An ultrastructural and experimental study on the development of tubular structures in the lysosomes of Gaucher cells.

Characteristic storage inclusions of Gaucher cells contain numerous tubular structures and are demonstrated enzyme-cytochemically to be transformed secondary lysosomes. Tubular structures are composed mainly of twisted multilayers and partially of flat layers with or without twisting. Glucocerebroside extracted and purified biochemically from the Gaucher spleen resembles these flat layers. Therefore, the flat layers are considered to be a fundamental fine structural unit of the tubular structures made by crystallization of glucocerebroside molecules. The tubular structures are observed by electron microscopy to be formed in the digestive process of blood cells, especially erythrocytes, in the lysosomes of Gaucher cells. In one culture experiment, monocytes obtained from Gaucher patients developed tubular structures in the phagolysosomes after ingesting heat-denatured erythrocytes and became Gaucher cells. In the other culture experiment, monocytes were also transformed into Gaucher cells by taking up tubular structures added to the culture medium. Thus, both the intralysosomal formation of tubular structures in the macrophages and their ingestion of extracellular tubular structures released from other Gaucher cells seem essential for the development of Gaucher cells.