Procoagulant synthesis by exudate and bone marrow-derived murine macrophages.

Abstract

Murine exudate macrophages elicited by different stimuli and bone marrow-derived macrophages were studied for their capacity to synthesize factor VII and tissue factor in a basal state and on stimulation with endotoxin (LPS). Cells elicited by different stimuli varied in their production of both factors. Thioglycollate-elicited cells generally made more, but not significantly more, tissue factor in response to endotoxin than cells elicited with periodate or streptococci. Cells elicited with proteose-peptone, fetal calf serum (FCS), or LPS produced less or very little tissue factor. Thioglycollate-elicited cells and cells elicited with streptococci or proteose-peptone consistently made more factor VII than cells elicited with periodate, FCS, and LPS. Bone marrow-derived macrophages were responsive to LPS by the production of tissue factor by the fifth day of culture, and this rose to a maximum by day 10. The maximal production of factor VII occurred on day 5 of culture and declined with longer cultivation. Factor VII production was not enhanced by LPS, and prolonged cultivation in the presence of LPS turned off the synthesis of both tissue factor and factor VII. We conclude that exudate cells are heterogeneous in the production of coagulant factors and that the production of these factors varies with the maturity of the cells. In addition, the production of the tissue factor and the factor VII were not necessarily expressed in a coordinate fashion.