Monoclonal Antibody That Alters Leukocyte Function

Pentobarbital anesthetized dogs were subjected to 90 minutes of left circumflex coronary artery (LCCA) occlusion followed by 72 hours of reperfusion. Control or anti-Mol (904) F(ab')2 fragments of monoclonal antibodies were administered intravenously at a dose of 1 mg/kg beginning 45 minutes after occlusion and at a dose of 0.5 mg/kg at 12, 24, 36, and 48 hours after reperfusion. Myocardial infarct size expressed as a percentage of the area at risk (IN/AR) measured postmortem after 72 hours of reperfusion was significantly reduced by 904 F(ab')2 (21.6±2.8%, n=8) compared with control F(abl2 (37.4±5.8%, n=8; p<0.025). There were no significant differences between groups in heart rate, mean arterial blood pressure, rate-