Heat-induced radial segmentation of leucocyte nuclei: a non-specific phenomenon accompanying inflammatory and necrotizing diseases.

Heat-induced radial segmentation (RS) of leucocyte nuclei in vitro (2 h at 41 degrees C) is a heretofore unknown phenomenon, accompanying inflammatory and necrotizing diseases. This phenomenon appears to be identical with the known oxalate-induced radial segmentation and is caused by contractile microfilaments and microtubuli radiating from the centriole. Preincubation of washed leucocytes from healthy donors with plasma of patients showing the phenomenon of RS did not induce RS and preincubation of washed RS-leucocytes with normal plasma did not suppress RS. RS, however, could be induced by intravenous endotoxin injection in a healthy volunteer and could be prevented in part by addition of Vincristine to the blood samples. The phenomenon corresponds to an incomplete, heat-inducible amitosis. The cause of the thermolability of the mitotic apparatus in various diseases remains unclear.