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K Wasano

Publications and source records attributed to K Wasano.

15 recordsLinked to original sources

Morphological heterogeneity of secretory granules of rat Clara cells: an immunocytochemical study.

The secretory granules of rat bronchiolar Clara cells were classified into different types by their ultrastructural appearances followed by immunocytochemistry using anti-rat 10 kDa Clara cell-specific protein (10 kDa CCSP) antibody. One predominant type was the oval to round granule (type A granule), of which the matrix was composed of a map-like mixture of electron-dense and less electron-dense material. Another predominant type was the rod-shaped granule (type B granule). The content of type B granules varied from a finely fibrillar (type B1 granule) to an electron-dense, rod-like (type B3 granule) structure. Various intermediate types (type B2 granule) between type B1 and B3 granules were also found. Small cytoplasmic vesicles were found occasionally in close proximity to type B2 or B3 granule. Another type of granule (type C granule) was large, up to 8 microns in diameter, and contained a moderately electron-dense amorphous matrix. Both type A and C granules stained at a similar density with the antibody. The nascent form of type A granules, which was found in the vicinity to the trans face of the Golgi apparatus, was also labeled. On the other hand, the labeling density of type B granules varied: type B1 granules were almost devoid of immunolabeling, whereas type B3 granules were intensely labeled. Type B2 granules stained with the antibody; however, the labeling density was less than that of type B3 granules. The small cytoplasmic vesicles of type B2 granules were labeled.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals

Immunolocalization of 67 kDa elastin-binding protein in perinatal rat lungs.

67 kDa elastin-binding protein (RL-67EBP) has been isolated from neonatal rat lungs by the use of an elastin-coupled affinity column, followed by elution with either lactose or synthetic elastin hexapeptide (VGVAPG), and immunohistochemistry has been used on perinatal rat lungs to determine the tissue localization of this protein. No immunoreactive structures occur in fetal lungs, or in the lungs of day-1 and -4 neonates. On day-7 after birth, immunoreactive cells appear in the subepithelial connective tissue of the intrapulmonary airways, from day-10 on, these cells become evenly distributed in the alveolar parenchyma. Occasionally, some cells occur in the alveolar air space, being free from the surface of the alveolar septum. Unpermeabilized cells obtained by bronchoalveolar lavage, show cell surface immunoreactivity, indicating that RL-67EBP is expressed on the surface membrane of the cells. From these findings, it is suggested that the immunoreactive cells are blood-borne monocytes, and that RL-67EBP may function as an elastin peptide receptor by which monocytes mobilize through interstitial connective tissue during their migration from blood to alveolar air space, where they eventually differentiate into alveolar macrophages.

Animals

Immunohistochemical localization of 14 kDa beta-galactoside-binding lectin in various organs of rat.

Immunohistochemical localization of 14 kDa beta-galactoside-binding lectin in various organs of adult rat was achieved using a monospecific antibody raised against lectin purified from rat lung. The antibody-stained cells were formed into small aggregates, thin fascicles, or thick bundles in the walls of blood vessels, gastrointestinal tracts and urogenital organs. From the patterns of distribution, as well as their organization, these immunoreactive cells were regarded as smooth muscle cells. This was confirmed by a double immunofluorescence study using a mixture of anti 14 kDa lectin and anti alpha-smooth muscle-specific actin antibodies. Strong 14 kDa lectin immunoreactivity was seen in the pericellular matrix of smooth muscle cells in intact organs as well as in detergent-treated organs from which all cellular components were extracted. From these findings, it is suggested that the 14 kDa lectin may be externalized by smooth muscle cells into their pericellular matrix and participate in the crosslinking of the complementary glycoconjugate(s) localized at that site. The macromolecular xomplex of glycoconjugates thus formed around smooth muscle cells may play a role in anchoring smooth muscle cells to the pericellular connective tissue thereby permitting the force of muscle contraction to be efficiently transmitted to the surrounding connective tissue proper.

Animals

Immunoelectron microscopic analysis of Ia antigen expression in rat skin during limb allograft rejection.

Using a whole-limb graft model in rats, morphologic changes and variations in the expression of Ia antigen on epidermal cells were investigated in the allografted skin during acute rejection. BN right limbs were transplanted to F344 recipients. Skin tissues were excised during acute rejection on days 1, 3, 5, 7, and 9 after the transplantation. Sections were examined for Ia antigen expression using immunohistologic techniques, and in situ quantification of Ia antigen was made using an immunogold method. Epidermal keratinocytes expressed Ia antigen before the grafts were rejected and the amount of Ia antigen expression increased and exceeded the amount of Ia antigen of Langerhans cells during the course of rejection. The progressive increase in class II antigen expression on EKs correlated with the appearance and relative accumulation of dermal lymphocytic cells. On the other hand, Ia antigen was not expressed on vascular endothelial cells during rejection. Our results suggest that the Ia-positive keratinocytes can serve as target cells in skin rejection of limb allografts. The immunogold technique we used seems most pertinent for a quantitative examination of cell-surface antigens in situ.

Animals

Rat lung 29 kD beta-galactoside-binding lectin is secreted by bronchiolar Clara cells into airways.

We isolated a mixture of beta-galactoside-binding lectins from rat lung and raised polyclonal antibody against 14 kD lectin purified from the mixture of lectins. Immunoblotting of the mixture of lectins, which was separated with SDS-PAGE under reducing condition and transferred onto a NC paper, showed that the antibody reacted with two bands at 14 and 29 kD, indicating that these two lectins have common antigenic determinants(s). Immunohistochemically, the antibody recognized only bronchiolar Clara cells with intense immunofluorescence in their apical cytoplasmic protrusions where the secretory granules of the cells are known to be stored. Thus, to determine if the lectin(s) might be secreted into airways, we next raised antibody against airway secretions free from serum as well as surfactant proteins. By immunoblot analysis, the resulting antibody stained 29,45 and 55 kD bands, but not 14 kD band, on a NC paper transferred with the mixture of lectins. These findings suggest that at least 29 kD lung lectin is located in bronchiolar Clara cells and secreted by these cells into airways.

Animals

Lectin-gold cytochemistry of mucin oligosaccharide biosynthesis in Golgi apparatus of airway secretory cells of the hamster.

To elucidate the mechanism for the biosynthesis of O-linked mucin oligosaccharides, airway secretory cells of the hamster trachea were embedded in Lowicryl K4M resin, and sections were examined by lectin-gold cytochemistry with special attention focused on the Golgi apparatus. The interrelations between the Golgi cisternae stained with five different lectins were determined by double-staining procedures using various combinations of lectins conjugated with 14-nm and 8-nm colloidal gold. Several cis cisternae were stained only with HPA (Helix pomatia agglutinin specific for terminal alpha-N-acetylgalactosamine). The next medial cisternae were not stained with HPA, but reacted positively with two lectins, GSII (Griffonia simplicifolia agglutinin II specific for terminal alpha- or beta-N-acetylglucosamine) and RCAI (Ricinus communis agglutinin I specific for beta-galactose). The trans cisternae as well as condensing and mature secretory granules were labeled with four lectins, UEAI (Ulex europaeus agglutinin I specific for terminal alpha-L-fucose) and LFA (Limax flavus agglutinin specific for terminal N-acetyl or N-glycolyl neuraminic acid) in addition to HPA and RCAI. The same number of trans cisternae were positive to HPA and UEAI, whereas LFA bound to a few transmost cisternae but fewer than were stained with HPA or UEAI. The observed sequential appearance of different sugar residues in different levels of Golgi cisternae (from cis to trans cisternae) coincides quite well with the sugar sequence of airway mucin oligosaccharide (from reducing to nonreducing ends) proposed by biochemical analysis. It is suggested that airway mucin oligosaccharides elongate during a vectorial movement through the Golgi stack from cis toward trans and that the stack consists of at least three functionally distinct segments, cis, medial, and trans; in these three segments there take place, respectively, the initial O-glycosylation of mucin core peptide, the formation of a core region of oligosaccharide chain, and the completion of chain growth by addition of terminal sugar moieties.

Animals

Characterization of extended primary and secondary cultures of hamster tracheal epithelial cells.

Studies on the regulation of differentiation in airway epithelial cells have been hampered by the lack of cell culture systems that differentiate in vitro. One such system that does exhibit differentiation is hamster tracheal epithelial cells (HTE). A major problem with this system, however, is that at the time cells differentiate, they lyze the collagen gel upon which they grow, resulting in termination of the culture. Here we report that by growing the HTE cells at 32 degrees instead of 37 degrees C we can totally prevent lysis of the collagen gel. Cells grown at this lower temperature maintain their differentiated phenotype as evidenced by abundant mucus granules and the secretion of authentic mucus glycoproteins into the culture media. We have also developed a method for subculturing the primary cells which allows growth and differentiation in secondary culture. The HTE cells were capable of being passaged at least three times and did not become transformed as judged by their inability to grow in soft agar and to produce tumors in syngeneic animals. This improved HTE cell culture system will allow detailed studies on the mechanisms which regulate growth, differentiation, and mucus secretion in surface airway epithelial cells.

Animals

Membrane differentiation markers of airway epithelial secretory cells.

We describe here a system for culturing epithelial cells isolated from hamster trachea, which results in a highly enriched population of mucus-secreting cells. The culture system has enabled us to study the process of secretory cell differentiation in vitro. We found that epithelial secretory cells, in vivo and after 5 days in vitro, selectively bind the lectin Helix pomatia agglutinin (HPA) to apical and, to a lesser extent, basolateral surfaces as well as to mucin granules and intracellular secretory organelles. SDS-PAGE gels of detergent extracts of secretory cells cultured for 5 days reveal three HPA-binding glycoproteins with MW of 120 KD, 220 KD, and greater than 400 KD. The high-MW glycoprotein appears identical to mucin, since it is found in secretions from intact trachea and in spent media from 5-day cultures. It does not appear in spent media from 3-day cultures when cells contain few mucous granules and secrete little mucin. The 220 KD HPA-binding glycoprotein is also present in 5-day but not in 3-day cultures. In contrast, the 120 KD glycoprotein is present at both times. HPA-gp120 is a hydrophobic integral membrane protein, whereas HPA-gp220 and mucin are hydrophilic and are membrane associated. These studies define three membrane glycoproteins, one of which is specific for the tracheal epithelial secretory cell regardless of its mucous content, whereas the other two glycoproteins correlate with mucin secretion. They also demonstrate that, in the fully differentiated state, mucin is bound in a non-covalent fashion to the apical plasma membrane of the tracheal epithelial secretory cell.

Animals

Human neutrophil elastase releases cell surface mucins from primary cultures of hamster tracheal epithelial cells.

Primary hamster tracheal epithelial cells growing on a collagen gel matrix produce high molecular weight mucins indistinguishable from mucins produced in vivo. Using a modified version of these confluent cultures, we have demonstrated here that (i) release of mucins can be stimulated by human neutrophil elastase (HNE; EC 3.4.21.37); (ii) HNE can degrade mucins, and both mucin release and degradation by HNE require an active catalytic site; and (iii) there are at least two pools of mucins in these cells: one is a rapidly turning-over spontaneously releasable constitutive pool, the other is a slowly turning-over HNE-releasable pool. We provide evidence that the HNE-releasable mucins are membrane bound and associated with the secretory cell apical surface.

Animals

Microthread-like filaments connecting the epithelial basal lamina with underlying fibrillar components of the connective tissue in the rat trachea. A real anchoring device?

The structural relationship between the basal lamina and the underlying reticular tissue was studied, with special attention to the relationship among basal lamina-associated anchoring fibrillar (AF) arcs (Kawanami et al. 1978, 1979) and other fibrillar components, in the epithelium-denuded trachea of the rat. Quantitative analysis of a large number of AF arcs reveals that the majority of the AF arcs has no other fibrillar components of passage. This suggests that most AF arcs do not serve as a real anchoring device, connecting the basal lamina with the underlying reticular tissue, as has so far been suggested by Kawanami et al. (1978). Ruthenium-red staining reveals the presence of a unique meshwork of microthread-like filaments connecting the undersurface of the basal lamina or the AF arcs with the underlying fibrillar components with a remarkable continuity, suggesting that the filaments act as a real anchoring device; these filaments link, instead of the AF arcs, the basal lamina, to the subjacent reticular tissue. Various enzymatic treatments of the filaments indicate that their chemical nature is probably non-collagenous (glyco)protein without glycosaminoglycan moieties.

Animals

Three-dimensional architecture of elastic tissue in early atherosclerotic lesions of the rat aorta.

The overall three-dimensional architecture of elastic tissue in early atherosclerotic lesions of the rat aorta was studied using scanning electron microscopy (SEM) after hot-formic acid extraction followed by a freeze-drying method. These lesions were induced by feeding the rats a diet containing 2% cholesterol, 0.5% cholic acid and 0.2% methylthiouracil. SEM revealed two types of alterations in the elastic tissue; one was an increase in the dome-like elastic lamina with few fenestrations that might be due to the reduplication of the internal elastic lamina (IEL), and the other was an increase in fibrous elastin, generally oriented longitudinally in the intima. The former was discussed with respect to its barrier function to such macromolecules as fibrinogen and low density lipoprotein (LDL), and was assumed to be a structure related to prevention of early atherosclerotic lesions.

Animals

APUD-type recepto-secretory cells in the chicken lung.

The epithelium of the intrapulmonary airways of the chicken lung has been studied by fluorescence and electron microscopy. Numerous intensely yellow-fluorescent cells occur in the epithelium of the primary and secondary bronchi. The cell cytoplasm contains characteristic granular vesicles with an electron-dense central core. The vesicles react positively to chromaffin and argentaffin treatment, indicating that they are possible storage sites for amines. Synapse-like junctions occur between the granular cells and the intraepithelial nerve endings, filled with numerous mitochondria, suggesting that these granular cells may have a dual function as both receptor and endocrine cell.

APUD Cells

Monoamine-containing granulated cells in the frog lung.

The epithelium of the primary bronchus of the frog lung has been studied by fluorescence and electron microscopy. Clusters of five to ten, ovoid, brilliantly yellow fluorescent cells were observed in the basal portion of the epithelium. These cells contained numerous electron-dense granules of variable shape and size. The granules gave a positive argentaffin reaction at the ultrastructural level, suggesting a possible existence of monoamines in the granules. In addition, synaptic contact between the intraepithelial nerves and the cells, which was characterized by the aggregation of the granules toward the presynaptic membrane thickening of the cell, was also noted. These data are discussed in relation to similar studies in birds and mammals, and a possible function of these cells suggested.

APUD Cells

Neuro-epithelial bodies in the lung of the rat and the mouse.

Histochemical and ultrastructural examinations were performed on neuroepithelial bodies (N. E. B.) in the lung of the mouse and rat. The N. E. B. were identified as specialized groups of pale, columnar cells. They were located throughout the intrapulmonary airway. These cells displayed some special cytochemical properties also seen in the APUD (Amine Precursors Uptake and Decarboxylation) endocrine system, such as cytoplasmic argyrophilia and the capability of selective uptake of amine precursors. Ultrastructrally the N. E. B. were composed of a kind of granulated cell which had concentrations of specific cored vesicles in the basal cytoplasm. It seemed likely that the cells released the contents of the cored vesicles into the extracellular space by exocytosis. These cells made extensive and intimate contact with the mitochondria-rich nerve terminals which occurred mainly at the level of the supranuclear portions of the granulated cells. In this contact area, the membrane of the nerve terminals were apposed to that of the granulated cells with a consistent gap of about 20 nm. Among these membrane appositions, some membrane thickenings were observed in which cored vesicles were closely associated in the granulated cell cytoplasm. From these observations, it was conceived that the lung N. E. B. function both as receptor and endocrine organs and that their specific cored vesicles may have an intimate correlation with these dual functions.

APUD Cells