Inhibition of CD18-dependent adherence of polymorphonuclear leukocytes does not affect liver oxygen consumption in fecal peritonitis in pigs.

We tested the hypothesis that circulating polymorphonuclear leukocytes (PMNs), adhering to endothelium of the liver vascular bed are involved in the alterations of the liver oxygen delivery (DO2) and consumption (VO2) that is a result of fecal peritonitis in pigs. Twenty-two pigs were divided into three groups. Animals in group I (n = 7) served as controls. Fecal peritonitis was induced in groups II (n = 7) and III (n = 8). Animals in group III were pretreated with IB4, a monoclonal anti-CD18 antibody inhibiting adherence of PMNs to the endothelium. Peritonitis increased liver VO2 in groups II and III in spite of decreased liver DO2. In group I, circulating PMNs increased during the experimental period. Sepsis caused a decrease in the number of circulating PMNs in group II, an effect that was fully counteracted in group III, where the number of PMNs rose to control level. Myeloperoxidase activity and morphometric determination of PMN infiltration in liver biopsies virtually paralleled the circulating PMN count. Although fecal peritonitis is followed by a CD18-dependent leukopenia that can be counteracted by pretreatment with an anti-CD18 antibodies, this treatment does not affect the alteration in liver VO2 and DO2 observed.