[Procoagulatory activity of macrophages and monocytes of the guinea pig].

Guinea pig peritoneal macrophages and blood monocytes possess a membrane-bound tissue factor-like procoagulant activity. This activity can be induced to grow by mitogenic lectins and by lymphocyte products released specifically upon contact with immunizing antigens in vitro. The procoagulant activity can be easily measured by a plasma recalcification test. Guinea pig peritoneal cells and mononuclear blood cells from animals immunized with ovalbumin, bovine gamma-globulin or tetanus vaccine reacted to the corresponding antigen in a specific manner by expression of increased amounts of procoagulant activity (ovalbumin: + 16.9%; bovine gamma-globulin: + 26.8%, tetanus vaccine: + 23.5%). Supernatants from peritoneal cells were active in transferring the stimulus to neutral peritoneal cells which expressed thereafter higher amounts of procoagulant activity.