The past few years have seen significant growth in the number of known
chemokines. Along with expansion in this field has come an appreciati
on of a role for chemokines beyond the chemotaxis of leukocytes. In pa
rticular, it appears that these molecules may represent major products
of activated lymphocytes and that, in addition to chemotaxis, some of
them may also regulate the growth, activation, and differentiation of
lymphocytes.