[Treatment plan and informed consent]

Since STI571, a BCR-ABL tyrosine kinase inhibitor, has made a great therapeutic advance in the management of CML, we have to reconsider the treatment protocol for chronic phase CML. Interferon-alpha (IFN-alpha) will be replaced with STI571 therapy. However, some patients are reported to become refractory to STI571, and it is unclear whether STI571 therapy alone may be sufficient to induce long-term survival in CML. There are also important progress in the field of allogeneic hematopoietic stem cell transplantation (SCT); i.e. minitransplant(non-myeloablative SCT) and cord blood stem cell transplantation. Currently, newly-diagnosed CML patients in chronic phase should be initially treated with STI571. If the patients are appropriate candidates for allogeneic SCT and have HLA-indentical sibling donors, allogeneic SCT should be conducted within one year. The other patients should also receive related or unrelated allogeneic SCT if Ph suppression is insufficient with STI571 therapy for several months. The patients who are not candidates for allogeneic SCT may be treated with IFN-alpha and/or Hydrea(or cytosine arabinoside) in addition to STI571 if they become refractory to STI571. Since each therapeutic modality has different risk and benefits, informed consent is very important to determine the treatment plan for individual patients.

Adeno-associated virus vector-mediated triple gene transfer of dopamine synthetic enzymes

OBJECTIVE

To explore triple gene transfer of dopamine synthetic enzymes with separate adeno-associated virus (AAV) vectors.

METHODS

The genes for dopamine synthetic enzymes, tyrosine hydroxylase (TH), aromatic L-amino acid decarboxylase (AADC), and GTP cyclohydrolase I (GCH, an enzyme critical for tetrahydrobiopterin synthesis) were contransduced into 293 cells with separate AAV vectors. Expressions of TH, AADC and GCH were detected by Western blot analysis. Intracellular dopamine level was assayed by high-performance liquid chromatography.

RESULTS

TH, AADC and GCH were effectively coexpressed in transduced cells with three separate AAV vectors, AAV-TH, AAV-AADC and AAV-GCH. Furthermore, the coexpression resulted in an effectively spontaneous dopamine production in cotransduced cells.

CONCLUSION

The triple transduction of TH, AADC and GCH genes with separate AAV vectors is effective, which might be important to gene therapy for Parkinson's disease.

Expression of the endoplasmic reticulum molecular chaperone (ORP150) rescues hippocampal neurons from glutamate toxicity

A series of events initiated by glutamate-receptor interaction perturbs cellular homeostasis resulting in elevation of intracellular free calcium and cell death. Cells subject to such environmental change express stress proteins, which contribute importantly to maintenance of metabolic homeostasis and viability. We show that an inducible chaperone present in endoplasmic reticulum (ER), the 150-kDa oxygen-regulated protein (ORP150), is expressed both in the human brain after seizure attack and in mouse hippocampus after kainate administration. Using mice heterozygous for ORP150 deficiency, exposure to excitatory stimuli caused hippocampal neurons to display exaggerated elevation of cytosolic calcium accompanied by activation of mu-calpain and cathepsin B, as well as increased vulnerability to glutamate-induced cell death in vitro and decreased survival to kainate in vivo. In contrast, targeted neuronal overexpression of ORP150 suppressed each of these events and enhanced neuronal and animal survival in parallel with diminished seizure intensity. Studies using cultured hippocampal neurons showed that ORP150 regulates cytosolic free calcium and activation of proteolytic pathways causing cell death in neurons subject to excitatory stress. Our data underscore a possible role for ER stress in glutamate toxicity and pinpoint a key ER chaperone, ORP150, which contributes to the stress response critical for neuronal survival.

Fanconi anemia protein, FANCA, associates with BRG1, a component of the human SWI/SNF complex

Fanconi anemia (FA) is a genetic disorder that predisposes to hematopoietic failure, birth defects and cancer. We identified an interaction between the FA protein, FANCA and brm-related gene 1 (BRG1) product. BRG1 is a subunit of the SWI/SNF complex, which remodels chromatin structure through a DNA-dependent ATPase activity. FANCA was demonstrated to associate with the endogenous SWI/SNF complex. We also found a significant increase in the molecular chaperone, glucose-regulated protein 94 (GRP94) among BRG1-associated factors isolated from a FANCA-mutant cell line, which was not seen in either a normal control cell line or the mutant line complemented by wild-type FANCA. Despite this specific difference, FANCA did not appear to be absolutely required for in vitro chromatin remodeling. Finally, we demonstrated co-localization in the nucleus between transfected FANCA and BRG1. The physiological action of FANCA on the SWI/SNF complex remains to be clarified, but our work suggests that FANCA may recruit the SWI/SNF complex to target genes, thereby enabling coupled nuclear functions such as transcription and DNA repair.

Recombinant adeno-associated virus vector-transduced vascular endothelial cells express the thrombomodulin transgene under the regulation of enhanced plasminogen activator inhibitor-1 promoter

We were able to facilitate plasminogen activator inhibitor 1 (PAI-1) promoter activity approximately by 14-fold using an enhancer element. This enhanced PAI-1 promoter has a strong basal activity, comparable to CAG promoter activity, and has a response similar to the PAI-1 promoter with respect to TGFbeta 1 and TNFalpha stimulation. The characteristics of the enhanced PAI-1 promoter are thought to be suited to timely and tissue-specific expression of anticoagulant molecules in the vascular cells. Thus, we developed recombinant adeno-associated virus (rAAV) vectors using the enhanced PAI-1 promoter and were successful in transducing vascular endothelial cells to express the thrombomodulin transgene under the regulation of the enhanced PAI-1 promoter in vitro. Thromobomodulin transgene expression driven by the enhanced PAI-1 promoter in rAAV vector-transduced cultured endothelial cells was between 600- and 1000-fold higher than constitutive thrombomodulin gene expression in cultured human umbilical vein endothelial cells and was up-regulated by TGFbeta1 and TNFalpha stimulation which may down-regulate endogenous thrombomodulin gene expression in endothelial cells. The brain vascular endothelial cells of Mongolian gerbils could also be transduced by the same rAAV vector in vivo. Transduction of endothelial cells by rAAV vectors to express enhanced PAI-1 promoter-driven transgenes may be a useful gene therapy approach for vascular diseases.

Development and characterization of an antisense-mediated prepackaging cell line for adeno-associated virus vector production

One of the limitations of recombinant adeno-associated virus (rAAV) vector systems for gene therapy applications has been the difficulty in producing the vector in sufficient quantity for adequate evaluation. Since the AAV Rep proteins are cytotoxic, it is not easy to establish stable cell lines that express them constitutively. We describe a novel 293-derived prepackaging cell line which constitutively expresses the antisense rep/cap driven by a loxP-flanked CMV promoter. This cell line was converted into a packaging cell line expressing Rep/Cap for rAAV vector production through adenovirus-mediated introduction of a Cre recombinase gene. Without the introduction of the Cre recombinase gene, the cell line was shown to produce neither Rep nor Cap. rAAV vector was produced (1 x 10(9) genome copies/3.5-cm dish) 4 days after the transduction with Cre-expression adenovirus vector together with transfection of AAV vector plasmid. We further showed that the addition of Cap-expression adenovirus vector caused a 10-fold increase in the yield of rAAV vector. This system is also capable of producing rAAV as a transfection-free system by using a small amount of rAAV instead of vector plasmid.

Sak serine-threonine kinase acts as an effector of Tec tyrosine kinase

The murine sak gene encodes a putative serine-threonine kinase which is homologous to the members of the Plk/Polo family. Although Sak protein is presumed to be involved in cell growth mechanism, efforts have failed to demonstrate its kinase activity. Little has been, therefore, elucidated how Sak is regulated and how Sak contributes to cell proliferation. Tec is a cytoplasmic protein-tyrosine kinase (PTK) which becomes activated by the stimulation of cytokine receptors, lymphocyte surface antigens, heterotrimeric G protein-linked receptors, and integrins. To clarify the in vivo function of Tec, we have tried to isolate the second messengers of Tec by using the yeast two-hybrid screening. One of such Tec-binding proteins turned out to be Sak. In human kidney 293 cells, Sak became tyrosine-phosphorylated by Tec, and the serine-threonine kinase activity of Sak was detected only under the presence of Tec, suggesting Sak to be an effector molecule of Tec. In addition, Tec activity efficiently protects Sak from the "PEST" sequence-dependent proteolysis. Internal deletion of the PEST sequences led to the stabilization of Sak proteins, and expression of these mutants acted suppressive to cell growth. Our data collectively supports a novel role of Sak acting in the PTK-mediated signaling pathway.

Expression of HGF/NK4 in ovarian cancer cells suppresses intraperitoneal dissemination and extends host survival

Peritoneal dissemination is the most frequent progression pathway of ovarian cancer and is therefore a key step to improve the prognosis. NK4, a large part of the alpha-chain of hepatocyte growth factor, is known to inhibit cancer cell migration. To characterize the function of NK4 and investigate its potential role in gene therapy of ovarian cancer, we introduced NK4 cDNA to an ovarian cancer cell line HRA and investigated its effects both in vitro and in vivo. HRA cells were transfected with either NK4 or luciferase-expression plasmids. After selection, NK4-expressing HRA cells (HRA/NK4) and the control cells (HRA/LUC) were obtained. NK4 was detected in the culture supernatant of HRA/NK4 by Western analysis. Migration capabilities of the cells were evaluated in vitro by scratch wound healing assay. The number of migrated cells was significantly smaller in the HRA/NK4 cultures than that in the control cultures (HRA or HRA/LUC). Also, the culture supernatant of HRA/NK4 significantly suppressed migration of control cells. This suppressive effect was observed when NK4-expressing cells were mixed with control cells at the ratio of 25% or more. In the in vivo experiments, HRA transfectants were injected intraperitoneally. The number of intraperitoneal tumors of HRA/NK4 was much smaller than that of control. In mice injected with HRA/NK4, ascites formation was suppressed and the survival was significantly prolonged. These findings suggest that NK4-mediated gene therapy can improve the prognosis of ovarian cancer by suppressing peritoneal dissemination.

Functions and ATP-binding responses of the twelve histidine residues in the TF1-ATPase beta subunit

The C2 proton signals of all (twelve) histidine residues of the TF1 beta subunit in the 1H-NMR spectrum have been identified and assigned by means of pH change experiments and site-directed substitution of histidines by glutamines. pH and ligand titration experiments were carried out for these signals. Furthermore, the ATPase activity of the reconstituted alpha3beta3gamma complex was examined for the twelve mutant beta subunits. Two of three conserved histidines, namely, His-119 and 324, were found to be important for expression of the ATPase activity. The former fixes the N-terminal domain to the central domain. His-324 is involved in the formation of the interface essential for the alpha3beta3gamma complex assembly. The other conserved residue, His-363, showed a very low pK(a), suggesting that it is involved in the tertiary structure formation. On the binding of a nucleotide, only the signals of His-173, 179, 200, and 324 shifted. These histidines are located in the hinge region, and its proximity, of the beta subunit. This observation provided further support for the conformational change of the beta monomer from the open to the closed form on the binding of a nucleotide proposed by us [Yagi et al. (1999) Biophys. J. 77, 2175-2183]. This conformational change should be one of the essential driving forces in the rotation of the alpha3beta3gamma complex.

Presence of Propionibacterium acnes in blood components

BACKGROUND

Sterility testing, as part of the QC of blood components at the Japanese Red Cross Aichi Blood Center between April 1998 and March 2000, showed that 10 of 5568 tested blood components (0.18%), all of which were RBC concentrates, were contaminated with bacteria. Nine isolates were Propionibacterium acnes and one was Staphylococcus capitis.

STUDY DESIGN AND METHODS

To investigate the molecular relatedness of eight available P. acnes isolates, 16S rRNA gene analysis and random amplified polymorphic DNA (RAPD) analysis were performed.

RESULTS

DNA sequencing analysis of the 16S rRNA gene showed that five isolates were identified as distinct strains and that three had identical sequences. RAPD analysis in the latter three isolates showed that two exhibited indistinguishable banding patterns that differed from that of the third isolate.

CONCLUSION

P. acnes was the most frequent contaminant of blood components, and six of eight isolates were molecularly unrelated. Further studies are necessary to investigate the precise mechanisms of contamination.

Reversible integration of the dominant negative retinoid receptor gene for ex vivo expansion of hematopoietic stem/progenitor cells

Since hematopoietic stem cells (HSCs) differentiate readily ex vivo resulting in the loss of self-renewal and engraftment abilities, the transient block of differentiation is essential to maintain those abilities during their ex vivo expansion culture. To this end, we developed a method of reversible integration of the dominant negative retinoic acid receptor (DN-RAR) gene, a differentiation-blocking gene, into cells utilizing the Cre/loxP-dependent gene recombination system. The murine immature hematopoietic 32D cells differentiate into mature neutrophils upon G-CSF treatment. However, 32D cells transduced with a retroviral vector expressing the DN-RAR gene put between two loxP sites continued to proliferate without showing differentiation even in the presence of G-CSF. After the cells were fully amplified, the cells were transduced with the Cre recombinase gene. The cells then restored the ability to differentiate into mature neutrophils upon G-CSF treatment. PCR analysis showed that the DN-RAR gene was efficiently removed from the genome by introduction of the Cre gene. This system may eventually be applicable to the ex vivo expansion of HSCs.

Distinguishable effects of presenilin-1 and APP717 mutations on amyloid plaque deposition

Both APP and PS-1 are causal genes for early-onset familial Alzheimer's disease (AD) and their mutation effects on cerebral Abeta deposition in the senile plaques were examined in human brains of 29 familial AD (23 PS-1, 6 APP) cases and 14 sporadic AD cases in terms of Abeta40 and Abeta42. Abeta isoform data were evaluated using repeated measures analysis of variance which adjusted for within-subject measurement variation and confounding effects of individual APP and PS-1 mutations, age at onset, duration of illness and APOE genotype. We observed that mutations in both APP and PS-1 were associated with a significant increase of Abeta42 in plaques as been documented previously. In comparison to sporadic AD cases, both APP717 and PS-1 mutation cases had an increased density (measured as the number of plaques/mm(2)) and area (%) of Abeta42 plaques. However, we found an unexpected differential effect of PS-1 but not APP717 mutation cases. At least some of PS-1 but not APP717 mutation cases had the significant increase of density and area of Abeta40-plaques as compared to sporadic AD independently of APOE genotype. Our results suggest that PS-1 mutations affect cerebral accumulation of Abeta burden in a different fashion from APP717 mutations in their familial AD brains.

Identification of myelodysplastic syndrome-specific genes by DNA microarray analysis with purified hematopoietic stem cell fraction

Myelodysplastic syndrome (MDS) is a slowly progressing hematologic malignancy associated with a poor outcome. Despite the relatively high incidence of MDS in the elderly, differentiation of MDS from de novo acute myeloid leukemia (AML) still remains problematic. Identification of genes expressed in an MDS-specific manner would allow the molecular diagnosis of MDS. Toward this goal, AC133 surface marker-positive hematopoietic stem cell (HSC)-like fractions have been collected from a variety of leukemias in a large-scale and long-term genomics project, referred to as "Blast Bank," and transcriptome of these purified blasts from the patients with MDS were then compared with those from AML through the use of oligonucleotide microarrays. A number of genes were shown to be expressed in a disease-specific manner either to MDS or AML. Among the former found was the gene encoding the protein Delta-like (Dlk) that is distantly related to the Delta-Notch family of signaling proteins. Because overexpression of Dlk may play a role in the pathogenesis of MDS, the disease specificity of Dlk expression was tested by a quantitative "real-time" polymerase chain reaction analysis. Examination of the Blast Bank samples from 22 patients with MDS, 31 with AML, and 8 with chronic myeloid leukemia confirmed the highly selective expression of the Dlk gene in the individuals with MDS. Dlk could be the first candidate molecule to differentiate MDS from AML. The proposal is made that microarray analysis with the Blast Bank samples is an efficient approach to extract transcriptome data of clinical relevance for a wide range of hematologic disorders.

Glutathione S-transferase Pi is a dopamine-inducible suppressor of dopamine-induced apoptosis in PC12 cells

The finding that the neurotransmitter dopamine induces apoptosis in neurons implies the existence of a cellular mechanism by which dopaminergic neurons protect themselves from dopamine-induced apoptosis. By profiling the expression of a number of genes in differentiating PC12 cells which exhibit elevated levels of dopamine biosynthesis, we found that expression of glutathione S-transferase class Pi (GSTp) mRNA was selectively up-regulated. Interestingly, dopamine added to the culture medium of PC12 cells also augmented their expression of GSTp mRNA. Suppression of GSTp expression by transfection of its antisense expression vector augmented dopamine-induced apoptosis of PC12 cells. Conversely, overexpression of GSTp made the resultant PC12 transfectants highly resistant to dopamine-induced apoptosis. Transfection of the antisense or sense GSTp expression vectors also resulted in corresponding augmentation or suppression of dopamine-induced activation of cell-associated Jun-N-terminal kinase (JNK), which has been suggested to mediate dopamine-induced apoptosis in neuronal cells. These results indicate that GSTp is a dopamine-inducible suppressor of dopamine-induced apoptosis in PC12 cells, and suggest that this activity is exerted through inhibition of JNK activity.

CAM-cytarabine, aclarubicin plus macrophage colony-stimulating factor in the treatment of acute myelogenous leukemia with trilineage dysplasia: usefulness of in vitro apoptosis in leukemic cells

A 67-year-old woman was treated for acute myelogenous leukemia with trilineage dysplasia (AML-TLD) by combination chemotherapy with cytarabine, aclarubicin plus macrophage colony-stimulating factor (M-CSF) (referred to as CAM therapy). Complete remission was achieved after two courses of CAM therapy. After coculture of her bone marrow mononuclear cells with M-CSF in vitro, differentiation of leukemic cells into macrophages with apoptotis was observed. This case confirms an earlier report that an effect of M-CSF inducible by differentiation with apoptotic phenomena, against human leukemic cells was shown both in vitro and in vivo when achieving complete remission.

Expression of the oxygen-regulated protein ORP150 accelerates wound healing by modulating intracellular VEGF transport

Expression of angiogenic factors such as VEGF under conditions of hypoxia or other kinds of cell stress contributes to neovascularization during wound healing. The inducible endoplasmic reticulum chaperone oxygen-regulated protein 150 (ORP150) is expressed in human wounds along with VEGF. Colocalization of these two molecules was observed in macrophages in the neovasculature, suggesting a role of ORP150 in the promotion of angiogenesis. Local administration of ORP150 sense adenovirus to wounds of diabetic mice, a treatment that efficiently targeted this gene product to the macrophages of wound beds, increased VEGF antigen in wounds and accelerated repair and neovascularization. In cultured human macrophages, inhibition of ORP150 expression caused retention of VEGF antigen within the endoplasmic reticulum (ER), while overexpression of ORP150 promoted the secretion of VEGF into hypoxic culture supernatants. Taken together, these data suggest an important role for ORP150 in the setting of impaired wound repair and identify a key, inducible chaperone-like molecule in the ER. This novel facet of the angiogenic response may be amenable to therapeutic manipulation.

A comprehensive analysis of loss of heterozygosity caused by hemizygous deletions in renal cell carcinoma using a subtraction library

Several new loci were identified by a comprehensive analysis of loss of heterozygosity (LOH) using a subtraction library between matched normal and renal cell carcinoma (RCC) tissues. A total of 187 clones from the library, with a complexity of 1x10(4), were mapped, and 44 clusters of the mapped loci were subjected to LOH analysis using microsatellite markers. A total of 27 loci, which exhibited frequencies of LOH of at least 10% among 44 tumors, mostly clear-cell RCC, included several loci that were reported previously, such as, the von Hippel-Lindau gene, adenomatous polyposis coli, and interferon regulatory factor-1, as well as new loci, at 5q32-q34, 6q21-q22, 8p12, and others. These loci exhibited LOH among 11.8-93.8% of tumors, and most, if not all, were derived from the sites of hemizygous deletions. The minimum regions of LOH of chromosomes 5, 6, and 8 were 9.0, 10.3, and 0.775 Mb, respectively. The average distance between the cloned fragments on the chromosomes was 2.2 Mb in 187 clones, indicating that the minimum LOH size expected from this subtraction analysis was roughly 50 kb. Therefore, the strategy described here provides comprehensive analysis of LOH sites, which were mostly caused by hemizygous deletions.

A novel recombinant adeno-associated virus vaccine induces a long-term humoral immune response to human immunodeficiency virus

Recombinant adeno-associated virus (AAV) has attracted tremendous interest as a promising vector for gene delivery. In this study we have developed an HIV-1 vaccine, using an AAV vector expressing HIV-1 env, tat, and rev genes (AAV-HIV vector). A single injection of the AAV-HIV vector induced strong production of HIV-1-specific serum IgG and fecal secretory IgA antibodies as well as MHC class I-restricted CTL activity in BALB/c mice. The titer of HIV-1-specific serum IgG remained stable for 10 months. When AAV-HIV vector was coadministered with AAV-IL2 vector, the HIV-specific cell-mediated immunity (CMI) was significantly enhanced. Boosting with AAV-HIV vector strongly enhanced the humoral response. Furthermore, the mouse antisera neutralized an HIV-1 homologous strain, and BALB/c mice immunized via the intranasal route with an AAV vector expressing the influenza virus hemagglutinin (HA) gene showed protective immunity against homologous influenza virus challenge. These results demonstrate that AAV-HIV vector immunization may provide a novel and promising HIV vaccination strategy.

Morphological and physiological restorations of hereditary form of dilated cardiomyopathy by somatic gene therapy

TO-2 strain hamsters with dilated cardiomyopathy, gene deletion of delta-sarcoglycan (SG) and no expression of alpha-, beta-, gamma-, and delta-SG proteins are useful for developing the potential gene therapy of intractable heart failure. We prepared recombinant adeno-associated virus vector including normal delta-SG gene driven by CMV promoter and intramurally administered in vivo. The transfected myocardium induced robust expression of both transcript and transgene for 2/3 period of the animal's life expectancy. Immunostaining demonstrated reexpression of not only delta-SG but also other three SGs in 40% cells in the transfected region and normalization of the diameter of transduced cardiomyocytes. Hemodynamic study revealed preferential amelioration of the diastolic indices (LVEDP, the dP/dt(min) and CVP). These results provide the first evidence that supplementation of a specific gene with efficient and sustained transfection capability restores the genetic, morphological, and functional deteriorations.

Antitumor effect of beta2-microglobulin in leukemic cell-bearing mice via apoptosis-inducing activity: activation of caspase-3 and nuclear factor-kappaB

We have reported previously that beta2-microglobulin (beta2m) induces apoptosis in leukemic cells in vitro, and that an interaction between beta2m and HLA class I antigen induces apoptosis. Here we examined whether beta2m can induce apoptosis in leukemic cells in vivo and whether it has an antitumor effect in tumor-bearing mice. Daily administration of 50 or 250 microg of beta2m induced apoptosis and an antitumor effect on K562 leukemia cell-bearing mice in the same manner as tumor necrosis factor-alpha. In tumor tissues in beta2m-treated mice, both caspase-3 and nuclear factor-kappaB (NF-kappaB) were stained more strongly than in control mice by anti-caspase-3 and anti-NF-kappaB p65/Rel A polyclonal antibodies. We also observed the in vivo immunological effects of beta2m on lymphoid and hematopoietic organs, such as thymus, bone marrow, Peyer's patches, liver, and spleen in normal mice. Using antibodies against caspase-3 and NF-kappaB, immunohistochemical staining showed that no specific tissues were damaged or stained in normal mice. We conclude that beta2m stimulates caspase-3 and NF-kappaB pathways to induce apoptosis, making it a useful approach to a new therapy for leukemia.

Urine-based enzyme-linked immunosorbent assay for the detection of Helicobacter pylori infection in children

OBJECTIVE

Serology and (13)C-urea breath test have been widely used as noninvasive tests to detect Helicobacter pylori infection. However, easier collection of samples and lower costs are desirable for diagnosis of the individual patient or for use in epidemiologic studies. Our aim was to study the diagnostic accuracy of a recently developed urine-based enzyme-linked immunosorbent assay (ELISA) kit for the detection of H pylori-specific immunoglobulin G (IgG) antibodies in children.

STUDY DESIGN

Specimens of serum and randomly voided urine were collected from 816 children (0-15 years old) and were analyzed using 2 serum-based ELISA kits and a urine-based ELISA kit, respectively. Based on results of serology, the sensitivity, specificity, and accuracy of the urine-based ELISA kit were evaluated. With regard to false-positive and false-negative results, urinary IgG concentrations and IgG/creatinine levels were studied.

RESULTS

Both serum-based ELISAs were positive in 41 children and were negative in 666, who were enrolled in this study. The remaining 109 children were excluded because of disagreement between the results of the 2 serum-based ELISAs, including indeterminate values. Overall sensitivity, specificity, and accuracy of urine-based ELISA test compared with serology were 85.4%, 95.5%, and 94.9%, respectively. On positivity rates, the urine-based ELISA was closely coincident with the serum-based ELISA in each age group. There was no correlation between antibody levels detected by urine-based ELISA and each serum-based ELISA. Urinary IgG concentrations and IgG/creatinine levels were significantly higher in false-positives and were lower in false-negatives than in true-positives plus true-negatives for serology. Most of those with false-positive results had trace to moderate proteinuria.

CONCLUSIONS

The urine-based ELISA is an alternative to serum-based ELISA for diagnosis of H pylori infection in children and should be suitable for large-scale epidemiologic studies concerning the organism. In children with proteinuria, results of the test should be interpreted with caution. It is possible that the urine-based ELISA method would be applicable to diagnosis of other infectious diseases.

Glutathione S-transferase Pi is a dopamine-inducible suppressor of dopamine-induced apoptosis in PC12 cells

The finding that the neurotransmitter dopamine induces apoptosis in neurons implies the existence of a cellular mechanism by which dopaminergic neurons protect themselves from dopamine-induced apoptosis. By profiling the expression of a number of genes in differentiating PC12 cells which exhibit elevated levels of dopamine biosynthesis, we found that expression of glutathione S-transferase class Pi (GSTp) mRNA was selectively up-regulated. Interestingly, dopamine added to the culture medium of PC12 cells also augmented their expression of GSTp mRNA. Suppression of GSTp expression by transfection of its antisense expression vector augmented dopamine-induced apoptosis of PC12 cells. Conversely, overexpression of GSTp made the resultant PC12 transfectants highly resistant to dopamine-induced apoptosis. Transfection of the antisense or sense GSTp expression vectors also resulted in corresponding augmentation or suppression of dopamine-induced activation of cell-associated Jun-N-terminal kinase (JNK), which has been suggested to mediate dopamine-induced apoptosis in neuronal cells. These results indicate that GSTp is a dopamine-inducible suppressor of dopamine-induced apoptosis in PC12 cells, and suggest that this activity is exerted through inhibition of JNK activity.

Glutathione S-transferase Pi is a dopamine-inducible suppressor of dopamine-induced apoptosis in PC12 cells

The finding that the neurotransmitter dopamine induces apoptosis in neurons implies the existence of a cellular mechanism by which dopaminergic neurons protect themselves from dopamine-induced apoptosis. By profiling the expression of a number of genes in differentiating PC12 cells which exhibit elevated levels of dopamine biosynthesis, we found that expression of glutathione S-transferase class Pi (GSTp) mRNA was selectively up-regulated. Interestingly, dopamine added to the culture medium of PC12 cells also augmented their expression of GSTp mRNA. Suppression of GSTp expression by transfection of its antisense expression vector augmented dopamine-induced apoptosis of PC12 cells. Conversely, overexpression of GSTp made the resultant PC12 transfectants highly resistant to dopamine-induced apoptosis. Transfection of the antisense or sense GSTp expression vectors also resulted in corresponding augmentation or suppression of dopamine-induced activation of cell-associated Jun-N-terminal kinase (JNK), which has been suggested to mediate dopamine-induced apoptosis in neuronal cells. These results indicate that GSTp is a dopamine-inducible suppressor of dopamine-induced apoptosis in PC12 cells, and suggest that this activity is exerted through inhibition of JNK activity.

Observation of rho/omega meson modification in nuclear matter

We measured the invariant mass spectra of electron-positron pairs in the target rapidity region of 12-GeV p+A reactions. We have observed a significant difference in the mass spectra below the omega meson between p+C and p+Cu interactions. This difference indicates that the spectral shape of mesons is modified at normal nuclear-matter density.

Gene transfer into nonhuman primate hematopoietic stem cells: implications for gene therapy

Hematopoietic stem cells (HSCs) are desirable targets for gene therapy because of their self-renewal and multilineage differentiation abilities. Retroviral vectors are extensively used for HSC gene therapy. However, the initial human trials of HSC gene marking and therapy showed that the gene transfer efficiency into human HSCs with retroviral vectors was very low in contrast to the much higher efficiency observed in murine experiments. The more quiescent nature of human HSCs and the lower density of retroviral receptors on them hindered the efficient gene transfer with retroviral vectors. Since nonhuman primates have marked similarity to humans in all aspects including the HSC biology, their models are considered to be important to evaluate and improve gene transfer into human HSCs. Using these models, clinically relevant levels (around 10% or even more) of gene-modified cells in peripheral blood have recently been achieved after gene transfer into HSCs and their autologous transplantation. This has been made possible by improving ex vivo transduction conditions such as introduction of Flt-3 ligand and specific fibronectin fragment (CH-296) into ex vivo culture during transduction, and the use of retroviral vectors pseudotyped with the gibbon ape leukemia virus or feline endogenous retrovirus envelope. Other strategies including the use of lentiviral vectors and in vivo selective expansion of gene-modified cells with the drug resistance gene or selective amplifier gene (also designated the molecular growth switch) are now being tested to further increase the fraction of gene-modified cells using nonhuman primate models. In addition to the high gene transfer efficiency, high-level and long-term expression of transgenes in human HSCs and their progeny is also required for effective HSC gene therapy. For this purpose, other backbones of retroviral vectors such as the murine stem cell virus and cis-DNA elements, such as the ss-globin locus control region and the chromatin insulator, also need to be tested in nonhuman primate models. Nonhuman primate studies will continue to provide an important framework for human HSC gene therapy. Well-designed nonhuman primate studies will also offer unique insights into the HSCs, immune system, and transplantation biology characteristic of large animals.

Regulation of tumor angiogenesis by oxygen-regulated protein 150, an inducible endoplasmic reticulum chaperone

Expression of angiogenic factors such as vascular endothelial growth factor (VEGF) under conditions of cell stress involves both transcriptional and translational events, as well as an important role for inducible endoplasmic reticulum (ER) chaperones. Coexpression of VEGF and 150-kDa oxygen-regulated protein (ORP), a novel ER chaperone, in human glioblastoma suggested a link between angiogenesis and ORP150. C6 glioma cells stably transfected with ORP150 antisense displayed selectively reduced ORP150 expression. Tumors raised after inoculation of immunocompromised mice with ORP150 antisense C6 glioma transfectants demonstrated an initial phase of growth comparable to wild-type C6 glioma cells which was followed by marked regression within 8 days. Decreased density of platelet/endothelial cell adhesion molecule 1-positive structures within the tumor bed was consistent with reduced angiogenesis in C6 gliomas expressing ORP150 antisense, compared with tumors derived from C6 cells overexpressing ORP150 sense or vector controls. In vitro, inhibition of ORP150 expression decreased release of VEGF into culture supernatants; in ORP150 antisense transfectants, VEGF accumulated intracellularly within the ER. These findings demonstrate a critical role for the inducible ER chaperone ORP150 in tumor-mediated angiogenesis via processing of VEGF, and, thus, highlight a new facet of angiogenic mechanisms amenable to therapeutic manipulation in tumors.

Forkhead family transcription factor FKHRL1 is expressed in human megakaryocytes. Regulation of cell cycling as a downstream molecule of thrombopoietin signaling

FKHRL1, a member of the Forkhead transcription factor family, is one of the downstream molecules of phosphatidylinositol 3-kinase-Akt. This molecule is a mammalian homolog of DAF-16, which plays an important role in the longevity of Caenorhabditis elegans. In this study we found that Akt and FKHRL1 proteins were detectable in highly purified normal human megakaryocytes and that these molecules were actually phosphorylated by thrombopoietin (TPO). To clarify the functional role of FKHRL1 in TPO signaling, we established a tetracycline-inducible system in the human TPO-dependent leukemia cell line UT-7/TPO. Induced expression of active FKHRL1 led to cell cycle arrest at G0/G1 phase in this cell line. These results suggest that FKHRL1 plays an important role in the cell cycle of megakaryocytic cells as one of the downstream target molecules of phosphatidylinositol 3-kinase-Akt, presumably mediated through the activation or inactivation of cell cycle-associated gene(s).

Targeting antigen-specific receptors on B lymphocytes to generate high yields of specific monoclonal antibodies directed against biologically active lower antigenic peptides within presenilin 1

We describe a targeting technique that selects antigen-specific receptors on B lymphocytes using antigen driven selective production of monoclonal antibodies which are directed against functional peptide sequences within the presenilin 1 molecule that is believed to be related to the early-onset of familial Alzheimer's disease. Three different peptide sequences of presenilin 1 were constructed, one including the region around the amino acid position 300, where the putative cleavage site exists and the other two present in the N- and C-terminal regions of that site. The efficiency in production of the desired monoclonal antibodies was at least 5-40-fold that obtained with the poly(ethylene glycol) (PEG)-mediated method. In addition, monoclonal antibodies directed against each of the peptide sequence displayed a high specificity for the corresponding peptide, in contrast to the lack of success using the PEG method. Also, the selection of surface immunoglobulin receptors on B lymphocytes by the peptides of interest was confirmed by immunofluorescent analysis. Here we demonstrate that targeting B lymphocytes results in the successful and efficient production of highly specific monoclonal antibodies against the lower antigenic peptide sequences.

An event-related fMRI study of syntactic and semantic violations

We used event-related functional magnetic resonance imaging to identify brain regions involved in syntactic and semantic processing. Healthy adult males read well-formed sentences randomly intermixed with sentences which either contained violations of syntactic structure or were semantically implausible. Reading anomalous sentences, as compared to well-formed sentences, yielded distinct patterns of activation for the two violation types. Syntactic violations elicited significantly greater activation than semantic violations primarily in superior frontal cortex. Semantically incongruent sentences elicited greater activation than syntactic violations in the left hippocampal and parahippocampal gyri, the angular gyri bilaterally, the right middle temporal gyrus, and the left inferior frontal sulcus. These results demonstrate that syntactic and semantic processing result in nonidentical patterns of activation, including greater frontal engagement during syntactic processing and larger increases in temporal and temporo-parietal regions during semantic analyses.

Expression of a novel RNA-splicing factor, RA301/Tra2beta, in vascular lesions and its role in smooth muscle cell proliferation

RA301/Tra2beta, a sequence-specific RNA-binding protein, was first cloned as a stress molecule in re-oxygenated astrocytes. In human vascular tissues, we have found enhanced RA301/Tra2beta expression in coronary artery with intimal thickening, and atherosclerotic aorta. Balloon injury to the rat carotid artery induced RA301/Tra2beta transcripts followed by expression of the antigen, which was detected in medial and neointimal vascular smooth muscle cells (VSMCs). In cultured VSMCs, hypoxia/re-oxygenation caused induction of RA301/Tra2beta and was accompanied by cell proliferation, both of which were blocked by the addition of either diphenyl iodonium, a NADPH oxidase inhibitor, PD98059, a mitogen-activated protein kinase kinase inhibitor, or antisense oligonucleotide for RA301/Tra2beta. Consistent with a link between RA301/Tra2beta and cell proliferation, platelet-derived growth factor also induced expression of RA301/Tra2beta in cultured VSMCS: These data suggest a possible role for RA301/Tra2beta in the regulation of VSMC proliferation, especially in the setting of hypoxia/re-oxygenation-induced cell stress.

Colon cancer with meningeal carcinomatosis and myelodysplastic syndrome in a patient who underwent intensive chemotherapy for acute myelogenous leukemia: a case report

A 59-year-old man was admitted to our hospital because of disturbance of consciousness and hyponatremia. The patient had suffered from acute myelogenous leukemia (AML) with 46,XY and received chemotherapy for 5 years. Meningeal carcinomatosis was diagnosed due to the detection of carcinoma cells in the cerebrospinal fluid (CSF). Hyponatremia was caused by syndrome of inappropriate secretion of anti-diuretic hormone (SIADH). Bone marrow examination revealed myelodysplastic syndrome (MDS) with deletion of the long arm of chromosome 7. Emergence of a new abnormal clone was suggested. The patient died from brain herniation. Post mortem examination showed adenocarcinoma in the colon. An association between chemotherapy and both colon cancer and MDS was suggested.

Long-term use of FK 506 in living related liver transplantation

FK 506 (Tacrolimus) was used with steroids to treat 61 pediatric patients who received living related partial liver transplantation. Fifty-two recipients survived and 9 died between 6 months and 3 years after transplantation. In the surviving patients, oral doses of Tacrolimus were tapered from 0.298 +/- 0.277 mg/kg daily at 1 month after transplantation to 0.078 +/- 0.054 at 24 months after transplantation. The 12 h trough levels of Tacrolimus were 12.6 +/- 7.1 ng/ml and 4.1 +/- 2.4 at 1 and 24 months after transplantation, respectively. The percentage of recipients free from steroids was 77%, 97%, and 94% at 6, 12, and 24 months after transplantation, respectively. Liver allograft rejection was encountered in seven recipients, five of whom were treated by steroid pulse therapy and a dose increase of Tacrolimus; the remaining two required OKT3. However, there was no episode of rejection that required retransplantation. Infectious complications encountered in 34 patients included 12 bacterial, 3 fungal, and 19 viral infections. Two recipients died one of fungal pneumonia and one of Epstein-Barr virus-associated lymphoproliferative disorder. Regarding adverse reactions of Tacrolimus, hypertension was observed in 28 patients, diabetes mellitus in 3, pancreatitis in 3, convulsion in 1, tremor in 12, itching in 5, and pigmentation in the oral mucosa in 2. Slightly increased values of creatinine were observed in most of the patients; however, an abnormal increase of serum of serum creatinine (> 1.0 mg/dl) was confined to the complicated cases. Improvement of somatic growth was observed in 21 patients (62%) and 13 (75%) at 12 and 24 months after transplantation, respectively. The long-term use of Tacrolimus is highly effective in terms of its immunosuppressive potential and reduced adverse reaction. Steady growth development can be expected in pediatric recipients free from steroids.

Delayed oxidation of intramitochondrial pyridine nucleotide oxido reduction state as compared with tissue oxygenation in human liver transplantation

Intra- and post-operative oxygenation of graft liver and subsequent oxidation of the intramitochondrial redox state of pyridine nucleotide were studied in liver transplantation from living related donors with the arterial ketone body ratio (AKBR), the ratio of oxidized flavoprotein to reduced pyridine nucleotide (FP/PN ratio), and oxygen saturation of hemoglobin in liver tissue (hepatic SO2). The subjects involved in this study consisted of 20 pediatric patients. Hepatic SO2 was measured by near-infrared tissue spectroscopy. FP/PN ratio was measured by two-dimensional fluorometric scanning. Tissue oxygenation was normalized at the end of the operation. By contrast, AKBR remained at a low value at the end of the operation. At 24 and 48 h after the operation, the AKBR values increased to near the control value, indicating that it took 24 h for the intramitochondrial redox state to be normalized. The FP/PN ratio also remained at a low value at the end of the operation as compared with the control value. In conclusion, the observed delay in oxidation of the intramitochondrial redox state as compared with tissue oxygenation indicated the transition of the redox state associated with the changes in the metabolic state, and suggested the important role of microcirculation in the normalization of the redox state.

Measurement of the B(e2) of (7)(lambda)Li and shrinkage of the hypernuclear size

We report on the first measurement of a hypernuclear gamma-transition probability. gamma rays emitted in the E2(5/2(+)-->1/2(+)) transition of (7)(Lambda)Li were detected by a large-acceptance germanium detector array (Hyperball), and the lifetime of the parent state ( 5/2(+)) was determined by the Doppler shift attenuation method. The obtained result, 5.8(+0.9)(-0.7)+/-0.7 ps, was then converted into the reduced transition probability [ B(E2)] to be B(E2;5/2(+)-->1/2(+)) = 3.6+/-0.5(+0.5)(-0.4) e(2) fm(4). Compared with the B(E2) of the corresponding E2(3(+)-->1(+)) transition in the 6Li nucleus, our result gives evidence that the size of the 6Li core in (7)(Lambda)Li is smaller than the 6Li nucleus in the free space.

Gene therapy of Parkinson's disease using adeno-associated virus (AAV) vectors

Parkinson's disease (PD) is characterized by the progressive loss of the dopaminergic neurons in the substantia nigra and a severe decrease in dopamine in the striatum. A promising approach to the gene therapy of PD is intrastriatal expression of dopamine-synthesizing enzymes [tyrosine hydroxylase (TH) and aromatic L-amino acid decarboxylase (AADC)]. The most appropriate gene-delivery vehicles for neurons are adeno-associated virus (AAV) vectors, which are derived from non-pathogenic virus. Therefore, TH and AADC genes were introduced into the striatum in the lesioned side using separate AAV vectors in parkinsonian rats, and the coexpression of TH and AADC resulted in better behavioral recovery compared with TH alone. Another strategy for gene therapy of PD is the protection of dopaminergic neurons in the substantia nigra using an AAV vector containing a glial cell line-derived neurotrophic factor (GDNF) gene. Combination of dopamine-supplement gene therapy and GDNF gene therapy would be a logical approach to the treatment of PD.

Successful resection of a liver metastasis from gastric leiomyoblastoma: report of a case

A 20-year-old woman was referred to our hospital for detailed investigation of a gastric submucosal tumor. A leiomyoma was preoperatively diagnosed and laparoscopic-assisted enucleation was performed. The resected tumor was 4 x 3 x 1.5 cm in size and postoperative histological examination identified it as a gastric leiomyoblastoma. Therefore, a secondary resection in the form of a distal gastrectomy was carried out. No tumor cells were found in the gastric specimen or in the lymph nodes; however, 5 months after the operation, an abdominal computed tomography scan revealed a recurrence in the liver, and she was readmitted for further examinations. The lesion was diagnosed as a single liver metastasis from the gastric leiomyoblastoma and successfully resected. The histopathological findings of the liver tumor resembled those of the primary gastric tumor. Her postoperative course was uneventful and she has been well, without any evidence of recurrence, to date. Only 12 other cases of leiomyoblastoma of the stomach with liver metastasis have been reported in Japan, all of which were associated with a very poor prognosis. Therefore, patients with this unusual disease entity should be carefully followed up after resection of the primary tumor.

Purification and characterization of homo- and hetero-dimeric acetate kinases from the sulfate-reducing bacterium Desulfovibrio vulgaris

Two distinct forms of acetate kinase were purified to homogeneity from a sulfate-reducing bacterium Desulfovibrio vulgaris Miyazaki F. The enzymes were separated from the soluble fraction of the cells on anion exchange columns. One acetate kinase (AK-I) was a homodimer (alpha(S)(2)) and the other (AK-II) was a heterodimer (alpha(S)alpha(L)). On SDS-PAGE, alpha(L) and alpha(S) subunits migrated as bands of 49.3 and 47.8 kDa, respectively, but they had an identical N-terminal amino acid sequence. A rapid HPLC method was developed to directly measure ADP and ATP in assay mixtures. Initial velocity data for AK-I and AK-II were collected by this method and analyzed based on a random sequential mechanism, assuming rapid equilibrium for the substrate binding steps. All kinetic parameters for both the forward acetyl phosphate formation and the reverse ATP formation catalyzed by AK-I and AK-II were successfully determined. The two enzymes showed similar kinetic properties in Mg(2+) requirement, pH-dependence and magnitude of kinetic parameters. These results suggest that two forms of acetate kinase are produced to finely regulate the enzyme function by post-translational modifications of a primary gene product in Desulfovibrio vulgaris.

ORP150 protects against hypoxia/ischemia-induced neuronal death

Oxygen-regulated protein 150 kD (ORP150) is a novel endoplasmic-reticulum-associated chaperone induced by hypoxia/ischemia. Although ORP150 was sparingly upregulated in neurons from human brain undergoing ischemic stress, there was robust induction in astrocytes. Cultured neurons overexpressing ORP150 were resistant to hypoxemic stress, whereas astrocytes with inhibited ORP150 expression were more vulnerable. Mice with targeted neuronal overexpression of ORP150 had smaller strokes compared with controls. Neurons with increased ORP150 demonstrated suppressed caspase-3-like activity and enhanced brain-derived neurotrophic factor (BDNF) under hypoxia signaling. These data indicate that ORP150 is an integral participant in ischemic cytoprotective pathways.

Apparent change of masking functions with compression-type digital hearing aid

Signal perception ability under conditions of a narrow band masker in subjects with hearing aids was examined using a theoretical model of the auditory nerve fibre (ANF) with a deteriorated tuning curve in addition to measurements of actual masking function in subjects wearing hearing aids. The results obtained indicate that the apparent masking function could be affected by the frequency-gain character as well as by the degree of compression. Usually, the compression-type of amplification with flat and/or high-frequency weighted characteristics improves not only the apparent thresholds but also the apparent masked thresholds under conditions of lower frequency masking. On the other hand, a low-frequency masker amplified by a higher gain with low-frequency weighted amplification could cause larger upward-masking effects on the signal perception of the higher frequency signal in some conditions. The present study may contribute to our understanding of the underlying mechanisms of the effects of different amplification by the aid.

Stimulation of GATA-2 as a mechanism of hydrogen peroxide suppression in hypoxia-induced erythropoietin gene expression

Hydrogen peroxide (H2O2) has previously been shown to inhibit the DNA binding activity of hypoxia inducible factor-1 (HIF-1), the accumulation of HIF-1alpha protein and erythropoietin (Epo) gene expression. Epo gene expression has been previously shown to be down-regulated through a GATA binding site at its promoter region. In this study, the effect of H2O2 on Epo gene expression under hypoxic conditions through a GATA transcription factor was investigated. Hypoxic induction was found to be inhibited upon the addition of H2O2, and this effect could be reversed through the addition of catalase. Hypoxic induction was found to be suppressed by co-transfection with a human GATA-2 cDNA expression plasmid. Transfection of Hep3B cells with a reporter gene bearing a mutation at the promoter GATA binding site was found to be only mildly affected by the addition of H2O2. Electrophoretic gel mobility shift assays (EMSAs), using the Epo promoter GATA site as a probe and the GATA-2 protein extracted from Hep3B cells, showed that addition of H2O2 enhanced the binding of GATA-2 while addition of catalase inhibited this binding. From these results, we conclude that H2O2 increases the binding activity of GATA-2 in a specific manner, thereby suppressing the activity of the Epo promoter and thus inhibiting Epo gene expression.

Gamma-rays enhance rAAV-mediated transgene expression and cytocidal effect of AAV-HSVtk/ganciclovir on cancer cells

Adeno-associated virus (AAV) vector has several unique properties suited for gene therapy applications. However, relatively low efficiency of transgene expression, which is mainly due to a limited second-strand synthesis from the single-stranded AAV genome, can be a problem in some applications that require potent gene expression such as antitumor applications. Recently, gamma-ray irradiation has been reported to enhance the second-strand synthesis of the AAV genome, and consequently transgene expression. We demonstrate here that an AAV vector harboring the herpes simplex virus type-1 thymidine kinase (HSVtk) is able to kill cancer cells more efficiently when used in combination with gamma-ray irradiation. A human maxillary sinus cancer cell line, NKO-1, was efficiently killed in combination with HSVtk transduction and ganciclovir (GCV), as expected. More importantly, gamma-ray irradiation of practical dosages augmented the cytocidal effect of the HSVtk/GCV system. Southern analysis indicated that gamma-rays enhanced the double-strand synthesis of the rAAV genome in NKO-1 cells. These findings suggest that the combination of rAAVtk/GCV suicide gene therapy with radiotherapy has synergistic effects in the treatment of cancers and may lead to a reduction of the potential toxicity of both rAAVtk/GCV and gamma-ray irradiation.

Downregulation of Bim, a proapoptotic relative of Bcl-2, is a pivotal step in cytokine-initiated survival signaling in murine hematopoietic progenitors

Two distinct signaling pathways regulate the survival of interleukin-3 (IL-3)-dependent hematopoietic progenitors. One originates from the membrane-proximal portion of the cytoplasmic domain of the IL-3 receptor (betac chain), which is shared by IL-3 and granulocyte-macrophage colony-stimulating factor and is involved in the regulation of Bcl-x(L) through activation of STAT5. The other pathway emanates from the distal region of the betac chain and overlaps with downstream signals from constitutively active Ras proteins. Although the latter pathway is indispensable for cell survival, its downstream targets remain largely undefined. Here we show that the expression of Bim, a member of the BH3-only subfamily of cell death activators, is downregulated by IL-3 signaling through either of two major Ras pathways: Raf/mitogen-activated protein kinase and the phosphatidylinositol 3-kinase/mammalian target of rapamycin. Akt/phosphokinase B does not appear to play a significant role in this regulatory cascade. Bim downregulation has important implications for cell survival, since enforced expression of this death activator at levels equivalent to those induced by cytokine withdrawal led to apoptosis even in the presence of IL-3. We conclude that Bim is a pivotal molecule in cytokine regulation of hematopoietic cell survival.

[Outcome of acute myelogenous leukemia in 41 patients treated with idarubicin: the prognosis of t(8;21) cases]

Idarubicin (IDR) has been used as the main drug in induction chemotherapy for acute myelogenous leukemia (AML) in the USA and Europe. Between May 1995 and October 1998, we treated 41 cases of fresh AML using IDR induction chemotherapy and analyzed the clinical course, remission rate, relapse rate and prognosis. The results obtained in these cases were similar to those in 26 cases treated with daunorubicin (DNR) in our hospital according to JALSG-AML92. The outcome in cases with abnormal chromosomes and cases showing relapse was very poor. In particular, all 5 t(8;21) cases in our series relapsed, suggesting that t(8;21) cannot be considered a favorable prognostic factor in cases treated with IDR-containing regimens. However, 3 of the 5 t(8;21) cases were positive for CD56, which itself is an unfavorable prognostic factor. Thus it is possible that CD56 was related to the poor outcome. Intensive post-remission induction chemotherapies will be required in order to obtain prolonged disease-free survival.

[Perspectives on postgenome medicine: Hematological diseases]

With advances in DNA chip(DNA microarray) technology, it has become possible to obtain genome-wide gene-expression profiling. This novel technology is now applied to the study of molecular pathogenesis, differential diagnosis, and prediction of prognosis in the field of hematological malignancies. Importantly, the list of informative genes includes new markers of diseases, which will be utilized for further investigation. As for clinical gene therapy, it has been criticized for promising too much and providing too little during the last 10 years. In 1999, however, the success of hematopoietic stem cell gene therapy was reported in the patients with X-SCID(X-linked severe combined immunodeficiency). The gene therapy of hemophilia B using AAV(adeno-associated virus) vector has also successfully started. Genetic manipulation will be applied to the treatment of various diseases with the development of novel technologies.

A functional role of mitogen-activated protein kinases, Erk1 and Erk2, in the differentiation of a human leukemia cell line, UT-7/GM: A possible key factor for cell fate determination toward erythroid and megakaryocytic lineages

The mitogen-activated protein (MAP) kinase cascade is a key regulator of mammalian cell proliferation and differentiation. In this study, we examined the roles of 2 members of the MAP kinase family, extracellular signal-regulated kinase 1 (Erk1) and Erk2, in erythropoietin (EPO)-induced erythroid differentiation and thrombopoietin (TPO)-induced megakaryocytic differentiation. UT-7/GM was used as a model system because this cell line is an erythroid/megakaryocytic bipotent cell line that can be induced to differentiate into the erythroid and megakaryocytic lineages by EPO and TPO, respectively. The kinetics of activation of Erk1 and Erk2 were examined during erythroid and megakaryocytic differentiation of UT-7/GM cells. EPO induced a transient activation of these kinases, peaking after 1 minute of stimulation and then declining quickly almost to the basal level. In contrast, TPO-induced activation of the kinases peaked at 10 minutes and persisted for up to 60 minutes, similar to the activation by granulocyte-macrophage colony-stimulating factor. The percentage of EPO-induced hemoglobin-positive cells was elevated by the addition of PD98059, a specific inhibitor of MEK1 (MAP kinase/ERK kinase 1). In contrast, PD98059 clearly reduced the amount of glycoprotein IIb/IIIa antigens induced by TPO on UT-7/GM cells. Thus, inactivation of Erk1 and Erk2 kinases promoted EPO-induced erythroid differentiation and suppressed TPO-induced megakaryocytic differentiation of UT-7/GM cells. In conclusion, the activation of Erk1 and Erk2 kinases may be a critical event in the determination of cell fate and the differentiation processes of the erythroid and megakaryocytic lineages.

Adeno-associated virus-mediated transfer of endothelial nitric oxide synthase gene inhibits protein synthesis of rat ventricular cardiomyocytes

We investigated whether nitric oxide (NO) synthase gene transfer could attenuate growth of cultured cardiac myocytes. First, we investigated the effects of exogenous NO and cGMP analog on protein synthesis of cultured neonatal rat cardiac myocytes. The NO donor 3-morpholino-sydnonimine-hydrochloride (SIN-1) and 8-bromo-cGMP caused concentration-dependent decreases in phenylephrine-stimulated incorporation of 3H-leucine into cardiac myocytes. We then transferred endothelial constitutive NO synthase (ecNOS) gene into cultured neonatal rat cardiac myocytes using adeno-associated virus (AAV) vectors. ecNOS gene transfer into cardiac myocytes induced 140 kD ecNOS protein expression and significantly increased cGMP contents of myocytes compared with control cells. ecNOS gene transfer inhibited 3H-leucine incorporation into cardiac myocytes in response to phenylephrine, which was significantly recovered in the presence of the NOS inhibitor N(G)-monomethyl-L-arginine acetate. These results indicate that endogenously generated NO by ecNOS gene transfer using AAV vectors inhibits the alpha-adrenergic agonist-induced cardiac protein synthesis at least partially via cGMP production.

Adeno-associated virus-mediated transfer of endothelial nitric oxide synthase gene reduces the vasoconstrictive response

BACKGROUND

Adeno-associated virus (AAV) has a number of attractive features for gene therapy including the ability to transduce nondividing cells and long term transgene expression.

OBJECTIVE

To investigate whether the endothelial constitutive nitric oxide synthase (ecNOS) gene can be efficiently introduced into rat aortic segments using AAV vectors and thereby modulate the vasoconstrictive response.

ANIMALS AND METHODS

Excised rat aortas were incubated with medium containing ecNOS-expressing AAV vectors (AAV-ecNOS). Expression of ecNOS in the aortic segments was evaluated by immunohistochemical staining. The isometric tension of the aortic segments transduced with AAV-ecNOS was measured.

RESULTS

Adventitial cells in rat aortic segments were efficiently transduced with AAV-ecNOS. The vasoconstrictive response induced by 30 mmol/L K(+) was enhanced in endothelium-denuded aortic segments compared with intact aortic segments. However, in endothelium-denuded aortic segments transduced with AAV-ecNOS, the enhancement of the vasoconstrictive response disappeared. This effect induced by ecNOS gene transfer was abolished in the presence of the nitric oxide synthase inhibitor N(G)-monomethyl-l-arginine acetate.

CONCLUSIONS

These results show that ecNOS gene transfer using AAV vectors abolishes the pathological enhancement of the vasoconstrictive response in endothelium-denuded aortic segments.

Cytomegalovirus pneumonitis, activated prothrombin time prolongation and subacute thyroiditis after unrelated allogeneic bone marrow transplantation

A 22-year-old female with acute myeloid leukemia (AML) in complete remission received a conditioning regimen containing antithymocyte globulin for an unrelated bone marrow transplant (BMT). After BMT, the patient suffered from cytomegalovirus (CMV) pneumonitis with markedly high levels of CMV antigenemia, activated prothrombin time (APTT) prolongation, and subacute thyroiditis. Recovery of CD4+ cells was delayed as long as 1 year after BMT. An association between these three episodes and viral infection due to the delayed recovery of CD4+ cells is suggested.