Evidence for a mouse brain-specific variant of alpha-tubulin.

While studying the neural precursor cell intermediate filament protein known as nestin in the developing mouse brain, we observed a strong cross-reaction of our nestin antibody with a 50 kDa protein that appeared on embryonic day 10 and continued to accumulate until postnatal day 1. Here we report evidence that this protein is a brain-specific variant form of alpha-tubulin and discuss its implications.

The "recall effect" in radiotherapy: is subeffective, reparable damage involved?

It has been proposed that lethal mutations among the progeny of a surviving cell could be the basis for the recall effect when chemotherapy is applied subsequent to the repair of normal-tissue injury resulting from a course of radiation therapy. Because radiotherapy is usually multifractionated, the possibility exists that repair of heritable injury of this type could occur between fractions as is the case for sublethal damage. To examine this possibility, the endpoint small-colony formation was used--an endpoint which integrates the effects of a number of radiation-induced aberrancies including lethal mutations--and low-dose-rate irradiation. It was found that, even after net surviving fractions comparable to those sought in radiotherapy were reached, little damage remained expressible as a deficiency in the size of the colony generated from a surviving cell. We conclude that the damage expressible as a lethal mutation is reparable and therefore the recall effect must be attributed to some other cellular mechanism.

Separation of osteoblast-like cells from bone marrow by fluorescence-activated cell sorting.

The purification of the osteoblast-like cells (2-3%) among the bone marrow cells (BMC) of C57BL/6 mice using a specific anti-osteoblast serum and a fluorescence-activated cell sorter is described. The antiserum was raised against osteoblast cells isolated from calvaria from neonatal mice. The majority of the cells of the osteoblast-enriched fraction from bone marrow showed a parathormone-induced increase in cyclic adenine monophosphate but no response to calcitonin. This is similar to the response of osteoblast cells obtained from the calvaria. Electron microscopic studies of the extracellular matrix of cultured osteoblast-like cells purified from bone marrow showed the deposition of apatite crystals within and in close apposition to the vesicles. These findings suggest that the isolated cell population was enriched in osteoblasts. Such a cell system from bone marrow might provide an experimental system for investigating the mechanism of bone formation.

Efficiency of neural differentiation of mouse P19 embryonal carcinoma cells is dependent on the seeding density.

Serum-free culture conditions for retinoic acid-induced neural differentiation of mouse P19 embryonal carcinoma cells were determined for future ex vivo retroviral gene transfer and brain transplantation studies. Neural differentiation of P19 cells was dependent on the seeding densities, and both neurons and astroglia differentiated efficiently at high seeding densities (2 x 10(4) and 5 x 10(4) cells/cm2) but not at low seeding density (1 x 10(4) cells/cm2). In addition, P19 cells cultured at 5 x 10(4) cells/cm2 showed neural differentiated whether or not they were infected with Friend leukemia virus FrC6-V, which inhibited neural differentiation at 2 x 10(4) cells/cm2. These results indicate that FrC6-V-infected P19 embryonal carcinoma cells should be seeded at high density to achieve efficient neural differentiation in vitro for ex vivo gene transfer with a FrC6-V-derived retroviral vector system.

A possible role of the nestin protein in the developing central nervous system in rat embryos.

Rat embryos at the head-hold stage (Slc:SD strain; 9.5 days of gestation) were cultured for 48 h in rat serum with the anti-nestin peptide antiserum. The antiserum identified a single band in Western blots of the tissue extracts from rat embryos and stained the cells from the neural tube, migrating neural crest, and somites immunohistochemically. The antiserum-treated embryos appeared to develop normally for the most part. However, histological observation disclosed that the ventral portion of the neural tube was deformed. The cells in the deformed portion did not show the elongated shape but were round. These round cells tended to crowd near the ventricular surface, and a gap was observed between the original pial surface and cells arranged in the most pialward region. The penetration of the anti-nestin peptide antibody into the embryos from the culture medium was confirmed by visualization of the penetrated antibody using biotinylated anti-rabbit IgG antibody raised in goats and Texas red-conjugated streptavidin. These results indicate that the nestin protein plays an important role in the organization or the maintenance of neuroepithelial cells of the elongated shape spanning the neural tube from the luminar to the pial side.

Metabolism of 4-hydroxyaminoquinoline-1-oxide and its binding to DNA in chick embryos.

The metabolic pathway of 4-hydroxyaminoquinoline-1-oxide (4HAQO) and its binding to DNA was studied in 2-day chick embryos administered [G-3H]4HAQO in a shell-less culture. The 4HAQO rapidly metabolized into non-carcinogenic compounds and 1 h after administration only very small amounts of free 4HAQO could be detected in the embryo cells. The amount of DNA-bound 4HAQO in the embryo cells reached a maximum 2 h after administration, then began to decrease. The maximum extent (mu mol/mol P of nucleotide) was 18.2, equivalent to 1 molecule of 4HAQO-purine adducts per 2.8 X 10(4) base pairs of DNA. It was possible to detect removal of 4HAQO-purine adducts from DNA in chick embryo cells in a shell-less culture. A dose-response relationship for the killing effect of 4HAQO on 2-day embryos was observed in the range of 0.24-24 nmol 4HAQO per embryo. The practicality of the present method of administration of 4HAQO for 'flash administration' of compounds to chick embryo and the advantages of the shell-less culture method which provides access for biochemical and developmental studies of chick embryos were also discussed.

Preferential infection of neuronal and astroglia cells by Akabane virus in primary cultures of fetal bovine brain.

Akabane virus is a member of the genus Bunyavirus; it is pathogenic for ruminants and transmitted by arthropod vectors. Infection of adult cattle and sheep causes a transient viremia without obvious clinical signs, while infection of pregnant animals often causes fetal abnormalities including hydranencephaly, poliomyelitis and arthrogryposis. Infectious virus or viral antigens is present in the brain, spinal cord and skeletal muscle of infected fetuses. To understand the interaction between Akabane virus and bovine brain cells, we investigated the viral tropism using primary cultures of fetal bovine brain. The cultured neuronal cells, astroglia cells and microglia cells were distinguished by cell type specific antisera. Akabane virus was found to infect neuronal cells and astroglia cells, which led to degenerative death. No microglia cells were found infected. In some brain cultures, we observed different sensitivities of the cells to two Akabane virus strains: an attenuated strain infected and spread more readily than wild type virus. This difference was not observed in a hamster fibroblast cell line. Both viral and host determinants might be involved in the different susceptibility of brain cells to Akabane virus infection.

Isolation of a germline-transmissible embryonic stem (ES) cell line from C3H/He mice.

We have isolated three embryonic stem (ES) cell lines from C3H/He mice using mouse STO cells as a feeder layer. One ES cell line (H-1) was male, and two (H-2 and H-3) were female, as determined by polymerase chain reaction, in situ hybridization, and karyotype analyses. All were immunocytochemically reactive with a C3H strain-specific antibody. Injection of cells from the female ES H-3 line into C57BL/6 blastocysts yielded four chimeras with slight coat color chimerism. All chimeras were male, and as expected, no germline-transmission was observed. By contrast, when male ES H-1 cells were injected into the perivitelline space of 8-cell C57BL/6 embryos, one male mouse with overt coat color chimerism was recovered, and it produced ES H-1-derived offspring exclusively. This germline-transmissible C3H/He cell line represents a novel addition to those ES lines currently employed for gene manipulation studies of development.

Humoral and cellular immunity to Candida albicans in patients with bronchial asthma.

Delayed cutaneous reactivity to Candida albicans (C. albicans) and PPD (purified protein derivative) was examined in 52 patients with bronchial asthma in relation to the production of specific IgG4 antibodies against the antigen. 1. The frequency of a positive, immediate skin reaction to C. albicans was similar among the five age groups, ranging from 60.0% to 66.7%. 2. The incidence of a positive delayed skin reaction to C. albicans was lower in patients between the ages of 10 and 30 and tended to decrease with aging in the patients over the age of 51. 3. A delayed skin reaction to PPD was positive in patients between 31 and 50 with a higher incidence; this incidence decreased in patients over age 51. 4. The level of C. albicans-specific IgG4 antibodies was significantly higher (26.7 u/ml) in patients with a negative delayed skin reaction to the antigen than in those with a positive reaction (5.9 u/ml) (p less than 0.001). There was no correlation between delayed skin reaction to PPD and production of specific IgG4 antibodies.

A new modified classification of bronchial asthma based on clinical symptoms.

The clinical features of four asthma types, Ia-1 (bronchospasm with 0-49 ml/day of expectoration), Ia-2 (with 50-99 ml/day), Ib (over 100 ml/day), and II (bronchiolar obstruction), as classified by the clinical symptoms, were compared in 119 patients with bronchial asthma. The age of onset characteristic symptoms of each asthma type was in the 20's in types Ia-1 and Ia-2, in the 30's in type Ib, and in the 40's in type II patients. A significant increase in the number of neutrophils in bronchoalveolar lavage (BAL) fluid was found in type II patients. The proportion of BAL eosinophils was significantly higher in types Ia-2 and Ib asthma patients compared with that in type Ia-1 patients. The BAL eosinophil count was significantly higher in type Ib than in type Ia-2 patients. The FEV1.0% and %V25 values were significantly lower in patients with type II asthma than in the patients with the other asthma types. Steroid-dependent intractable asthma (SDIA) was more often observed in patients with type Ib or type II asthma.

Food-dependent exercise-induced anaphylaxis.

A 58-year-old farmer was admitted to our hospital because of repeated episodes of anaphylaxis. He had experienced 12 episodes of anaphylactic shock over the previous 17 years. These attacks included three episodes of bee sting. In general, the episodes occurred during farm work (exercise) and within two hours of eating cake in the afternoon. Because an immediate skin reaction to wheat flour was highly positive, a diagnosis of wheat allergy was considered. These findings suggested that his illness was consistent with food-dependent exercise-induced anaphylaxis.

Cellular composition of fluid in the airways of patients with house dust sensitive asthma, classified by clinical symptoms.

The cellular composition of bronchoalveolar lavage (BAL) fluid was observed in 28 patients with house dust mite-sensitive asthma. The proportion of neutrophils in the BAL fluid was significantly higher in the patients between the ages of 50 and 59 and those over 60 than in the patients younger than age 39. There was a significant difference in the number of neutrophils in patients aged 30-39 years and in those over 40 at the onset of disease. The cellular composition varied among the three types of asthma; the mean percentage of cells in the BAL fluid was 1.1% neutrophils and 21.3% eosinophils in type Ia (simple bronchoconstriction), 9.1% neutrophils and 23.0% eosinophils in type Ib (bronchoconstriction + hypersecretion), and 34.4% neutrophils and 12.0% eosinophils in type II (bronchiolar obstruction). The results suggested that an increased frequency of both neutrophils and eosinophils correlates with the mechanism of hypersecretion, and that a marked increase in the proportion of neutrophils is involved in bronchiolar obstruction.

Eosinophilic leucocytes and arylsulfatase activity in bronchoalveolar lavage fluid of patients with bronchial asthma.

The arylsulfatase activity and histamine concentration of bronchoalveolar lavage fluid (BALF) were examined in patients with bronchial asthma in relation to the eosinophil count and asthma type (atopic and non-atopic). The BALF arylsulfatase activity and histamine concentration were significantly higher in atopic asthmatics than in non-atopic asthmatics. In atopic asthmatics, the activity of arylsulfatase was significantly increased in patients with a higher eosinophil count (10% or more). However, the BALF histamine concentration did not correlate with the eosinophil count. In non-atopic asthmatics, there was no significant correlation between arylsulfatase activity and the eosinophil count. The results show that arylsulfatase participates in IgE-mediated allergic reactions.

Chemical mediator and cellular reaction in the bronchoalveolar lavage fluid of patients with steroid-dependent intractable asthma (SDIA).

The effects of long-term glucocorticoid therapy on chemical mediator and cellular reaction in the airways were examined in 69 patients with bronchial asthma. The histamine release induced by Ca ionophore A23187 from cells in the bronchoalveolar lavage (BAL) fluid of atopic asthmatics was significantly lower in the subgroup with steroid-dependent intractable asthma (SDIA) than in non-SDIA patients (p < 0.05). In contrast, histamine release in nonatopic SDIA patients did not differ from nonatopic non-SDIA patients. The release of leukotriene C4 (LTC4) was significantly lower in atopic patients with SDIA (p < 0.02). However, there was no significant difference in LTC4 release between nonatopic patients with SDIA and without SDIA. The proportion of BAL lymphocytes was significantly lower in atopic patients with SDIA than in those without it (p < 0.05), although there was no significant difference between the nonatopic patients with and without SDIA. These results show that glucocorticoids affect humoral and cellular events in the airways of atopic asthmatics more than in those of nonatopic asthmatics.

Cell-mediated immunity in bronchial asthma evaluated by purified protein derivative- and Candida albicans-skin reaction.

Cell-mediated immunity was examined in 45 patients with bronchial asthma by observing the delayed cutaneous reaction to purified protein derivative (PPD) and Candida albicans (C. albicans). The delayed skin reaction to PPD showed a decrease with age starting between 50 and 59 years old. The delayed reaction to PPD decreased more prominently with aging, being significantly depressed in the patients aged over 70 years than in those aged between 30 and 49 years (induration, p < 0.02; flare, p < 0.01). The C. albicans-induced skin reaction was significantly lower in the patients aged over 70 years than in those between 60 and 69 years old (induration, p < 0.01; flare, p < 0.05). The delayed skin reaction to PPD and C. albicans was significantly depressed in the patients with a serum IgE level over 1001 IU/ml. Delayed skin reaction to PPD and C. albicans was more depressed with aging and an elevated serum IgE, and the age (50-59 years) at the initiation of depression in the PPD-induced delayed skin reaction was younger than that (over 70 years) in the C. albicans-induced reaction.

Effect of a serum factor on IgE-mediated histamine release from whole blood.

IgE-mediated histamine release from whole blood was analyzed in 44 patients with bronchial asthma by observing maximum present release and dose-response curves of histamine release induced by anti-IgE and house dust extract. The maximum histamine release from whole blood induced by anti-IgE correlated with total serum IgE levels. There was a close correlation between allergen-induced release from whole blood and the serum levels of specific IgE antibodies. In the maximum histamine release from whole blood induced by both anti-IgE and allergen, the interaction with a serum factor was not clearly recognized. Effect of a serum factor was shown in the dose-response curves of anti-IgE-induced histamine release, but not in those of allergen-induced histamine release. The dose-response curves caused by anti-IgE showed that basophils from cases with a high serum IgE level require much more anti-IgE to produce maximum histamine release than basophils from cases with a low serum IgE level. The results showed that IgE molecules contained in the serum participate in anti-IgE-induced histamine release from whole blood.

Comparison of basophil histamine release induced by the cross-linking of IgE receptors.

Basophil histamine release induced by allergens (house dust and Candida albicans) and anti-IgE was examined in 31 patients with bronchial asthma in relation to patient age, age at onset of the disease and serum IgE levels. Basophils from patients under 40 years of age generally released a significantly large amount of histamine by stimulation with house dust and anti-IgE. On the other hand, histamine release from patients over 41 years of age was generally not marked when the cells were incubated with house dust and anti-IgE, although, in some cases, the release induced by C. albicans was fairly marked. Basophils from patients under 30 years of age at onset were reactive to house dust and anti-IgE, while the cells from patients over 41 years of age at onset tended to be reactive only to C. albicans. Basophils from patients with low serum IgE levels were less reactive than the cells from patients with high levels of IgE to house dust and anti-IgE. C. albicans-induced release of histamine did not correlate with serum IgE levels.

Spa therapy improves ventilatory function in the small airways of patients with steroid-dependent intractable asthma (SDIA).

The improvement of ventilatory function by spa therapy was examined in 37 patients with steroid-dependent intractable asthma (SDIA) in relation to clinical asthma types. All subjects had been on long-term corticosteroid therapy before spa therapy. Spa therapy was found to improve the values of ventilatory parameters. The percent improvement in all subjects was +4.1% in %FVC, +8.9% in FEV1.0%, +9.8% in %PEFR, +22.0% in %MMF, +19.7% in %V50 and +28.2% in %V25, respectively. Relating to clinical asthma types, moderate improvement in %MMF and %V25 from 16.7% to 16.9% was observed in type Ia cases, and marked increase in %MMF, %V50 and %V25 was observed from 42.2% to 43.2% in type Ib cases. However, no significant increase was found in these parameters of types Ia or Ib after spa therapy. In patients with type II, a significant increase was shown in %V50 (p less than 0.05) and %V25 (p less than 0.01) after spa therapy. The results show that spa therapy improves the condition of small airways disorder in patients with SDIA.

Asthma classification by pathophysiology and IgE-mediated allergic reaction: new concepts for classification of asthma.

Bronchial asthma was classified by the pathophysiology and by the mechanism of onset of the disease. Forty asthmatics who had serum IgE levels lower than 200 IU/ml were evaluated by two classification methods. 1. In asthma classified by a score based on clinical findings and examinations, the characteristics of the findings and examination results were compared among three asthma types, i.e., Ia. simple broncho-constriction type, Ib. bronchoconstriction+hypersecretion type, and II. bronchiolar obstruction type. Type Ib patients, in addition to manifesting hypersecretion, had a significantly higher proportion of eosinophils in the bronchoalveolar lavage (BAL) fluid compared to other asthma types. Significantly decreased values for ventilatory parameters and an increased proportion of BAL neutrophils were found in type II compared with other asthma types. 2. In a new classification by mechanism of onset, asthma was classified into three types according to the degree of participation of IgE-mediated reactions associated with specific IgE antibodies and serum levels of total IgE: asthma induced by definite IgE-mediated reaction (atopic asthma), possible IgE-mediated reactions (asthma), and asthma induced by non-IgE-mediated reaction (asthma syndrome).

Blood eosinophilia in bronchial asthma and its relationship to IgE-mediated reactions.

The correlation between blood eosinophilia and anti-IgE-mediated histamine release was investigated in 22 bronchial asthma patients with peripheral eosinophilia (over 8%). In the cases (Group A-1 and Group A-2) in which house dust was the specific antigen, significant histamine release from basophils was induced by anti-IgE and house dust. The result indicates a relationship between eosinophilia and the IgE-mediated mechanism of disease onset. In the cases (Group A-3) with RAST scores of 0+ and 1+ to house dust, the anti-IgE-induced histamine release varied from low to high percentages, and the participation of the IgE-mediated pathway was indicated in some cases. In the cases (Group B) with negative skin reactions, few patients had a family history of allergic disease. Their ages at onset were higher, and they demonstrated lower total IgE levels. These cases showed an extremely low percent of histamine release from basophils, which indicated the absence of a correlation between eosinophilia and IgE-mediated mechanisms.