Adeno-associated Virus-mediated Ezh2 Knockdown Reduced the Increment of Newborn Neurons Induced by Forebrain Ischemia in Gerbil Dentate Gyrus

It is established that neurogenesis of dentate gyrus is increased after ischemic insult, although the regulatory mechanisms have not yet been elucidated. In this study, we focused on Ezh2 which suppresses gene expression through catalyzing trimethylation of lysine 27 of histone 3. Male gerbils were injected with adeno-associated virus (AAV) carrying shRNA targeting to Ezh2 into right dentate gyrus 2 weeks prior to forebrain ischemia. One week after ischemia, animals were injected with thymidine analogue to label proliferating cells. Three weeks after ischemia, animals were killed for histological analysis. AAV-mediated knockdown of Ezh2 significantly decreased the ischemia-induced increment of proliferating cells, and the proliferated cells after ischemia showed significantly longer migration from subgranular zone (SGZ), compared to the control group. Furthermore, the number of neural stem cells in SGZ significantly decreased after ischemia with Ezh2 knockdown group. Of note, Ezh2 knockdown did not affect the number of proliferating cells or the migration from SGZ in the non-ischemic condition. Our data showed that, specifically after ischemia, Ezh2 knockdown shifted the balance between self-renewal and differentiation toward differentiation in adult dentate gyrus.

Early distribution of18 F-labeled AAV9 vectors in the cerebrospinal fluid after intracerebroventricular or intracisternal magna infusion in non-human primates

BACKGROUND

The delivery of adeno-associated virus (AAV) vectors via the cerebrospinal fluid (CSF) has emerged as a valuable method for widespread transduction in the central nervous system. Although infusion into the cerebral ventricles is a common protocol in preclinical studies of small animals, the cisterna magna has been recognized as an alternative target for clinical studies because it can be reached in a less invasive manner using an intrathecal catheter via the subarachnoid space from a lumbar puncture.

METHODS

We evaluated the early distribution of fluorine-18-labeled AAV9 vectors infused into the lateral ventricle or cisterna magna of four non-human primates using positron emission tomography. The expression of the green fluorescent protein was immunohistochemically determined.

RESULTS

In both approaches, the labeled vectors diffused into the broad arachnoid space around the brain stem and cervical spinal cord within 30 min. Both infusion routes efficiently transduced neurons in the cervical spinal cord.

CONCLUSIONS

For gene therapy that primarily targets the cervical spinal cord and brainstem, such as amyotrophic lateral sclerosis, cisterna magna infusion would be a feasible and effective administration method.

P-152 The first morphokinetic map of human abnormal fertilisation

Study question

What are the similarities and differences between the morphokinetics of abnormal, one- (1PN) and three-pronuclear (3PN) and normal bi-pronuclear (2PN) fertilisation?

Summary answer

The morphokinetic analysis of 1PN/3PN fertilisation reveals novel aspects of abnormal early development.

What is known already

Assisted reproduction technology has allowed the observation of early human development. Initially assessed statically at a single time point, fertilization has revealed its complexity once observed by Time-Lapse Microscopy (TLM). Detailed morphokinetic analysis of fertilisation has been reported in the last few years, unveiling previously unknown cytoplasmic phenomena (e.g. the cytoplasmic wave and halo) and the importance of cell symmetry for embryo development. At present, abnormal fertilization remains neglected, despite potential for understanding the physiology and pathology of early human development.

Study design, size, duration

This retrospective study involved TLM observation of normally (2PN, n = 2,685) and abnormally (1PN, n = 41; 3PN, n = 127) fertilised oocytes generated in ICSI cycles. Oocyte retrievals were carried out after the clomiphene citrate-based minimal ovarian stimulation, between October 2019 and December 2020. Oocytes of patients with different diagnoses of infertility were included in the analysis, while cases involving cryopreserved gametes or surgically retrieved sperm were excluded.

Participants/materials, setting, methods

Microinjected oocytes were assessed by a combined TLM-culture system (Embryoscope). Oocytes not suitable for TLM assessment, due to excess of residual corona cells or inadequate orientation for correct observation, were not analysed. Phenomena, relevant to meiotic resumption, pronuclear dynamics, cytoplasmic/cortical modifications, cleavage pattern, and embryo quality, were annotated and compared between groups.

Main results and the role of chance

Second polar body (PBII) extrusion was observed in all 1PN- and in a majority of 3PN-zygotes (92.1%). A 0.3-hour delay in PBII extrusion was confirmed in 3PN-zygotes (P = 0.0439). In a significant proportion of 3PN-zygotes, a third (female) PN formed from reabsorption of the PBII. The cytoplasmic wave was observed not only in 2PN- and 3PN-, but also in 1PN-zygotes. The presence and position of cytoplasmic halo were comparable among the three classes of zygotes. However, the duration of the cytoplasmic halo was prolonged in 1PN-zygotes (P < 0.0001). PN juxtaposition immediately before PN breakdown was less frequent in 3PN- compared with 2PN-zygotes (P = 0.0159). Furthermore, asynchronous PN breakdown was increased in 3PN- compared with 2PN-zygotes (P = 0.0026). The PN area of 1PN- was larger than that of 2PN-zygotes; however, the PN area of 3PN-zygotes was smaller than that of 2PN-zygotes. In 1PN-zygotes, a developmental delay was observed starting from the disappearance of the cytoplasmic halo, reaching 9 hours at the time of cleavage (P < 0.0001). A higher incidence of abnormal cleavage (P = 0.0019) and blastomere fragmentation (P < 0.0001) was observed in 1PN-zygotes. Cleavage progression was increasingly affected especially in 1PN-zygotes, resulting in blastocyst formation rates of 70.2%, 12.2% and 53.5% in 2PN-, 1PN- and 3PN-zygotes, respectively (P < 0.0001).

Limitations, reasons for caution

The study data derive from treatments carried out in a single centre. The study findings therefore require independent verification from other research groups.

Wider implications of the findings

These observations suggest that 1PN and 3PN fertilisation follow the general pattern of normal fertilization. Crucially, they also shed light on diverse and previously undescribed phenomena - e.g. reabsorption of the PBII in 3PN zygotes - underpinning the origins of abnormal fertilization and potentially clinically relevant.

Trial registration number

not applicable

Global brain delivery of neuroligin 2 gene ameliorates seizures in a mouse model of epilepsy

BACKGROUND

Despite the increasing availability of effective drugs, around one-third of patients with epilepsy are still resistant to pharmacotherapy. Gene therapy has been suggested as a plausible approach to achieve seizure control, in particular for patients with focal epilepsy. Because seizures develop across wide spans of the brain in many forms of epilepsy, global delivery of the vectors is necessary to tackle such generalized seizures. Neuroligin 2 (NL2) is a postsynaptic cell adhesion molecule that induces or strengthens inhibitory synaptic function by specifically combining with neurexin 1.

METHODS

In the present study, we applied an adeno-associated virus (AAV) type 9 vector expressing NL2 to modulate neuronal excitability in broad areas of the brain in epileptic (EL) mice, a model of polygene epilepsy. We administered the AAV vector expressing Flag-tagged NL2 under the synapsin I promoter (AAV-NL2) via cardiac injection 6 weeks after birth.

RESULTS

Significant reductions in the duration, strength and frequency of seizure were observed during a 14-week observation period in NL2-treated EL mice compared to untreated or AAV-green fluorescent protein-treated EL mice. No behavioral abnormality was observed in NL2-treated EL mice in an open-field test. Immunohistochemical examination at 14 weeks after AAV-NL2 injection revealed the expression of exogenous NL2 in broad areas of the brain, including the hippocampus and, in these areas, NL2 co-localized with postsynaptic inhibitory molecule gephyrin.

CONCLUSIONS

Global brain delivery of NL2 by systemic administration of AAV vector may provide a non-invasive therapeutic approach for generalized epilepsy.

Focusing and spin polarization of atomic hydrogen beam

We have developed a spin-polarized-hydrogen beam with a hexapole magnet. By combining the beam chopper and pulsed laser ionization detection, the time-of-flight of the hydrogen beam was measured, and the dependence of the beam profile on the velocity was acquired, which was consistent with the beam trajectory simulations. The spin polarization of the beam was analyzed by using the Stern-Gerlach-type magnet in combination with the spatial scan of the detection laser. The spin polarization was about 95% at a focusing condition due to the hexapole magnet. The polarization was, on the other hand, reduced to about 70% for the beam at higher velocities, which is consistent with simulation results.

Higher Transduction Efficiency of AAV5 to Neural Stem Cells and Immature Neurons in Gerbil Dentate Gyrus Compared to AAV2 and rh10

The safety and high efficiency of adeno-associated virus (AAV) vectors has facilitated their wide scale use to deliver therapeutic genes for experimental and clinical purposes in diseases affecting the central nervous system (CNS). AAV1, 2, 5, 8, 9, and rh10 are the most commonly used serotypes for CNS applications. Most AAVs are known to transduce genes predominantly into neurons. However, the precise tropism of AAVs in the dentate gyrus (DG), the region where persistent neurogenesis occurs in the adult brain, is not fully understood. We stereotaxically injected 1.5 × 10¹⁰ viral genomes of AAV2, 5, or rh10 carrying green fluorescent protein (GFP) into the right side of gerbil hippocampus, and performed immunofluorescent analysis using differentiation stage-specific markers one week after injection. We found that AAV5 showed a significantly larger number of double positive cells for GFP and Sox2 in the DG, compared to the AAV2 and rh10 groups. On the other hand, AAVrh10 presented a substantially larger number of double positive cells for GFP and NeuN in the DG, compared to AAV2 and AAV5. Our findings indicated that AAV5 showed high transduction efficiency to neural stem cells and precursor cells, while AAVrh10 showed much higher efficiency to mature neurons in the DG.

Insufficient lipid lowering therapy could not bring favorable prognostic effect in high risk patients who were functionally deferred percutaneous coronary intervention

Introduction

Deferral of percutaneous coronary intervention (PCI) of a functionally insignificant stenosis is associated with favorable long-term prognoses. However, previous reports revealed that patients with fractional flow reserve (FFR) 0.81–0.85 had higher cardiovascular adverse event rates than those with FFR >0.85. Numbers of large clinical trials established the lower, the better strategy for low-density lipoprotein cholesterol (LDL-C) management for patients after PCI. However, in the real clinical practice, the achievement rate of target LDL-C is often insufficient in patients with atherosclerotic risk factors who were functionally deferred PCI.

Purpose

We aimed to examine optimal LDL-C management for patients with intermediate coronary stenosis deferred PCI by FFR measurement.

Methods

This observational study included 293 consecutive patients with coronary stenosis deferred PCI due to greater FFR than 0.80. We separately analyzed 90 patients with 0.81–0.85 of FFR and 203 patients with >0.85. Patients in each group were further classified into 2 groups based on LDL-C level at one year after FFR measurement; the Lower LDL-C group (<100 mg/dL) and the Higher LDL-C group (>100 mg/dL). The primary endpoint was major adverse cardiovascular and cerebrovascular events (MACCE) including death, non-fatal myocardial infarction, ischemic stroke, heart failure hospitalization and unplanned revascularization.

Results

Patients with FFR 0.81–0.85 had a significantly higher MACCE rate than those with FFR >0.85 (hazard ratio (HR): 1.77, 95% confidence interval (CI): 1.02–3.07, p=0.043). In patients with FFR 0.81–0.85, the Lower LDL-C group (n-=53) had a significantly lower rate of the primary endpoint than the Higher LDL-C group (HR: 0.41, 95% CI: 0.18–0.97, Log-rank p=0.036, Figure A). Whereas, there was no significant difference in the event rate between 2 groups in patients with FFR >0.85 (Log-rank p=0.42, Figure B).

Conclusion

Uncontrolled LDL-C level was associated with higher MACCE rate in patients who were deferred PCI due to FFR 0.81–0.85. These results suggested that even in patients who were deferred PCI, those with coronary artery stenosis of lower FFR value should receive strict LDL-C lowering therapy with close monitoring.

Figure 1

Funding Acknowledgement

Type of funding source: None

Statins bring the prognostic impact only in peripheral artery disease patients with elevated c-reactive proteins -subanalysis from multicenter registry-

Introduction

Recent trials demonstrated favorable effects of statins on the clinical prognosis, partly through anti-inflammatory properties, in patients with coronary artery disease. However, this favorable effect has not been fully verified in patients with peripheral arterial disease (PAD). We hypothesized that statins exert different prognostic effects depending on the degrees of inflammation at the time of endovascular therapy (EVT).

Methods

This study is a subanalysis from the Toma-Code Registry that is a Japanese prospective cohort of 2,321 consecutive patients with PAD treated by endovascular therapy in hospitals from 2014 to 2016. After the exclusion of patients without information of C-reactive protein (CRP) at the time of index EVT, 2,039 patients including 1,039 statin users and 1,000 statin non-users were ultimately analyzed. The patient enrolled were divided into 4 categories depending on CRP level at the time of EVT; Low-CRP (<0.1 mg/dL), Intermediate-low-CRP (0.1–0.3 mg/dL), Intermediate-High-CRP (0.3–1.0 mg/dL), and High-CRP (>1.0 mg/dL). A composite of death, stroke, myocardial infarction, and major amputation as the primary endpoint of this study was compared between statin users and non-users in each CRP category.

Results

The composite endpoint occurred in 255 patients during the observation period. Overall, statin users had a significantly lower event rate than non-users (Log-rank test: P<0.001). However, there were no significant difference in the event rates between statin users and non-users in the Low-, and Intermediate-Low-CRP categories. Only in the Intermediate-High- and the High-CRP categories, statin users showed a significantly lower event rates than non-users (P=0.02 and P=0.008, respectively, Figures). Additionally, multivariate Cox regression analysis in the High-CRP group revealed that statin use was independently associated with the primary endpoint (adjusted hazard ratio: 0.67 [95% confidence interval: 0.45–0.99]), even after the adjustment of covariants.

Conclusion

Statins may exert a favorable prognostic effect in PAD patients with highly elevated CRP, but not in those with low to moderate CRP level.

Event free survival

Funding Acknowledgement

Type of funding source: None

P5616Risk stratification of cardiovascular events among patients with functionally non-significant coronary stenosis

Introduction

Deferral of percutaneous coronary intervention (PCI) of a functionally non-significant stenosis is associated with a favorable long-term clinical prognosis. However, to date, there has been limited evidence to stratify the risk for the development of cardiovascular (CV) adverse events in patients who were deferred of PCI due to a greater fractional flow reserve (FFR) than 0.80 at the target lesion.

Purpose

We aimed to stratify the risk of CV events in patients with functionally significant and non-significant coronary stenosis.

Methods

This observational study included 458 patients who were proven angiographically intermediate coronary stenoses and were measured FFR, of whom 298 deferred patients with FFR>0.80 and 160 intervened patients with FFR<0.80. The primary endpoint was the incidence of major adverse cardiac and cerebrovascular events (MACCE) including any death, non-fatal myocardial infarction, hospitalization due to heart failure, ischemic stroke and any unplanned revascularization. ROC curve for MACCE indicated the cut-off point of FFR as 0.85 and 0.76 in deferred patients and intervened patients, respectively.

Results

During the observation period, 27 MACCE (9.1%) in the Deferred group, and 33 MACCE (20.6%) in Intervened group were occurred. Kaplan-Meier curves showed a higher MACCE rate in the Intervened group than Deferred group (hazard ratio (HR): 2.19, 95% confidence interval (CI): 1.29–3.71, Figure A). However, even among patients in the Deferred group, the population with “intermediate” FFR (0.81–0.85) had a significantly higher MACCE rate than those with higher FFR (>0.85) (HR 2.55, 95% CI 1.14–5.69, Figure B). This rate was comparable to that of the Intervened group at the remote phase (at 4-year: 32.0% vs. 35.8%). Conversely, in the Intervened group, there was no statistically significant difference in MACCE rate between patients with higher FFR (0.76–0.80) and those with lower FFR (<0.76) (Log-rank: p=0.21, Figure C).

Conclusion

The population with relatively low FFR in patients who were deferred PCI by FFR>0.80 had comparable MACCE rate to patients with FFR<0.80. Close observation after the FFR evaluation should be considered in those population.

Hippocampal GAD67 Transduction Using rAAV8 Regulates Epileptogenesis in EL Mice

Gene therapy has been employed as a therapeutic approach for intractable focal epilepsies. Considering the potential of focal GABAergic neuromodulation in regulating epileptogenesis, the GABA-producing enzyme, γ-aminobutyric acid decarboxylase 67 (GAD67), is highly suitable for epilepsy therapy. The EL/Suz (EL) mouse is a model of multifactorial temporal lobe epilepsy. In the present study, we examined focal gene transduction in epileptic EL mice using recombinant adeno-associated virus serotype 8 (rAAV8) expressing human GAD67 to enhance GABA-mediated neural inhibition. Eight-week-old mice were bilaterally injected with rAAV8-GFP or rAAV8-GAD67 in the hippocampal CA3 region. After four weeks, the GAD67-transduced EL mice, but not the rAAV-GFP-treated EL mice, exhibited a significant reduction in seizure generation. The GAD67-mediated depression became stable after 14 weeks. The excitability of the CA3 region was markedly reduced in the GAD67-transduced EL mice, consistent with the results of the Ca²⁺ imaging using hippocampal slices. In addition, downregulation of c-Fos expression was observed in GAD67-transduced hippocampi. Our findings showed that rAAV8-GAD67 induced significant changes in the GABAergic system in the EL hippocampus. Thus, rAAV8-mediated GAD67 gene transfer is a promising therapeutic strategy for the treatment of epilepsies.

Efficient transduction of adeno-associated virus vectors into gerbil hippocampus with an appropriate combination of viral capsids and promoters

Adeno-associated virus (AAV) is an ideal vector for gene transduction into the central nervous system because of its safety and efficiency. While it is currently widely used for clinical trials and is expected to become more widespread, the appropriate combination of viral serotypes and promoters have not been fully investigated. In this study, we compared the transduced gene expression of AAVrh10 to AAV5 in gerbil hippocampus using three different promoters, including cytomegalovirus (CMV), chicken β-actin promoter with the CMV immediate-early enhancer (CAG), and the Synapsin 1 (Syn1) promoter. Four-week-old male gerbils underwent stereotaxic injection with 1 × 10¹⁰ viral genome of AAV carrying green fluorescent protein (GFP). Quantification of the GFP-positive areas 3 weeks after injection showed that AAVrh10-CMV and AAVrh10-CAG were the most efficient (p < 0.001, compared with the control) and AAVrh10-Syn1 and AAV5-CMV were the next most efficient (p < 0.05, compared with the control). On the other hand, AAV5-Syn1 showed little expression, which was only observed at the injected site. In conclusion, we should note that some combinations of viral capsids and promoters can result in failure of gene delivery, while most of them will work appropriately in the transgene expression in the brain.

Environmental enrichment enhances autophagy signaling in the rat hippocampus

The findings that antidepressive treatments increase hippocampal neurotrophins have led researchers to emphasize the importance of neurogenesis, formation of new dendrites, and survival of neurons in the brain. However, it is difficult to maintain neural plasticity just by enriching the environment to facilitate formation of new networks. Neural plasticity also requires a degradation process that clears off unnecessary and undesirable components. We have recently reported an increase in autophagy signaling (wherein the cell digests components of itself) that has the potential of enhancing neuronal and synaptic plasticity after multiple sessions of electroconvulsive seizure treatment. The present study revealed an increase in autophagy signaling in the rat hippocampus following 2 weeks of environmental enrichment (EE), a procedure known to elicit antidepressive and anxiolytic behavioral changes in various animal paradigms. Western blot analysis showed an increase in hippocampal expression of microtubule-associated protein light chain 3-II (LC3-II), which is lipidated from LC3-I, in rats in the EE group. The effectiveness of the 2-week EE housing condition was validated by anxiolytic effects observed in the elevated plus maze test, enhanced habituation in the open field test, and elevation of hippocampal brain-derived neurotrophic factor expression. In addition, we showed that the EE housing condition ameliorated numbing/avoidance behaviors, but not hypervigilant behaviors, in an animal model of post-traumatic stress disorder (PTSD). This is the first report to show that EE can increase autophagy signaling and improve numbing/avoidance behaviors in an animal model of PTSD.

Electroconvulsive seizures enhance autophagy signaling in rat hippocampus

The putative antidepressive mechanisms of a series of electroconvulsive seizures (ECS) are the following: 1) downregulation of monoaminergic receptor expression in several brain regions, 2) upregulation of the expression of brain-derived neurotrophic factor (BDNF), and 3) increased neurogenesis in the hippocampus. In this study, we used Western blot techniques to present another mechanism in which ECS enhances the autophagy signaling that is involved in the machinery related to synaptic and neural plasticity. Antibodies for conjugated Atg5-Atg12 (58kD) and cleaved light chain protein 3-II (LC3-II; 14 kD) were used to detect autophagy signals. An antibody for cleaved caspase-3 (17 kD) was used to detect alterations in apoptotic signals. Mature BDNF (14kD) expression in the hippocampus was evaluated in order to qualify the effectiveness of the ECS or stress-loading treatment. While significantly increased autophagy signals and no increases in apoptotic signals were detected in the ECS-treated rat hippocampus, the reverse (increased apoptotic signals and no altered autophagy signals) was observed in stressed rat hippocampus. No neuronal cell loss but new mossy fiber sprouting has been reported to accompany multiple ECS treatments, and recent studies have revealed that autophagy processes regulate the number of specific neurotransmitter receptors and the plasticity of synaptic components. The present study illustrated the neuroplastic and neurotrophic profiles of ECS and the neurotoxic impact of severe stress loading on hippocampal regions. This is the first report to demonstrate increased autophagy signals in ECS-treated rat hippocampus and no alterations in autophagy signals in stress-loaded rat hippocampus.

Rescue of amyotrophic lateral sclerosis phenotype in a mouse model by intravenous AAV9-ADAR2 delivery to motor neurons

Amyotrophic lateral sclerosis (ALS) is the most common adult-onset motor neuron disease, and the lack of effective therapy results in inevitable death within a few years of onset. Failure of GluA2 RNA editing resulting from downregulation of the RNA-editing enzyme adenosine deaminase acting on RNA 2 (ADAR2) occurs in the majority of ALS cases and causes the death of motor neurons via a Ca²⁺-permeable AMPA receptor-mediated mechanism. Here, we explored the possibility of gene therapy for ALS by upregulating ADAR2 in mouse motor neurons using an adeno-associated virus serotype 9 (AAV9) vector that provides gene delivery to a wide array of central neurons after peripheral administration. A single intravenous injection of AAV9-ADAR2 in conditional ADAR2 knockout mice (AR2), which comprise a mechanistic mouse model of sporadic ALS, caused expression of exogenous ADAR2 in the central neurons and effectively prevented progressive motor dysfunction. Notably, AAV9-ADAR2 rescued the motor neurons of AR2 mice from death by normalizing TDP-43 expression. This AAV9-mediated ADAR2 gene delivery may therefore enable the development of a gene therapy for ALS.

Deficiency of neural recognition molecule NB-2 affects the development of glutamatergic auditory pathways from the ventral cochlear nucleus to the superior olivary complex in mouse

Neural recognition molecule NB-2/contactin 5 is expressed transiently during the first postnatal week in glutamatergic neurons of the central auditory system. Here, we investigated the effect of NB-2 deficiency on the auditory brainstem in mouse. While almost all principal neurons are wrapped with the calyces of Held in the medial nucleus of the trapezoid body (MNTB) in wild type, 8% of principal neurons in NB-2 knockout (KO) mice lack the calyces of Held at postnatal day (P) 6. At P10 and P15, apoptotic principal neurons were detected in NB-2 KO mice, but not in wild type. Apoptotic cells were also increased in the ventral cochlear nucleus (VCN) of NB-2 KO mice, which contains bushy neurons projecting to the MNTB and the lateral superior olive (LSO). At the age of 1 month, the number of principal neurons in the MNTB and of glutamatergic synapses in the LSO was reduced in NB-2 KO mice. Finally, interpeak latencies for auditory brainstem response waves II-III and III-IV were significantly increased in NB-2 KO mice. Together, these findings suggest that NB-2 deficiency causes a deficit in synapse formation and then induces apoptosis in MNTB and VCN neurons, affecting auditory brainstem function.

The cardiac pacemaker-specific channel Hcn4 is a direct transcriptional target of MEF2

AIMS

Hcn4, which encodes the hyperpolarization-activated, cyclic nucleotide-sensitive channel (I(h)), is a well-established marker of the cardiac sino-atrial node. We aimed to identify cis-elements in the genomic locus of the Hcn4 gene that regulate the transcription of Hcn4.

METHODS AND RESULTS

We screened evolutionarily conserved non-coding sequences (CNSs) that are often involved in the regulation of gene expression. The VISTA Enhancer Browser identified 16 regions, termed CNS 1-16, within the Hcn4 locus. Using the luciferase reporter assay in primary neonatal rat cardiomyocytes, we found that CNS13 conferred a prominent enhancer activity (more than 30-fold) on the Hcn4 promoter. Subsequent mutation analysis revealed that the Hcn4 enhancer function was dependent on myocyte enhancer factor-2 (MEF2) and activator protein-1 (AP1) binding sequences located in CNS13. Electrophoretic mobility shift assay and chromatin immunoprecipitation confirmed that MEF2 and AP1 proteins bound CNS13. Furthermore, overexpression of a dominant negative MEF2 mutant inhibited the enhancer activity of CNS13, decreased Hcn4 mRNA expression and also decreased the amplitude of I(h) current in myocytes isolated from the inflow tract of embryonic heart.

CONCLUSION

These results suggest that the novel enhancer CNS13 and MEF2 may play a critical role in the transcription of Hcn4 in the heart.

Preferential localization of neural cell recognition molecule NB-2 in developing glutamatergic neurons in the rat auditory brainstem

NB-2 is a neuronal cell recognition molecule that is preferentially expressed in auditory pathways. Mice deficient in the NB-2 gene exhibit aberrant responses to acoustic stimuli. Here we examined the expression and localization of NB-2 in the auditory brainstem during development in the rat. NB-2 was strongly expressed in the ventral cochlear nucleus (VCN), ventral acoustic stria, lateral and medial superior olivary complex (SOC), superior paraolivary nucleus, medial nucleus of the trapezoid body (MNTB), ventrolateral lemniscus, and central nucleus of the inferior colliculus (CIC). In the VCN and CIC, NB-2 was expressed in the regions that are known to respond to high frequencies. In situ hybridization combined with immunohistochemistry suggested that NB-2 is expressed only in neurons. NB-2 was colocalized with glutamatergic elements in the neuropil and the calyces of Held but not with glycinergic or GABAergic elements. NB-2 expression in the SOC was first detected at embryonic day (E)19, reached a maximum level at postnatal day (P)7, and declined thereafter. Immunolabeling with VGLUT1 and VGLUT2, markers for mature and premature glutamatergic synapses, respectively, in combination with NB-2 immunolabeling revealed that NB-2 is expressed at glutamatergic synapses. Collectively, our findings suggest that NB-2 plays a key role in maturation of glutamatergic synapses in the brainstem during the final stages of auditory development.

Examination of bovine lactoferrin binding to bifidobacteria

In the present study, lactoferrin binding to bifidobacteria and detection of lactoferrin-binding protein in membrane fractions of several bifidobacteria have been demonstrated. This is the first report showing the binding of bovine lactoferrin to four Bifidobacterium spp. (B. infantis, B. breve, B. bifidum, B. longum) incubated with biotinylated lactoferrin and fluorescein conjugated-avidin and observed under an inverted confocal laser scanning microscope. Fluorescence staining showed lactoferrin binding at the pole of the bacterial cells. A lactoferrin-binding protein with a molecular weight of approximately 67 kDa was also detected in the membrane fraction of Bifidobacterium spp. by far western blotting technique using biotinylated lactoferrin and horseradish peroxidase-conjugated streptavidin. Based on the results of this and previously reported studies, we suggest that binding of lactoferrin to Bifidobacterium longum is strain-dependent.

Antagonism of sphingosine 1-phosphate receptor-2 enhances migration of neural progenitor cells toward an area of brain

BACKGROUND AND PURPOSE

We have previously shown that the sphingosine 1-phosphate (S1P)/S1P receptor-1 (S1P(1)R) axis contributes to the migration of transplanted neural progenitor cells (NPCs) toward areas of spinal cord injury. In the current study, we examined a strategy to increase endogenous NPC migration toward the injured central nervous system to modify S1PR.

METHODS

S1P concentration in the ischemic brain was measured in a mouse thrombosis model of the middle cerebral artery. NPC migration in vitro was assessed by a Boyden chamber assay. Endogenous NPC migration toward the insult was evaluated after ventricular administration of the S1P(2)R antagonist JTE-013.

RESULTS

The concentration of S1P in the brain was increased after ischemia and was maximal 14 days after the insult. The increase in S1P in the infarcted brain was primarily caused by accumulation of microglia at the insult. Mouse NPCs mainly expressed S1P(1)R and S1P(2)R as S1PRs, and S1P significantly induced the migration of NPCs in vitro through activation of S1P(1)R. However, an S1P(1)R agonist failed to have any synergistic effect on S1P-mediated NPC migration, whereas pharmacologic or genetic inhibition of S1P(2)R by JTE-013 or short hairpin RNA expression enhanced S1P-mediated NPC migration but did not affect proliferation and differentiation. Interestingly, administration of JTE-013 into a brain ventricle significantly enhanced endogenous NPC migration toward the area of ischemia.

CONCLUSIONS

Our findings suggest that S1P is a chemoattractant for NPCs released from an infarcted area and regulation of S1P(2)R function further enhances the migration of NPCs toward a brain infarction.

Prolyl isomerase, Pin1: new findings of post-translational modifications and physiological substrates in cancer, asthma and Alzheimer's disease

The peptidyl prolyl cis/trans isomerase Pin1 specifically binds phosphorylated Ser/Thr-Pro protein motifs and catalyzes the cis/trans isomerization of the peptide bond. Accumulating studies have revealed that Pin1 isomerase activity is regulated by its post-translational modifications, including phosphorylation and oxidation. Various transcription factors and regulators have been identified as substrates for Pin1. It enhances AP-1 activity via isomerization of both c-Jun and c-Fos for cellular proliferation and stabilizes the oncosuppressors p53 and p73 against DNA damage at the checkpoint. We demonstrated the association between the intracellular form of Notch1 (NIC) and Pin1 by analyzing Pin1/p53 double-knockout mice. Pin1 also regulates the post-transcriptional level of some cytokines, associated with asthma, that possess 3' untranslated region AU-rich elements (AREs) via interaction withAUF1, the nucleoprotein in the ARE-binding complex. Pin1 has been identified as the molecular partner of tau and amyloid precursor protein (APP), the key factors of Alzheimer's disease (AD). It interacts with the phosphorylated Thr-231 of tau and regulates its activity to bind microtubules. It further interacts with the phosphorylated Thr-668 of APP and affects its metabolism. Thus, Pin1 is probably involved in the pathogenesis of human diseases, including cancer, asthma, and AD, presenting an attractive target for future therapeutical drugs.

Protection against aminoglycoside-induced ototoxicity by regulated AAV vector-mediated GDNF gene transfer into the cochlea

Since standard aminoglycoside treatment progressively causes hearing disturbance with hair cell degeneration, systemic use of the drugs is limited. Adeno-associated virus (AAV)-based vectors have been of great interest because they mediate stable transgene expression in a variety of postmitotic cells with minimal toxicity. In this study, we investigated the effects of regulated AAV1-mediated glial cell line-derived neurotrophic factor (GDNF) expression in the cochlea on aminoglycoside-induced damage. AAV1-based vectors encoding GDNF or vectors encoding GDNF with an rtTA2s-S2 Tet-on regulation system were directly microinjected into the rat cochleae through the round window at 5 x 10(10) genome copies/body. Seven days after the virus injection, a dose of 333 mg/kg of kanamycin was subcutaneously given twice daily for 12 consecutive days. GDNF expression in the cochlea was confirmed and successfully modulated by the Tet-on system. Monitoring of the auditory brain stem response revealed an improvement of cochlear function after GDNF transduction over the frequencies tested. Damaged spiral ganglion cells and hair cells were significantly reduced by GDNF expression. Our results suggest that AAV1-mediated expression of GDNF using a regulated expression system in the cochlea is a promising strategy to protect the cochlea from aminoglycoside-induced damage.

Antibacterial activity of bovine lactoferrin hydrolysate against mastitis pathogens and its effect on superoxide production of bovine neutrophils

Antibacterial activity of bovine lactoferrin hydrolysates (LFH) on microorganisms isolated from bovine mastitis, and superoxide (O(2)(-)) production of bovine neutrophils were evaluated. Antibacterial effects of LFH were measured in vitro against Staphylococcus aureus, coagulase-negative staphylococci, Streptococci, Enterococci, Escherichia coli, Klebsiella pneumoniae, yeast-like fungi and Prototheca zopfii isolated from clinical cases of bovine mastitis. To compare susceptibilities against LFH, minimal inhibitory concentration (MIC) values were determined by a micro-plate assay method. Most organisms were sensitive to LFH. Prototheca zopfii was highly sensitive to LFH; the growth of the microorganism was inhibited completely even at 1 mug/ml. Staphylococcus aureus and Escherichia coli were resistant to LFH. The production of O(2)(-) by bovine neutrophils was used to evaluate the effect of LFH administration on functional activity. Increase in O(2)(-) production by bovine neutrophils occurred upon addition of LFH to neutrophils. These results demonstrate that LFH possesses antibacterial activity against pathogens that cause mastitis and activates neutrophil superoxide production.

Ablation of a peptidyl prolyl isomerase Pin1 from p53-null mice accelerated thymic hyperplasia by increasing the level of the intracellular form of Notch1

Tumor suppressor p53 is essential for checkpoint control in response to a variety of genotoxic stresses. DNA damage leads to phosphorylation on the Ser/Thr-Pro motifs of p53, which facilitates interaction with Pin1, a pSer/pThr-Pro-specific peptidyl prolyl isomerase. Pin1 is required for the timely activation of p53, resulting in apoptosis or cell cycle arrest. To investigate the physiological relationship between Pin1 and p53, we created Pin1-/-p53-/- mice. These p53-deficient mice spontaneously developed lymphomas, mainly of thymic origin, as well as generalized lymphoma infiltration into other organs, including the liver, kidneys and lungs. Ablation of Pin1, in addition to p53, accelerated the thymic hyperplasia, but the thymocytes in these Pin1-/-p53-/- mice did not infiltrate other organs. The thymocytes in 12-week-old Pin1-/-p53-/- mice were CD4(-)CD8(-) (double negative) and had significantly higher levels of the intracellular form of Notch1 (NIC) than the thymocytes of p53-/- or wild-type mice. Presenilin-1, a cleavage enzyme for NIC generation from full-length Notch1 was increased in the thymocytes of Pin1-/-p53-/- mice. Pin1 depletion also inhibited the degradation of NIC by proteasomes. These results suggest that both Pin1 and p53 control the normal proliferation and differentiation of thymocytes by regulating the NIC level.

Specific and efficient transduction of cochlear inner hair cells with recombinant adeno-associated virus type 3 vector

Recombinant adeno-associated virus (AAV) vectors are of interest for cochlear gene therapy because of their ability to mediate the efficient transfer and long-term stable expression of therapeutic genes in a wide variety of postmitotic tissues with minimal vector-related cytotoxicity. In the present study, seven AAV serotypes (AAV1-5, 7, 8) were used to construct vectors. The expression of EGFP by the chicken beta-actin promoter associated with the cytomegalovirus immediate-early enhancer in cochlear cells showed that each of these serotypes successfully targets distinct cochlear cell types. In contrast to the other serotypes, the AAV3 vector specifically transduced cochlear inner hair cells with high efficiency in vivo, while the AAV1, 2, 5, 7, and 8 vectors also transduced these and other cell types, including spiral ganglion and spiral ligament cells. There was no loss of cochlear function with respect to evoked auditory brain-stem responses over the range of frequencies tested after the injection of AAV vectors. These findings are of value for further molecular studies of cochlear inner hair cells and for gene replacement strategies to correct recessive genetic hearing loss due to monogenic mutations in these cells.

Herpes simplex esophagitis in the immunocompetent host

We report here a case of herpes esophagitis with Mallory-Weiss syndrome in an immunocompetent host. A 26-year-old man was admitted to our hospital because of common cold symptoms and eruptions on the body. On day 2 after hospitalization, the patient showed high-grade fever, odynophagia and hematemesis. Upper gastrointestinal endoscopic examination showed multiple ulcerations throughout the mid- and distal esophagus. Bleeding from a Mallory-Weiss tear was also seen. Follow-up endoscopic examinations showed whitish exudates on day 5. Histological examination of biopsy specimens showed Cowdry type A intranuclear inclusion bodies in epithelial cells. Positive staining of a specific antibody against herpes simplex virus-1 (HSV-1) was seen in the nuclei of esophageal epithelial cells. Primary HSV-1 infection was suspected because ELISA titers of serum IgM antibody against HSV-1 were high and titers of serum IgG antibody against HSV-1 increased from an almost cut-off ratio. A diagnosis of herpes esophagitis in an immunocompetent host was made. Our case is the first report of herpes esophagitis with Mallory-Weiss syndrome in the immunocompetent host. It is important to remind herpes esophagitis in cases of severe odynophagia even in immunocompetent hosts.

Large-Scale Production of Recombinant Viruses by Use of a Large Culture Vessel with Active Gassing

Adenovirus and adeno-associated virus (AAV) vectors are increasingly used for gene transduction experiments. However, to produce a sufficient amount of these vectors for in vivo experiments requires large-capacity tissue culture facilities, which may not be practical in limited laboratory space. We describe here a large-scale method to produce adenovirus and AAV vectors with an active gassing system that uses large culture vessels to process labor- and cost-effective infection or transfection in a closed system. Development of this system was based on the infection or transfection of 293 cells on a large scale, using a large culture vessel with a surface area of 6320 cm2. A minipump was connected to the gas inlet of the large vessel, which was placed inside the incubator, so that the incubator atmosphere was circulated through the vessel. When active gassing was employed, the productivity of the adenovirus and AAV vectors significantly increased. This vector production system was achieved by improved CO2 and air exchange and maintenance of pH in the culture medium. Viral production with active gassing is particularly promising, as it can be used with existing incubators and the large culture vessel can readily be converted for use with the active gassing system.

Anti-apoptotic and neuroprotective effects of edaravone following transient focal ischemia in rats

To investigate the effect of an antioxidant edaravone on the apoptotic process, we examined Bax and Bcl-2 immunohistochemical expression and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) reactivity. Rat focal ischemia models were prepared by 2 h transient middle cerebral artery occlusion. Edaravone or physiological saline was intravenously administered after reperfusion. After 24 h of reperfusion, infarction volume assessments, Bax and Bcl-2 immunohistochemistry and TUNEL staining were performed as well as neurological evaluation. Cortical cerebral blood flow was not statistically different between the treatment-groups. Edaravone-treated animals showed significantly improved neurological outcome. Total and cortical infarct volumes in the edaravone group significantly decreased. In addition, edaravone-treatment provided a significant reduction in the number of TUNEL-positive apoptotic cells, a decrease in Bax immunoreactivity and an increase in Bcl-2 expression within the peri-infarct area. Edaravone shows an excellent neuroprotective effect against ischemia/reperfusion brain injury through a Bax/Bcl-2 dependent anti-apoptotic mechanism.

Differential effects of sublethal ischemia and chemical preconditioning with 3-nitropropionic acid on protein expression in gerbil hippocampus

Pretreatment with a low dose of 3-nitropropionic acid (3-NPA) has been shown to induce ischemic tolerance in the gerbil hippocampus. It is well known that sublethal (2-min) ischemia also induces ischemic tolerance. To investigate the acquisition of ischemic tolerance with 3-NPA, we examined the protein expression after 3-NPA treatment in comparison with sublethal ischemia. Immunohistochemical studies revealed intense expression of Bcl-2 and Bcl-xL in the hippocampal CA1 area after 3-NPA treatment. Furthermore, the time course of the expression of Bcl-xL showed a similar pattern to the acquisition of ischemic tolerance by 3-NPA treatment. The induction of Bcl-xL occurred in the hippocampal CA1 area at 24 h after 3-NPA treatment, and significant induction was observed at 48 h. Western blot analysis of hippocampus harvested 48 h after the pretreatment, showed that the expression of Bcl-2 and Bcl-xL was significantly increased by either 3-NPA treatment or 2-min ischemia. However, PMCA1 and HSP70 protein expression increased only in the sublethal ischemia treated group. The difference between 3-NPA treated group and control group was not statistically significant. These results suggest that Bcl-2 and Bcl-xL are essential for acquisition of ischemic tolerance, while HSP70 and PMCA1 play important roles in the enhancement of ischemic tolerance.

Screening of Dairy Yeast Strains for Probiotic Applications

To evaluate the potential of yeasts of dairy origin as probiotics, we tested 8 species including Candida humilis, Debaryomyces hansenii, Debaryomyces occidentalis, Kluyveromyces lactis, Kluyveromyces lodderae, Kluyveromyces marxianus, Saccharomyces cerevisiae, and Yarrowia lipolytica, isolated from commercial blue cheese and kefir. Strains were randomly selected from each species and tested for their ability to adhere to human enterocyte-like Caco-2 cells in culture. Among the 8 species, K. lactis showed higher adhesive ability than K. marxianus, K. lodderae, and D. hansenii. The other 4 species were poorly adhesive. All species other than K. marxianus and C. humilis were resistant to acidic conditions. In the presence of bile acid, growth inhibition was undetectable when incubation was carried out at 27 degrees C; however, it was evident for C. humilis and a strain of D. occidentalis when incubated at 37 degrees C. Moreover, the influence of proteinase treatment of living cells of K. lactis and K. lodderae on their adhesion to Caco-2 cells was evaluated. Although a slight reduction was recognized when K. lactis was treated with proteinase K, the influence of intestinal protease treatments of pepsin followed by trypsin was negligible. These results indicated that a proteinaceous factor was unlikely to be involved in adhesion of K. lactis and K. lodderae to Caco-2 cells. No stimulation of IL-8 synthesis by Caco-2 cells was recognized in the presence of K. lactis. In conclusion, K. lactis was the most attractive to continue study for use as probiotic microorganisms.

Upregulation of GluR2 decreases intracellular Ca2+ following ischemia in developing gerbils

Developing animals are known to be resistant to cerebral ischemia. To investigate the mechanisms by which developing animals exhibit ischemic resistance, we examined the changes in intracellular calcium ([Ca2+]i) after oxygen-glucose deprivation (OGD) using hippocampal slices from gerbils. We found that increases of [Ca2+]i in hippocampal CA1 neurons is significantly less after OGD in developing gerbils than in adults. Western blot analysis of AMPA (alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid) receptors (AMPARs) showed that GluR2 expression, but not that of the other AMPARs is significantly higher in developing gerbils than in adults. Expression of the anti-apoptotic proteins such as HSP70, Bcl-XL, and plasma membrane Ca2+-ATPase type1 (PMCA1) are not higher in the developing gerbils than in adults. These results suggest that the higher expression of GluR2 is important for the smaller increases in [Ca2+]i and enhanced resistance to ischemia-induced neuronal damage in developing animals.

Partial Characterization of Dextran-Degrading Enzyme Obtained from Blue Cheese

Degradation of dextran beads was observed when the water-soluble fraction of a blue cheese extract was applied to the top of a Sephadex G-150 or G-200 column. This phenomenon suggests the presence of a specific enzyme that can hydrolyze dextran. After removal of casein components from the blue cheese fraction, ammonium sulfate treatment and gel filtration chromatography were performed to isolate the enzyme fraction. The enzymatic products were analyzed by thin-layer chromatography and gel filtration chromatography and identified as isomaltooligosaccharides. The isoelectric point of this enzyme fraction was approximately 4.9, as determined by isoelectric focusing using Rotofor, and the molecular weight of the fraction was 65 kDa, as estimated by sodium dodecyl sulfate (SDS)-PAGE. Optimum pH for enzymatic activity was 5.0 to 5.3. A partial N-terminal amino acid sequence of 20 residues was determined to be ATPDEWRSRSIYFMLTDRGA from an enzyme fraction further purified by ion-exchange chromatography and native PAGE. This sequence showed a maximum homology of 80% with alpha-amylase or Taka amylase that originated from various microorganisms.

Ischemic preconditioning decreases intracellular zinc accumulation induced by oxygen-glucose deprivation in gerbil hippocampal CA1 neurons

In normal gerbils, intracellular zinc ions ([Zn2+]i) and calcium ions ([Ca2+]i) accumulate in hippocampal CA1 neurons after global ischemia. We examined whether ischemic preconditioning modifies these changes in gerbil hippocampal slices. In normal slices, large increases in [Zn2+]i and [Ca2+]i were observed in the stratum radiatum of the CA1 area after oxygen-glucose deprivation. In preconditioned slices, there were significantly decreased peak levels of [Zn2+]i and [Ca2+]i in CA1. However, there were no differences in the peak levels of these ions in CA3 and dentate gyrus. These results suggest that modified [Zn2+]i and [Ca2+]i accumulation after an ischemic insult might be important for the mechanisms of ischemic tolerance induced by preconditioning.

In situ generation of pseudotyped retroviral progeny by adenovirus-mediated transduction of tumor cells enhances the killing effect of HSV-tk suicide gene therapyin vitro andin vivo

BACKGROUND

Hybrid adeno-retroviral vector systems utilize the high efficiency of adenovirus transduction to direct the in situ production of retroviral progeny. In this study, we show that a single-step transduction of glioma cells with trans-complementing hybrid adeno-retroviral vectors effectively turns these cells into retrovirus vector-producing cells, which in turn facilitates the transduction of adjacent cells.

METHODS

We have adapted the adeno-retroviral hybrid viral vector system to enhance the ganciclovir (GCV) killing of glioma cells following transfer of the herpes simplex virus thymidine kinase (HSV-tk) gene. To assess the effect of the in situ production of retroviral vectors on the transduction efficiency of glioma cells, 9L cells were transduced with adeno-retroviral hybrid vectors that separately express a retroviral genome (AVC2.GCEGFP or AVC2.GCTK) and retroviral packaging proteins (AxTetGP and AxTetVSVG). The generation of an integrated HSV-tk provirus by trans-complementation of the adeno-retroviral vectors was verified by analysis of the flanking retroviral LTR sequences. Tumors established on nu/nu mice were injected with the viruses followed by intraperitoneal injections of either PBS or GCV. We also estimated the copy numbers of the HSV-tk transgene present in the tumors of the treated mice. To determine the expression pattern of the HSV-tk transcripts within a tumor, in situ hybridization analysis was performed using an RNA probe specific for HSV-tk.

RESULTS

The co-transduction of rat 9L glioma cells with AVC2.GCEGFP together with vectors expressing packaging proteins of retroviruses increased the transduction efficiency. Transduction with AVC2.GCTK together with packaging vectors increased the in vitro sensitivity of cells to the pro-drug GCV by one log compared with control cells that were incapable of generating retrovirus. In vivo, the injection of established subcutaneous 9L tumors on athymic mice with a combination of AVC2.GCTK and packaging vectors followed by GCV treatment resulted in complete tumor regression in 50% of tumors at day 22, while no tumor regression was observed in control animals. Retroviral sequences diagnostic of 3' LTR reduplication in vivo were detected in genomic DNA extracted from the transduced tumors, indicating pro-viral integration of the retroviral genome derived from the adeno-retroviral hybrid vector. Furthermore, the relative copy number of the HSV-tk gene in tumors treated with the adeno-retroviral vectors was up to approximately 250-fold higher than in control tumors. In situ hybridization suggested dispersion of the HSV-tk product across a wider area of the tumor than in control tumors, which indicates the spread of the in situ generated retroviruses.

CONCLUSIONS

Although the efficacy of this system has to be evaluated in orthotopic models, our observations suggest that this hybrid adeno-retroviral vector system could improve the suicide gene therapy of tumors.

Effect of infusing lactoferrin hydrolysate into bovine mammary glands with subclinical mastitis

The therapeutic effect of administering lactoferrin hydrolysate (LFH) into the mammary glands of cows with subclinical mastitis was evaluated. Seven millilitres of a preparation of LFH (7% protein) was infused into 35 quarters of 25 cows with subclinical mastitis. The numbers of bacteria in the milk from infected quarters decreased, and bacteria disappeared by the 14th day after the administration of LFH. The mean somatic cell counts (SCC) peaked one day after administration of LFH and the counts were significantly p < 0.01) decreased on days 7, 14 and 21 compared to those before the administration of LFH. The mean lactoferrin concentration in the milk peaked on days 2 or 3 and then gradually decreased to day 14, returning to the level before the administration of LFH. It appears that administration of LFH may have a therapeutic effect when infused into the quarters of cows with subclinical mastitis.

Imbalance between apoptosis and telomerase activity in myelodysplastic syndromes: possible role in ineffective hemopoiesis

The myelodysplastic syndromes (MDS) are a group of disorders characterized by peripheral pancytopenia despite normo- or hyper-cellular bone marrow. This is thought to be due to apoptosis of hematopoietic bone marrow cells, resulting in ineffective hematopoiesis. The heterogeneous nuclear ribonucleoprotein (hnRNP) B1 is involved in pre-mRNA processing and binds to telomeric cDNA repeats. The hnRNP B1 is a marker for early cancer. The aim of our study was to clarify the relationships between prognosis and apoptosis, telomerase activity (TA) and hnRNP expression in the bone marrow. The subjects were 51 patients with MDS, including patients with refractory anemia (RA) (n = 32), refractory anemia with ringed sideroblasts (RARS) (n = 1), refractory anemia with excess blasts (RAEB) (n = 7), refractory anemia with excess blasts in transformation (RAEB-t) (n = 8) and chronic myelomonocytic leukemia (CMMoL) (n = 3). We also studied 6 cases with acute myelogenous leukemia (AML) arising from MDS (AML-MDS) and 10 control subjects. Bone marrow biopsies were stained immunohistochemically for caspase-3 (marker of apoptotic activity) and human telomerase reverse transcriptase (hTERT), and hnRNP B1. Fatal pancytopenia was the cause of death in 19 of the 51 patients. The caspase-3 positive cell rate was higher in MDS (16.3%) than in controls (4.4%) and AML-MDS (0.5%). The percentage of hnRNP B1-positive cells was higher in MDS (15.3%) and AML-MDS (56.3%) than in controls (5.6%). In MDS, hnRNP B1 levels were higher in RAEB and RAEB-t subtypes than in RA and RARS. The percentage of hTERT-positive cells was higher in AML-MDS (50.0%) than in controls (20.2%) and MDS (23.6%). Our findings suggest that activation of apoptosis occurs in MDS in the absence of hTERT expression, implicating high apoptosis in the absence of high TA with ineffective hematopoiesis. Poor prognosis correlated with higher caspase-3 and lower hTERT rates. In MDS, hnRNP B1 activity may be associated with leukemic transformation.

Distinct patterns of gene transfer to gerbil hippocampus with recombinant adeno-associated virus type 2 and 5

Genetic modification of the gerbil hippocampal neuronal cells in vivo helps us understand the mechanisms of neuronal function under various circumstances such as ischemic insult. In this study, we examined the distinct distribution of the recombinant adeno-associated virus type 2 (rAAV2) and rAAV5 vectors for gene delivery to primary cultured cells and the gerbil hippocampus. Mixed cortical cultures containing both neurons and astrocytes from E17 rat embryos were infected with rAAVs containing the Cytomegalovirus virus (CMV) promoter. rAAV2 was preferably transduced to neurons, whereas rAAV5 was inclined to be transduced to astrocytes in vitro. rAAV2 and rAAV5 vectors, each with the CMV or Rous sarcoma virus (RSV) promoter, were injected into the gerbil hippocampus using a stereotaxic apparatus. Five days after injection, transgene expression was analyzed with X-gal staining. In the gerbil hippocampus, rAAV5 with the CMV promoter achieved a higher overall transgene expression than rAAV2 with the CMV promoter. The transgene expression of rAAV2 with the RSV promoter was found in the pyramidal and granular cells, while the transgene expression of rAAV5 with the RSV promoter was preferentially found in the granular cells. These findings would be valuable in optimizing rAAV-mediated gene transfer to the gerbil hippocampus.