Conjugates containing as a ligand chemokine receptor targeting agents,
such as chemokines, and a targeted agent, such as a toxin are provided.
These conjugates are used to treat inflammatory responses associated with
activation, proliferation and migration of immune effector cells,
including leukocyte cell types, neutrophils, macrophages, and
eosinophils. The conjugates provided herein are used to lessen or inhibit
these processes to prevent or at least lessen the resulting secondary
effects. In particular, the conjugates can be used to target toxins to
receptors on secondary tissue damage-promoting cells. The ligand moiety
can be selected to deliver the cell toxin to such secondary tissue
damage-promoting cells as mononuclear phagocytes, leukocytes, natural
killer cells, dendritic cells, and T and B lymphocytes, thereby
suppressing the proliferation, migration, or physiological activity of
such cells. Among preferred conjugates are fusion proteins having a
chemokine, or a biologically active fragment thereof, as the ligand
moiety linked to a cell toxin via a peptide linker of from 2 to about 60
amino acid residues.