Cystathionase: a potential cytoplasmic marker of hematopoietic differentiation

Abstract

Cysteine auxotrophy and absence of cystathionase (CSE) has been associated with certain human and rodent leukemic cell lines. To determine whether this state was a marker of malignant transformation or of cellular differentiation, CSE content was measured in 16 well characterized human leukemia-lymphoma cell lines. Enzyme was easily detected in several lines but its level did not correlate with a proposed scheme of differentiation based on cell-surface markers. However, the apparent absence of enzyme in human bone marrow CFU-C determined by growth experiments suggests reduced levels of CSE may be a marker of cytoplasmic immaturity.