TY - JOUR
T1 - Novel anti-factor D monoclonal antibody inhibits complement and leukocyte activation in a baboon model of cardiopulmonary bypass
AU - Ündar, Akif
AU - Eichstaedt, Harald C.
AU - Clubb, Fred J.
AU - Fung, Michael
AU - Lu, Meisheng
AU - Bigley, Joyce E.
AU - Vaughn, William K.
AU - Fraser, Charles D.
N1 - Funding Information:
This study was supported by grants from the National Institutes of Health, National Heart, Lung, and Blood Institute (Grant # HL65061), Bethesda, Maryland, and from Tanox, Inc., Houston, Texas. The authors thank Blake A. Deady and Aimee Porter for their excellent technical assistance and Virginia Fairchild for editorial assistance. Special thanks go to Professor Tom Eirik Mollnes, of the Department of Immunology and Transfusion Medicine of the University of Tromsø in Norway, for providing us reagents for sC5b-9 ELISA.
PY - 2002
Y1 - 2002
N2 - Background. Adverse outcomes after cardiopulmonary bypass (CPB) are often related to systemic inflammation triggered by complement and leukocyte activation. To determine how inhibition of the alternative complement pathway affects systemic inflammation and tissue injury, we studied a novel monoclonal antibody (Mab), anti-human factor D murine Mab 166-32, in baboons. Methods. Fourteen baboons (mean weight, 15 kg) underwent hypothermic CPB. The treatment group (n = 7) received a single injection of anti-factor D Mab 166-32 (5 mg/kg), and the control group (n = 7) was given saline solution. After initiation of CPB, all animals were subjected to 20 minutes of core cooling (rectal temperature, 27°C), followed by 60 minutes of aortic cross-clamping, 25 minutes of rewarming, and 30 minutes of normothermic CPB. Blood samples were collected before CPB, during CPB, and 1, 2, 3, 6, and 18 hours after CPB. To measure neutrophil and monocyte activation, we performed flow cytometry for CD11b expression, ELISA for complement activation (Bb, C3a, C4d, and sC5b-9) and interleukin-6 (IL-6) production, and tissue injury studies for creatine kinase MB isoenzymes (CK-MB), creatine kinase (CK), and lactic dehydrogenase (LDH) levels. Results. Anti-factor D Mab almost completely inhibited plasma Bb, C3a, and sC5b-9 production during CPB (P < .001). CD11b expression on neutrophils (129 ± 5% vs. 210 ± 42%; P = .0006) and on monocytes (139 ± 14% vs. 245 ± 43%; P = .0002) was also lower in the treatment group during CPB. The treated animals had a significantly smaller increase in plasma IL-6 concentrations than did the control animals (71 ± 27 pg/mL vs. 104 ± 54 pg/mL; P = .0002). CK-MB levels were also lower in the treatment group 6 hours after the end of CPB (204 ± 30 vs. 335 ± 59 IU/L; P = .003) and 18 hours after the end of CPB (P < .05). Creatine kinase levels (6 and 18 hours after the end of CPB) and LDH levels (3 and 6 hours after the end of CPB) showed patterns similar to those of CK-MB (P < .05). Conclusions. The alternative complement pathway plays a major role in systemic inflammation during CPB. Inhibition of complement activation via the alternative pathway by anti-factor D Mab 166-32 significantly reduces leukocyte activation and tissue injury in our baboon model.
AB - Background. Adverse outcomes after cardiopulmonary bypass (CPB) are often related to systemic inflammation triggered by complement and leukocyte activation. To determine how inhibition of the alternative complement pathway affects systemic inflammation and tissue injury, we studied a novel monoclonal antibody (Mab), anti-human factor D murine Mab 166-32, in baboons. Methods. Fourteen baboons (mean weight, 15 kg) underwent hypothermic CPB. The treatment group (n = 7) received a single injection of anti-factor D Mab 166-32 (5 mg/kg), and the control group (n = 7) was given saline solution. After initiation of CPB, all animals were subjected to 20 minutes of core cooling (rectal temperature, 27°C), followed by 60 minutes of aortic cross-clamping, 25 minutes of rewarming, and 30 minutes of normothermic CPB. Blood samples were collected before CPB, during CPB, and 1, 2, 3, 6, and 18 hours after CPB. To measure neutrophil and monocyte activation, we performed flow cytometry for CD11b expression, ELISA for complement activation (Bb, C3a, C4d, and sC5b-9) and interleukin-6 (IL-6) production, and tissue injury studies for creatine kinase MB isoenzymes (CK-MB), creatine kinase (CK), and lactic dehydrogenase (LDH) levels. Results. Anti-factor D Mab almost completely inhibited plasma Bb, C3a, and sC5b-9 production during CPB (P < .001). CD11b expression on neutrophils (129 ± 5% vs. 210 ± 42%; P = .0006) and on monocytes (139 ± 14% vs. 245 ± 43%; P = .0002) was also lower in the treatment group during CPB. The treated animals had a significantly smaller increase in plasma IL-6 concentrations than did the control animals (71 ± 27 pg/mL vs. 104 ± 54 pg/mL; P = .0002). CK-MB levels were also lower in the treatment group 6 hours after the end of CPB (204 ± 30 vs. 335 ± 59 IU/L; P = .003) and 18 hours after the end of CPB (P < .05). Creatine kinase levels (6 and 18 hours after the end of CPB) and LDH levels (3 and 6 hours after the end of CPB) showed patterns similar to those of CK-MB (P < .05). Conclusions. The alternative complement pathway plays a major role in systemic inflammation during CPB. Inhibition of complement activation via the alternative pathway by anti-factor D Mab 166-32 significantly reduces leukocyte activation and tissue injury in our baboon model.
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U2 - 10.1016/S0003-4975(02)03656-1
DO - 10.1016/S0003-4975(02)03656-1
M3 - Article
C2 - 12173813
AN - SCOPUS:0036322732
SN - 0003-4975
VL - 74
SP - 355
EP - 362
JO - Annals of Thoracic Surgery
JF - Annals of Thoracic Surgery
IS - 2
ER -