Abstract
Heat-induced radial segmentation (RS) of leukocyte nuclei in vitro (2 h at 41.degree. C) is a previously 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 leukocytes from healthy donors with plasma of patients showing the phenomenon of RS did not induce RS, and preincubation of washed RS-leukocytes with normal plasma did not suppress RS. RS could be induced by i.v. 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.