Inhibition of neutrophil superoxide production by human plasma α1‐antitrypsin

[摘要]

We report here that human plasma α₁-antitrypsin (α₁-AT) inhibited human neutrophil O₂ ⁻ release elicited by a variety of stimulants. In comparison, the inhibitory capacities of two serine protease inhibitors, l-1-tosylamide 2-phenylethylchloromethyl ketone (TPCK) and soybean trypsin inhibitor (SBTI) and the human recombinant α₁-AT mutant, α₁-AT-Arg³⁵⁸ were in the order: α₁-AT - TPCK> α₁-AT-Arg³⁵⁸ > SBTI when cells were stimulated with concanavalin A plus cytochalasin E. These data suggest that, in human inflammatory fluks containing relatively high concentrations of α₁-AT (such as rheumatoid arthritis synovial fluids) (i) α₁-AT may down-regulate the inflammatory process by inhibiting the neurophil respiratory burst and (ii) serpin oxidation by neutrophil-released oxygen species is unlikely to occur.

[学科分类] 生物化学/生物物理

[关键词] α1-Antitrypsin;Serine protease inhibitor;Neutrophil respiratory burst;Superoxide anion radical;Inflammation;Human;α1-AT;α1-antitrypsin;TPCK;l-I-tosylamide 2-phenylethyl chloromethyl ketone;SBTI;soybean trypsin inhibitor;Con A;concanavalin A;Cyto E;cytochalasin E