Inactivation of recombinant human tumor necrosis factor-α by proteolytic enzymes released from stimulated human neutrophils

K. P.M. Van Kessel*, J. A.G. Van Strijp, J. Verhoef

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

67 Citations (Scopus)

Abstract

Activated human neutrophils (PMN) degrade rTNF-α resulting in a loss of cytotoxic activity against murine L-929 cells (L cells). This inactivation is mediated through proteases released from activated PMN. Exposure of TNF to H2O2, glucose oxidase, xanthine oxidase, or myeloper-oxidase-H2O2-halide did not affect TNF cytotoxicity for L cells. Exposure to trypsin, chymotrypsin, pronase E, or elastase, however, did diminish TNF bioactivity. FMLP-stimulated PMN in the presence, but not in the absence, of cytochalasin B reduced TNF activity, whereas PMA-stimulated PMN did not affect TNF. Stimulation of PMN with opsonized bacteria also induced TNF inactivation as well as the supernatant of FMLP-stimulated cells. Addition of protease inhibitors to the FMLP-stimulated cytochalasin B-treated PMN abrogated the inactivation of TNF cytotoxicity for L cells, whereas scavengers were not protective. In addition, PMN from a chronic granulomatous disease patient also decreased TNF bioactivity. Inactivation of TNF by activated PMN correlated with granule release and not with superoxide production. Exposure of TNF to proteases and FMLP-activated PMN also resulted in a loss of reactivity with anti-TNF antibodies, as measured by ELISA, and in the formation of an approximately 10-kDa split product from the 17-kDa rTNF molecule. Partial degradation of TNF by proteases released from activated PMN may result in a diminished TNF bioactivity and thereby contribute to the regulation of local inflammatory reactions.

Original languageEnglish
Pages (from-to)3862-3868
Number of pages7
JournalJournal of Immunology
Volume147
Issue number11
Publication statusPublished - 1 Jan 1991

Fingerprint

Dive into the research topics of 'Inactivation of recombinant human tumor necrosis factor-α by proteolytic enzymes released from stimulated human neutrophils'. Together they form a unique fingerprint.

Cite this