In vivo effects of IL-4, IL-10, and amifostine on cytokine production in patients with acute myelogenous leukemia

Both IL-4 and IL-10 have been shown in vitro to inhibit leukemia cell secre tion of IL-1 beta, GM-CSF, and TNF alpha, and increase leukemia cell releas e of IL-1ra. In this study, we have investigated the in vivo effects of IL- 4, IL-10, and amifostine on cytokine production in patients with acute myel ogenous leukemia (AML). Serum IL-1ra, IL-1 beta, TNF alpha, GM-CSF, and SCF levels were measured in AML patients who received IL-4, IL-10, or amifosti ne. No significant changes in the serum levels of IL-1ra, IL-1 beta. TNF al pha, GM-CSF and SCF were found in AML patients who received amifostine. Bot h IL-4 and IL-10 were found to increase serum IL-1ra. This data is in accor d with the in vitro studies. However, IL-4 increased serum GM-CSF levels an d IL-10 increased serum IL-1 beta and TNF alpha levels. These in vivo effec ts of the two cytokines differ from their in vitro effects, Despite the sim ilar effects of IL-4 and IL-10 on cytokine production by AML cells in vitro . different effects were observed in AML patients in vivo. IL-4 increased s erum SCF levels, whereas IL-10 decreased serum SCF levels. IL-4 increased s erum GM-CSF levels, whereas IL-10 had no effect on them. Although IL-10 inc reased serum IL-1 beta and TNF alpha levels. IL-4 had no effect on them. Th ese findings indicate that the in vitro effects of IL-4 and IL-10 do not ne cessarily reflect their in vivo effects, and that the complex effects of th e two cytokines on serum cytokine levels make it difficult to predict their therapeutic potential.