MONOCYTE PROCOAGULANT ACTIVITY - DEVELOPMENT OF A MICROTITRE PLATE CHROMOGENIC ASSAY

A monocyte procoagulant assay was developed based on the original meth od of Surprenant and Zuckerman, which quantitates a factor Xa-specific chromogenic substrate (at 405 nm) activated via the extrinsic coagula tion pathway. Normal tissue factor initiation of the pathway is replac ed by tissue factor generated from monocytes, stimulated by various ag ents including bacterial lipopolysaccharide, and antibody/antigen comp lexes. Hydrolysis of the chromogenic substrate is therefore directly p roportional to the degree of monocyte activation. Using a chromogenic substrate as an end-point the assay was performed in a standard microt itre plate.