Expression of lymphotoxins and their receptor-Fc fusion proteins by baculovirus.

The tumor necrosis factor (TNF) cytokine and receptor superfamily plays critical roles in immune physiology. Several members of this family, such as the lymphotoxins (LT alpha and LT beta), Fas ligand, and TNF, induce cell death in some normal and transformed cells, but also induce cell growth and differentiation. The receptors for these ligands, when expressed as fusion proteins with the Fc region of IgG, function as potent antagonists of biological activity. The receptor-Fc fusion protein is a highly versatile reagent that can be utilized in virtually all the formats designed for antibodies. In this chapter we describe the expression, purification, and assays for lymphotoxins and their receptors, using a recombinant baculovirus system.