Striking deposition of toxic eosinophil major basic protein in mucus: implications for chronic rhinosinusitis.

Background: The mechanisms by which eosinophilic inflammation damages the epithelium and contributes to recurrent acute exacerbations in chronic rhinosinusitis (CRS) have not been fully elucidated.

Objective: We tested the hypotheses that eosinophils deposit toxic major basic protein (MBP) in the mucus and that MBP reaches concentrations able to damage the sinonasal epithelium.

Methods: Tissue specimens with mucus attached to the tissue were carefully collected from 22 patients with CRS and examined by using immunofluorescence staining for MBP.

Human aortic valve calcification is associated with an osteoblast phenotype.

Background: Calcific aortic stenosis is the third most common cardiovascular disease in the United States. We hypothesized that the mechanism for aortic valve calcification is similar to skeletal bone formation and that this process is mediated by an osteoblast-like phenotype.

Methods And Results: To test this hypothesis, we examined calcified human aortic valves replaced at surgery (n=22) and normal human valves (n=20) removed at time of cardiac transplantation.

Centrin-2 is required for centriole duplication in mammalian cells.

Background: Centrosomes are the favored microtubule-organizing framework of eukaryotic cells. Centrosomes contain a pair of centrioles that normally duplicate once during the cell cycle to give rise to two mitotic spindle poles, each containing one old and one new centriole. However, aside from their role as an anchor point for pericentriolar material and as basal bodies of flagella and cilia, the functional attributes of centrioles remain enigmatic.

Atorvastatin inhibits hypercholesterolemia-induced cellular proliferation and bone matrix production in the rabbit aortic valve.

Background: Despite the common occurrence of aortic stenosis, the cellular causes of the disorder are unknown, in part because of the absence of experimental models. We hypothesized that atherosclerosis and early bone matrix expression in the aortic valve occurs secondary to experimental hypercholesterolemia and that treatment with atorvastatin modifies this transformation.

Methods And Results: To test this hypothesis, we developed an experimental hypercholesterolemic rabbit model.

Immunomagnetic separation reagents as markers in electron microscopy.

Antibodies coupled to magnetic particles have been employed for immunomagnetic cell isolation, but their consequent use for electron microscopy (EM) has not been evaluated. We used commercial antibodies coupled to iron-dextran to isolate T cells and monocytes/macrophages by immunomagnetic adsorption from normal human peripheral blood mononuclear cells. Subsequently, we studied the association of electron-dense immunomagnetic reagents with cell membranes.

Localization of caveolin 1 in aortic valve endothelial cells using antigen retrieval.

Ultrastructural analysis of aortic valve endothelial cells subjected to growth arrest revealed many vesicles defined as caveolae by the localization of caveolin. Translocation of caveolin after exposure to oxidized LDL suggests that the localization of caveolin may be a valuable tool to study models of early atherogenesis. In this study, several antigen retrieval protocols were tested in osmium-fixed and Spurr-embedded cells to determine the optimal method of antigen retrieval in our model system.