Reduced levels of fibronectin in ataxia-telangiectasia lymphoblastoid cells.

In this study Epstein-Barr virus-transformed lymphoblastoid cells were shown to contain fibronectin. A marked difference in the number of fibronectin-positive cells was observed in control and ataxia-telangiectasia lymphoblastoid cells. Three control cell lines varied between 60% and 80% in the number of cells containing fibronectin. Only a small percentage of ataxia-telangiectasia cells (1-5%) had fibronectin present. Control and ataxia-telangiectasia fibroblasts had similar amounts and distributions of fibronectin. An asymmetric distribution of fibronectin was evident in many control and ataxia-telangiectasia lymphoblastoid cells. The increased frequency of fibronectin-containing cells in the control populations cannot be accounted for by different growth rates or variation in the various phases of the cell cycle in the two cell types.