Isolation of a hemidesmosome-rich fraction from a human squamous cell carcinoma cell line.

Hemidesmosomes are cell-to-matrix adhesion complexes anchoring keratinocytes to basement membranes. For the first time, we present a method to prepare a fraction from human cultured cells that are highly enriched in hemidesmosomal proteins. Using DJM-1 cells derived from human squamous cell carcinoma, accumulation of hemidesmosomes was observed when these cells were cultured for more than 10 days in a commercial serum-free medium without supplemental calcium. Electron microscopy demonstrated that numerous electron-dense adhesion structures were present along the basal cell membranes of DJM-1 cells cultured under the aforementioned conditions. After removing cellular materials using an ammonia solution, hemidesmosomal proteins and deposited extracellular matrix were collected and separated by electrophoresis. There were eight major polypeptides, which were determined to be plectin, BP230, BP180, integrin α6 and ß4 subunits, and laminin-332 by immunoblotting and mass spectrometry. Therefore, we designated this preparation as a hemidesmosome-rich fraction. This fraction contained laminin-332 exclusively in its unprocessed form, which may account for the promotion of laminin deposition, and minimal amounts of Lutheran blood group protein, a nonhemidesmosomal transmembrane protein. This hemidesmosome-rich fraction would be useful not only for biological research on hemidesmosomes but also for developing a serum test for patients with blistering skin diseases.

[The effects of si-wu-tang on serum protein of blood deficient mice induced by radiation].

OBJECTIVE: To study the effects of Si-Wu-Tang on serum protein of blood deficient mice b y proteomicstechnique and study the enriching and regulating blood mechanism of Si-Wu-Tang on mocular level. METHOD: The blood deficient mice was induced by using a single dose of 3.5 Gy radiation from a 60Cogamma source, and high resolution two-dimensional polyacryamide gel electrophoresis (2-DE), computer-assisted image analysis, and mass spectrometry were used to detect regulated protein by Si-Wu-Tang. RESULT: 12 lower and 4 higher protein in sera could be recovered by Si-Wu-Tang, 4 protein might be DNA-dependent protein kinase catalytic subunit, Dystrophin, KIF13A, dystonin. They play a part in DNA double-stranded break repair, recombination and modulation of transcription, transportation of mannose-6-phosphate receptor, etc. CONCLUSION: Si-Wu-Tang can regulate serum protein in blood deficient mice, resulting in improving hematopoiesis and lessening irradiated injury.

The effects of si-wu-tang on serum protein of blood deficient mice induced by radiation / 中国中药杂志

<p><b>OBJECTIVE</b>To study the effects of Si-Wu-Tang on serum protein of blood deficient mice b y proteomicstechnique and study the enriching and regulating blood mechanism of Si-Wu-Tang on mocular level.</p><p><b>METHOD</b>The blood deficient mice was induced by using a single dose of 3.5 Gy radiation from a 60Cogamma source, and high resolution two-dimensional polyacryamide gel electrophoresis (2-DE), computer-assisted image analysis, and mass spectrometry were used to detect regulated protein by Si-Wu-Tang.</p><p><b>RESULT</b>12 lower and 4 higher protein in sera could be recovered by Si-Wu-Tang, 4 protein might be DNA-dependent protein kinase catalytic subunit, Dystrophin, KIF13A, dystonin. They play a part in DNA double-stranded break repair, recombination and modulation of transcription, transportation of mannose-6-phosphate receptor, etc.</p><p><b>CONCLUSION</b>Si-Wu-Tang can regulate serum protein in blood deficient mice, resulting in improving hematopoiesis and lessening irradiated injury.</p>

Effect of vitamin A deficiency on the adhesion of rat corneal epithelium and the basement membrane complex.

PURPOSE: To understand the underlying mechanisms responsible for the easy removal and sloughing of corneal epithelium in vitamin A deficiency. METHODS: An animal model of vitamin A deficiency, the vitamin A-deficient rat (A-rat), transmission electron microscopy, computer-assisted morphometric analysis and indirect immunofluorescence were used to study the adhesion of rat corneal epithelium to its basement membrane with emphasis on structure and molecular composition of the anchoring structures such as the hemidesmosome and bullous pemphigoid antigen. RESULTS: Transmission electron microscopy resolved numerous microseparations of the basal epithelial cell membrane from the basement membrane with intervening segmental basement membrane duplications and electron dense deposits. Morphometric analysis disclosed a statistically significant reduction in the frequency and size of hemidesmosomes. Four weeks after supplementing the diet with retinyl acetate (700 micrograms/week), significant reversal of these same structural abnormalities could be detected. Immunofluorescence staining for bullous pemphigoid antigen, a component of the adhesion complex, showed intense staining of the basal epithelial cytoplasm but weak and discontinuous staining of the basement membrane. Weak staining for laminin was also evident in A- corneas. In contrast, normal corneas displayed no cytoplasmic staining for bullous pemphigoid antigen and intense staining of the basement membrane for bullous pemphigoid antigen and laminin. CONCLUSIONS: The authors propose that structural abnormalities of the epithelial basement membrane complex are responsible for the observed loose epithelial adhesion and sloughing, as well as other known abnormalities of healing in the vitamin A-deficient rat cornea.