Synthesis and anti-inflammatory activity of a chimeric recombinant superoxide dismutase: SOD2/3.
External surfaces of cells are normally protected by extracellular superoxide dismutase, SOD3, which binds to polyanions such as heparan sulfate. We constructed a fusion gene encoding a chimeric SOD consisting of the mature human mitochondrial SOD2 plus the COOH-terminal 26-amino acid heparin-binding "tail" from SOD3. This tail is responsible for the enzyme's affinity for endothelial surfaces. The fusion gene was expressed in Escherichia coli, and the fully active enzyme SOD2/3 was purified. Although native SOD2 has no affinity for heparin, SOD2/3 binds to a heparin-agarose column. In a rat model of acute lung injury induced by intratracheal instillation of IL-1, SOD2/3, SOD2, and denatured SOD2/3 showed 92%, 13.8%, and 0% reduction of lung leak, respectively. Only SOD2/3 prevented neutrophil accumulation. In the carrageenan-induced foot edema model in the rat, SOD2/3 reduced edema by 62% (P < 0.003) at a dose in which native SOD2 produced no significant effect. Thus SOD2/3 appears to have properties as a therapeutic anti-inflammatory agent that are greatly superior to other available forms of the enzyme.
Gao
Bifeng
B
Webb-Waring Institute, University of Colorado Health Sciences Center, Denver, Colorado 80262, USA.
Flores
Sonia C
SC
Leff
Jonathan A
JA
Bose
Swapan K
SK
McCord
Joe M
JM
D000818:Animals; D001483:Base Sequence; D002351:Carrageenan; D004195:Disease Models, Animal; D004487:Edema / Q000139:chemically induced / Q000188:drug therapy; D005121:Extremities; D015971:Gene Expression Regulation, Enzymologic; D006493:Heparin / Q000378:metabolism; D006801:Humans; D007375:Interleukin-1 / Q000494:pharmacology; D008297:Male; D008969:Molecular Sequence Data; D009504:Neutrophils / Q000276:immunology; D018384:Oxidative Stress / Q000276:immunology; D010957:Plasmids; D011014:Pneumonia / Q000188:drug therapy* / Q000276:immunology / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000276:immunology / Q000494:pharmacology*; D013482:Superoxide Dismutase / Q000235:genetics* / Q000276:immunology* / Q000494:pharmacology; D000099156:Superoxide Dismutase 2
D002351:Carrageenan; D006493:Heparin; D007375:Interleukin-1; D011993:Recombinant Fusion Proteins; D013482:Superoxide Dismutase; D000099156:Superoxide Dismutase 2; C441642:SOD3 protein, human; C499089:Sod3 protein, rat