Retinoblastoma Y79 cell line: a study of membrane structures.

The continuous retinoblastoma cell line Y79, grown in suspension culture, has been examined by transmission and scanning electron microscopy, including freeze-fracture replica preparations. Four classes of cells were distinguishable by their size and surface characteristics. The surface structures included blebs, filopodia, lamellipodia, microvilli, and microplicae. The possible origin of a most unusual type of cell, apparently forming natural clones, is discussed.