INTRODUCTION

Filgrastim (Granulocyte colony-stimulating factor (G-CSF or GSCF)), also known as colony-stimulating factor 3 (CSF 3), is a glycoprotein that stimulates the bone marrow to produce granulocytes and stem cells and release them into the bloodstream. The pharmaceutical analogs of naturally occurring G-CSF are called filgrastim and lenograstim. Filgrastim is used to treat neutropenia,[9] stimulating the bone marrow to increase production of neutrophils. Causes of neutropenia include chemotherapy and bone marrow transplantation.

PRINCIPLE OF THE ASSAY

This assay employs the indirect sandwich enzyme immunoassay technique. Anti-GCSF is coated onto a 96 well microplate. Calibrator and test samples prepared by dilution into assay buffer and are pipetted into the appropriate wells. GCSF present in biological matrices is bound by the immobilized anti- GCSF antibody. After washing away any unbound substances, tagged anti-GCSF secondary antibody is added to the wells. After washing, diluted detection reagent is added to the wells. The plate is washed to remove any unbound antibody-enzyme reagent and a substrate solution is added to the wells for color development. The color development is proportional to the amount of GH present in test samples. The color development is stopped and the intensity of the color is measured.