Behavior and Function of Lymphocytes in Relation to Their Basic Nuclear Units

Abstract

.I his paper records a discovery of basic, pa;tially independent nuclear units that lie within a common nuclear ~nernbrane of some vertebrate cells. The cells concerned are found in series from small (1-2 p) to large (10-15 p or more). The smallest cells possess one basic nuclear unit, the larger cells have several. The series of cells fro~n small to large represent stages of a life cycle. Certain of the basic nuclear units act as reproductive organelles and certain large cells are parent cells producing new small cells thus closing one life cycle and startlng another. 'I'he large cells are forrncd from the small cells through a series of fusions. 'I'he basic nuclear units behave similarly to ruicron~~clci, the reproductive organelles in ciliates, but the fusions of the vertebrate cells are permanent, not temporary unions such as conjugation in ciliates.The discovery of the basic nuclear units and their role in the lile cycle of some vertebrate cells has given rise to a new concept of blood cell cytogenesis. The inclivitlual chromatin lumps characteristic of the nuclei of lymphocytes are founcl to be separate entities, the basic nuclear units upon which bloocl cell cytogenesis depends.The small Ij,mphocyte (4-6p) is found to be the ltey cell in reproductio~i of bloocl cells. Two small lymphocytes move together and establish close contact. The contact becomes permanent as a projection of nucleoplasin that extends out from each of them joins forming an internuclear bridge. As soon as contact is made between the two cells their basic iluclear ini its begin a series of divisions that increase the number of units but decrease their incliviclual sizes. These clivisions eventually leacl to formation of nexv cells.

Morphology of Blast Cell Nuclei in Vivo and in Vitro

“…At times they resemble giant or polytene chromosomes (3, Fig 27). A t other times each BNU divides into small granular chromosomes (3,Figs 19,20), and sonletimes the senior author has seen BNU's display small very fine hair-like chromosomes. I n the two latter cases each BNU behaves as an individual nucleus going through regular mitotic stages.…”