| Autor: |
Giovanni Neri, Sylvia C. Capetillo, Earl F. Walborg, J.J. Starling |
| Rok vydání: |
1977 |
| Předmět: |
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| Zdroj: |
Experimental Cell Research. 104:177-190 |
| ISSN: |
0014-4827 |
| DOI: |
10.1016/0014-4827(77)90080-5 |
| Popis: |
Rat liver cells were isolated by two techniques: perfusion with citrate followed by mechanical dispersal and enzymatic dissociation by perfusion with collagenase. The viability and ultrastructural integrity of the enzymatically dispersed cells were superior to those dissociated mechanically. Hepatocytes prepared by mechanical dispersal were not agglutinated by high concentrations of concanavalin A (ConA) or wheat germ agglutinin (WGA), whereas hepatocytes isolated by the enzymatic method were agglutinated by both lectins and exhibited a significant increase in their agglutinability after treatment with papain. These data indicate that cell viability and/or structural integrity are required for ConA- or WGA-induced agglutination of rat hepatocytes. A non-dialyzable sialoglycopeptide fraction cleaved from the cell surface by digestion with papain was isolated from enzymatically dispersed hepatocytes and Novikoff ascites hepatoma cells. These sialoglycopeptide fractions were further purified using gel filtration (Sephadex G-50). Comparison of their gel filtration profiles and lectin receptor activities revealed significant qualitative differences between the cell-surface sialoglycopeptides of normal and malignant rat liver cells. The most prominent cell-surface sialoglycopeptide fraction from hepatoma cells was excluded from the gel and possessed the major portion of the lectin receptor activity, whereas the most prominent cell-surface sialoglycopeptide fraction from hepatocytes was partially accessible to the gel and possessed no detectable ConA or WGA receptor activity. These data indicate that papain-labile cell-surface sialoglycopeptides are not involved in the ConA- and WGA-induced agglutination of intact rat hepatocytes and that, in contrast to Novikoff hepatoma cells, ConA and WGA receptor sites are not released by papain digestion of the intact hepatocytes. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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