Expression of proliferation and differentiation antigens in response to modulation of membrane fluidity in chronic lymphocytic leukemia lymphocytes.

Isolated lymphocytes from patients with chronic lymphocytic leukemia (CLL) and from healthy controls were investigated for cell membrane fluidity and lipid phase separation. Expression of surface immunoglobulins, OKB7 and HLA-DR antigen, transferrin and interleukin-2 receptor was determined in relation to modulation of membrane lipid composition in each individual case. Structural and functional changes of membrane lipids and impaired lipid-protein interactions could be demonstrated in CLL lymphocytes. However, there is no simple correlation of membrane fluidity and receptor expression. This interaction poses a complex physicochemical problem, which must consider the original structural and functional state of the lipid bilayer. Disturded lipid-protein interactions are discussed in terms of defective transmembrane signalling and cell-cell interaction, allowing uncoupling of the leukemic cell from the network of growth and differentiation factors.