Lowering Cholesterol With Granulocyte-Macrophage Colony-Stimulating Factor-Reply

In Reply.—  We appreciate the comments of Dr Goldstein and Drs Mazur and Herbert regarding our recent report in JAMA. We have data available on changes in low-density lipoprotein and high-density lipoprotein (HDL) cholesterol concentrations in five of the eight patients reported (Table). In three of these patients HDL-cholesterol decreased slightly, but in all instances the decrease in HDL-cholesterol was proportionally less than the decrease in low-density lipoprotein cholesterol, resulting in a lower low-density lipoprotein/HDL cholesterol ratio. In one of the patients HDL-cholesterol levels increased during GM-CSF therapy and in the other patient there was no real change in HDL-cholesterol levels. The low-density lipoprotein/HDL cholesterol ratios decreased in all patients, a favorable direction in considering the possible treatment or prevention of atherosclerosis with GM-CSF or other factors that use similar mechanisms.Our findings are indeed preliminary, but we are actively exploring the mechanism of action of GM-CSF's cholesterollowering activity. As