Focal adhesion kinase as a mechanotransducer during rapid brain growth of the chick embryo.

Expansion of the hollow fluid-filled embryonic brain occurs by an increase in intraluminal pressure created by accumulation of cerebrospinal fluid (CSF). Experiments have shown a direct correlation between cavity pressure and cell proliferation within the neuroepithelium. These findings lead us to ask how mechanistically this might come about.

Chitosan nanoparticles as a potential drug delivery system for the ocular surface: toxicity, uptake mechanism and in vivo tolerance.

Purpose: To study the in vitro and in vivo interaction of chitosan nanoparticles (CSNPs), a new particulate drug carrier, with epithelial cells on the ocular surface.

Methods: CSNPs labeled with fluorescein isothiocyanate-bovine serum albumin were produced by ionotropic gelation. Human conjunctival epithelial cells (IOBA-NHC) were exposed for 15, 30, 60, and 120 minutes to three different CSNP concentrations.

Alpha2-adrenergic receptors are present in normal human conjunctiva.

Purpose: Despite the passage of medications, including antiglaucoma drugs, through the ocular surface, and despite the increasing relevance of neurogenic inflammation in the ocular surface, the presence of some neuroreceptors in the conjunctiva has not been ascertained. This study describes the presence of alpha2-adrenergic receptors in normal human conjunctiva.

Methods: Immunofluorescence microscopy, electrophoresis, and Western blot analyses were done in human conjunctival biopsies and rat control tissues.

Characterization of a spontaneously immortalized cell line (IOBA-NHC) from normal human conjunctiva.

Purpose: To characterize a new nontransfected, spontaneously immortalized epithelial cell line from normal human conjunctiva (IOBA-NHC), both morphologically and functionally, to determine whether the differentiated phenotype of conjunctival epithelial cells is preserved.

Methods: Outgrowing cells from explanted conjunctival tissue were successively passaged and preliminarily characterized at passage 3 to assess epithelial origin. The cells were further characterized at passages 15 to 20, 40, 60, and 100 by analyzing (1) proliferation and in vitro behavior (viability, plating efficiency, colony forming efficiency and colony size, and Ki-67 protein expression), (2) karyotype and G-banding, (3) epithelial marker expression (cytokeratins, desmoplakins, EGF receptor), (4) absence of contaminating cell types, (5) expression of conjunctival differentiation markers (mucin gene expression), and (6) functional capability in response to proinflammatory stimuli.