Portal de Periódicos da CAPES

Alpha 1-proteinase inhibitor is a neutrophil chemoattractant after proteolytic inactivation by macrophage elastase.

1988; Elsevier BV; Volume: 263; Issue: 9 Linguagem: Inglês

10.1016/s0021-9258(18)68951-3

1083-351X

Michael J. Banda, Audie Rice, Gail L. Griffin, Robert M. Senior,

Cell Adhesion Molecules Research

Mouse macrophage elastase, a metalloproteinase, catalytically inactivates human alpha 1-proteinase inhibitor (alpha 1-PI) by attacking a single peptide bond between Pro357 and Met358, resulting in Mr = 4,200 and 47,800 fragments. We show here that this proteolytically inactivated alpha 1-PI is a potent chemotactic factor for human neutrophils at a concentration of 1 nM. The chemotactic response is equivalent to that elicited by formyl-methionyl-leucyl-phenylalanine. Native alpha 1-PI does not stimulate chemotaxis. Purification of the two fragments of alpha 1-PI that result from proteolysis by macrophage elastase indicated that the Mr = 4,200 fragment is responsible for the chemotactic activity. However, the two proteolysis fragments do not dissociate from each other under physiologic conditions. Therefore, the ability of proteolytically inactivated alpha 1-PI to act as a mediator of inflammation is due to rearrangement of the alpha 1-PI molecule rather than to release of a cleavage fragment.