Hideya Wataya

Mechanism of neutrophil recruitment induced by IL-8 in chronic sinusitis

BACKGROUND The mechanism of neutrophil recruitment in patients with chronic sinusitis is unclear. OBJECTIVE This study aims to elucidate the role of IL-8 in inducing neutrophil accumulation in the nasal discharge of patients with chronic sinusitis. METHODS Nasal discharge and mucosal specimens were obtained from two groups of patients, those with chronic sinusitis and those with allergic rhinitis. The samples were subjected to immunohistochemical examination and in situ hybridization. The IL-8 level in the nasal discharge was measured by enzyme immunoassay. RESULTS Immunoreactivity to IL-8 was observed in polymorphonuclear cells of nasal smear, in nasal gland duct cells, and in epithelial cells of the chronic sinusitis group; whereas those of the allergic rhinitis group mostly showed little or no reaction. Similar patterns of localization were shown by in situ hybridization for IL-8 messenger RNA. The IL-8 level in nasal discharge was significantly higher in the chronic sinusitis group than in the allergic rhinitis group. CONCLUSION These results suggest that chemotactic factors in sinus effusion, including IL-8 derived from nasal gland duct cells and epithelial cells, attract neutrophils out of mucosa, and the neutrophils that have emigrated into the sinus effusion secrete IL-8. This induces further neutrophil accumulation in the sinus effusion of patients with chronic sinusitis.

Quantitative carbohydrate analyses of the tectorial and otoconial membranes of the guinea pig

Carbohydrate composition of the tectorial membrane (TM) and the otoconial membrane (OM) of the guinea pig was analyzed after hydrolysis, using high-performance anion-exchange chromatography and pulsed amperometric detection. Both of the tissues were highly glycosylated; the carbohydrate content being 24-42% of protein. GlcN, Gal, Glc and Man were found to be the major component sugars of TM, whereas little GalN was found. Fuc and NANA were also present, but NGNA was not detectable. After digestion with thermolysin for solubilization, OM was separated into two fractions: insoluble mineral particles of the otoconia (OM-ppt) and a soluble fraction from the gelatinous layer (OM-sup). These two fractions showed distinct carbohydrate composition from each other. Further analyses using glycosidases revealed that TM contained asialyl and monosialyl but little di-, tri- and tetrasialyl N-glycosides, and OM-sup did not seem to be susceptible to endo-beta-galactosidase, which is known to cleave some N-acetyl-polylactosamine and keratan sulfate. Based on these analyses, it can be suggested that most of the carbohydrates in TM are likely to be asialyl and monosialyl N-glycosides. N-Glycosides may be predominant in the otoconia as well, and a polymer structure consisting of GlcN(Ac) and Gal other than N-acetyl-polylactosamine may exist in the gelatinous layer of OM. O-Glycosylation of the usual type appeared to be minor in all the fractions.

Localization of Nerve Growth Factor Receptor in Developing Inner Ear of Rats

NGFR-immunoreactivity was first detected in the epithelia of the otic placode at E 10 and the entire epithelium of the otic vesicles was NGFR-immunoreactive at E 11. At this stage no nerve fibers were present in the epithelia and the immunoreactivity was confined to portions of the otic epithelium where the immunoreactive nerve bundles penetrated. As the development proceeded and the organ of Corti was matured, NGFR-immunoreactivity was localized on the plasma membrane of intraepithelial nerve fibers, that of adjacent epithelial cells apposed to the nerve fibers, and apical microvillous membrane of the supporting cells directly apposed to the hair cells. The occurrence of NGFR-immunoreactivity in the otic epithelial cells from early stages of development suggests that NGFR in the epithelia might provide a means to concentrate NGF on the cells which would become the substratum for growing nerve fibers in development. Furthermore, the specific appearance of NGFR-immunoreactivity in the apical microvillous membrane of the maturing supporting cells implies that NGF secreted into the endolymph from somewhere in the otic epithelia may exert some, yet to be defined effects on the supporting cells in the maturation of the organ of Corti.

The Differentiation of Polyps and Their Mucosal Ultrastructure

This paper reported both ultrastructural and biochemical studies of nasal polyps from 32 patients: 5 with an aspirin-induced asthma; 14 allergic patients with rhinitis; and 13 nonallergic patients with negative skin tests against the major inhalant allergens. The results of the studies have clearly shown that there are two different types of nasal polyps, neutrophil-dominant polyps and eosinophil-dominant polyps, and both leukocytes play a major role as important effector cells in the formation of nasal polyps. Cytotoxic effector molecules from both leukocytes initiate the connective tissue damage of the capillary basement membrane, bringing about enormous tissue edema, with broad disruptions of the epithelial lamina, causing polyp formation.