Tenascin-C is required for proliferation of astrocytes in primary culture.

Astrocytes in primary culture can be classified morphologically into two types: fibrous astrocytes and protoplasmic astrocytes. To examine the role of tenascin-C (TN) in an in vitro astrocyte culture, primary cultures of astrocytes prepared from the brains of wild-type and of TN-deficient embryonic mice were analyzed. In primary culture of astrocytes from TN-deficient mice fibrous astrocytes did not appear and astrocytes did not become tile-shaped when they came in contact with each other. The rate of 5-bromo-2'-deoxyuridine incorporation in a cell proliferation assay was much lower for astrocytes from TN-deficient mice than for astrocytes from wild-type mice. These results suggest that TN is an essential molecule for maintaining the proliferation and proper morphology of astrocytes in primary culture.