The present invention relates to an isolated soluble CCR6 receptor polypeptide capable of binding to CCL18 and/or CCL20 and to a method for quantifying the concentration of a soluble CCR6 receptor polypeptide in a liquid sample from a subject. The present invention also relates to a method for detecting and/or prognosticating an interstitial lung disease or a cancer in a subject by determining the level of a soluble CCR6 receptor polypeptide in a sample from said subject and further provides a pharmaceutical composition comprising a compound capable of inhibiting the activity and/or the expression of CCL18 or CCL20 for the treatment of said diseases. The present invention further relates to an isolated polypeptide capable of binding to and inhibiting the activity of the chemokine receptor CCR6 and to a method for identifying further inhibitors of CCR6 receptor activity. The present invention also relates to a method for detecting an interstitial lung disease or a cancer in a subject by determining the level of CCR6 gene expression in a sample from said subject and further provides pharmaceutical compositions comprising inhibitors of CCR6 receptor activity and/or expression for the treatment of said diseases.
