1. degree of chromatin condensation with clumping of the heterochromatin in the vicinity of the nucleolus. The Golgi apparatus was poorly developed, and all the cells had only limited profiles of endoplasmic reticulum. Most cells contained a variable number (1-36/cell section) of localised electron dense inclusions, which, invariably, were surrounded by a membrane (Fig. 2). Often several inclusions of different sizes were surrounded by the same membrane, which did not appear to have any association with Golgi cisternae or the endoplasmic reticulum
2. The inclusions were seen in close association with small, medium density granules in 40% of cells; in some cells the inclusions seemed to have divided the granules (Fig. 3) The inclusions ranged in size from
3. The granules that were often seen in association with the inclusions also showed acid phosphatase reactivity (Fig. 5). Variable reactivity of the inclusions with anti-;x o'. SRat, S.; positive
4. Although both the globular and crystalline structures noted in B chronic lymphocytic leukaemia have been shown to consist of immunoglobulin,69 12-18 the nature of the inclusions described in B prolymphocytic leukaemia is uncertain. Costello et al reported an acid phosphatase positivity of some of the inclusions,20 and Kjeldsberg et al noted that the inclusions were concentrated in the Golgi zone,22 and on the basis of those findings a lysomal origin was suggested. Although some of the inclusions seen in the present case were in close association with lysosomal granules and were mainly localised in the perinuclear area, they were, nevertheless, acid phosphatase negative and were also randomly distributed throughout the cell. Thus the lysosomal origin of the inclusions could not be confirmed
5. Multiple plasma cell myeloma with crystalline deposits in the tumour cells and in the kidneys;Neuman, V.;Journal of Clinical Bacteriology,1949