A peptide which is a human homologue of guinea pig eotaxin or a novel chemokine, in particular, a human CC chemokine having an activity on human eosinocytes; the structural gene of the peptide; an expression vector having the gene; a transformant having the expression vector introduced thereinto; a process for producing the peptide by using the transformant; a monoclonal antibody against the peptide; a method for assaying the peptide by using the monoclonal antibody; and a method for screening an agonist or antagonist of the peptide.
