DEVELOPMENT OF A SANDWICH ELISA FOR OVINE GRANULOCYTE-MACROPHAGE COLONY-STIMULATING FACTOR

Recombinant ovine granulocyte/macrophage colony-stimulating factor (rO v GM-CSF) has been expressed in Chinese hamster ovary cells. A stable, cloned line of these cells has been established which secretes high l evels (40 mu g ml(-1)) of rOv GM-CSF. Three murine monoclonal antibodi es (mAbs) were produced which reacted with rOv GM-CSF on Western blots . These mAbs also neutralised the activity of both recombinant and nat ive Ov GM-CSF in a bone marrow haemopoietic progenitor cell assay. Two of the mAbs, which recognise mutually exclusive epitopes, were select ed for the development of a sandwich enzyme-linked immunosorbent assay (ELISA) to measure GM-CSF in biological samples of ovine origin.