A monoclonal antibody against migration inhibitory factor (MIF) obtained by immunization with MIF from the human lymphoblast cell line Mo.

A monoclonal antibody-secreting hybrid cell line, E7, was constructed from myeloma cells and spleen cells from BALB/c mice immunized with partially purified human MIF from culture fluid of the human T-lymphoblast cell line Mo. The hybrid cell line E7 was selected by screening hybridoma cultures for their capacity to adsorb added MIF activity when assayed together with rabbit anti-mouse IgG-coupled to protein A-Sepharose. The monoclonal antibody produced by the cloned hybridoma E7 also directly neutralized MIF activity from Mo cells and two species of MIF from the culture fluid of human peripheral blood lymphocytes, but did not neutralize IFN-gamma from Mo cells and from human peripheral blood lymphocytes. This antibody reacted also with a component in phytohemagglutinin preparations with an apparent molecular weight of 60,000; however, it did not react with the active tetramer of phytohemagglutinin.