Phospholipid and cholesterol differences amongst leukemic cell types with special reference to hairy cell leukemia: a...

Whole cell cholesterol and phospholipid content was determined for ten patients with hairy cell leukemia (HCL) and 15 patients with chronic lymphocytic leukemia (CLL). Malignant cells from HCL patients contained 0.412 mumol/10(8) whole cells is compared to 0.177 mumol/10(8) whole cells for CLL cells; the total phospholipid concentrations were 0.746 and 0.469 mumol/10(8) whole cells respectively (p less than 0.001). Phospholipid sub-types were determined by thin-layer chromatography. The percentages of sphingomyelin (HCL-16.2%, CLL-8.2%) and phosphatidylcholine (HCL-46.0%, CLL-55.1%) differed significantly between the two diseases (p less than 0.05, respectively). The novel finding in our study is that HCL cells are enriched two- to three-fold in sphingomyelin (expressed on a mumol/g protein basis) at the expense of phosphatidylcholine when compared to Cll cells (a PC/SM ratio of 2.9 in HCL compared to 6.5 in CLL). Increases in the total amount of cholesterol and phospholipid as well as in the selective portions of the individual phospholipids could reflect and, possibly, result in the unique membrane architecture of the hairy cell.