CCR3 and neoplasm: To investigate the functional role of eosinophils in mediating tumor regression, we intraperitoneally injected an isotype control or anti-mouse CD193 (CCR3) antibody (clone# 6S2-19-4) 13 or anti-mouse CD170 (Siglec-F) antibody (clone #238047) 14 to deplete eosinophils in vivo.