Inability of Japanese rubella vaccines to induce antibody response in rabbits is due to growth restriction at 39° C

Summary We have compared the kinetic growth patterns of To-336, MEQ₁₁, KRT, and SK₂ rubella vaccine strains licensed in Japan at 37° and 39° C with those of progenitor wild strains of rubella virus. The growth of vaccine strains was depressed at 39° C to a level about 3 log₁₀ lower than that at 37° C. The difference in virus titer attained by wild strains at 37° and 39° C was less than tenfold. The growth potential at 39° C paralleled the immunogenic marker of rubella virus,i.e. the capability of virus to induce antibody response upon subcutaneous injection in rabbits for all wild and vaccine strains examined, including one strain at an intermediate level of attenuation. Several clones were isolated from the progeny produced by a vaccine strain during the growth at 39° C. Among them were partial revertants in immunogenic marker as well as in the growth potential at 39° C. It was concluded that the immunogenic marker of rubella virus in rabbits represented its capability to replicate at the body temperature of the animal.With 6 Figures     

Elevated nasal mucosal G protein levels and histamine receptor affinity in a guinea pig model of nasal hyperresponsiveness

BACKGROUND: Nasal hyperresponsiveness is a common feature of allergic rhinitis, but the underlying mechanisms have yet to be elucidated. The effects of repeated antigen inhalation on the characteristics of histamine H(1) receptors and expression levels of heterotrimeric guanosine 5'-triphosphate-binding proteins in nasal mucosa were investigated to understand the mechanisms of the pathogenesis of nasal hyperresponsiveness in allergic rhinitis. METHODS: Male Hartley guinea pigs were sensitized by the inhalation of dinitrophenylated ovalbumin antigen (10 mg of protein/ml) and repeatedly challenged by inhaling aerosolized dinitrophenylated ovalbumin antigen for 3 weeks. Twenty-four hours after the last antigen inhalation, in vivo nasal responsiveness to histamine was measured. [(3)H]Mepyramine binding assays and immunoblotting for alpha subunits of the G(q) protein were also performed using membrane preparations of isolated nasal mucosae. RESULTS: The histamine-induced increase in intranasal pressure was significantly augmented after repeated antigen challenge, indicating that nasal hyperresponsiveness was achieved. In saturation binding studies, no significant change was observed in the density and antagonist affinity of H(1) receptors in the hyperresponsive animals. On the other hand, the affinity of histamine for high-affinity agonist binding sites in the hyperresponsive group, measured by histamine competition binding studies, was much greater than that in control animals, and these results were affected by guanosine 5'-O-(3-thiotriphosphate) in both groups. Moreover, Galpha(q) levels in nasal mucosal homogenates were significantly increased after repeated antigen challenge. CONCLUSIONS: Elevated G protein levels in nasal mucosa might induce an increased binding affinity of histamine to its receptors, resulting in an augmented nasal response to histamine, that is, nasal hyperresponsiveness, in guinea pigs.     

Effect of NMDA receptor antagonist on proliferation of neurospheres from embryonic brain

The N-methyl-D-aspartate (NMDA) receptor, a subtype of ionotropic glutamate receptors, plays an important role in the regulation of neuronal development, learning and memory, and neurodegenerative diseases. NMDA receptor blockade enhances neurogenesis in the hippocampal dentate gyrus in vivo. The effect of NMDA receptor antagonist on proliferation of neural progenitor cells, however, remains to be determined. We investigated changes in the diameter and number of neurospheres derived from the embryonic rat brain after NMDA receptor blockade. Cortical progenitor cells were isolated from gestational day 18 fetal rats according to the Percoll density gradient method. Cultured spheres expressed neural progenitor markers, musashi-1 and nestin. Immunohistochemical analysis demonstrated that cells in Dulbecco's modified Eagle medium/F12 containing 1% fetal bovine serum on day 8 differentiated to MAP-2-positive neurons and GFAP-positive astrocytes. The expression of NR1 and NR2B subunits of the NMDA receptor in neurospheres was detected. Neither brief nor sustained exposure to NMDA altered the diameter and number of neurospheres. Brief exposure to 30 μM MK-801, an NMDA receptor antagonist, decreased the diameter of neurospheres. Sustained exposure to 30 μM MK-801 decreased the diameter and number of neurospheres. Our results provide evidence that MK-801 directly decreased proliferation of neural progenitor cells.     

Helicobacter pylori seropositivity and IL-1B C-31T polymorphism among Japanese Brazilians

We reported previously that anti-Helicobacter pylori antibody seropositivity (HP+) had an association with interleukin 1B (IL-1B) C-31T genotype, especially among smokers. This study examined the association for Japanese Brazilians. In this cross-sectional study, voluntary participation was announced through Japanese Brazilian communities in Sao Paulo, Curitiba, Mogi das Cruzes, and Mirandopolis; 963 Japanese Brazilians (399 males and 564 females) aged 33-69 years participated. Lifestyle data and peripheral blood were collected. An anti-HP IgG antibody test and genotyping for IL-1B C-31T and IL-1RN 86 bp VNTR were independently conducted. The genotype frequency of the IL-1B polymorphism among 947 individuals was 23.9% for C/C genotype, 45.6% for C/T genotype, and 30.5% for T/T genotype. Sex-age-adjusted odds ratio (aOR) of HP+ was 1.30 (95% confidence interval, 0.94-1.81) for C/T genotype and 1.45 (1.02-2.07) for T/T genotype relative to C/C genotype. The aOR for 127 current smokers was 2.45 (0.91-6.55) for C/T and 3.49 (1.17-10.46) for T/T, while that for 667 never smokers was 1.21 (0.82-1.78) and 1.36 (0.90-2.05), respectively. The corresponding figures were 2.42 (1.16-5.02) and 3.00 (1.33-6.78) for 226 current drinkers, and 1.21 (0.82-1.78) and 1.36 (0.90-2.05) for 667 non-drinkers. The difference in the OR was observed for milk consumption, salty pickled vegetable eating, and physical exercise practice. 4/4 Genotype of IL-1RN 86 bp VNTR was 84.8%, and had no association with the HP seropositivity. The observed association between HP+ and IL-1B -31TT indicated that the genetic trait also influences the susceptibility to HP for Japanese in Brazil.     

Primary ovarian angiosarcoma: A case report and literature review

Primary ovarian angiosarcoma is extremely rare. Only 16 cases have histologicaliy been reported to date In the Ilterature. A case of angiosarcoma arising In the right ovary of a 46-year-old female is presented. Grossly, the resected right ovary was completely replaced by a solid tumor mass, which revealed multiple necrotic and/or hemorrhagic foci. This case revealed the typical histological features of angiosarcoma with sinusoldal and solid patterns of anaplastic tumor cells. Immunohlstochemically, tumor cells were strongly and diffusely positive for CD31 and CD34, in particular, along the cytoplasmic membrane of the tumor cells. Ultrastructurally, tumor cells possessed the intermediate junctions between tumor cells, discontinuous basal laminae attached to the irregularly shaped blood vessels and occasional cytoplasmic pinocytotlc vesicles. These findings confirmed the case as being one of angiosarcoma of the ovary. The patient died 9 months after surgery as a result of developed multlfocal brain metastases. A total of 17 cases reported as primary ovarian anglosarcoma, including this presented case, are clinicopathologically reviewed.     

In vivo labeling of amyloid with BF-108

Detection of aggregated amyloid-beta (Abeta) with a non-invasive imaging modality such as positron emission tomography (PET) was suggested to be ideal for the diagnosis of Alzheimer's disease (AD) prior to the onset of clinical symptoms. We have been searching for imaging probe candidates with a high affinity for aggregated Abeta in vitro and in vivo and high lipophilicity, a characteristic that allows for the permeation of the blood-brain barrier (BBB). As analyzed by Thioflavin T (ThT) assay and octanol/water partition coefficient test (PC), 3-diethylamino-6-(2-fluoroethyl)ethylaminoacridine (BF-108) were found to have high affinity for Abeta aggregates in vitro and high lipophilicity. Intravenously administrated BF-108 labeled Abeta aggregates injected into the amygdala as observed under a fluorescence microscope, showing this compound's permeability of BBB and an ability to label Abeta in vivo. BF-108 also labeled neuritic senile plaques (SPs), neurofibrillary tangles, and amyloid-laden vessels in temporal and hippocampal sections from AD patients. Following intravenous administration of BF-108 to an APP23 transgenic (TG) mouse, in vivo labeling of endogenous plaques was seen in brain sections by fluorescence microscopy. These properties suggest the potential utility of BF-108 for in vivo imaging of AD pathology.     

Characterization of factor XII Tenri, a rare CRM-negative factor XII deficiency

Factor XII Tenri (Y34C), a rare cross-reacting material (CRM)-negative factor XII deficiency, was identified in a 71-yr-old Japanese woman with angina pectoris. In the patient's plasma, factor XII activity and antigen levels were only 1.6% and 5.0%, respectively, of those seen in a normal subject. Immunoblot analysis showed that the secreted factor XII Tenri existed not only as a monomer (76 kDa), but also in complexes with apparent molecular weights of approximately 115, 140, 190, 215, and 225 kDa. After reduction with 2-mercaptoethanol, the factor XII Tenri contained in the complexes was completely converted to monomeric form on immunoblot patterns. It appeared that some of the secreted factor XII Tenri formed several types of disulfide-linked complexes, including a factor XII-alpha1-microglobulin complex, through a newly generated Cys residue. The monomeric form of factor XII Tenri, like normal factor XII, was degraded into 2 major fragments with molecular weights of approximately 45 kDa and 30 kDa following mixing with activated partial-thromboplastin-time measuring reagent (cephalin and ellagic acid), whereas the factor XII Tenri that formed the complexes was not. This indicates that the factor XII Tenri present in disulfide-linked complexes with other proteins (and itself) is not converted to active forms, suggesting that attached proteins obstruct or delay the activation of factor XII via an inhibition of its binding to a negatively charged surface in vitro.     

Dietary nucleic acid and intestinal microbiota synergistically promote a shift in the Th1/Th2 balance toward Th1-skewed immunity

BACKGROUND: Intestinal microbiota are known to play an important role in the establishment of oral tolerance, thereby protecting the organism from food allergies. Dietary intake of nucleic acid (NA) is also reported to have such an anti-allergic effect; however, one unsolved question is whether or not dietary NA would act through a process of toll-like receptor 9 signaling activated by DNA containing a CpG motif, a well-known sequence leading to immunostimulatory activity. In this study, we focused on the question of whether the addition of dietary NA lacking CpG motifs would allow continued modulation of the Th1/Th2 balance. METHODS: Germ free (GF) and Bifidobacterium-infantis-monoassociated BALB/c mice were maintained on either an NA-free casein diet or on an NA-supplemented casein diet for 4 weeks. Thereafter, both the in vivo anti-casein antibody levels and in vitro splenocyte cytokine secretion pattern were evaluated. RESULTS: Feeding with a casein diet elicited a substantial increase in the serum anti-casein-specific IgG1, IgG2a, and IgE levels of GF mice fed the NA free-diet. The in vitro cytokine production profile showed that enhanced IL-4 production in the GF mice fed the NA free-diet was markedly reduced by the supplementation with dietary NA in both the GF and B.-infantis-monoassociated mice. In addition, IFN-gamma secretion increased in the B.-infantis-reconstituted mice fed the diet containing NA. CONCLUSIONS: These results suggest that dietary intake of NA devoid of CpG motifs may prevent the development of allergies via acceleration of Th1-dominant immunity.     

Morphological study of disordered myelination and the degeneration of nerve fibers in the spinal cord of mice lacking complex gangliosides

Gangliosides, a family of glycosphingolipids that contain sialic acid, are abundant on the neuronal cell membranes, but their precise functions in the central nervous system remain largely undefined. In a previous study of GalNAc-T(-/-) mice engineered to lack beta1,4-N-acetylgalactos-aminyltransferase (GM2/GD2 synthase) to abolish any, complex gangliosides, we observed the reduction of nerve conduction velocity but did not find any obvious morphological change in the brain. In the present study, we observed morphological changes in the nerve fiber tracts of the spinal cord in these mice. In GalNAc-T(-/-) mice, the number of degenerated axons was markedly increased in the dorsal funiculus, tract of Lissauer, and dorsolateral funiculus of the cervical segment of the spinal cord as well as the dorsal funiculus and tract of Lissauer of the lumbar segment of the spinal cord. There were also increased numbers of unmyelinated fibers in GalNAc-T(-/-) mice. Loosened myelin sheaths and myelin sheaths separated from axons by wide spaces were also observed in GalNAc-T(-/-) mice. These results provide a morphological basis for the previously observed reduction in the nerve conduction velocity and suggest that complex gangliosides are essential for the maintenance of myelin and the integrity of nerve fibers of the spinal cord.