STUDY OF CHRONIC LYMPHOCYTIC-LEUKEMIA CELLS BY FT-IR SPECTROSCOPY ANDCLUSTER-ANALYSIS

The peripheral mononuclear cells from 23 normal individuals and the pu rified B cells from 38 patients with chronic lymphocytic leukemia (CLL ) were examined by Fourier transform infrared (FT-IR) spectroscopy. Di fferences were observed between the CLL and normal cells at the DNA, p rotein and lipid levels, with CLL cells having greater DNA and lower l ipid contents than normal cells. In addition, the spectral character o f the CLL and normal cells varied, demonstrating that there were also qualitative differences in the DNA and lipids. Statistical analysis, b ased on hierarchical clustering, separated normal from CLL cells compl etely and classified them into two subgroups for normal cells, while t he CLL cells could be divided into three subgroups that were distinct from the normal cells. These differences were based on the lipid and D NA content and the overall spectral character of the cells. Copyright (C) 1996 Elsevier Science Ltd.