Pentoxifylline enhancement of defective neutrophil function and host defense in neonatal mice.

Decreased neutrophil (PMN) chemotaxis is thought to contribute to the increased morbidity and mortality from infection in newborn infants. Pentoxifylline, a methylxanthine, has previously been shown to augment PMN chemotaxis in vitro. The authors therefore investigated the effects of pentoxifylline on 1) in vitro PMN chemotaxis, 2) in vivo leukocyte accumulation, and 3) protection against Staphylococcus aureus infection in newborn mice. Using a modified Boyden chamber system, they demonstrated that pentoxifylline significantly enhanced neonatal PMN chemotaxis in a dose-dependent manner. Additionally, pentoxifylline was found to increase PMN accumulation in vivo in a proteose peptone-induced peritonitis model. Finally, the survival rate in experimentally induced S aureus infection was 51% in neonatal mice given pentoxifylline, compared with 17% in a control (nonpentoxifylline) group (P less than 0.01). These data demonstrate pentoxifylline modulation of PMN migration and enhancement of host defense against bacterial infection.