Effects of hyperosmotic stress on cultured airway epithelial cells.

Inhalation of hyperosmotic solutions (salt, mannitol) has been used in the treatment of patients with cystic fibrosis or asthma, but the mechanism behind the effect of hyperosmotic solutions is unclear. The relation between osmolarity and permeability changes was examined in an airway cell line by the addition of NaCl, NaBr, LiCl, mannitol, or xylitol (295-700 mOsm). Transepithelial resistance was measured as an indicator of the tightness of the cultures.

A modified technique for the impregnation of lanthanum tracer to study the integrity of tight junctions on cells grown on a permeable substrate.

Ionic lanthanum is commonly used to trace permeability pathways across epithelia and endothelia in biological electron microscopy. A method for obtaining a uniformly dense precipitate of lanthanum is described. The method, which is a modification of the technique described by Shaklai and Tavassoli (1977) was suitable for fixation of cell cultures grown on permeable filter inserts and was successfully applied to study opening of tight junctions by hypertonic solutions in the airway epithelial cell line 16HBE14o(-).

Prostasomes are secreted from poorly differentiated cells of prostate cancer metastases.

Background: Prostasomes are small (40-500 nm), granule-like bodies, found in normal epithelial cells of the prostate and secreted into the prostate duct system. Also poorly differentiated prostate cancer cells are producing prostasomes, since we could isolate and purify prostasomes from vertebral metastases with biochemical methods. To find out whether these prostasomes are secreted into extracellular sites of the metastases, we used electron microscopy.

Uptake of ovalbumin-conjugated starch microparticles by pig respiratory nasal mucosa in vitro.

The uptake of ovalbumin-conjugated starch microparticles (OVA-MP) was studied after application to porcine respiratory nasal mucosa in vitro. Nasal mucosa from freshly slaughtered pigs was mounted in horizontal Ussing chambers, which permit monitoring of the viability of the tissue exposed to microparticles and ensure that the microparticles are deposited on the mucosa. The antigen-conjugated starch microparticles have previously been shown to produce strong mucosal, cellular and systemic immune responses to conjugated model antigens following oral administration.

Ultrastructure of the secretion of prostasomes from benign and malignant epithelial cells in the prostate.

Background: Prostate epithelial cells are producing, among other things, a fluid secretion containing small bodies, the prostasomes. The mechanism of synthesis of the prostasomes is not known in details, neither is it known whether the mode of prostasome production changes at a neoplastic transformation of the prostate cells. Due to the small size of the prostasomes, we have used electron microscopy for evaluating the production and distribution of prostasomes in benign and neoplastic cells of the prostate.