The present invention relates to deletion and substitution mutant polypeptides of human chemokine -7 (Ck-7), as well as nucleic acid molecules encoding such polypeptides and processes for producing such polypeptides using recombinant techniques. In one aspect, the invention also relates to uses of the full-length and mature forms of Ck-7, as well as deletion and substitution mutants, in medical treatment regimens. In particular, the Ck-7 polypeptides described herein may be employed to treat a variety of conditions, including rheumatoid arthritis, inflammation, respiratory diseases, allergy, and IgE-mediated allergic reactions.