Receptors for maleylated proteins regulate secretion of neutral proteases by murine macrophages.

Abstract

Receptors for maleylated or acetylated proteins as well as for alpha-2-macroglobulin-protease complexes on macrophages serve as scavengers by mediating the uptake of macromolecules from the extracellular compartment. Described in this report is a novel function of these receptors on macrophages: regulation of neutral protease secretion. The binding of maleylated bovine serum albumin to macrophages triggered secretion of three neutral proteases: neutral caseinases, plasminogen activator, and cytolytic proteinase. Release of acid phosphatase, however, was not induced. An important biological consequence of protease secretion by macrophages, tumor-cytolysis, was also triggered by engagement of the receptor for maleylated bovine serum albumin. By contrast, the binding of alpha-2-macroglobulin-protease complexes to the macrophages suppressed secretion of all three proteases. Thus two receptors heretofore believed to serve principally as scavengers also regulate secretory functions of macrophages.

• Authors: W J Johnson, S V Pizzo, M J Imber, D O Adams
• Journal: Science (New York, N.Y.) (Science) Vol. 218 Issue 4572 Pg. 574-6 (Nov 05 1982) ISSN: 0036-8075 [Print] United States
• PMID: 6289443 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Glycoproteins
• Receptors, Cell Surface
• Peptide Hydrolases
• Plasminogen Activators
• Metalloendopeptidases
• caseinase

Topics

• Animals
• Cells, Cultured
• Glycoproteins (metabolism)
• Macrophages (enzymology)
• Metalloendopeptidases
• Mice
• Peptide Hydrolases (metabolism)
• Plasminogen Activators (metabolism)
• Receptors, Cell Surface (physiology)