MOUSE MACROPHAGE-DERIVED MONOCYTE CHEMOTACTIC PROTEIN-3 - CDNA CLONING AND IDENTIFICATION AS MARC FIC/

When the mouse macrophage cell line WEHI-3 is triggered with LPS it pr oduces proteases and secondary cytokines including interleukin-6 and c hemokines. In an attempt to isolate the mouse homologue of the human m onocyte chemotactic (MCP-3), a cDNA library from LPS-stimulated WEHI-3 cells was screened with the full-size human MCP-S cDNA. The longest c DNA out of several positive clones was sequenced and encoded a protein of 97 residues. Except for a third codon letter mismatch it was ident ical to the mouse MARC cDNA and encoded the MARC protein. The murine F ic cDNA, which encodes a Marc-mutant protein with an arginine substiti on for alanine, was not identified in the other sequenced homologous i solates. Similar to the human system, in which MCP-3 is most related t o MCP-1, MURINE MCP-3 was found to be more homologous to mouse MCP-1/J E than to other murine C-C chemokines. We therefore postulate that MAR C/FIC is the mouse MCP-3. (C) 1994 Academic Press, Inc.