ULTRASTRUCTURE OF ALS TRANSFORMED LYMPHOCYTES

The ultrastructure of human lymphocytes cultivated in vitro in the presence of horse anti-human lymphocyte serum was observed from the 1st to the 5th day of incubation. The nuclear morphology of the transformed cells is that of lymphoid or young lymphoreticular nuclei, with multiple stages of differentiation. The cytoplasmic morphology of the transformed cells is characterized by an abundance of polysomes and mitochondria; it never resembles that of a plasmocyte, The ATPase-like activity of the cytoplasmic membranes of the transformed cells is concentrated on the microvillosities. Cells transformed by ALS and by PHA have an identical ultrastructure. © 1969.