Factor VII is a single chain glycoprotein zymogen that initiates the extrinsic coagulation pathway by forming a complex with exposed Tissue Factor and Ca2+. Factor VII in complex is rapidly cleaved to VIIa which activates Factor X and IX. Congenital Factor VII deficiency is rare and caused by heterogeneous decreased activity or antigen levels. Elevated Factor VII is associated with increased risk of coronary heart disease. The sensitive quantitative measurement of total human Factor VII antigen in plasma samples is easily performed with this 96 well strip format ELISA kit. Factor VII, VIIa, and VII in complex with Tissue Factor will be detected by the assay. The concentration of Factor VII in normal human plasma is 470 ng/ml. The assay measures total human Factor VII in the 0.2-100 ng/ml range. Samples giving human Factor VII levels above 100 ng/ml should be diluted in blocking buffer before use. A 1:20-1:100 dilution for plasma is suggested for best results. Human Factor VII will bind to the capture antibody coated on the microtiter plate. After appropriate washing steps, anti-human Factor VII primary antibody binds to the captured protein. Excess primary antibody is washed away and bound antibody is reacted with the secondary antibody. Following an additional washing step, TMB substrate is used for color development at 450nm. Color development is proportional to the concentration of Factor VII in the samples. A standard calibration curve is prepared using dilutions of purified Factor VII and is measured along with the test samples. All reagents and standards are provided in these ELISA kits.

The Human Factor VII standard provided in this kit is calibrated against the WHO International Standard for Human Plasma Factors II, VII, IX, X (NIBSC Code 09/172).