OP0008 A NOVEL SITE-SPECIFIC PEGYLATED IL-2 WITH POTENT AND TREG-SELECTIVE ACTIVITY IN VIVO

Background

Decreased regulatory T cells (Tregs) and Treg dysfunction are hallmarks of a various autoimmune and inflammatory diseases. While low-dose IL-2 therapy induces Treg expansion in vivo and has clinical benefits in some diseases (e.g., SLE and chronic graft-versus-host disease [GvHD]), there are many concerns about adverse events due to low Treg-selectivity. Furthermore, frequent dosing is needed due to the short half-life.

Objectives

We discovered a novel site-specific PEGylated IL-2 variant, KKC80, with high Treg selectivity and a long half-life in vivo, which overcomes the issues of low-dose IL-2 therapy.

Methods

Based on the co-crystal structure of wild-type IL-2 and its heterotrimeric receptor (PBD ID: 2ERJ), amino acid residues that were to be PEGylation sites were substituted with oAzZLys, an azide-containing lysine derivative. The PEG molecule was site-specifically attached to oAzZLys-incorporated IL-2 by copper-free click chemistry. The binding property to the IL-2 receptors were measured by surface plasmon resonance (SPR). In vitro, Treg selectivity was evaluated by the IL-2-dependent proliferation activity of Tregs and NK cells from human peripheral blood mononuclear cells (PBMCs). In vivo pharmacological activity after the single subcutaneous administration in cynomolgus monkeys was measured by changes in Treg count and Treg activation status in peripheral blood by flow cytometry. Pharmacokinetic parameters were calculated according to serum PEGylated IL-2 concentration. Efficacy in mouse xenogeneic GvHD model using human PBMC-transplanted NOG mice and in monkey DTH model were evaluated.

Results

A novel PEGylated IL-2, KKC80 (human IL-2 desA1/C125S /I129oAzZLys_W-shaped 80 kDa PEG) was discovered by optimizing the PEGylation site and PEG structure based on Treg selectivity and PK. SPR analysis showed that the binding affinity of KKC80 to CD25 was moderately decreased from wild-type IL-2, while binding affinity of KKC80 to IL-2Rβγ was remarkably decreased due to a significant change of the association rate constant. In vitro, wild-type IL-2 activated both Tregs and NK cells in the same concentration range, whereas KKC80 selectively activated Tregs. The Treg selectivity of KKC80 was comparable to another IL-2 mutein, Fc.IL-2 V91K. KKC80, but not Fc.IL-2 V91K, retained its biological activity, even in the presence of a large amount of recombinant soluble CD25, which mimicked the endogenous decoy receptor for IL-2. In monkeys, KKC80 selectively increased peripheral blood Tregs in a dose-dependent manner; the average maximum rate of increase of Treg count in animals treated with 0.01, 0.03, 0.1, 0.3 and 1 mg/kg was 1.5, 3.5, 28, 50 and 154-fold, respectively. In contrast to Tregs, the rates of increase of conventional CD4+ T, CD8+ T and NK cells were low. The Treg increase peaked on day 8 or 11 and lasted for over day 29. KKC80 showed a more sustained upregulation of functional Treg markers (e.g., Foxp3 and CD25) in comparison to Fc.IL-2 V91K. The half-life of KKC80 was calculated as 83.5 to 150 h. At high doses, inflammation-related adverse effects, including increased CRP (≥0.3 mg/kg) and deterioration of general conditions (1 mg/kg) were observed. In the mouse xenogenic GvHD model, KKC80 ameliorated GvHD symptoms and suppressed multiple tissue inflammation markers. Decreased soluble CD25 and IFN-γ were also confirmed, suggesting Treg-mediated anti-inflammatory effect by KKC80 administration were exerted in vivo. In the monkey DTH model, KKC80 suppressed skin inflammation and antibody production.

Conclusion

Among next-generation IL-2 variants, KKC80 showed a best-in-class biological profile for Treg activation. A drastic and sustained increase of Tregs with high Treg-selectivity and anti-inflammatory effects were observed in vivo. These data suggest that in comparison to current IL-2 therapy, KKC80 provides superior therapeutic index and efficacy in patients with autoimmune and inflammatory diseases.

Figure 1.

Disclosure of Interests

Masahiro Ikeda Employee of: Kyowa Kirin Co., Ltd., Shinpei Yamaguchi Employee of: Kyowa Kirin Co., Ltd., Masumi Murakami Employee of: Kyowa Kirin Co., Ltd., Shigeki Takaoka Employee of: Kyowa Kirin Co., Ltd., Yasuko Sakaguchi Employee of: Kyowa Kirin Co., Ltd., Shunki Yasui Employee of: Kyowa Kirin Co., Ltd., Kousuke Iijima Employee of: Kyowa Kirin Co., Ltd., Kenichiro Nanya Employee of: Kyowa Kirin Co., Ltd., Hideyuki Onodera Employee of: Kyowa Kirin Co., Ltd., Toru Amano Employee of: Kyowa Kirin Co., Ltd.

Lath formation mechanisms and twinning as lath martensite substructures in an ultra low-carbon iron alloy

Lath martensite is the dominant microstructural feature in quenched low-carbon Fe-C alloys. Its formation mechanism is not clear, despite extensive research. The microstructure of an Fe-0.05 C (wt.%) alloy water-quenched at various austenitizing temperatures has been investigated using transmission electron microscopy and a novel lath formation mechanism has been proposed. Body-centered cubic {112}〈111〉-type twin can be retained inside laths in the samples quenched at temperatures from 1050 °C to 1200 °C. The formation mechanism of laths with a twin substructure has been explained based on the twin structure as an initial product of martensitic transformation. A detailed detwinning mechanism in the auto-tempering process has also been discussed, because auto-tempering is inevitable during the quenching of low-carbon Fe-C alloys. The driving force for the detwinning is the instability of ω-Fe(C) particles, which are located only at the twinning boundary region. The twin boundary can move through the ω ↔ bcc transition in which the ω phase region represents the twin boundary.

Diagnostic accuracy of plasma atrial natriuretic peptide concentrations in cats with and without cardiomyopathies

OBJECTIVES

Plasma atrial natriuretic peptide (ANP) levels have been reported to be elevated in cats with cardiomyopathy. We investigated the diagnostic accuracy of plasma ANP concentration as an indicator of the severity of cardiomyopathies.

ANIMALS

This study included 78 control cats and 83 cats with various types of cardiomyopathy.

METHODS

This was a prospective multicentre study. Control cats were determined to have a normal heart, and diseased cats were diagnosed by echocardiography. Diseased cats were divided into asymptomatic cats without left atrial dilation (LAD), asymptomatic cats with LAD, and cats with heart failure. Plasma C-terminal ANP concentrations were measured using chemiluminescence.

RESULTS

The median plasma ANP concentration in controls was 43.3 (interquartile range, 33.0-56.3) pg/mL. Plasma ANP values were significantly higher in the cardiomyopathic cats with LAD and heart failure, but the values in cats without LAD were comparable to those in control cats. To distinguish cats with cardiomyopathy from controls, a plasma ANP concentration >77.5 pg/mL afforded sensitivity of 66.3% and specificity of 84.6%. Use of plasma ANP concentration >110.9 pg/mL to identify cats with LAD had a sensitivity of 73.6% and specificity of 93.5%. The areas under the receiver-operating characteristic curve were 0.80 and 0.86.

CONCLUSIONS

Plasma ANP concentrations were higher in cats with more advanced cardiomyopathy. Although assaying the ANP concentration alone may not help to diagnose cardiac disease, measuring provides additional information that is useful for assessing the severity of cardiomyopathies.

Storage stability of serum formulations containing ofloxacin for autologous serum eardrop therapy

OBJECTIVE

The storage stability of serum formulations containing ofloxacin for autologous serum eardrop therapy was evaluated for microbiological quality and component stability.

METHODS

Sterile serum formulations were prepared by mixing human serum and ofloxacin otic solution (1:1, v/v). To simulate eardrop contamination with external ear surface substances, prepared serum formulations were contaminated with a cotton swab that was rubbed sufficiently on the human external ear. Formulations were stored at 4 °C or room temperature in the dark. Colony forming units (CFUs), ofloxacin, and basic fibroblast growth factor (bFGF) concentrations in the stored serum formulations were determined.

RESULTS

The growth of microorganisms derived from the external ear was not detected in serum formulations after storage for 14 days, regardless of temperature. However, microbial growth was detected in serum formulations stored without ofloxacin, indicating that this is necessary for storage. In addition, concentrations of ofloxacin and bFGF did not decrease over 14 days, indicating that ofloxacin and bFGF in serum formulations are stable for this time period.

CONCLUSION

The present study indicates that the efficacy and safety of serum formulations used as a therapy for perforated eardrums are stable and safe for at least 14 days.

Comparative Studies on Lipid Peroxidation in the Kidney of Rats, Mice, and Hamsters and on the Effect of Cysteine, Glutathione, and Diethyl Maleate Treatment on Mortality and Nephrotoxicity After Administration of Potassium Bromate

As an index of lipid peroxidation (LPO), levels of thiobarbituric acid (TBA)-reactive substances were examined in the kidneys of male F344 rats, BDF1, CDF1, and B6C3F1 mice, and Syrian golden hamsters after a single intravenous (IV) administration of potassium bromate (KBrO3) at various doses. In the rats, LPO levels were significantly increased in both a dose-dependent and time-dependent manner. However, when the rats were given intraperitoneal (IP) injection of cysteine, the levels of LPO were not significantly different between KBrO3-treated animals and controls. In CDF1 mice, the slight increases in LPO levels observed were much weaker and not statistically significant. On the other hand, treatment of BDF1 and B6C3F1 mice or hamsters with KBrO3 resulted in decreased values as compared to controls. The effect of treatment with cysteine, glutathione (GSH), or diethyl maleate (DEM) on mortality was tested in male F344 rats given IV injection of KBrO3 at various doses. Significant reduction and elevation in the mortality were observed in rats treated with cysteine or GSH and DEM, respectively. Significant dose-dependent and time-dependent increases were observed in the levels of serum non-protein nitrogen (NPN), blood urea nitrogen (BUN), and creatinine, and absolute and relative weight of the kidneys in male F344 rats administered KBrO3 IV. Microscopically, the appearance of numerous eosinophilic droplets in the cytoplasm of proximal tubular epithelium of KBrO3-treated rats was noteworthy. All these changes were reduced and exacerbated by treatment with cysteine or GSH and DEM, respectively. The possibility of LPO formation in the kidney by active oxygen radicals generated by KBrO3 is suggested. A possible relationship between LPO levels in the kidney and species differences in the renal toxicity and carcinogenicity of KBrO3 is implicated.

Measurement and comparison of individual external doses of high-school students living in Japan, France, Poland and Belarus-the 'D-shuttle' project

Twelve high schools in Japan (of which six are in Fukushima Prefecture), four in France, eight in Poland and two in Belarus cooperated in the measurement and comparison of individual external doses in 2014. In total 216 high-school students and teachers participated in the study. Each participant wore an electronic personal dosimeter 'D-shuttle' for two weeks, and kept a journal of his/her whereabouts and activities. The distributions of annual external doses estimated for each region overlap with each other, demonstrating that the personal external individual doses in locations where residence is currently allowed in Fukushima Prefecture and in Belarus are well within the range of estimated annual doses due to the terrestrial background radiation level of other regions/countries.

Flux growth of patterned LiCoO2 crystal arrays directly on a Pt substrate in molten LiNO3

We demonstrate a new way to prepare hollow-structured LiCoO₂ crystals directly on a Pt substrate for the first time through a combination of semi-additive electrodeposition of a Co core and subsequent flux growth in molten LiNO₃.

Novel surgical repair with bilateral gluteus muscle patching for intractable rectovaginal fistula

We created a novel surgical repair for intractable rectovaginal fistula and treated four patients who had previously undergone unsuccessful surgery. An X-shaped skin incision was made on the perineum, and then the rectum was carefully divided from the vagina. Defects of both the rectum and the vagina were closed with vertical mattress sutures. The external sphincter muscle also was approximated. The gluteus muscle was identified through another skin incision to the buttock, and cut at the attachment to the femur. Bilateral gluteus muscles were approximated at the midline of the perineum so that the vagina was sufficiently separated from the rectum. Established anorectal angle was 92.5 degrees (SD=6.4 degrees ). Mean resting pressure was 101.3 cm H2O (SD=13.1). All patients retained complete anal function without soiling. The unusual problem of erosion of the posterior vaginal wall with fistulation in a sexually active woman justifies greater efforts, and this surgical technique offers good prospects in this small group of patients.

Charge-density-wave destruction and ferromagnetic order in SmNiC2

X-ray scattering and electrical resistivity measurements were performed on SmNiC2. Satellite peaks characterized by an incommensurate wave vector (0.5, eta, 0) appear below 148 K, at which the resistivity shows an anomaly. The temperature dependence of thermal diffuse scattering above 148 K suggests critical phonon softening. These results indicate the formation of a charge-density-wave. The satellite peaks abruptly disappear and the resistivity sharply decreases when a ferromagnetic transition takes place at 17.7 K.

Tracheostomy can fatally exacerbate sleep-disordered breathing in multiple system atrophy

Tracheostomy has been employed to release the airway obstruction at the glottic level and to prevent sudden death in patients with multiple system atrophy (MSA). However, sudden death is possible even after tracheostomy. Nocturnal polysomnography showed that the apnea-hypopnea index became higher after tracheostomy, and all tracheostomized patients had frequent central sleep apneas.

A 13-week subchronic toxicity study of dietary administered morin in F344 rats

A subchronic toxicity study of a flavonoid morin was performed in both sexes of F344 rats with dietary administration at concentrations of 0%, 0.625%, 1.25%, 2.5% and 5% (w/w) for 13 weeks. No mortality or abnormal clinical signs were observed throughout the experimental period in any group. Although a slight tendency for increase in food intake was noted in both sexes of the 2.5% and 5.0% groups, slight non-significant body weight decrease was observed in 5.0% males. Significant increases in alanine transaminase (ALT; over 2.5%), alkali phosphatase (ALP; 1.25% and 5.0%) and relative liver weights (1.25% and 2.5%) in males and in gamma-glutamyl transpeptidase (gamma-GT), aspartate transaminase (AST), ALT, relative liver weights in the 2.5% and 5.0% females and ALP in 5.0% females were noted. Increased urea nitrogen and relative kidney weights at dose of 1.25% and above and creatinine at 5.0% were observed also in females. On histopathological observation, hepatocyte hypertrophy was detected in 3 of 10 5.0% females. Based on the above findings, the no-observed-adverse-effect level (NOAEL) for both sexes was estimated to be 0.625% (299 and 356 mg/kg b.w./day for males and females, respectively).

Chronic toxicity and carcinogenicity of dietary administered ammonium sulfate in F344 rats

Chronic toxicity and carcinogenicity studies of ammonium sulfate, used as a food additive in fermentation, were performed in male and female Fisher 344 rats at dietary concentrations of 0%, 0.1%, 0.6% and 3.0% in a 52-week toxicity study and 0%, 1.5% and 3.0% in a 104-week carcinogenicity study. Treatment with ammonium sulfate caused significant increase in kidney and/or liver weights in males and females of the 3.0% diet group, but no effects were found on survival rate, body weights, and hematological, serum biochemical or histopathological parameters at any dose levels in the chronic toxicity study. Regarding carcinogenicity, ammonium sulfate did not exert any significant influence on the incidences of tumors in any of the organs and tissues examined. It was concluded that the no observed adverse effect level of ammonium sulfate was the 0.6% diet, which is equivalent to 256 and 284 mg/kg b.w./day in males and females, respectively, and the compound is non-carcinogenic under the conditions of the study.

Sequential analysis of testicular lesions and serum hormone levels in rats treated with a Psoralea corylifolia extract

In order to clarify pathogenetic targets for the testicular toxicity of a extract of Psoralea corylifolia (P. corylifolia), F344 rats were fed diet containing 3% P. corylifolia extract for up to 12 weeks and subjected to hormone assays and histopathological examination on the testis and epididymis at weeks 1, 2, 4, 8 and 12 (Exp 1). Similar analyses were performed on 1, 3, 7 and 14 days after a single gavage administration of the P. corylifolia extract at a dose of 10 g/kg b.w. (Exp 2). In Exp 1, increase in the numbers of degenerated and exfoliated germ cells and loss of elongated spermatids beyond steps 7 or 8 were initially observed in the seminiferous tubules at week 1, followed by more pronounced degeneration of germ cells with depletion of post-meiotic populations from week 2. The tubular degeneration was associated with Leydig cell atrophy and persistent reduction of serum testosterone and FSH levels throughout the treatment period and a slight reduction of serum LH in later stages. In Exp 2, reduction of serum testosterone and FSH levels preceded degeneration of germ cells in stage VII and VIII tubules at 3 and 7 days after the administration. The results suggest that rapid androgen deprivation reflecting direct interference with Leydig cell function and simultaneous disturbance of the pituitary-testicular axis play pivotal roles in P. corylifolia extract-induced germ cell injury in seminiferous tubules.

Abnormal kainic acid receptor density and reduced seizure susceptibility in dystrophin-deficient mdx mice

Duchenne muscular dystrophy is characterized by a defect in dystrophin, which often causes mental retardation in addition to progressive muscular weakness. As dystrophin is localized in synaptic regions of the CNS, cognitive abnormalities associated with Duchenne muscular dystrophy are attributable to synaptic dysfunction. We report that dystrophin-deficient mdx mice were more resistant to kainic acid-induced seizures but not to GABA antagonist-induced seizures compared with the control mice. The kainic-acid receptor density in the brain was significantly lower in the mdx than in the control, although the density of muscarinic cholinergic receptors, another important neurotransmitter receptor for cognitive function, was normal. Moreover, mdx had significantly lower Timm staining intensity in the mossy fibers, which originate from the dentate granule cells and terminate on the pyramidal cells in the CA3 of the hippocampus. These results suggest that an instability of neurotransmitter receptors, such as kainate-type glutamate receptors, on synaptic membranes due to the disruption of dystrophin complex induces inefficient neurotransmission in Duchenne muscular dystrophy patients.

Resonant two-magnon Raman scattering and photoexcited States in two-dimensional mott insulators

We investigate the resonant two-magnon Raman scattering in two-dimensional (2D) Mott insulators by using a half-filled 2D Hubbard model in the strong coupling limit. By performing numerical diagonalization calculations for small clusters, we find that the Raman intensity is enhanced when the incoming photon energy is not near the optical absorption edge but well above it, being consistent with experimental data. The absence of resonance near the gap edge is associated with the presence of background spins, while photoexcited states for resonance are found to be characterized by the charge degree of freedom. The resonance mechanism is different from those proposed previously.

[A 90-day repeated dose oral toxicity study of magnesium chloride in F344 rats]

In order to examine the toxicity of magnesium chloride hexahydrate, four groups of 10 male and 10 female F344 rats received the compound by dietary supplementation at 2.5, 0.5, 0.1 or 0% for 90 days. No treatment-related death was observed during the study. Transient soft stool and sustained increase in water consumption were observed both in males and females of the 2.5% group and slight reduction in body weight gain was noted in the high-dose males. There were no toxic changes in food consumption, organ weights, hematology and biochemistry, and histopathological examinations in any treated-groups. Based on these results, the no-observed-adverse-effect-level was estimated to be 0.5%, and 2.5% is considered to be appropriate as highest dose for a 2-year carcinogenicity study.

Lattice-dictated conformers in bis(pyrazolyl)pyridine-based iron(II) complexes: Mössbauer, NMR, and magnetic studies

Iron(II) complexes [FeL(2)](ClO(4))(2).CH(3)CN, [FeL(2)](BPh(4))(2).2CH(3)CN, and [FeL(2)](PF(6))(2) with an FeN(6) chromophore of the same ligand L (2,6-bis(3,5-dimethylpyrazol-1-ylmethyl)pyridine) and differing counterions have been made and their crystal and molecular structures determined. The first two crystallized in triclinic space group P(-)1, and the third, with PF(6)(-) anion in Ibca space group. The FeL(2) complex ions in all lattices have similarly distorted octahedral geometry. Variable-temperature Mössbauer spectra of [FeL(2)](ClO(4))(2).CH(3)CN and [FeL(2)](PF(6))(2) measured in the temperature range 1.7-300 K reveal temperature-dependent populations of two different spin states with increased amount of low-spin form at high temperatures, a phenomenon unlike the normal spin crossover behavior; this abnormal behavior is interpreted here as due to the presence of two different conformations. It is very interesting to note that the two different compounds have similar spectra, Mössbauer parameters, and temperature dependence. But the variable-temperature Mössbauer spectra of [FeL(2)](BPh(4))(2).2CH(3)CN in the range 20-300 K do not show the presence of such different species but exhibit a clear phase transition at approximately 200 K. This phase transition is further supported by SQUID measurements. The results of variable-temperature (1)H NMR in CD(3)CN and the solution susceptibility measurement of all complexes also support the presence of high-spin and low-spin forms in solution. Hence, the complex ion [FeL(2)](2+) exhibits a thermally driven interconversion between low-spin and a high-spin structural forms-a phenomenon observed in the solid and solution states due to ligand dynamics. This is not due to the well-known spin crossover phenomenon. These results are compared with the case of normal spin crossover seen in [FeL'(2)](ClO(4))(2) (L' = 2,6-(bis(pyrazol-1-ylmethyl)pyridine)).

Significant accumulation of C(4)-specific pyruvate, orthophosphate dikinase in a C(3) plant, rice

The C(4)-Pdk gene encoding the C(4) enzyme pyruvate, orthophosphate dikinase (PPDK) of maize (Zea mays cv Golden Cross Bantam) was introduced into the C(3) plant, rice (Oryza sativa cv Kitaake). When the intact maize C(4)-Pdk gene, containing its own promoter and terminator sequences and exon/intron structure, was introduced, the PPDK activity in the leaves of some transgenic lines was greatly increased, in one line reaching 40-fold over that of wild-type plants. In a homozygous line, the PPDK protein accounted for 35% of total leaf-soluble protein or 16% of total leaf nitrogen. In contrast, introduction of a chimeric gene containing the full-length cDNA of the maize PPDK fused to the maize C(4)-Pdk promoter or the rice Cab promoter only increased PPDK activity and protein level slightly. These observations suggest that the intron(s) or the terminator sequence of the maize gene, or a combination of both, is necessary for high-level expression. In maize and transgenic rice plants carrying the intact maize gene, the level of transcript in the leaves per copy of the maize C(4)-Pdk gene was comparable, and the maize gene was expressed in a similar organ-specific manner. These results suggest that the maize C(4)-Pdk gene behaves in a quantitatively and qualitatively similar way in maize and transgenic rice plants. The activity of the maize PPDK protein expressed in rice leaves was light/dark regulated as it is in maize. This is the first reported evidence for the presence of an endogenous PPDK regulatory protein in a C(3) plant.

sFlt-1 gene-transfected fibroblasts: a wound-specific gene therapy inhibits local cancer recurrence

Local recurrence occurs frequently at the site of injury after surgical resection. On the other hand, fibroblasts have been shown to accumulate in the injured area to heal and remodel the damaged tissues. Therefore, fibroblasts are likely to be useful as wound-specific vectors for delivery of genes to sites of surgically injury. The present study was performed to investigate wound-specific migration of exogenously administered fibroblasts and efficacy of gene therapy using genetically engineered fibroblasts in an i.p. wound recurrence model in rats. We demonstrated that fibroblasts transfected with the GFP gene accumulated specifically around the site of injury immediately after i.p. injection. Then, fibroblasts transfected with an adenovirus designated as AdFex that encoded the soluble form of Flt-1 (sFlt-1), a vascular endothelial growth factor receptor, were administered i.p. to the rats to examine inhibition of tumor growth. At day 16 after implantation, a significantly smaller tumor volume and less microvessel density in wound sites were observed in the AdFex/fibroblast-treated rats than in controls. Furthermore, this treatment also resulted in an improved survival rate. In conclusion, autologous fibroblasts show promise as a wound-specific vector for gene therapy, and administration of sFlt-1 gene-engineered fibroblasts contributed to local control of the tumor around the injured tissue.

A prostaglandin E2 receptor subtype EP1 receptor antagonist (ONO-8711) reduces hyperalgesia, allodynia, and c-fos gene expression in rats with chronic nerve constriction

Chronic constriction injury (CCI) of the sciatic nerve in rats induces persistent mechanical hyperalgesia and allodynia. CCI is widely known as a model of neuropathic pain, and many studies using this model have been reported. Recently, c-fos has been used as a neural marker of pain, and various studies have assessed the relationship between hyperalgesia and c-fos expression in the lumbar spinal cord. In this study, we examined the role of a prostaglandin E2 receptor subtype EP1 receptor antagonist (ONO-8711) in a rat CCI model. EP1 receptor antagonist (EP1-ra) oral administration from day 8 to day 14 significantly reduced hyperalgesia and allodynia in the three pain tests on day 15. EP1-ra treatment from day 8 to 14 also reduced c-fos-positive cells in laminae I-II, III-IV, and V-X compared with saline treatment. A single dose of EP1-ra treatment on day 8 significantly reduced hyperalgesia and allodynia at 1 h and 2 h after administration, but the efficacy was not observed at 24 h. We conclude that EP1-ra treatment may be useful for hyperalgesia and allodynia and that EP1 receptor mechanisms are involved in the maintenance of c-fos gene expression induced by nerve injury.

IMPLICATIONS

We examined whether a prostaglandin E2 receptor subtype EP1 receptor antagonist abrogates neuropathic pain induced by chronic constriction injury model in rats. The EP1 receptor antagonist significantly reduced hyperalgesia, allodynia, and c-fos positive cells. These findings suggested that EP1 receptor antagonists may have a role in treatment of neuropathic pain.

Lack of modifying effects of eugenol on development of lung proliferative lesions induced by urethane in transgenic mice carrying the human prototype c-Ha-ras gene

To investigate the modifying effects of eugenol (EUG), a component of cigarette smoke, on lung carcinogenesis, male and female transgenic mice carrying the human prototype c-Ha-ras gene (rasH2 mice) were given a single intraperitoneal injection of 250 mg/kg urethane (UR) or saline, followed by a diet containing 6,000 ppm EUG or basal diet for 26 weeks. Their non-transgenic CB6F1 littermates (non-Tg mice) were also treated in the same manner. In both male and female rasH2 mice, alveolar/bronchiolar hyperplasias, adenomas and carcinomas were observed in all UR-treated groups. However, there were no significant intergroup differences in the incidences and multiplicities of these lesions between the UR alone and UR + EUG groups. In non-Tg mice, alveolar/bronchiolar hyperplasias, adenomas or carcinomas were sporadically observed in UR-treated groups of both sexes, with no significant differences in the incidences and multiplicities between the UR alone and UR + EUG groups. There were no intergroup differences between them in the PCNA-positive ratios of adenomas or carcinomas and the areas of adenomas or carcinomas to the whole lung area examined. The present results suggest that the EUG treatment does not exert modifying effects on lung carcinogenesis induced by UR in both male and female rasH2 mice and non-Tg mice.

[Follow-up study of myasthenia gravis: evaluation of thymectomy in 300 patients]

From June 1975 to March 1999, 300 patients of myasthenia gravis(MG) have undergone thymectomy. Among these patients, 69 cases were classified as ocular type of MG(including 15 cases with thymoma), and 231 were generalized type of MG(including 86 cases with thymoma). The efficacy of the treatment was investigated by evaluating current patients' life activity, which is classified in 6 groups(Remission, Much Improved, Improved, Unchanged, Worse, and Died). Among the 214 cases without thymoma, Remission was 75, Much Improved was 56, and Improved was 55, namely 86.9% of these cases showed Improved or better. Among 86 cases with thymoma, Remission was 14, Much Improved was 21, and Improved was 32, namely 77.9% of these cases showed Improved or better. We concluded that post-operative outcome of these patients regardless of thymoma were generally satisfactory, but it was necessary to carry out long term careful follow-up.

Human macrophage metalloelastase gene expression in colorectal carcinoma and its clinicopathologic significance

BACKGROUND

Human macrophage metalloelastase (HME), also referred as matrix metalloproteinase 12, has been shown to convert plasminogen into angiostatin, an essential inhibitor of tumor angiogenesis. The current study was designed to investigate the association of HME mRNA expression with disease progression of in patients with colorectal carcinoma.

METHODS

The expression of HME mRNA was quantified by Northern blot analysis in tumorous (T) and nontumorous (N) tissues obtained from 54 patients with primary colorectal carcinoma, and the ratio of these two tissue types was defined as the HME T/N ratio. The prognostic significance of this ratio after surgery, along with its correlation with disease progression and metastatic potential, was evaluated. The tissues also were subjected to in situ hybridization analysis for HME. The microvessel count after immunohistochemical staining of factor VIII was used to assess angiogenesis.

RESULTS

The HME T/N ratio showed an inverse correlation with the depth of the intestinal wall invasion, the lymphatic invasion, and the vascular invasion. The patients with overexpression of HME mRNA (HME T/N ratio > 1.191) significantly demonstrated better survival compared with those patients who did not show overexpression of HME mRNA. In situ hybridization identified the colorectal carcinoma cells as mainly responsible for the signal shown in Northern blot analysis. A considerable but not statistically significant lower microvessel density (MVD) was observed in the patients with HME overexpression.

CONCLUSIONS

These findings demonstrate that the HME gene plays an important role in the inhibition of tumor progression in patients with colorectal carcinoma and that its overexpression is correlated closely with a better prognosis.

Human macrophage metalloelastase gene expression in colorectal carcinoma and its clinicopathologic significance

BACKGROUND

Human macrophage metalloelastase (HME), also referred as matrix metalloproteinase 12, has been shown to convert plasminogen into angiostatin, an essential inhibitor of tumor angiogenesis. The current study was designed to investigate the association of HME mRNA expression with disease progression of in patients with colorectal carcinoma.

METHODS

The expression of HME mRNA was quantified by Northern blot analysis in tumorous (T) and nontumorous (N) tissues obtained from 54 patients with primary colorectal carcinoma, and the ratio of these two tissue types was defined as the HME T/N ratio. The prognostic significance of this ratio after surgery, along with its correlation with disease progression and metastatic potential, was evaluated. The tissues also were subjected to in situ hybridization analysis for HME. The microvessel count after immunohistochemical staining of factor VIII was used to assess angiogenesis.

RESULTS

The HME T/N ratio showed an inverse correlation with the depth of the intestinal wall invasion, the lymphatic invasion, and the vascular invasion. The patients with overexpression of HME mRNA (HME T/N ratio > 1.191) significantly demonstrated better survival compared with those patients who did not show overexpression of HME mRNA. In situ hybridization identified the colorectal carcinoma cells as mainly responsible for the signal shown in Northern blot analysis. A considerable but not statistically significant lower microvessel density (MVD) was observed in the patients with HME overexpression.

CONCLUSIONS

These findings demonstrate that the HME gene plays an important role in the inhibition of tumor progression in patients with colorectal carcinoma and that its overexpression is correlated closely with a better prognosis.

Dose-threshold for thyroid tumor-promoting effects of orally administered kojic acid in rats after initiation with N-bis(2-hydroxypropyl) nitrosamine

In order to evaluate the threshold dose of thyroid tumor-promoting effects of KA, male F344 rats were initiated with N-bis(2-hydroxypropyl) nitrosamine (DHPN; 2000 mg/kg body wt., single s.c. injection) and, starting 1 week later, received pulverized basal diet containing 0%, 0.002%, 0.008%, 0.03%, 0.125%, 0.5% or 2%KA for 20 weeks. Five rats each in the 0%, 0.125%, 0.5% and 2%KA groups were sacrificed at week 12, and 10 rats each in all groups at week 20. As an additional experiment, three groups without DHPN initiation received basal diet, a diet containing 0.5% or 2%KA for 20 weeks. The serum T4 levels were significantly decreased in the DHPN-initiated groups given 0.125%KA or more at week 12. No significant decreases in serum T3 levels were observed in the groups treated with DHPN + KA and a significant increase was evident in the 2%KA-alone group at week 20. Some rats in the DHPN + 2%KA group at weeks 12 and 20 and the 2%KA-alone group at week 20 showed pronounced elevation of serum TSH. Thyroid weights were significantly increased in the DHPN-initiated groups receiving 0.5% and 2%KA at weeks 12 and 20 and in the 2%KA-alone group at week 20. Histopathologically, the incidences of focal thyroid follicular cell hyperplasias in the DHPN-initiated groups treated with 0.125%, 0.5% and 2%KA at week 20 were 5/10, 10/10 and 8/8 rats, respectively. At week 20, adenomas were observed in 7/10 rats in the DHPN + 0.5%KA group and 8/8 rats in the DHPN + 2%KA group, and carcinomas were observed in 6/8 rats in the DHPN + 2%KA group. In the groups without DHPN initiation, only focal follicular cell hyperplasia was observed in 1/9 rats in the 2%KA-alone group. These results suggest that the no-observed-adverse effect for the thyroid tumor-promoting effect of KA is 0.03% (15.5 mg/kg/day) under the present experimental conditions, and that KA possesses weak tumorigenic activity in rats due to continuous serum TSH stimulation by a non-genotoxic mechanism.

Immunohistochemical and ultrastructural studies of 2,6-dimethylaniline-induced nasal proliferative lesions in a rat two-stage nasal carcinogenesis model initiated with N-bis(2-hydroxypropyl)nitrosamine

Proliferative lesions induced by 2,6-dimethylaniline (DMA) in a two-stage rat nasal carcinogenesis model were immunohistochemically and ultrastructurally investigated. Male F344 rats received diet containing 3,000 ppm DMA for 52 weeks after initiation with a single subcutaneous injection of 2400 mg/kg of N-bis(2-hydroxypropyl)nitrosamine (DHPN). Histopathologically, proliferation of Bowman's glands, glandular hyperplasias, dysplastic foci, adenomas, and carcinomas were observed in treated rats. These nasal lesions mostly arose in the olfactory mucosa of the nasal cavity. Immunohistochemically, they were positive for cytokeratin and/or collagen type IV antibodies. Ultrastructurally, intracytoplasmic dense secretory granules (200-850 nm in diameter), identical to those in normal Bowman's glands, were observed in all the lesions, providing further support from an origin from these glands. Based on their cellular characterization, growth pattern and/or proliferative activity, two morphological continua were evident, one from dysplastic foci to carcinomas and the other from proliferation of Bowman's glands to glandular hyperplasias and adenomas. These results suggest that dysplastic foci arise from Bowman's glands and progress to carcinomas, while proliferation of Bowman's glands result in glandular hyperplasias and adenomas.

Decreased expression of c-myc family genes in thymuses from myasthenia gravis patients

The thymus is a critical organ for the elimination of autoreactive T cells by apoptosis. We studied the expression of apoptosis-associated genes, bcl-xL, bad, caspase-3, and c-myc family genes in myasthenia gravis (MG) thymuses. We observed that the mRNA levels of myc family genes, c-myc and max, were markedly reduced in MG thymuses. These results indicate that c-myc-mediated signaling is abnormal in MG thymuses. The levels of molecules whose expressions are associated with myc, such as STAM, prothymosin-alpha, and NFkappaB, were also analyzed.

Promoting effects of xylazine on development of thyroid tumors in rats initiated with N-bis(2-hydroxypropyl)nitrosamine and the mechanism of action

To cast light on whether xylazine hydrochloride (XZ), a veterinary medicine commonly used as a sedative agent for food-producing animals, has any promoting potential for thyroid carcinogenesis, the following studies were performed. In Experiment I, male F344 rats received a diet containing 1000 or 0 p.p.m. XZ for 52 weeks with or without initiation with 2400 mg/kg N:-bis(2-hydroxypropyl)nitrosamine (DHPN). Focal follicular cell hyperplasias, adenomas and/or carcinomas were induced in the DHPN alone, XZ alone and DHPN+XZ groups, and the incidences and multiplicities of these lesions in the DHPN+XZ group were significantly increased as compared with the DHPN alone case. In Experiment II, male F344 rats received a diet containing 1000 or 0 p.p.m. XZ and were examined for serum levels of triiodothyronine (T(3)), thyroxine (T(4)) and thyroid-stimulating hormone (TSH) at weeks 1, 2 and 4. In the XZ group, significant increase in thyroid weight and decrease in serum T(4) levels were observed at all time points. Serum T(3) and TSH levels were significantly decreased and increased, respectively, at week 1, but returned to within the control range thereafter. In Experiment III, male F344 rats received a diet containing 1000 or 0 p.p.m. XZ, they were examined for thyroid iodine uptake and organification of XZ after 1 and 2 weeks. The thyroidal iodine uptake per milligram of thyroid and the amount of iodine bound to 1 mg protein showed a tendency for decrease at week 1 and significant decrease at week 2. These results indicate that XZ has tumor-promoting effects on thyroid follicular cells, and suggest an involvement of alterations in thyroid-related hormone levels due to inhibition of thyroid iodine uptake and organification, resulting, provably, in serum TSH stimulation depending on continuous reduction of serum T(4) level through the feedback system in the pituitary-thyroid axis.

[A case of potassium-sensitive periodic paralysis with cardiac dysrhythmia controlled with imipramine and acetazolamide]

We report a patient with potassium-sensitive periodic paralysis with cardiac dysrhythmia. The patient was a 16-year-old man. He presented with asymptomatic ventricular dysrhythmia and periodic paralysis when he was 6 and 12 years old, respectively. Physical examination revealed slight dysmorphic features such as hypoplastic mandible, low-set ears and clinodactyly. Through an exercise test, a potassium tolerance test and a muscle biopsy, his illness was diagnosed as potassium-sensitive periodic paralysis with cardiac dysrhythmia. For the treatment of his episodic paralysis, we started acetazolamide, which improved both the incidence and the severity of paralysis. However, the incidence of cardiac dysrhythmia was increased after the use of acetazolamide. Routine anti-arrhythmic drugs such as lidocaine failed to control his ventricular dysrhythmia. Only imipramine showed its efficacy by improving the degree and the incidence of cardiac dysrhythmia without aggravating periodic paralysis. This syndrome is relatively rare and there have been no standard protocols for the treatment. We propose the combination of acetazolamide and imipramine as the first choice for this clinical entity. We also discussed the efficacy of the exercise test. It enabled us to confirm the diagnosis of periodic paralysis safely and easily by recording the change of compound muscle action potential amplitudes.

Chemokine receptor expression on T cells in blood and cerebrospinal fluid at relapse and remission of multiple sclerosis: imbalance of Th1/Th2-associated chemokine signaling

The expression of chemokine receptors on lymphocytes in the blood and CSF of multiple sclerosis (MS) patients was analyzed at relapse and remission. Both CD4+ and CD8+ cells in CSF at relapse were enriched for Th1-type receptors CXCR3 and CCR5 expression, and were reduced for Th2-type receptors CCR3 and CCR4 expression compared with those of the blood. CCR1 and CCR2 expressions on T cells were increased in CSF and blood, respectively. At remission, CCR5 expression, but not CXCR3 expression, was reduced in CSF CD4+ cells. A biased Th1/Th2 balance may play a critical role in active inflammation and CCR5 on CSF CD4+ cells is a good marker of the disease activity.

High level expression of C4-specific NADP-malic enzyme in leaves and impairment of photoautotrophic growth in a C3 plant, rice

The chloroplastic NADP-malic enzyme (NADP-ME) is a key enzyme of the C4 photosynthesis pathway in NADP-ME type C4 plants such as maize. To express the chloroplastic NADP-ME in leaves of a C3 plant, rice, full-length cDNAs encoding the rice C3-specific isoform and the maize C4-specific isoform of the enzyme were expressed under the control of the rice CAB: promoter. Transformants carrying the rice cDNA showed the NADP-ME activities in the leaves less than several-fold that of non-transformants, while those carrying the maize cDNA showed activities up to 30-fold that of non-transformants or about 60% of the NADP-ME activity of maize leaves. These results indicate that expression of the rice C3-specific NADP-ME is suppressed at co- and/or post-transcriptional levels by some regulation mechanisms intrinsic to rice, while that of the foreign C4-specific isoform can escape from such suppression. The accumulation of the maize C4-specific NADP-ME led to bleaching of leaf color and growth hindrance in rice plants under natural light. These deteriorative effects resulted from enhanced photoinhibition of photosynthesis due to an increase in the level of NADPH inside the chloroplast by the action of the maize enzyme.

Paralytic shellfish toxins in the freshwater cyanobacterium Aphanizomenon flos-aquae, isolated from Montargil reservoir, Portugal

Montargil reservoir, located in a dry flat area in the centre of Portugal, was filled in 1958 to fulfil agricultural, electric and industrial requirements. In May 1996, an intensive bloom of phytoplankton was detected. The algal community was strongly dominated by cyanobacteria with predominance of Aphanizomenon flos-aquae from May to June and Microcystis aeruginosa from July to August. Extracts of samples collected during the bloom period showed high toxicity by mouse bioassay. During the M. aeruginosa predominance period, the toxicity was ascribed to the presence of hepatotoxins, but clear symptoms of paralytic shellfish poison were observed when A. flos-aquae was the dominant species. In order to confirm the production of neurotoxins a strain of A. flos-aquae was isolated and established in culture. In this manuscript, we show the morphological characteristics and confirm paralytic shellfish toxins production by the strain isolated and maintained in culture. Identification of the saxitoxin analogs was achieved using high performance liquid chromatography with postcolumn fluorescence derivatization (HPLC-FLD) and liquid chromatographic mass spectrometry technique (LC-MS). The toxins found in the culture extract were GTX5 (64.5 mol%), neoSTX (23.0 mol%), dcSTX (6.1 mol%), STX (5.4 mol%) and GTX6 (1.1 mol%). This is, to our knowledge, the first report of unambiguous evidence of paralytic shellfish toxins produced by freshwater cyanobacteria in Portugal. The toxin profile is rather different from the previously reported PSP producing A. flos-aquae and demonstrates its diversity in terms of toxin production.

Modifying effects of ethinylestradiol but not methoxychlor on N-ethyl-N-nitrosourea-induced uterine carcinogenesis in heterozygous p53-deficient CBA mice

It is unknown whether endocrine-disrupting chemicals (EDCs) with estrogenic activities have any modifying effects on uterine carcinogenesis. In our previous study, we established a uterine-carcinogenesis model that is useful for detecting tumor-modifying effects of EDCs by the administration of N-ethyl-N-nitrosourea (ENU) to female heterozygous p53-deficient CBA mice [p53 (+/-) mice]. To investigate the effects of ethinylestradiol (EE) and methoxychlor (MXC) on development of ENU-induced uterine tumors, female p53 (+/-) mice and their wild-type littermates [p53 (+/+) mice] received an intraperitoneal injection of 120 mg/kg body weight (bw) of ENU, followed, in Group 1, by no further treatment; in Group 2, by a diet containing 1 ppm EE; in Group 3, by a diet containing 5 ppm EE for 4 weeks and 2.5 ppm EE thereafter; and in Group 4, by a diet containing 2000 ppm MXC for 26 weeks. Uterine proliferative lesions that were induced were composed of both endometrial-stromal and epithelial-cell types. Endometrial stromal sarcomas were induced in p53 (+/-) mice of Groups 1 to 4, and the incidence (87%) in Group 3 was significantly increased compared to Group 1 (47%). Atypical hyperplasias (clear-cell type) of the endometrial gland in p53 (+/-) mice were seen at incidences of 0, 14, 60, and 0% in Groups 1, 2, 3, and 4, respectively, while their incidence in p53 (+/+) mice was 0, 7, 53, and 0%, respectively, with a significant difference between Groups 1 and 3 in both cases. One p53 (+/-) mouse in Group 3 also had an adenocarcinoma consisting of clear cells, and the PCNA labeling indices of the clear-cell atypical hyperplasias, and this endometrial adenocarcinoma, were higher than those of glandular hyperplasias. The present study suggests that 2.5 ppm EE, but not MXC, exerts tumor-promoting effects on stromal and epithelial proliferative lesions of the uteri in p53 (+/-) mice initiated with ENU.

Novel control system for blood glucose using a model predictive method

We developed a novel blood glucose control system, using a model predictive method, to achieve optimal control of the blood glucose level in severely diabetic or pancreatectomized patients. This system is designed to predict glucose level changes in advance, considering delayed response time and the administered doses of insulin. This method is also designed to calculate the most appropriate insulin infusion rate by considering differences in individual response to insulin. In this study, we compared our system with a conventional proportional and differential controller (PD controller) to determine whether the new system could regulate the glucose level efficiently in pancreatectomized dogs. The model predictive control method resulted in a significant reduction of mean insulin infusion rate compared with the conventional PD controller (0.71 mU/kg per min vs. 1.81 mU/kg per min, p = 0.0005), when the glucose level in both methods reached the planned target level (100 mg/dl). The new system also tended to have a reduced mean glucose infusion rate for compensating for overshooting of the glucose level compared with the PD controller (0.7 mg/kg per min vs. 1.1 mg/kg per min, p = 0.16). These results indicate that the new system should be a useful tool for regulating the glucose level in severely diabetic patients.

Anti-tetanus toxoid antibody production and protection against lethal doses of tetanus toxin in hu-PBL-SCID mice

BACKGROUND

In this study, severe combined immunodeficiency (SCID) mice, which permit the survival of lymphoid cells of human origin, were used to study the human anti-tetanus immune response.

METHODS

Human peripheral blood lymphocytes (hu-PBL) obtained from 88 healthy donors (aged from 18 to 62) were transplanted into SCID mice, and anti-tetanus toxoid (Ttd) antibody production and protection against lethal doses of tetanus toxin (Ttx) were investigated in the hu-PBL-SCID mice.

RESULTS

The transfer of human PBL evoked significant human anti-Ttd IgG antibody production for 37.5% of the donors. After in vivo immunization, the percentage of donors with PBL exhibiting positive anti-TtD IgG production in the mice increased to 54.5%. Mean anti-Ttd IgG levels in the sera were also significantly elevated in response to immunization. The mean IgG titer for the mice injected with PBL from donors under the age of 40 was significantly higher than that of the mice injected with PBL from donors aged 40 or older. Four weeks after the cell transfer, the mice were challenged with Ttx. The induction of protection against Ttx challenge was observed mostly in mice with PBL transferred from donors under the age of 40. In vivo immunization in SCID mice with Ttd increased the number of cases of resistance to Ttx.

CONCLUSIONS

These results suggest that hu-PBL-SCID mice might serve as a tool for predicting the protective ability against pathogens in PBL donors and also for evaluating vaccine efficacy.