Effect of pentoxifylline on polarization and migration of human leukocytes

Leukocyte polarization has a key role in the induction and effector phases of immune response. We assessed the effect of pentoxifylline (PTX) on the polarization and migration of human lymphocytes and neutrophils. A dose-dependent, inhibitory effect on the polarization of lymphoid cells induced by chemokines or IL-15 was found. In addition, PTX interfered with the chemotaxis of peripheral blood T cells and T lymphoblasts. A similar effect was observed on the transendothelial migration of these cells. In addition, the polarization of neutrophils, its adherence to endothelium, and their transendothelial migration, induced by different stimuli, were inhibited by PTX. By contrast, this drug had only a mild effect on endothelial cells and a partial inhibition on the induction of ICAM-1 expression by TNF-alpha. The inhibitory effect of PTX on leukocyte polarization and extravasation may contribute significantly to the anti-inflammatory and immunoregulatory activity of this drug.