Ultrastructural changes of leukemic cells treated with antileukemic agents.

Part 1. Ultrastructural studies of mouse L1210 cells (ascites form).

Abstract

Ultrastructures of transplantable L1210 leukemic cells (ascites form) were investigated. Cells grown intraperitoneally in BDF₁mice were used. Cells obtained by centrifugation of ascites were fixed in aldehyde and/or osmium tetroxide, and processed for ultrastructural observation. Occasionally an in situ, phosphotungstic acid (PTA) staining was performed.
L1210 cells (8∼23.5μin diameter), round to oval, possess centrally located, chromatinrich nucleus having quite compact nucleolus. Glycocalyx is not well developed. In the cytoplasm lipid inclusions, often in close contact with mitochondria or endoplasmic reticulum, are frequently observed. The rough-surfaced endoplasmic reticulum is scanty, however, free ribosomes are rich. Mitochondria, often irregularly-shaped, show clear matrix and few cristae. In some areas the presence of intramatricial DNA-fibril (nucleoid) and ribosome-like particles is evident. The Golgi apparatus, lysosomes, multivesicular bodies, coated vesicles, filaments, microtubules, and tubules can also be observed. Virus particles, strongly positive for PTA, are observed in the cisternae of endoplasmic reticulum, the perinuclear space, the cytoplasmic matrix and the extracellular space.