis B surface antigen (anti‐HBs) was detected in two chimpanzees that received an aqueous polypeptide vaccine subcutaneously, a strong anti‐HBs response was observed two and ten weeks, respectively, following challenge with hepatitis B virus. Inoculation of two additional chimpanzees with a micellar preparation of these polypeptides by the intravenous route resulted in anti‐HBs production in one of the chimpanzees. Two chimpanzees inoculated subcutaneously with an aqueous vaccine of formalin‐inactivated intact hepatitis B virus developed anti‐HBs in low titers, but the development of antibody to the hepatitis B core antigen following challenge inoculations suggested that subclinical HBV infections may have occurred despite prior vaccination.
Antibody response after application of a new live attenuated mumps vaccine (Pariorix®) measured by enzyme‐linked immunosorbent assay (ELISA)
Authors: Popow‐Kraupp Therese , Kunz Christian , Hofmann Hanns
Published: March 2007

Mumps virus specific antibody concentrations were determined by enzyme‐linked immunosorbent assay (ELISA), hemolysis‐in‐gel (HIG) test, and hemagglutination‐inhibition (HI) test in 17 adult volunteers before and after vaccination with a new live mumps vaccine, Pariorix®. The results of the present study indicate that the strain Urabe‐Am 9 of the mumps virus (Pariorix) induces antibodies in 100% of seronegative adults when measured by ELISA and in 70.6% and 64.7% in HIG and HI, respectively. ELISA is therefore a very sensitive and reliable method for the demonstration of sero‐conversion after vaccination. The vaccine was well tolerated and clinically acceptable in the group of adult volunteers.
Rapid detection of rotavirus in stool by latex agglutination: Comparison with radioimmunoassay and electron microscopy and clinical evaluation of the test
Authors: Haikala Olli J. , Leinonen Maija K. , Nurmi Tapio , Kokkonen Jorma O. , Mäntyjärvi Rauno , Sarkkinen Hannu K.
Published: March 2007

A latex agglutination test (LX) using antisera prepared against Nebraska calf diarrhea virus (NCDV) is described for the detection of rotavirus in stool of children with acute gastroenteritis. The test was compared with electron microscopy (EM) and radioimmunoassay (RIA) with 100 stools positive or negative for rotavirus. Out of 53 stools positive in RIA or EM, 49 were positive in LX and 4 were negative. Two specimens negative in EM and RIA were falsely positive in LX. The method was also tested in two clinical series with 115 stools from 101 children. Altogether 67/115 stools were positive in RIA, and 62/115 in LX. Out of 7 stools with contradictory results, 6 were negative in LX but positive in RIA, and 1 was positive in LX but negative in RIA. The results indicate that the LX is suitable for rapid screening of rotavirus gastroenteritis in clinical practice.
Rotavirus shedding by newborn children
Authors: Perez‐Schael Irene , Daoud Georgette , White Laura , Urbina Gidalia , Daoud Naimeh , Perez Mireya , Flores Jorge
Published: March 2007

We studied the shedding of rotavirus by newborn children in the nurseries of a large maternity hospital in Caracas, Venezuela, throughout the year 1982. Sixty‐two (57%) of 108 children examined shed the virus within the first few days of life. Four (6%) of the 62 children who shed rotavirus had diarrhea but only one of them required oral rehydration therapy. The rotavirus specimens were identified as subgroup 2 in an ELISA subgrouping assay that employs monoclonal antibodies. Analysis of the RNA extracted from 52 of the samples by electrophoresis revealed a similar migration pattern in all the specimens; their identity was confirmed by crosshybridization analyses which revealed a strong degree of genomic homology among the strains studied.
Faecal and pharyngeal shedding of rotavirus and rotavirus IgA in children with diarrhoea
Authors: Stals F. , Walther F. J. , Bruggeman C. A.
Published: March 2007

In 70 children 0–4 years of age with acute diarrhoea, the shedding of rotavirus and the excretion of rotavirus‐specific IgA antibody in the stools were examined throughout the period of clinical symptoms. Quantitative detection of rotavirus and IgA was performed by an ELISA technique. The maximal rotavirus shedding was found between the second and fifth day and the maximal excretion of IgA antibody about the seventh day, which marked the clinical recovery of most children. Throat swabs were examined for both virus particles and specific IgA antibody to try to document the respiratory spread of rotavirus infection. Rotavirus antigen could not be demonstrated in the throat swabs, but specific IgA antibody was detected at levels comparable to the faecal specimens obtained at clinical recovery. The observations indicate that the presence of rotavirus secretory IgA limits the duration of diarrhoea and plays a major role in the intestinal resistance to infection.
Detection of Norwalk virus in stools by enzyme immunoassay
Authors: Herrmann John E. , Nowak Nancy A. , Blacklow Neil R.
Published: March 2007

The development of a solid‐phase microtiter enzyme immunoassay (EIA) for detection of Norwalk virus antigen in stool samples is described. The EIA was compared with a previously developed radioimmunoassay (RIA) for detection of Norwalk virus antigen in stools obtained from 30 volunteers who received Norwalk virus. The EIA detected viral antigen in stools from 17 of the volunteers and the RIA detected viral antigen in 15. Seroconversion was a more sensitive indicator of infection in some patients. However, two samples from volunteers who were clinically ill but did not show seroconversion to Norwalk virus were positive for Norwalk virus antigen by both immunoassays. This indicates that antigen detection may be important for use in epidemiological studies. Neither of the immunoassays gave positive reactions for stools known to contain enteric adenovirus, rotavirus, or Hawaii virus, or in stools from patients with acute diarrhea of unknown cause. The stability of the EIA reagents and ease of use should provide a means for more extensive testing for Norwalk virus in outbreaks of gastroenteritis.