Abstract
Microspectrophotometric comparison of lymphocyte nuclei and free L.E. bodies which are derived from them show a more than twofold average increase in the latter of protein basic groups revealed by naphthol yellow S binding, and tyrosine residues demonstrated by the Millon reaction. The alkaline fast green method for histones and the Sakaguchi reaction for arginine residues suggest that there is a marked loss and ultimate disappearance of histones in the course of formation of the L.E. body from a nucleus. It is postulated that the L.E. transformation entails influx of protein normally foreign to the nucleus, displacement of histone from combination of DNA, and association of the DNA with the new protein which is then responsible for masking the anionic groups of DNA.