A serial section study of nuclear pockets containing nuclear material.

A serial section study of leukaemic lymphocytes was carried out to elucidate the three dimensional morphology of nuclear pockets containing nuclear material and their mode of genesis. From this and a previous study on nuclear pockets containing cytoplasmic material we conclude that these are two distinct lesions each with its own mode of genesis and one does not evolve from the other. Hence we propose that the common nuclear pocket containing cytoplasmic material be designated 'type I nuclear pocket' and the nuclear pocket containing nuclear material as the 'type 2 nuclear pocket'. Our serial section study also showed that some type 2 nuclear pockets are open, (i.e. there is continuity between the material in the pocket and the contents of the nucleus) while others are closed (i.e. the material in the pocket is completely separated from the material in the nucleus). At times one sees profiles suggesting that small satellite nuclei occur in leukaemic cells. Our serial section studies show that such profiles can be produced by fortuitous sections through type 2 nuclear pockets.