Spindle bridge and mid-body in cultured lymphocytes.

By G. F. SMITH, HELGA KOLB AND JANET A. FAur’ cii DURING AN ELECTRON-MICROSCOPIC INVESTIGATION of cultured human lymphocytes, an intercellular or spindle-bridge and mid-body were observed (Figs. 1 and 2). These unusual structures occur in late telophase of cell division. While they have been demonstrated by electronmicroscopy in mammalian secondary spermatocytes,’ cnidoblasts of Hydra,2.3 rat erythroblasts4 and HeLa cells,5 their occurrence in cultured human lymphocyte cells has not been previously noted. This report describes a useful way of obtaining large numbers of cultured lymphocytes in various stages of growth for electron-microscopy. In addition, observations on the structure and composition of the spindle bridge and midbody in cultured human lymphocytes are presented.